,á^*.:

MODERNIZING

\'0

aft"'"'
Improved cotton ginning practices and better ginning establishments preserve the

inherent qualities o( the cotton fiber, aid in keeping planting seed pure, and tend to

increase profit. Most ginners would modernize their establishments in whole or in

part if they were assured that they were taking the right steps and that they were following the recommendations of State and Federal agencies working toward these

improvements.

In the case of existing cotton ginning establishments it is frequently a question

whether to remodel or to rebuild completely. This question can best be answered by

asking other questions.

Is the present equipment still serviceable and in good condition? If so, is it

adequate for the present requirements of conditioning, cleaning, and extracting both

hand-picked and machine-harvested cottons?

Will the cost of modernization of either equipment or buildings be less by remodeling than by entire replacement? Which will attain the main objectives with

regard to both public and private interest?

Is the present or proposed establishment economical in operating the equipment

for cotton handling, ginning, and disposal of products?

Does the present or proposed establishment comply with latest safety practices and

public codes on dust and smoke elimination, on insect quarantine requirements, fire

insurance underwriters' limitations, and on preservation of purity of planting seed?

This Handbook is intended to help ginners ond cotton producers to answer these

questions and to plan according to the needs of their own individual circumstances and

those of their communities.

CONTENTS

Page

Evaluation of Existing Gin* 1

Elements oí Modem Gins 1

Arrangement of Buildings and Grounds S

Building Construction for Gins 8

Cotton Docks and Bale Storage 5

Seed-Cotton Bulk-Flow Control 5

Conditioners 5

Cleaners and Extractors 5

Feeders and Gin Stands 11

Lint Cleaners 12

Handling Seed and Trash 13

Air Piping and Fans 15

Piping for Seed Cotton 15

General Rules for Piping 17

Fans 18

Air-Blast Systems and Gages SO

Pase

Gin-Machinery Auxiliaries S3

Power Unih 23

Power Transmission S4

Separators and Distributors ¡4

Lint Flues and Condensers iS

Presses, Trampers, and Pumps i^

Scales for Trucks, Bales, and Seed St

Moisture Restoration and Treatments ¡^

Examples of Modernization '^

Maintenance of Gins ^

Lubrication '°

Repairing '•

Fire and Safety Precautions ^'

Appearance of Ginning Establishments ^'

Appendix "

Washington, D. C. tnu«d August 1956
MODERNIZING

COTTON GINS

By Agricultural Engineering Research Branch, Agricultural Research Service

EVALUATION OF EXISTING GINS

Considei-ation should be given to the location of

the gin, because conditions have so changi'd since

1940 that some gins are now in unsatisfactory

locations. Accessibility to roads and transportation facilities and the proximity to competitors

may have changed so much since the original

establishment of the ginning plant as to affect

materially the present value of the plant.

A simple sketch of the property showing the

relative positions of the several buildings and

accompanied by marginal notes describing the

territory served, the average number of bales of

cotton ginned over a representative period, the

increase or decrease in cotton acreage in the

community, and other influencing factors will be

of assistance in making a complete evaluation.

The inspection of the buildings on the property

should be made only by a person experienced in

building. Definite information should be obtained

regarding the condition of each building, the

feasibility of remodeling, and the adecjuacy of the

plant for use imder present coiiditions. From this

information a builder can readily provide estimates

covering the cost of additions, alterations, and

repairs. If a new all-steel, 24-foot plate-height

ginning building of ample width is to replace a

wooden building, a preliminary estimate of $6.25

per square foot of floor area may be used. This

estimate is based on 1954-55 materials and labor

costs.

Cost of equipment and machinery may be most

satisfactorily obtained directly from tlie manufacturers, because they can advise regarrling items

entering into the purchase, shipment, labor, and

erection.

' Many of the improvements in ginning equipment

reported in tliis Handbook were developed by staff members of the Cotton Ginning Research Laboratories, which

are located at Stoneville, Miss.; Mesilla Park, N. Mex.;

and Clerason, S. C. This Handbook is a revision of and

supersedes Farmers' Bulletin 1802. "Modernizing Cotton

Gins," by C. A. Bennett, T. L. Baggette, and F. L. Gordes.

381692°—56 1

ELEMENTS OF MODERN GINS

A modern cotton gin plant is fire resistant,

conveniently arranged inside and outside, and

properly liglited and ventilated, either artificially

or naturally. It has cleaning or extracting equipment suited to the production and harvesting

practices of the community, and the gin stands

are equipped with lint cleaners for further cleaning of the cotton. Provision is made for artificially drying green, damp, or wet cotton. The saw

shafts of the gin stancls are prefei-ably dh'ectl_v

connected for driving, and there is a minimum of

shafting and belting. Bearings are of the antifriction type rather than of the babbitted design.

Cotton piping and fans are of a size that contributes to economy in power consumption, and the

rate of feeding the seed cotton to the ginning

sj'stem is automaticalljr controlled with selective

regulation devices, for bulk suction as well as

individual gin stands.

Seed is handled from the gin stands by pureseed, self-cleaning belts and pneumatic systems.

The belts may discharge to mechanical lifts or

through sealed dropper wheels into small-pipe

seed-blow lines, which in turn deliver the seed to

scales or bins.-

Power-transmitting equipment for auxiliaries

now consists of high-speed countershafts; antifriction bearings; high-speed silent V-belts, chains,

and roller chains; and gear reducers. These

devices liave generally replaced the old-stjde line

shafts with babbitted bearings, flat-belt or rope

drives, gears, and countershafts. Seed scales are

becoming standard equipment for accurately

weighing seed purchased from the farmer. A

modern gin also has a convenient weatherproof

elevated hopper to hold the seed temporarily

until it is delivered to trucks.

Means for disposing of foreign matter from the

2 BENNETT, C. A., and FRANKS, G. N. COTTONSEED

HANDLING WITH SMALL AIR PIPES. U. S. Dept. AgT.

Cir. 768, 8 pp., illus. 10-18.

1
AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

plant are desirable. Several forms are described

in the section, Handling Seed and Trash, pa^^e 13.

Modern gins in certain regions also liave adequate facilities for storage of bales where they will

be protected a,gaiust weather and fire. Sl'ielter

sheds protect incoming loads of cotton against

rain. Seed-cotton storage houses or special large

trailers are used in some areas to provide for iiolding

seed cotton in storage for transferring it from

storage to the gin.

Arrangement of Buildings and Grounds

Among the factors to consider in deciding on the

best arrangement of the ginning buildings are the

shape and size of the lot, the location of entrances

and exits with respect to the public highways, the

position of railroad tracks, and the metliod of

handling wagon and truck traffic thi-ough the

entrances and exits of the lot.

ligure 1 shows tlu'ce good lot layouts for the

arrangement of buildings. The shape and size

of the lot and the location of the gin with reference

to roads and railroads may prevent the adoption

of ideal arrangements, so no hard and fast rule

can be laid down.

No shelter sheds or other accessories have been

indicated in the suggested layouts, because the

number and location of such accessories are

largely dependent on local conditions and practices. Gins in dift'ercnt regions handle cotton in

dift'erent ways. Weighing procedures are not at

all standardized, except that, in general, the

truck scale is either in front of the office or beneath

the suction pipe of the gin.

allBuilding Construction for Gins

If gin buildings are not of masonry or

metal construction, they should be of heavy,

mill-type timber coated with fire-resistant materials.

Good illumination and ample headroom are necessary. Figure 2 shows gin buildings with desirable

dimensions. Single-battery buildings should be

30 or more feet in width, with added side extensions for special machinery at ground level;

double-l)attery outfits require widths of 48 feet or

more, and buildings should have at least 24 feet

between the floor and roof plate. The length of

the building should be proportionate to the number

of gin stands and the space required for other

machinery and service activities. Straight-line

roofs are desirable, but offsets are frequently

employed in l^-story gins to obtain ample headroom over the press platform.

In new all-steel buildmgs, full-length overhung

truck sheds and runways for approach and unloading are favored because there are no posts

to be damaged by careless driving or accident.

This necessitates strengthening certain parts of

the building for ample support. Such construction is particularly desirable on city lots and other

restricted spaces.

The roofs of modern gin buildings may be flat,

pitched, or curved, but, above all, they should be

fireproof and readily accessible for cleaning and

repair. Many tj^pcs of trusses are in use, the

best forms being of structural steel or heavy

timber framed so that block-and-tackle loads

may be supported from the lower chords. By

selecting the roof trusses with this in mind, the

Wagon

seed bin. /

Bale platform

SEED

HOUSE COTTON GIN

Overhead' w, ^

conveyor ^^2°" /.

runway^

Overhead ^

ScaieSi suction pipe

COTTON HOUSE

OFFICE

A

Unloading shed

I I111 nil II11II11II !

R.R. SEED

HOUSE

5i

V I L J Wagon seed bin

Overhead conveyor

COTTON GIN

B

'Wagon

__; runway

Overhead suction pipe

Scalesii

OFFICE

ID

(^^ Unl oading shed

COTTON HOUSE

Engine room.

Wagon I—*l Pa'e

ru_nw_ay_JL_|_^°:%

COTTON GIN

AND OFFICE

^Scales

Wagon seed bin [ ]

"«^ Overhead

suction pipe ^

and conveyor Œ

.-j

SEED

HOUSE

COTTON Unloading shed

HOUSE

c

FIGURE 1.—Lot layouts for cotton-gin buildings: .4. l^lan with operations controlled from a special office on the grounds;

B, plan in which the office may be either separate or within the ginning buildings; and C, plan offering efficient supervision of operations.
MODERNIZING COTTON GINS

installation, removal, and rcaiTangcment of ginning machinery are made safer and simpler.

If a gin bnilding has more than one story or

platform in connection with a ground-level lioor,

inclines or ramps are ):)etter than steps for moving

bales and heavy machinery.

Buildings should be made ratproof wherever

possible. Concrete floors, parapets, and guards

make this a relatively simple nuitter in moik'ni

construction, if properly designed and reinforced.

Single-story gin buildings with concrete floors

have been gaining in favor because they are

durable and permit more rigid installation of

equipment. For such buildings, the bale presses

may be either of the type for up-packing from a

pit, or the single-story down-paclving type. If a

submerged lint flue is to be used with the machinery, its trench may drain to the press pit where

a small automatic-float pump maintains diyness

in both trench and pit.

Some form of crane, incline, or lift may be

needed to raise the leales from the ground level

to a platform or truck bed, unless the floor level

is unusually high or the ))ale scale is on a trolley

hoist that permits loading after weighing.

In some cases a l)|i-story gin building is pi'cferred to a single-story building. In it machinery

nmy be kept on the ground level and yet permit

the use of a 2-story press in conjunction with an

elevated platform of stfuctural steel or reinforced

concrete having a lialf cellar beneath, with full

headroom for pump, workbench, storage spaces,

and miscellaneous machinery.

Few 2-story gin buildings are now being built.

Tliese buildings are usually framed with wood

and sheathed with galvanized iron. The principal

advantages of a 2-story gin building are that the

ground floor may be used for seed sacking directly

beneath the gin stands and that the main line

shaft may be placed on concrete pedestals so that

FiGUEE 2.—Dimensions of modern gin buildings: A, One-story &n: B, i}o-story gm.
AGR. HANDBOOK 99, U. S. OKPT. OF AGRICULTURE

-^i^

J3

Wagon

runway

Unloading fan

i I oft

D — 12-

D G

I II ■■' ^ II

Floor

ELEVATION

Under floor piping

to gin out bins x^

Overhead piping

to fill bins,

FLOOR PLAN

FiüLRE 3.—Priiicii)al diineiisioiis of typical houses for the slorani' of scrd cotton: -1. Octagonal storage house; B, rectaiigular storage house. Some of these houses are now built with 24-foot plate height.

belt drives may be carried upward through the

ginning floor withotit occupying too much space

or being hazardous to woii^ers. However, ginning

machinery usually operates with less vibration

in a 1- or l)-2-story building where it can be solidly

mounted.

Gin buildings are seldom constructed to contain

the seed cotton and seed storage. From the

viewpoint of fire under\\TÍters, there are good

reasons for the gin building to be separated from

other buildings on the premises. Vov many

States—since 1954 instrtictions were pronnilgaled

by underwi-iters—minimum distances of 40 feet

between buUdings, 40 feet from buildings to

overnight bale storage, and 100 feet to incinerators

arc required by instirance authorities if lowest

rates are to be obtained. For open cottonstorage yards, the 1954 i-ulcs are that no gin

building may be closer than 200 feet and no

incinerator closer than 500 feet.

Figm-e 3 gives diagrams and dimensions for

seed-cotton storage houses that are used tlu-oughout the Cotton Belt. The bin dimensions frequently vary from those shown. The octagonal

cotton house is compact and may be filled either

by the suction-dropper or rembcrt-type cotton

fan. In a few instances the suction fan is within

the gin building proper, and the pipe to the cotton

house is used to fill the cotton house, to cool and

dry stored seed cotton when damp, and to transfer

seed cotton to the gin stands when the house is

being emptied. Rectangular cotton houses are

preferred in some sections; and both belt and

pneunuitic systems are used for fihing the bins.

These hotises are usually single-stor}', framed

with wood, and sheathed ^\-ith galvanized iron.

The floors are preferably of wood because concrete

floors often collect moisture, which is detrimental

to the cotton.

Modern gins, however, are now making significant savings in labor and building costs by resorting for temporary storage to demountable

trailers with screen sides. These trailers serve

22

k

J'

4_ y-Doors-^

\ j

•-J hIx xlO

N /K }^Ij

B

FKURE 4.—Principal dimensions of typical houses for

the storage of cottonseed: A, Truck-bed height seedstorage house; B, elevated seed-storage house with driveway underneath.
MODERNIZING COTTON GINS

dual pui'poses of hauling seed cotton from the

fields and providing storage at the gin yard until

they are unloaded at the gin suction telescope.

Tarpaulins or open shelter sheds afford protection

against inclement weather between time of

harvesting and ginning of these trailer loads.

Aii'-cooling systems are applicable.

Storage houses for cottonseed may be of the

types shown in figure 4.

Cotton Docks and Bale Storage

The form and extent of cotton docks in a large

measure depend on the building and grounds. It

is customary to have a sheltered dock at the end

of the gin house with bale runway and bale platforms, either unsheltered or sheltered, as shown

in figure 5, A and C. The elevated skeleton platform (fig. 5, B) is a unique means of handling

cotton bales where shelter is not provided. The

bale house shown in part D affords complete

protection in rainy weather.

Fire hazards to buildings and bales warrant

fireproof construction and the adoption of firepreventing measures. It is good practice to have

bale-storage facilities 200 feet or more from the

gin house to prevent spreading of fire from bales

to the gin proper.

Seed-Cotton Bulk-Flow Control

An outstanding recent development enables all

ginning systems to do theh best work by providing

controlled flow rates of bulk raw seed cotton from

trucks or bins at the gin suction pipe. Several

types of this control mechanism are on the market.

The United States Department of Agriculture

design of this apparatus is illustrated in figure 6,

A, as an optional miprovement to preliminary

drying and cleaning at cotton gins. A more

detailed sketch will be found in figure 37 in the

Appendix.

Conditioners

In most sections of the Cotton Belt modernization of the ginning outfit calls for the installation

of conditioning or drying apparatus. Seed cotton that is too high in moisture content will not

clean or gin properly. The production of smoothly ginned, high-qualitj^ samples requires precise

control of air temperatures and volumes as well

as time of exposure, together with selective automatic feed control of seed-cotton flow through

the system.

Many types of conditioners employing the

drjdng process developed by the Department

Cotton Ginning Laboratories are now on the market. (This process is covered bv public patents

Nos. 1,707,929, 1,871,773, and 2,078,309, which

are dedicated to the free use of the people.)

Driers may be located either on the ground

level or over the distributor or overhead cleaner.

Two methods of tower-drior installation are

shown m figure 6, which also depicts the bulk-flow

control.

Among the other forms of driei-s on the market

usnig the hot-air drying process are the big-reel

driei', the multiple-trough drier, the unit extractorfeeder drier, and tlieoverhead cleaner-drier. These

driers are shown in figure 7.

Anothei- drying system not shown utilizes a

reml)ert-type fan with a "split suction," drawing

hot air from a heater and the cotton from the

trucks, after which the fan discharges to the

tower. A fan having a capacity of 5,40f) or more

cubic feet of air per minu te is necessary for such dualpurpose systems. Installations of' this type are

especially applicable to small gins having small

vohmies and limited power.

The sources of heat for driers may be direct

or indirect furnaces using natural gas, butane, or

fuel oil; boilers; or arrangements for utilizing

waste heat from a diesel- or gas-engine exliaust

and radiator. It is generally desirable to install

the form of drier that will not interfere with the

ginning service and will require a minimum of

additional power. Either installation shown in

figure 6 permits the vertical diier to be used veiy

effectively with or without heat. Some of the

other forms of driers shown in figure 2 are, by

various methods of installation, able to achieve

the same effect.

For compactness and greater flexibihty in installing and operating, the tower driers have

floor spacings that range from 8 to 12 inches.

Connections between the first drier discharge

and the delivery to gimnng units frequentlj^

include a boll and rock trap developed at one of

the Cotton Ginning Research Laboratories (fig. 8).

The trap may include a permanent magnet for

tramp iron. Four tentative positions_ of strip

magnets have been approved by an interstate

engineers-underwriters committee; namely, positions 1 and 2 in tower driers or discharge transition as shown in figure 8; position 3, in discharge

connection from airline cleaner; and position 4,

in discharge piping from big-reel and conveyor

driers.

From the viewpoint of cotton mill experiences,

a minimum fiber moisture content of 5 percent is

desirable during the ginning treatments (table 1).

Cleaners and Extractors

Several factors determine the extent to wliich

cleaners and extractors should be employed in

cotton ginning establishments. These include

the methods of harvesting used in the locality

of the gin, the kinds of cotton, and regional

weather conditions as they affect fiber moisture

and leaf. .

Cleaners may be oljtained in a variety ot lorms,

such as the axial-flow, cross-drum, or serpentine
6 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

FIGURE 5.—Cotton-gin bale storage: A, Unsheltered storage on ground level;

B, unsheltered, elevated; C, sheltered, open sides; D, sheltered, enclosed.
Separahor

Heaher—) Vacuum wheel

MODERNIZING COTTON GINS

from f-ruck

V~or bin Separa|-or

Hoh air

Feed (^

'conhro'

Cleane

Dislribul-or

FIGURE 6.—Schematic diagrams of tower or vertical drier installations: A, Draw-through or suction tvpe, which may

have a full-length or stub tower; B, blow-through type with stub tower. The towers may be connected to the cleaners

by piping instead of directly, as shown in B.

Col-hon inleh VenP shack Separahor

^"I"'i=r Revolving screen | Seed cohhon / ho fan

l^^j^^j^ and ribbon conveyor-^ * ^ from hruck

rjghi and left hand

drying hroughs;>

oh air

Trashi^auger ^ Hoh air Ouhleh

r

OuMeh—-i

from truck

Dishribuhor

N

Hoh air

Feeders

1=1^^ Gin shands .3i

ho

Dishribuhor

A KSuchion Pan

FiGüEE 7—Various forms of commercial driers: .1, Big-reel drier; B, multiple-trough drier; C, unit extractor-feeder

drier; and D, overhead cleaner-drier.
8 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

Incomini seed cotton ' -^

Either of the positions

MB or MO is suitable

location of single long

strip magnet.

Hot airx

FIGURE 8.—Schematic diagram, showing location of boll

and rock trap with suitable location of single long-strip

permanent magnet for tramp iron.

types.^ CyliiitU'rs for cross-drum types of cleaners may be cc|uippecl with spikes, spider arms, or

paddles. In general, airline cleaners permit only

a horizontal flow of the seed cotton from inlet

to the outlet of tlie machine. Gravity-type

cleaners permit a vertical flow of the cotton.

Inclined gravity cleaners are common where there

is little headroom. Modern forms of inclined

gravity-type cleaner-separator installations are

shown in figure 9. The separator is mounted

at the lower end of the cleaner (fig. 9, A) in gins

where headroom is limited. Frequently the

separator is placed at the upper end with a bypass

so that the cotton may be discharged either to the

cleaner or directly into the distributor (fig. 9, B.)

Gravity-type cleaners, when fitted with vacuumwheel discharges, are commonly used as "airflow"

cleaners, whereby the cotton is conveyed pneumatically to the cleaner and the air thenceforth is

separated through the screens. Airline cleaners

permit both air and seed cotton to pass entu-ely

through and thus differ from gravity cleaners.

Airline cleaners are principally employed in pneumatic systems, but they may be used advantageously to simplify the equipment or to conserve

space by being placed over the truck runway.

Such cleaners are popular in the High Plains of

Texas and in western Oklahoma as an eft'ective

means for removing sand from cotton and breaking the bolls prior to cleaning.

Extracting units are more effective in removing

burs, sticks, and other foreign matter from roughly

harvested cotton than cleaners. In modern gins.

3 MOORE, V. P., and MERKEL, C. M. CLEANING COTTON AT GINS AND jMETHODS FOR IMPROVEMENT. U. S.

Dept. Agr. Cir. 922, 50 pp., illus. 1953.

FIGURE 9.—Inclined gravit^'-type cleaner installations:

A, With separator in low position; B, with separator and

bypass in elevated position.

even with the best system of cleaners employing

concave screens and beaters, the amount of trash

removed is seldom more than 33 percent of the

total in the seed cotton as it came to the gin. On

the other hand, all of the extracting processes
g TABLE; 1.- Results obtained with cotton that has been harnested and ginned under various eanditions and the fiber dried to moisture contents

I of Jf to 9 percent

Harvesting, ginning, and kii\d of

cotton

Moderate gnin

driers, of ear

damp, liandto 14 perce

tent).

ing, witli

ly-season, g

picked cott

nt moistur

1 to 2

reen or

on (12

e conStandard ginning, witli 2 or 3

driers, of midseason macliinepicked or late-season handpicked cotton (12 to 15 percent

moisture content).

Elaborate ginning, witli 2 or 3

driers, of late-season, handsnapped (above 15 percent moisture content) or machine-stripped

(11 to 14 percent moisture content) cotton.

Ginning and fiber data of seed-cotton fiber dried to moisture content of9 percent

Rough preparation.

Slow ginning rate__

Good pressing

Chokages probabk>_

7 percent

Normal preparation.

Normal ginning rate_

Low grade

Full staple length

Loses weight in storage

High mill waste

Reduced yarn a]jpearanee

Fiber damage possible

Good jiressing.

Increased grade

Full .staple length

Weight constant in storage

Normal mill waste

Good yarn appearance

5 percent

Smooth preparation.

Slow ginning rate

Dithcuit pressing".

Smooth preparation.

Normal ginning rate_

Good pressing

Increased grade

Reduced staple length__

Gains weight in storage

Normal mill waste

Good yarn appearance.

4 percent

Good grade

Full staple length

Weight constant in storage.

Average mill waste

Good yarn appearance

Normal preparation..

Normal ginning rate.

Good jjressing

Smooth preparation.

Slow ginning rate

Difñcult pressing

Good grade

Reduced stajile length

Gains weight in storage- .

Increased mill waste

Average yarn ajjpearaneeSmooth preparationSlow ginning rate

Difficult pressing

Low grade

Normal staple length

Weight constant in storage.

High mill waste

Average yarn appearance._.

Normal preparation.

Slower ginning" rate.

Difficult pressing.

Static problems.

Reduced bale weight.

Improved grade j Improved grade.

Reduced staple length Reduced staple length.

Gains weight in storage Gains weight in storage.

High mill waste | High mill waste.

Average yarn appearance i Reduced yarn appearance.

Smooth preparation.

Slower ginning rate.

Static problems.

Difficult pressing.

Reduced bale weight.

Increased grade.

Reduced staple length.

Gains weight in storage.

High mill waste.

Reduced yarn appearance.

Increased cost of spiiuiing.

Smooth preparation.

Slower ginning" rate.

Difficult pressing.

Static problems.

Reduced bale weight.

Top grade.

Reduced staple length.

Gains weight in storage.

High mill waste.

Reduced yarn appearance.

Increased cost of spimiing.

O

O

2¡

O

o

o

2,

îO
10 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

along so-called carding princii)lcs may remove up

to 40 percent. Large extracting machines may

be used m overhead positions as master extractors

to serve the entire ginning ))attery, oi' snnill

machines may be used as unit extractor-feeders

to supply individual gin stands and to replace

older forms of cleaning feeders.

General trends in the installation of cleaners

and extractors are toward sim|)licity and compactness, with a view to having an adequate a.mount

of cleaning apparatus. For this reason, s])ecial

extractor-cleaner imits are frequently substituted

under the distributor for overhead cleaners and

master extractors.

Modern combinations of overhead cleannig and

extracting machinery for use in districts where

cotton is usualty roughly harvested are shown in

figure 10. In the Southeastern States, the placing

of unit extractor-feeders above existing plain gin

stands is a simple and economical step toward

modernization. Where new gin stands are purchased, it is frequently desirable to obtain huiler

stands and combine them with unit extractors as

shown in figure 10, B. This arrangement is a

popular practice in the central cotton States and

in the western part of the Cotton Belt.

If possible, selection of cleaning and drymg

e(iuipment should be made at the same tirne.

With proper planning, cleaning and dryijig equipment can be installed together more cheaply than

separately.

A recent improvement in cleaning and extracting

is the United States Department of Agriculture

design of a machine for removing sl^icks from

nuichine-stripped cotton.* Its position in a cotton

gin has been indicated in figure 6, and its constructioii is more fully described in Appendix,

figure 38.

Two forms of conveying systems are common to

ginning establishments—mechanical and pneumatic. Conveyor-distributors are \videly em-

])loyed to transfer seed cotton to and from big-bur

or master extractors; pneumatic conveying is usually preferred between driers and cleaners. With

the mechanical system, the seed cotton is also fed

to each bank of feeders and gin stands, and any

* Public patent apiilied for.

Separator Separator.^

FIGURE 10.—Arraiigoment.s of cleaning and extracting machinery in gins that handle roughly harvested seed cotton:

A, Overhead cleaning and extracting units, together with extractor feeders, huUer gins, and lint cleaners; B, bulk

drying and cleaning prior to distriljuting, followed by cleaning, extracting, and feeding at individual gin stands,

together with huiler gins and lint cleaners; C, modern arrangement with bulk feed control, multiple drying, and hnt

cleaning at floor level; and D, multiple drying, cleaning, and extracting at floor level.
MODERNIZING COTTON GINS 11

surplus seed cotton is discharged at tlie overflow,

from which it may be returned to the liandUng

system. Both systems are tlicreforc suitabk^ for

use with many combinations of concUtioning,

cleaning, and extracting machinery. Distributing

systems are further discussed in "the section, Separators and Distributors, page 24.

Feeders and Gin Stands

Plain gin stands have been superseded by

double-rib huiler gins, whose fronts remove appreciable ciuantities of leaves, stems, and minor

items of foreign matter even when elaborate

cleaning and extracting processes have preceded

them. The picker rollers on huiler gins of the

latest models are ecpiipped with lever-shifting

devices, so that tlie position of the roller may be

adjusted to the immediate condition of roughness

in the seed cotton. Gin stands of all-steel construction that are precision built and afford a

superior protection to the cylinders and brushes

or nozzles came into use after 1930.

Inasmuch as the older wooden-frame cotton

gins are difhcult to keep in good condition and

caimot be fitted with late-model fronts or bearins's,

it is advisable to replace them with stands that

lurve l)een nninulactured snice 1940.

Sectional views of feeders of the big-drum and

cleaner-extractor types are shown in fio-ure 11

Largely as a result of I'esearch by the Unitcnl States

Cotton buniTung La))oratories, improvements in

cotton gin stands liave included improved motinoarrangements and increased saw speeds tiiat now

range between 650 and 700 revolutions per minute

Dunng recent years 90-saw stands have been replacnig 80-saw or smaller stands. Improved

shapes of saw teeth have resulted in efficient forms

havnig either sliglitly curved or straight backs,

with number of teeth varying between 264 and

282 per 12-inch diameter saw. When the saws

have been reduced by }U inch from their original

diameter by wear and sharpenhig, ginning capacity is freciuently decreased by 20 percent or

more. The entire saw cylinder "sliould then be

refilled with new saws. For good doffing, tip

speeds of gin brushes sliould be approximately

6,666 linear feet per minute, and air-blast nozzle

doflSng pressures should be approximately 12^

inches on the water gage to give jet velocities up'

to 13,000 feet per minute.

By means of its keen angle grids that shuttle

back and forth beliind the gin saws, a reciprocleaner moting attachment for air-blast gins significantly enhances moting and Hnt-cleaning

lOOO CF.M.

mfO 0VOÍMEAO

FIGURE 11.—Sectional views of feeders: A, Big-drum feeder; 5, large-size oleaner-e.xtractor-feeder with liot-air supply.
12 AGR. HANDBOOK 9 9, V. S. DEPT. OF AGRICULTURE

FioiRE 12.—Sectional views of saw-cylinder lint cleaner: A, Air-blast gin and air-blast lint cleaner; B, brush gin and

brnsli lint cleaner.

actions.* A ]:)ul)lic patent on this attaclimenl

makes it free for use by the piibhe, and workin^i

drawings arc obtainable from the ULSDA Cotton

Ginning Research Laboratorj^, Stonevillc, Miss.

Lint Cleaners ^

Lint cleaners are revolutionary devices for

cleaning cotton in the gin. For best results they

should be operated in accordance with recommended procedures and kept in good repair and

proper adjustment. To obtain maximum grades

and to preserve fiber quality with lint cleaners,

the cotton should be drj^ and the gin stands operated at moderate rates of feed and with loose

seed rolls. Tests have sjiown that the effectiveness of lint cleaners maj^ be reduced by heavy

rates of feed, which in turn cause an increase in

the ncp count of the lint. Lint cleaners have not

replaced seed-cotton cleaners and extractors at

modern gins, but they have been effective in removing as much as 8 percent bj^ weight of the

trash that originally came to the gin with machine-picked seed cotton and could not be taken

out prior to lint cleaning.

5 MERKEL, C. M., and MOORE V. P. AN iMPRf)VED

MOTING SYSTEM FOR COTTON GINS. U. S. Dept. Agr. Cir.

974, 2:5 pp., illns. 1965.

'i STHEDONSKY, V. L., and SHAW, C. S. THE FLOWTHROl'GH LINT-COTTON CLEANER. U. S. Dept. Agr. Cir.

858. 30 pp., illus. 19.50.

MOORE, V. P., and MERKEL, C. M. CLEANING COTTON

AT GINS AND METHODS FOR IMPROVEMENT. U. S. Dept.

Agr. Cir. 922, 50 pp., illus. 1953.

Typical saw-cylinder lint cleaners, shown in

figure 12 and Appendix figure 4.3, use a condenser

or an air-screen separator alieacl of the cleaning

saws to bleed off air conveying the lint cotton

from the gin stand. The manufacturers' recommendations for balancing this air should be

closely followed in order to maintain greatest

effectiveness.

If a lint cleaner uses an air-blast doffing system,

it is important that the gin-stand doffing pressure

be kept low, consistent with good stand operation,

to clean the gin saws and transfer the lint to the

lint cleaner. Minimizing the air to be handled

by the lint-cleaner condenser will in turn reduce

the possibility of backlash in the gin stands.

Pneumatic tjq^es of lint cleaners, shown in

figure 13, are widely used. Manufacturers' recommendations as to air volumes and velocities

should be followed. Leaks in suction condensers

and lint flues must be avoided, and settings should

be maintained through periodic inspection. These

units siiould be regularly cleaned of accumulations

of cotton and foreign material.

It is generally possible to install either the sawor pneumatic-tj'pe lint cleaners in old gins, through

certain modification of drives, the condenser, and

lint flues. Each installation requires a special

engineering layout to obtain the most effective

operation. Accessibflity to all moving or vital

parts of the lint cleaner is always important if

uninterrupted service is to be maintained.
MODERNIZING COTTON GINS 13

j Adjustable

lips

f

High speed

disk cylinder

trash / From gin stand

FiGUBE 13.—Sectional views of pneumatic lint cleaners: A, Air-blast sin and superjet lint cleaner; B, air-blast gin and

air-centrifugal lint cleaner.

In installing lint cleaners, attention to the lint

flue leading from the gin stand to the cleaner is

necessary to insure tliat all inside surfaces are

perfectly smooth. No rough edges of metal or

bolt heads should project into the flue, as they

would cause cotton tags to accmnulate. Bj'pass

valves should be examined to see whether they

close properly. Any tags or lint accumulations

that break loose from pipes or valves and enter

the cleaner can seriously damage the saws and

grid bars.

The interiors of all lint-cleaner condensers and

air-vent flues should be cleaned regularly each day

to insure against chokage and back pressure.

Wherever condensers are used, proper maintenance of their doffing rollers is necessary to insure

satisfactory operation of the lint cleaners. The

rollers should be kept in adjustment and their

flights replaced when they have lost their efi'cctiveness as an air seal. Too much air blowing past

the doffing rollers will disturb the batt of cotton entering the feed rollers, causing chokes at the rollers

and the loss of usable fibers with the lint-cleaner

trash. The revolving separator cages and screens

should be inspected to ascertain whether the surface is smooth, so as to eliminate the possibility of

lint building up on rough spots.

Inspection and maintenance procedures for lint

cleaners should include the following:

1. Saws should be checked daily. Sticks, stems, and

other foreign matter attached to the teeth should be

removed.

2. Saws should be kept sharp and in good operating

condition.

3. Grid bars and air-blast nozzles should be inspected

regularly for alinement and proper clearance. If a brush

is used instead of air blast, the same care and maintenance

should be given it as to the gin stand. For proper doffing,

the brush should mesh with the saw to the depth of the

saw tooth, unless wobble saws are used. In such cases,

the tips of the bristles should barely touch the saws.

4. The trash-disposal unit should receive periodic attention. Conveyor Ijelts should be kept tight, and dropper

wheels should be inspected for wear and damage.

5. All glass inspection doors should be replaced immediately when broken; otherwise, air movement in the cleaner

will he disturbed.

Handling Seed and Trash

Seed and trash may be handled readily by

gravity, belts, screw conveyors, or pneumatic

piping. There are several methods for handhng

seed so as to keep it ptu-e. The belt and blowpipe

types of seed conveying are self-cleaning, but

screw conveyors must be hand-cleaned between

the ginning of diflerent varieties. For other than

single-variety gins, the use of belt or blowpipe

conveyors is therefore desirable where an appreciable quantity of seed is to be saved for plantmg.

' BENNETT, C. A., and FRANKS, G. N. COTTONSEED

H.JLNDLING WITH SMALL AIR PIPES. U. S. Dept. Agr. Gir.

768, 8 pp.. illu.-^. I'.JIS.
14 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

The following convoyinp; dovifcs are among

those now in use:

1. A horizontal, flat seed bolt in a -smooth trough below

the stands, delivering either to an inehned belt or to a

seed-blowing pipe tiirough a vacuum-wheel seed feeder.

2. A horizontal skeleton drag belt operating in practically the same way as the flat belt described above.

3. A reversible horizontal flat seed belt Ijeneath the

stands, operating in one direction to deliver gin-run seed,

and in the other to deliver pure seed, each discharging into

bins or sackers by various means.

4. Two individual conveyors beneath the stands, ginrun seed being handled in the rear system and pure .seed

in the front one—each system having its own lifts and

deliveries.

5. Gravity chutes with hinged covers in front or Ijelow

each stand, diverting pure seed by gravity into funnels and

sacks below, while a standard screw conveyor is generally

used on gin-run seed.

6. Gravity chutes similar to those descrilx'd above but

delivering pure seed into a blowpipe by means of a rotating

vacuum-wheel seed feeder.

W^iere vertical lifts are employed, screw elevators are generally more efhcient and sturdy than

wooden-bucket elevators, whose troubles with

slipping belts and faulty alinement are well known.

In some instances seed and trash may be conveyed

by belts and piping. Conveying seed by air in

small pipes is now the most efhcient and economical method.

Means for disposing of foreign matter from the

cotton gin arc not only desirable but withm incorporated communities may be requu-ed by ordinances and health regulations.

The hazards from dust, fire, insect micstation;

and spreading of certain plant diseases and fungi

must be considered among the problems of gm

trash disposal. Means of trash disposal (see

fig. 41, Appendix) include use of a collection bunker

for hauhng an incinerator for immediately burning the combustible portions of the trash, and a

compost pit for converting the materials into

plant food, or merely blowing all foreign matter

to a so-called bur pile, which should be a safe

distance from the ginning buildings.

To reduce handhng costs when trash is to be

immediately composted or burned, the air discharge from the first cotton unloading fan may be

utilized as a conveyor to the incinerator or pit.

All other trash fans then dehver to a cyclone-collector located next to the gin building, from which

the trash is fed into the conveying hne by means

of an oversize, nonchoking vacuum-wheel dropper

Must be too or more

Colleci-ors to comply

r/ wit-h State laws

FirebrickK^

}/-

I I

' ' Firepot

A

11

11

pipe ¡ I

-/'^'X<^'.Vii^<777

, .Tiles ^ H^ • ^o-^o#o oil;

18 pipe

Note:

For pink bollworm

conhroi, trash fan

should pull from

dropper.

Pressure

blower Pipe size +0 suit

V/ÀtS'y //Ayr//

Push or

pull far>

y//<}7/''\'^/\<v/f

FIGURE 14.—Schematic diagram of a good system for collecting cotton gin trash and pneumatically delivering it to an

incinerator. A different design of incinerator is shown in Appendix, figure 42.
MODERNIZING COTTON GINS 15

(fig. 14) and second fan if quarantine regulations

on pink boUworm apply.

The use of a secondary cyclone-collector for

feeding the incinerator or compost pit prevents

an excessive dispersion of dust. The operation

of any incinerator is subject to some smoke

nuisance, but this may be reduced to a large

extent by utilizing a small-pipe, turbo-blower air

supply to the center of the burning material within

the incinerator (see fig. 42, Appendix). This

makes for more rapid and hotter combustion, like

a blacksmith's forge, and increases the capacity

of the incinerator.

The incinerator shown in figure 14 is designed

to handle approximately 5,000 pounds of trash

per hour. The unit may be either I'ound or

square. If more than 5,000 pounds per hour is

to be handled, an increase in size to 24 by 24 feet,

outside dimensions, is recommended. The superstructure of the unit should be air-cooled to

prevent the intense heat of the furnace from

causing the metal framing to warp and buckle.

A tall smokestaclv is desirable but not essential

to satisfactorjr incineration. It may, however,

enable the ginner to reduce low-level drifting of

very fine ash and some objectionable smoke.

Burning of trash does not bring a profit to the

ginner, except in the vicinitj^ of Lubbock, Tex.,

where the operation is often used as a source of

power and produces caustic alkali solids that have

sales value. The feeding of the edible portions

of the trash to livestock has shown some promise

for mixtures requiring bulk. Composting of the

material to provide a fertilizer or plant food for

spreading on land has been widely tried, but thus

far has not been extensivelj^ adopted throughout

the Cotton Belt.

AIR PIPING AND FANS

Pneumatic sj^stems consume from 50 to 65

percent of all the power required in modern cotton

gins. They also determine whether the ginner is

to experience smooth operation or continuous

trouble. It is of the greatest importance, therefore, to plan, select, and install piping and fans

with a view to economical and efficient operation.

The problems of piping and fans will be more

readily understood Ij}^ keeping in mind that the

flow of air in a pipe in cotton gins is similar to the

flow of water in a pipe. Airflow, however, is

measured in units of cubic feet per minute instead

of gallons per minute as for water. Pressures

within the air pipes are measured in units of inches

of water on a U-tube gage or manometer, rather

than in pounds per square inch. The majority

of cotton-gin fans operate against static pressures

(resistances) below 27.8 inches of water, which is

the equivalent of 1 pound per square inch.

The number, size, and operating rate of gin

stands will determine the required rate of flow of

seed cotton to the gin. This and the layout of the

gnuung establishment should determine the dimensions and arrangcMuent of the pipino- The air

volume needed to overcome the resistance of

equipment and pipes and to supply the gins will

determine what fan capacity is needed.

Table 2 shows average' pipe diameters, air

volumes, and power required at given static

pressures for various ginning layouts. The fio^ures

given are representative only and subjcc^t to

variation because of differences in pressure and

volume frequently encountered in individual

gins.

Alethods of computing requirements for both

piping and fans are explained in the foUowing

two sections.

Piping for Seed Cotton

From 800 to 1,000 cubic feet of air per minute

is usually required at the unloading telescope to

supply seed cotton to each gin stand, depending

on the type of system and the length of suction

piping. If a cotton-house suction pipe is included,

a_ modernized piping layout may be designed to

give the same friction loss and constant volume

from the cotton house as from the unloading

telescope, thus affording a satisfactory conveying

velocity in the largest pipe.

In such a system, the telescope suction velocity

may be maintainecl at 5,000 to 6,000 linear feet

per minute so that smaller piping on this short

run will give the same resitance as the longer line

of larger piping to the cotton house. The selection

of fan size and speed is thus simplified and more

economical operation assured.

Diagrammatic plans of piping for the two systems—with and without cotton-house pipe—are

shown in figure 15. Table 3 gives information on

ranges of ah' volumes, fan-wheel diameters, and

speeds required for satisfactory operation of various sizes of ginning fans. In the cotton-house

system of figure 15, approximately the same

resistances or static pressures are used for both

unloading at wagon and for the cotton house.

Improved types of separators having less leakage

than allowed for in tables 2 and 3 will reduce the

fan speed and power requirements correspondingly.

In these systems, the unloading and overflow

telescopes may be of difl'erent sizes, but where

cotton-house suction and overflow employ the

same piping in part, the full size of the cottonhouse fine should be continued to the separator,

with reduced size takeoff and valve for the overflow connection. Valves in all seed-cotton suction

lines should be placed in a vertical position to

prevent unequal distribution of seed cotton into

the separator. Piping diameter from the separator to the fan should be more than one-half of

the fan-wheel diameter, without reduction into the

fan inlet. In ah cases the diameter of this piping

should be equal to or greater than that for the

seed-cotton suction line.
16 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

TABLE 2.—Average pipe diameters, air volume, and power required at given static pressuresfor various cotton

gin piping systems having SO-saw stands '

Three-stand battery Four-stand battery Five-stand battery

Piping system and static pressure Pipe

diameter

Air volume

Power

required

Pipe

diameter

Air volume

Power

required

Pipe

diameter

Air volume

Power

required

Cotton unloading:

Suction from truck or bin to

separator with free discliarge

(static pressure 12}^ inches)__

Suction from trucl< or bin to

separator but blowing trash

(static pressure, 15 inches).__

Cotton drying:

Suction' through combined

tower and cleaner (static

pressure, 18 inches)

In.

10

10

16

16

16

10

4

C. f. m.

4,000

4,000

6, 000

6,000

4, 500

2,750

400

Hp.

16

20

34

25

18

10

5

In.

11

11

16

16

16

10

5

C. f. m.

5, 000

5,000

7,000

7,000

6,000

2, 750

670

Hp.

19

24

39

33

22

10

10

In.

12

12

16

16

18

12

6

C. f. m.

6; 000

6,000

8, 800

8, 800

7, 500

4,000

1,050

Hp.

22

28

50

Blow-through combined tower

and cleaner (static pressure,

15 inches) 41

Air-blast piping: To nozzles of gin

stands and lint cleaners (static 27

Trash blowing: To cyclone at gin

wall (static pressure, 10 inches)-

Seed blowing: Rotary pumps or

turbo-blower, smalî-pipe s^'stem

(static pressure, 56 inches)

14

15

to the

Pipo diameters and power requirements are shown to the nearest whole number. When resistances arc less than those indicated, the power

e minimum by correctly setting the intake dampers on fans and blowers.

can be reduced

T^gj^j, ¿—Air volumes and velocities, fan size and speed, and power required for operation of various

ginning systems with and without cotton house and with various sizes of pipe for 80-saw stands

Arrangement and size of

ginning s^'Stem

With cotton house:

3 stands

4 stands

5 stands

Without cotton house:

3 stands

4 stands

5 stands

Volume of

air required at

fan inlet

Cf. m.

4, 000

5, 000

6, 000

4, 000

5, 000

6, 000

Wheel diameter of

18-blade

suction fan

In.

Fan

speed'

26

30

33

R. p. m.

1, 620

1,680

1, 720

26

30

33

1,450

1, 560

1,620

Approxi

mate power

required

Hp.

16

20

25

16

19

24

Suction piping

Unloading telescope

Diameter Velocity

In.

11

12

13

10

11

12

F. p. íí¡.

6,060

6, 370

6, 500

7,300

7,600

7,650

Cotton-house line '

Diameter

In.

13

14

14

Velocity

F. p. m.

4, 350

4, 700

5,650

I Average of several makes of 18-blade shrouded fans. Tip speeds up to 1.5,000 feet per minute are considered to he safe.

- "For diaeram of piping, see fig. 15. 3 Fnnivilent length including elbows, .W feet from separator to nose of telescope. , , , , , ,^,

< Equivalent length^ includmg valves and elbows, 15U feet from separator to cotton-house suction point and 50 feet from separator to nose of telescope.
MODERNIZING COTTON GINS 17

Fan discharge

Ginning system

/Overflow

(telescope

I^Wagon telescope

A

Cotton^

house

O

Q-«^Fan discharge

=0

Fan Overflow

telescope

Separator Ginning system

l>^Valve

Valve 2

/Wagon telescope

B

FIGURE 15.—Schematic diagrams of typical cotton-gin

piping systems: ^4, Witti unloading and overflow suction

only; B, with unloading and overflow suction together

with cotton-house piping.

In a pneumatic-elevator system (having no

mechanical separator) the above suggestions will

also apply. However, if no ginned seed is to be

blown by the fan discharge, a cutoff valve of the

butterfly or stove-damper type on the fan inlet

wUl save power by reducing the load on the fan

when the gins are idling.

Where lengths of piping are different from those

given in table 3, the cotton-piping chart (fig. 16)

wUl be of assistance in working out the friction

losses, in order to balance or give equal losses to

the unloading and cotton-house lines.

The following example illustrates how the chart

is used. A 2-stand 90-saw outfit is to be installed

with a 10-inch unloading telescope and suction

line, and with a length (including straight-line

equivalents for all elbows) of 50 feet between the

the nose of the telescope and the valve at the

separator inlet. It should require not more than

3,000 cubic feet per minute, including separator

leakage. It is desired to lay out a system similar

to that in figure 15, B, in which the cotton-house

suction piping wül have 80 feet of straight pipe

381692°—.56 3

and five 90° elbows. The necessary calculations

are given in the following tabulation:

Unloading stwiion line

1. From figure IG, the friction loss per 100 feet of 10-inch

piping handling 8,000 cubic feet of air per ininule is

4.80 inches.

Since length of the unloading suction line is 50 feet,

its loss is 2.40 inches.

Colton-house suction line

2. To balance the loss from the unloading line (first

column), the friction loss of the cotton-house line must

be 2.40 inches.

3. Ecjuivalent lengths of proposed piping as fractions of

100 feet—straight pipe, 0.80; five elbows at 10 feet

each, 0.50; total, 1.30.

4. The loss per 100 feet must therefore be 2.40 inches

divided by 1.30, or 1.85 inches on the U-tube gage.

5. Figure 16 shows that a 12-inch pipe will be needed to

deliver about 3,000 cubic feet per minute with this

friction loss.

There must always be an adequate "velocity

head" to provide an ample flow of air. Velocity

head is a special measure of pressure that will

produce a deshed velocity. It is given in inches

of water at the left of figure 16 to correspond with

the mean velocities shown. It must be counted

in, but is not separately indicated on the readings

of a gage.

In the foregoing example, the dotted line for

1.85 inches of water resistance per hundred feet

of piping intersects the line for 12-inch diameter

pipe (wliich extends diagonally upward to the

right) between the 3,500- and 4,000-feet-perminute diagonal lines of velocity. This is not a

particularly strong suction, but is considered sufficient to warrant the use of the 12-ineh pipe,

which requires a 1-iiich velocity head in order to

obtain a velocity of at least 3,650 feet per minute.

General Rules for Piping

Certain general rules for successful installations

of seed-cotton handling systems have been established after many years of experience. Some of

these rules are:

1. Make the piping as simple and direct as possible by

eliminating unnecessary elbows and valves.

2. For good suction in a seed-cotton pipe, maintain

velocities of 4,000 to 7,000 feet per minute.

3. For blowing trash and seed, the velocity in the pipe

should be at least a mile a minute, and hence the pipe

diameter should be kept l)et\veen 10 and 13 inches. This

does not apply to small-pipe seed-blow systems where the

velocitv is held to approximately 4,250 feet per minute,

while the pressure is greatly increased and the volume of

air is reduced.

4 Piping for cottonseed and seed cotton should not slope

downward in the direction of flow. Downward slopes may

cause chokes.

5. Allowing 45 cubic feet of air for each pound of material, unloading and o\ erflow suction piping should be such
18 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

Volumes (cubic feet pen minute)

o

FIGURE 16.-

<!> x> ^

Pipe diameters (inches)

-Cotton-piping chart, giving friction losses in inclies of water per hundred feet of piping for different pipe

diameters, air volumes, and air velocities.

as to obtain the highest velocity with the required air

volume. A 10-inch suction line is adequate for 3-stand,

80-saw gins, an 11-inch line for 4-stand gins, and a 12-inch

line for 5-stand gins; but for 90-saw gin stands, piping sizes

1 inch larger than for 80-saw units are suggested.

6. For cotton houses, a rembert-type fan is simple and

economical for handling seed cotton, but a standard fan

and separator with correct piping can be employed satisfactorily when used with a belt or screw conveyor in

horizontal houses and with a revolving discharge chute into

bins of octagonal houses. Fire hazards must be avoided

in both sjrstems.

7. The friction loss in cotton piping from the cotton

house to the gin should equal approximately that in the

unloading-suction line, so that a constant speed of the

cotton fan can be selected that will be equally efficient

for both.

Fans

Fans are used in cotton gins chiefly (1) to convey

seed cotton from the truck, trailer, or other conveyance, or from the cotton house to the ginning

machinery, (2) to operate cotton conditioners or

driers, (3) to supply necessarj^ volumes of air to

the dofñng nozzles of air-blast gins, and (4) to

convey seed, hulls, and trash.

Two Idnds of fan wheels—the standard type

and the rembert type—are shown in fignre 17.

Housings or casings for fans should be of the

universal type so they may be moimted from

either right or left and be adjustable to at least

eight positions. Standard-type wheels maj^ be

used in cast-iron casings of various designs, but

rembert-type wheels should be used in a flat,

scroU casing for best results in batidling seed

cotton through the fan.

Standard-type fans are used primarily in the

ginning system and may have plain, flat blades

(fig. 17, A) or shrouded blades (fig. 17, B).

Straight-blade fans have a wide range of interchangeabüity and a long service life not usually

found in multiblade sltrouded wheels. They
MODERNIZING COTTON GINS 19

may handle trash * tlirough the fan wheel, but

rembert-type wheels (fig. 17, O) should handle

neither trash nor seed cotton thi'ough the fan.

Table 4 shows the approximate range in volume

that can be expected from both types of standard

No. 40 (33-inch diameter) fan. Maximum advisable speeds are also shown. The data are

averages of the characteristics of several makes of

fans.

' Refer to Appendix, fig. 41, for quarantine code fanwheel diameters and speeds required for handling trash

containing pinli bolhvorms.

Rembert-type fans are most commoulv employed at cotton houses for cotton conditioners as

well as for unloading seed cotton from trucks to

storage bms. The cone fan designed by the USDA

Cotton Ginning Research Laboratories is very efficient for such purposes, because it provides ample

air vohmies and does not crack seed. For lonoservice the cone of the casing should be lined with

rubber sheeting to reduce abrasion and wear. It

has been an occasional practice to use such fans

for the ginning systems in order to replace separators and standard fans. In manv installations

PiQUHE 17.-Representative types of cotton-gin fan wheels: A, Plain 8-blade wheel; ß, ^'"'O^ded 18-blade whe^^^^^^^

rembert-type wheel, in casing; D, rembert-type cone developed by the USDA Cotton Gmmng Laboratories (pubhc

patent).
20 AGR. HANDBOOK 99, TJ. S. DEPT. OF AGRICULTURE

TABLE 4-—Fan speeds, air output, and power

requiredfor No. 40 plain S-bladejfan and No. 40

shrded 18-blade Jan at 12 inches of static

pressure '

Plain 8-blade fan Shrouded 18-blade fan

Fan speed

(R. p. m.)

Air

output

Power

required

Fan

speed

Air

output

Power

required

1,450

1,500

1,600

1,700

1,760

C. f. m.

2, 540

4,370

0, 100

7, 670

8,500

Hp.

12, 3

18. 5

26. 4

35. 5

41.0

R. p. in.

1, 681

1, 690

1, 720

1, 730

1, 740

1, 762

1, 775

1, 790

Cf. m.

3, 140

4, 250

6, 000

6,500

7,000

7,683

8, 000

8,382

Hp.

12.8

19. 6

23.0

24. 5

26. 0

29. 1

30. 7

32.0

' Data from manufacturers' tables.

electric motors are connected directly witli rembert-type fans. As a general rule, flat-disk,

rembert-type fans of a given wheel diameterseldom

have as much capacity as standard-type fans one

size smaller, running at the same speed.

The so-called high-eíRciency fans have greater

wheel diameters and narrower blades than standard-type fans and are operated at slow speeds.

Their greater first cost is offset by lower power

consumption.

In selecting the proper type and size of fan for a

specific purpose, manufacturers' performance tables should be consulted. Before such tables can

be used, however, it will fli'st be necessary to ascertain the pressure, or friction loss, against which

the fan is to operate and the total volume of air

to be handled.

The total friction loss is the resistance in the

unloading pipe, plus a velocity pressure, or head,'

usually ranging from 1 to 3 or more inches, plus

friction losses in the separator and piping to the

fan inlet, plus any losses in the discharge piping

of the fan. Separators may introduce a friction

loss of as much as 4 inches of water, witli a leakage

of from 1,000 to 2,000 cubic feet per minute. The

piping losses from the separator to the fan inlet

plus those from the fan discbarge may comprise

another 3 inches.

In the system shown in figure 15, friction losses,

including a 4-inch loss at the separator, usually

amount to approximately 14 or more inches.

Manufacturers' tables on 14 or more inches of

static pressure and 5,000 or more cubic feet per

minute capacity would therefore be taken as the

normal basis for fan size and performance.

8 Velocity pressures in inches of water and pipe mean

velocities in feet per minute frequently encountered are,

respectively: 1.2 inches at 4,000 f. p. m.; 1.5 inches at

5,000 f. p. m.; and 1.8 inches at 6,000 f. p. m.

Wlierc fans are to be replaced in an existing piping system, it is advisable to obtain measurements

of air velocity and volume before removing the

old fan. Ttiese will provide a simple and dependable basis for determining the required speed of the

new fan. A metJiod of making such measurements

is described in the section, Air-Blast Systems and

Gages, page 20.

In buying a fan, it is better to specify the kind

of wheel, wheel diameter, number of blades, and

kind of casing (cast iron or steel plate, for example)

than to use vague terms such as "No. 35" or "35-

inch." A No. 15 fan of one company may correspond to the so-called 35-inch fan of another. It

is wise to specify a fan wheel with a diameter approximately twice as large as that of the main pipe

leading to the fan inlet. Such fans do not require

excessive speed in either standard or rembert

types.

Another factor to be remembered in choosing fans

is that decreases in air density with increases in

altitude affect their performance. As an example,

a fan operating at an elevation of 3,500 feet requires a speed increase of about 13 percent to

deliver the same quantity of air by weight as at

sea level.

AIR-BLAST SYSTEMS AND GAGES

The increasing use of air-blast gages is well

warranted. They enable the ginner to keep informed of nozzle pressures during operation, and

thus to reduce energy requirements and maintain

the output of high-quality lint.

Two distinct forms of air-blast gages are available, one for portable use on individual gin stands

and the other for stationary or permanent observation at some accessible place in the vicinity

of the gin.

The portable gage (fig. 18) may be made with

the material shown in table 5. The instrument

board may be of liardwood or softwood, finished

all over, and varnished to prevent warping. The

glass tubing is usually obtainable at drug stores

or supply houses. À^Tiere possible, the sharp

edges of these tubes should be rounded off over

a bunsen burner or gas flame. Straight copper

tubing should be used and the tip finished as

shown in figure 19. The amount of bending required will depend on the make of cotton gin.

The other items are self-explanatory.

Before putting on the dust cap, water or antifreeze solution, colored with dye or red ink, is put

into the U-tube with a medicine dropper

The level of the Hquid in both tubes should be

brought to the zero line of the scale. If the

liquid evaporates, or if difficulties in filling the

U-tube prevent bringing the liquid to the desired

level, then the scale may be moved to the desired

position by means of the slots and adjusting screws.
MODERNIZING COTTON GINS 21

TABLE 5.—Material required for a portable air-blast

gage

Number

required Material Description

1 Wood Instrument board, Yt by 3

bv 24 inches.

2 Glass Tubing, Yi inch inside diameter bv 22 inches long.

1 Copper Tubing, \i inch inside diameter bv 24 inches long.

1 Rubber Tubing, for bottom of U, }:!

inch bv 4 inches long.

1 Rubber Tubing, Vi inch bv 60 inches.

1 Wood or metal.. Scale, in inches.

4 Sheet tin Straps, to fasten glass tubing.

8 Metal Screws for clips, to suit.

2 Metal Screws for scale, to suit.

8 Felt Packing strips for glass and

straps.

Shellac For cementing rubber tubing to glass or copper.

1 Paper Dust cap with pinho es.

Paper cap—_

with pin holes

Inch scale

Board —

Zero line

Rubber

tubing

'A"''60"

Glass

tubing

'/4V22"

Rubber,

tube — Bend

to suit nozzle

FiGL'RE 18.—Portable air-blast gage.

For airtightness, it is best to shellac all joints

between rubber and glass or copper before slipping

the rubber tubing into place.

To use the gage, first see that it is plumb and

that the surface of the liquid in both glasses is at

Direchion

FIGURE 19.- -Positions of tip of copper tube for checking

air-blast nozzle pressure.

the zero limit. Then hold the tip of the copper

tubing so that it almost touches the nozzle of the

air-blast flue, as shown in figure 19. The air

blast must blow into this tip in a straight fine.

The liquid in the adjacent leg of the U-tube will

then fall below the zero line, while that in the

opposite leg wül rise an equal distance above it.

The distance between the two levels of the

liquid in the U-tube gives the pressure reading.

For instance, if the liquid rises (>]i inches above

the zero point in one leg and falls 6K inches in

the other, the pressure at the nozzle is 13 inches

of water.

Readings at both ends of a gin stand on its airblast nozzle should be the same, and all readings

at the various nozzles in a battery of stands should

be reasonably alike. If the nozzle pressures are

too low for'satisfactory operation, it does not

necessarily mean that tlie air-blast fan must be

speeded up. Other mechanisms in the ginnmg

plant mav be at fault. The distributmg partitions that supply the nozzles may not be au-tight,

may be choked up, or mav be loose at some point

near the nozzles. Tlie air-blast pipmg may also

be leaky, may have too many bends and restrictions, or may be choked vnÚ\ foreign matter.

The nozzles mav be warped or damaged, and they

may not be parallel to the saw cyhndors or set at
22 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

the correct distance from the tips of saw teeth.

This position depends upon the angle at which

the air blast is intended to blow against the saw

teeth, which varies with tlie make of gin.

As shown in figure 19, the clearance between

nozzles and tips of saw teeth is usually measured

at c. This is taken on the curved or flat surface,

d, below the nozzle opening. It is advisable to

adjust this distance to suit the pressures, atmospheric conditions, and kinds of cotton handled.

When an old fan is to be replaced in an operating system, actual readings with an air-blast gage

will provide the most reliable measure of the total

load against which the fan must operate. Such

readings should be taken before the old fan is

dismounted. To make this test, two Ke-inch

holes wath smooth edges should be drilled into the

pipe, one near the fan intake and the other near

the discharge. Readings can be made by removing the copper tube from the gage and pressing

the open end of the rubber tube over the hole.

A test should be made at each of the holes and the

two readings added to a velocity head of 1 inch

to show the total load on the fan. Manufacturers'

performance tables will show the correct fan size

for the pressure load tlius found and the horsepower requh'ed to propel the fan.

Lock bolllfôl

Solid point

0.02"holes

both sidesX

^cn OOP

J ,"L 6'^

-Band

[Air flow to gin s+ands Soî*—^-

Soldered'

4 Copper tubing -

-Static tube

FIGURE 20.—Details of static tube and installations.

The Stationary gage (fig. 20) is identical with

the portable one, except that the tip 6 inches of

the copper tube is bent at a right angle, the open

end filled with a pointed plug, and three evenly

spaced holes, 0.02 inch in diameter, are drilled

through the tip arm of the tube.

This copper static tube sliould be mounted at

the end of the air pipe, and it is essential that the

tip arm be centered in the air pipe and pointed

toward the fan, that is, into the air current. For

this mounting a longer rubber tubing is usually

needed than for the portable gage. Sometimes

the rubber tube is dispensed with and the metal

tube run to the gage proper, but rubber tubing

probably withstands vibrations longer without

leaking.

Air-blast nozzle pressures can be readily controlled by changing the area of the fan intake, and

tiie stationary air-blast gage should be positioned

so tliat pressures may be observed while adjusting

the control device. Figure 21 is a sectional view

through fan intake and screen box, showing the

air-blast pressure control devised at the ginning

laboratory. This arrangement gives the gmner

fingertip control at all times without the necessity

of changing fan speed. On sunny days with dry

cotton, the air-blast pressures at sea level may be

reduced as low as 10 inches on the water gage;

damp weather and wet cotton may necessitate a

higher pressure to get the best ginning.

Wliere a shde damper is used instead of the cone

valve on the intake pipe, it should be placed as far

away from the fan as possible, to minimize cavitation and air eddies that tend to prevent uniform

entrance of the air into the fan housing. It should

also be borne in mind that slide dampers do not

regulate air volume in exact proportion to the size

of the opening. In other words, a half-closed

damper only reduces the air volume to 65 percent

of that admitted at a full opening. Adjustment

of the damper while observing the air-blast gage

mil, however, enable the ginner to obtain the

desired pressure for best operation.

If it becomes neccssarj^ to speed up an air-blast

fan, it is important to remember that capacity

varies directly with the speed, that pressure varies

with the square of the speed, and that power varies

\\'ith the cube of the speed. Suppose, for example,

that an outfit of three 90-saw stands is supplied

by a fan operating at 1,404 revolutions per minute,

with 11.7 horsepower, and delivering 3,868 cubic

feet of air per minute with a pressure of 11 inches

on the gage. Speeding up the fan to 1,520 revolutions per minute increases the power consumption

to 14.8 horsepower, the pressure to approximately

13 inches, and the delivery of air to 4,187 cubic

feet per minute.

These fan relation ratios maj^ be stated as

follows :

Original volume_Original speed

Final volume Final speed

Original pressure

Final pressure

Original speed squared

Final speed squared

Original horsepower _Original speed cubed

Final horsepower Final speed cubed

The air-blast fan is, at best, a rather inefficient

pump. Its intake should therefore be arranged so

that air mil flow smootlily into the casing.

Discharge piping should be as simple as possible.

Control of volume and pressure is much more

economical on the inlet than on the outlet of these
MODERNIZING COTTON GINS 23

To gin stands —-=---*-ñi

Screened intake box

I 24 Intake

Static tube-^'^:

Conee valvel

I /-ß Crank

-No. 2^ gage ¡

FIGURE 21. -Features of the air-blast fan-intake control and gage designed by the USDA Cotton Ginning Research

Laboratories.

fans, and for this reason it is not good practice to

insert any dampers in the fan discharge.

GIN-MACHJNERY AUXILIARIES

The profitable operation of a cotton gin depends

in part on such auxiliaries as power units, bearings,

belts, and pull«ys. The}' should therefore be

selected with care.

'ower Units

The principal characteristics desired in cottongin power units are constant speed, ample capacity

to handle overloads, durability, and cheapness in

operation and maintenance. The most common

sources of power are electric motors and steam,

diesel, gas, and gasoline engines. Each has

significant advantages and disadvantages.

Several factors need to be considered in selecting

a power unit for a given installation. Among

these are: Amount of power required, first cost of

the equipment, cost of fuel or electric energy, cost

of lubrication, kind of labor needed, expense of

niaintenance, probable lengtli of life, and decrease

in power capacity resulting from use.

A safe engineering method of estimating total

nominal horsepower needed from engine or motor

in a modern cotton gin is as follows: Allow for

each gin saw (a) for hand-picked cotton, 0.45

horsepower; (6) for machine-picked cotton, 0.93

horsepower; and (c) for machine-stripped cotton,

the roughest type, 1.25 horsepower. Thus, a

three-stand 80-saw (3/80) cotton gin for (a) would

need 108 horsepower; a 4/80 for (6), 300; and

a 5/90 for (c), 563 horsepower.

Tlie amount of electrical energy required wdl

vary considerably, depending on how constant and

intermittent loads are handled and upon the

extent of the use of fans and other accessories. In

electrically operated gins, it is liighly advisable to

carry the various loads " of intermittent work of

pumps, presses, and seed loading with sepai'ate

motors rather than from the main motor.

Electric-power companies usually give consultnig

and testing services to their patrons.

Steam gins are decreasing in number, because

they are not conveniently adaptable to intermittent and prompt service and because supphes

1» Refer to Appendix, table 6, for amount of horsepower

needed for various ginning units and gm batteries.
24 AGR. HANDBOOK 99, U. S. DEPT. OF AGRICULTURE

of cheap fuel are disappeariiio;. Furthermore,

some State regulations are increasingly sti'ingent

ill that steam boilers are now subjected to periodic

inspection and licensed operation. However,

modern steam engineering has made such rapid

improvement in construction and practices that

large commercial gins might obtain very effective

and economical installations. Where steam is

available for ginning cotton it has the added

advantage of behig on liand for conditionhig and

sterilizing equipment and for extinguishing fires.

Diesel, gas, and gasoline engines have mucli to

commend them for the seasonal service of cotton

ginning. In selecting such engines the purcliaser

sliould allow for a liberal margin in power over

that which is actually required. Most manufacturers now list their engine ratings at the maximum

power produced when tlie engines are new, and the

purchaser should bear in mind tliat the capacity

will decrease with service.

'ower Transmission

Ball or roller bearings should be substituted

wherever possible for friction-type bearings because of numerous advantages. All frictionless

bearings must be carefully guarded against damage from grit and dust, and approved commercial

t^T^es designed for such service should be selected.

The alinement of shafting and bearings is important to the uninterrupted and economical operation of any gin, and tliis necessitates suitable

pedestals or otlier anchorages for the bearings.

For 2-story gins, concrete pedestals are desirable

on the gro\ind floor; but for 1- or l^-story gins,

adjustable iron floor hangers are frequently preferable. Where the shafting is built up of separate

Fir.uRE 22.—Safety shaft, couplings: .4, Marine type; B,

flange type; C, flexible-chain type.

lengths coupled together, it is much better t^iat

tlie drive should be made at the center rather than

at one end so that torsion and breakage may be

minimized. C'ouplings sliould be of the safety

type shown in figure 22.

In installing new shafting as many belts and

pulleys as possible sliould be eliminated, because

they constitute sources of expense, trouble, and

power loss. While flat belts of adequate center

lengths are about as efficient as V-belts, properly

selected V-belts make very neat, safe, short drives,

and under certain circumstances are satisfactory

for right-angle drives.

Either flat or V-belts must be selected with

maximum capacity in excess of the actual load to

be propelled. It "is far better to have oversized

flat belts or a few extra V-belts in any drive than

to face the delay, expense, and possible damage

that may arise through the use of undersized belts.

C'omposition beltings of various kinds may be used

for seasonal service, but the greatest economy docs

not necessarily lie in the cheapest belt. The duty

of each drive should be carefully considered in

deciding on the kind, capacity, and other specifications of the belt.

Separators and Distributors

The air-handling systems in cotton gins are

usually operated in conjunction with separators,

pneumatic chutes, distributors, lint flues, and

condensers. The general requirements for the

seed-cotton suction and air-blast piping have

already been discussed. The allowance of 800

to 1,000 cubic feet of air per minute per gin stand,

previously made for the unloading system, does

not include an estimated 1,200 or more cubic

feet per minute for air leakage and losses at the

piping joints and separators, which frequently

have faulty vacuum wheels or poorly fitted distributor seals. Improved forms of separators now

on the market employ revolving screens and vacuum wheels that handle much damper and trashier

cottons with lower air losses and fewer chokages

than will older types wdtli stationary screens.

The working width of every separator in a cotton

gin should equal that of the cleaner or hopper

upon which it is placed, and the free area of its

separating screen surfaces should be more than

double that of the suction pipe to fan.

Various types of modern separators are shown

in figure 23. Separators with revolving vacuum

wheels have proved superior to those depending

on a belt distributor with solid flaps to maintain

an air seal. A vacuum wheel is essential when

beltless forms of distributors are used, or when

one separator is used for two purposes, as in several

kinds of modern drying installations.

Distributors of various forms have comprised

the backbone of ginning outfits since the introduction in 1888 of air piping for handling seed cotton.

The marked improvement in separators that began
MODERNIZING COTTON GINS 25

Airtight casing and stationary

perforated plate screen

Cotton inlet

Suction

fan

at either

end

Vacuum whee

dropper

Airtight casing and rotating

screen^ with double seals

Cotton inlet

C

Suction

^to fan

at either

end

Cotton

'ä"'^ discharge

Right

Cotton

discharge

and left hand end compartments

each with rotating disks and

wipers

To suction

fan from either

end of casing

Vacuum wheel

dropper

Revolving screen cage with

flashed ends open to suction

from

both ends

Cotton

discharge

Vacuum wheel

dropper

FIGURE 23.—Modern types of separators: A, Stationär}' curved screen with wiping reel; B, revolving cylindrical screen

with trash conveyor; C, vertical double-perforated disk with wipers; D, revolving drum screen.

about 1928 was accompanied by the immediate

development of better distributors—the principal

forms being those in all-steel design of screw and

gyrator type to replace belt and pneumatic-elevator distributors. Screw distributors or conveyors

are on the market with both single and double

flights, ranging usually from 10 to 16 inches in

diameter and making from 100 to 150 revolutions

per minute in a sheet-metal trough, in the bottom

of which are pivoted change-bale valves to control

the feeding of units beneath. Gyrator distributors incorporate a tedding or kicking action

through spring-steel wh'es for moving the seed

cotton along a sheet-steel trough to the change-bale

valves and overflow.

Modern distributors require little attention

beyond periodic lubrication, are rigid and selfalining to a great degree, use less power than belt

distributors, and reduce fire hazards.

Lint Flues and Condensers

Lint flues may be located either above or below

the level of the operating floor in a cotton gin, as

shown in figure 24. Although the majority of lint

flues are above the floor, in some recent instaUations lint flues have been placed below the floor to

conserve space.

When properly installed, either dust backs or

cleaning screens connected with condensers have

proved a satisfactory aid in removing pin and

pepper trash from the ginned lint. They should

be cleaned daUy, however, and kept in first-class

condition.

The maintenance of proper static pressures

in lint flues is very important, because too much

pressure will produce backlash and its attendant

troubles, especially if the condenser is not large

enough. Lint-flue pressures should not exceed

K-inch of water for bnish gins or ^-inch for ausblast gins. Where ginners omit some of the gm

stands in order to begin their operation of a new

gin, it is desirable to obtain the proper size of lint

flue for the full number and instafl the stands

nearest the press first, so that extensions ot the

lint flue can be made as additional stands are

installed.
26 AGR. HANDBOOK 99, U. S. DEPT. OF AGRICULTURE

FIGURE 24.-Installation of lint flues: A, Above operating floor; B, below operating floor.
MODKRNIZING COTTON GINS 27

FIGURE 25.—Conrienscrs: A, Up-draft ; and B, down-draft.

All-steel condensers may now be obtained for

either up or down discharge, and, when of adequate

size and properly installed, should be little affected

by prevaihng winds if properly shielded by dust

caps or dust shed. Diagrams of typical up-draft

and down-draft blow-type condensers are shown

in figure 25.

Modern cotton gins are making use of suction

condensers for handling fiber from lint cleaners

and roller gins. They are readily adaptable to

all kinds of gins and have several advantages ovei'

blow-type condensers by eliminating backlash and

giving a more easily controlled, uniform batt.

Presses, Trampers, and Pumps

The trend in modern cotton-gin presses has been

toward all-steel construction, hydraulic pressing,

mechanical tramping, and toward standard-density gin compressing," where the bales move over

long distances directly to consuming mills. Doublebox types have supplanted most of the single-box

presses in all except a few of the older small gins

and are on the market in up-packing and downpacking designs.

" BENNETT, C. A., HARMOND, .J. E., and SHAW, C. S.

STANDARD-DENSITY COTTON-OIN PRESSES. U. S. Dept.

Agr. Cir. 733, 16 pp., illus. 1945.

Hydraulic power for pressing has to a large extent replaced screw power, because it is simpler

and more powerful and it eliminates shafting

drives with clutches. With it, presses are readily

adaptable for either up-packing, such as is usually

found in 1 %- and 2-story gins, or for down-packing,

as found in 1-story gins where the bales are tied

out almost at ground level.

Hand-controlled trampers are obsolete; and few

steam ones are being purchased, although years of

experience have proved them dependable.

Modern double-box presses have departed from

the down-swinging doors that require counterweight. Instead, improved side-swinging doors

with hand-wheel locks and other safety attachments are used.

The form of hydraulic pump used in modern

gins depends largely on the kind of power used.

It may be a motor-driven individual unit or belted

to the main-line shaft. As a rule, triplex pumps

and new forms of rotary pumps are most popular

))ecause of their smooth operation and freedom

from trouble. Piston pumps may be either vertical or horizontal and may be provided either with

tight-and-loosc pulleys or V-belts, so that they

mav run steadilv or idle between bale pressing.

It is generally advisable in motor-driven gms
28 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

FIGURE 26.—Motor-driven hydraulic pump.

to operate the press pump with a separate motor,

so that variable peak loads are not imposed upon

the main motor and so that power consumption

may be reduced during periods when the pump

is not needed. Figure 26 illustrates such a pump.

Scoles for Trucks, Bales, and Seed

Methods of weighing seed cotton, seed, and

ginned lint vary widely in different sections of the

country. Some gins employ only one set of truck

-scales for weighing seed cotton and seed. Others

use truck scales to weigh the incoming loads of

seed cotton, another scale to weigh outgoing loads

of seed, and yardarm scales near the press to

weigh the bales. The most modern installations

employ (1) a truck scale for weighing incoming

loads of seed cotton and outgoing loads of seed;

(2) platform or yardarm bale scales located adjacent to the press; and (3) special seed scales

located between the gin stands and the press so

that the weight of seed per bale can be obtained

during the ginning process. Figure 27 shows the

method of installation of a modern seed scale in

a single-story gin. After the seed has been weighed

in the seed scales, it is conveyed by ah, augur, or

lift to wagon bin, seed storage, railroad car, or for

special treatment, such as sterilizing and delinting.

Moisture Restoration and Treatments

Continuing research at the Cotton Ginning

Research Laboratories of the United States Department of Agriculture is producing methods and

apparatus for regulating the moisture content of

the fiber to optimum amounts for each stage in

the ginning processes.^^ Better cleaning results

have been evidenced when the moisture content

of the fiber of seed cotton is approximately 5 percent or less, while gin stand operations require

approximately 7, and pressing upward to 9 percent.

(See table 1.)

Artificial or natural drying usually meets the

cleaning needs, and approved misting nozzles over

the gin lint slide supply satisfactory regulated

quantities of wetting agent solution to condition

the freshly ginned fiber for sampling and pressing.

Methods for the desired 2 percent addition between cleaning and ginning are now undergoing

tests and further investigation.

EXAMPLES OF MODERNIZATION

The essential features of a modern gin and the

improvements that can be made in selection of

bulk feed controls, driers, cleaners, extractors,

distributors, feeders, gin stands, and lint cleaners

have been discussed in connection with figures

6 to 11, inclusive, in which figure 10 gave diagrams

of elaborateh^ equipped cotton gins.

The essential mechanical steps in processing

" Refer to Appendi.x, fig. 40, for diagram of lint slide

misting system.
MODERNIZING COTTON GINS 29

cotton, summarized from tliousands of tests and

sample evaluations, are listed in order of performance in the tabulation that follows. The "workflow" is itemized separatelj^ for processing of clean

and elaborate arrangements for hand-snapped

mechanically stripped cottons.

The relationsliip between banks of gins power

overflow, and press has varied from the old standClean hand-picked

1. Bulk drying, usually one unit, with feed control.

2. Bulk cleaning, also made uniform bv initial feed control

of 1.

3. Distributing to banks of gins.

4. Regulated feeders.

5. Ginning.

6. Discharge of fiber, seed, and foreign matter.

7. Packaging and pressing.

Rough or mechanized harvest

1. Controlled bulk feeding.

2. Controlled bulk drying in stages.

10.

11.

12.

Green boll and rock trap with magnet.

Controlled bulk "opening" cleaning, .5 to 7 cylinders

Controlled bulk major extracting.

Controlled bulk "finishing" cleaning, 7 to .30 cylinders.

Distributing to banks of gins.

Regulated drier-extractor-cleaner feeders.

Ginning.

Lint cleaning.

Discharge of fiber, seed, and foreign matter.

Packaging and pressing.

hand-picked cotton and of rough- or machineharvested cotton and excludes accessory operations, such as weighing, blowing, pumping, and

generating of power.

Figures 28 to 31 more fully illustrate, by line

diagrams, examples of modern cotton gins, from

the minimum for hand-picked cotton to the

FIGURE 27.—Seed scales employed in a modern cotton gin.

arc! plan shown in figure 32 to that of a so-called

reverse setting shown in figure 33.

The machinery diagrammed in figure 31 is also

shown on the plan of figure 33, to indicate how

the major units are kept at ground level. Such

a modernization permits optional use of all

"armex" machinery, so that any kind of cotton

harvesting can be handled economically and with

power saving on machine-picked or clean handpicked cottons.

Need for improvement in gin-building construction has long been recognized; marked advances

have been made in recent years. Typical old-time

wooden and sheet-iron 2-story gin buildings are

shown in figures 34 and 35. Some of the later

gins also have gable ventilating fans to reduce

overhead dust and collections of unsightly fly

fiber. The buddings are now of greater width

and height than formerly, as shown in figure 2.

Progressive ginners find it profitable to have

adequate facilities for storing seed cotton in buildings or trailers before ginning and equipment for

handling the seed cotton with a minimum amount

of labor. An inadequately equipped old-style

rectangular seed-cotton storage house, a modern

octagonal sheet-metal house fitted with pneumatic

unloading system, and modern rectangular and

octagonal houses equipped with a rembert-fan

assembly for unloading are iflustrated in figure 36.

MAINTENANCE OF GINS

Lubrication

Good lubrication prolongs the Ufe of the moving

parts of cotton-ginning machinery.

The value of a lubricant depends on its filmforming capacity at any operating temperature as

well as on its viscosity; hence, oils of the highest

viscosity are not necessarily the best lubricants.

It is advisable to select each lubricant with a view

to its viscosity and film-forming capacity under

the specific conditions to which it mil be subjected

in use The lowest viscosity oil that wifl maintain
30 AGR. HAXDBOOK 99, U. S. DEPT. OF AGRICULTURE

To unioadinâ

fan No. 1

Separahor

¿-*-^From hruck or bins

Separahor-^ _ Power saving funnel

Heater

Extracfor

feeders

Gin sfands

__JnvJ

FKURE 28.—A 3- to 5-staiid gin for hand-picked cotton.

an unbroken oil film on the bearing surfaces is

usualty best, because oils of greater viscosity consume more power than necessarj^ in retaining the

film and in overcoming the internal resistance of

the oil itself. The value of greases likewise depends on the pressures, speeds, and temperatures

of the operating parts, as well as on their body

weight and apparent greasiness. Greases are

usually more economical lubricants than oil.

Other things to consider in lubrication are the

location and types of the oil cups or grease plugs.

Some bearings are not accessible for greasing or

oiling except when the machine is idle, and these

bearings should be of a type that will hold enough

lubricant to last for some time. Bath or ringoiling bearings are superior to friction-type bearings, because they have ample reservoirs and do

not require constant attention. Roller or ball

bearings require still less attention, and the savings

on power will usually more than pay for their

installation.

The use of good grades of oil and grease saves

money. Breakdowns and hot boxes caused by

inferior lubricants frequently result in unwarranted

operating expense and time loss.

Lubrication charts are now generally available

from most oil companies, to aid in tiie selection of

oils and greases for various purposes. These

usually indicate that sliafting and machinery operating at normal temperatures and moderate speeds

can use mineral oils with or without a low percentage of neutral animal or vegetable oils. In

general, the heavier the machine, the slower the

speed and the greater the viscosity recommended.

For ball bearings and chain drives a rather thick

nonrunning oil or grease is necessary. Generally,

a No. 2 grease can be used for ball bearings wherever a light or medium oil is specified, and stifïer

or bigli-temperature greases can be substituted for

heavy or extra-heavy oil. For good operation,

greases must iiave the same temperature ranges as

the oils for which they are substituted. Bearings

of the babbitt and sleeve tj'pe usually operate best

mth oils, while greases are preferable for ball and

roller bearings for normal service up to 3,600

revolutions per minute. Periodic cleaning and

renewal of lubricant are essential for all types of

bearings.

Higli-speed sleeve bearings for motors require

thin lubricating oils, and if the bearings are of

ample size pure mineral oils may be used to

advantage; but if the bearings tend to run hot, it

may be necessary to use a special lubricant that

contains about 10 percent of "fixed" oil to minimize wear \vithout increasing friction.

The approximate quality and properties of most

lubricating oils can he determined without using

any special testing apparatus. Impurities may be

roughly detected by smearing a piece of writing

paper with oil and holding it against the light;

the blot will be ec^ually transparent tliroughout if

there are no impurities; otherwise, solid particles

will show. Another method is to dilute the oil

with kerosene and then filter it tlu'ough filter
MODERNIZING COTTON GINS 31

paper, which will catch any solids or impurities.

To test for acids, some of the od may be placed in

a bottle and copper oxide added. If the oil

retains its original color, it is free from acids; but

if there are acids present, the color will become

greenish or bluish. Another simple test for acid

is to drop some of the oil on a piece of clean bright

sheet copper or sheet brass, and examine it a week

later. There will be a gi'een spot on the sm-faco

of the sheet if the oil contains acid. It is important to consnlt the manufacturers of the bearings

if any doubt exists as to the best lubricant to use.

Repairing

The ginner should make preseason preparations

for first-class operation, including cleaning and

inspection. The best time to do this is at the

end of the preceding season's run, before he forgets

the troubles recently encountered.

Certain operating and maintenance practices

are vital from a ginner's standpoint. First

among liese is to have a clean gin, because it is

profitable to the owner and tends to eliminate fire

hazard and many mechanical troubles At the

l)cgnnnng of the season and frequently thereafter

the gnnier should clean the plant, and it should be

left^clean when the last bale has left the press box

The old-style distributor and its belt frequently

cause trouble. Wooden gin buildings may settle

or l)ecome warped, and if the distributor is rigidly

bi-aced to the walls it may be pulled out of*'line

and become a pair of snakedike boxes in which the

upper box serpentines in one direction and the

lower box in the reverse direction. The weight of

cleaning machinery on the distributor may still

further aggravate this twist and misalinement.

These factors cause the paper pulleys to wear off

on one part faster than elsewhere. The spikes of

the belt in turn are ground off on the underside of

the belts when the pulley grooves disappear, and

the spikes may fall into the machinery.

Separator

From truck or binsDistributor

Hot

air

Extractor

feeders

Gin

stands

FIGURE 29.—A minimum gin for spindle-machine-piclvfd cotton.
CO

to

Separator

Optional

Feed conlrol

From truck -ET

overflow

Separator

Distributor

^Cleaniná and

extracting units^

Hot air^ / raleaners^^-^ NTK

Extractor

feeders

Gin stands

>

o

>

O

Cd

o

o

?1

o

H

'V

O

>

O

a

Ö

d

H

cl

w

FIGURE 30,—An alternative 3-stand mininuini gin for spindle-inaehine-pieked cotton.
MODERNIZING COTTON GINS 33

SeparatorNo.l hea+er-

'Hot air and damp coth)

Valve -»"

Drier

Separ-^

ator

Bulk Peed

. Contro

Rock I Stick

P\j

and A

boll 1

trap"\|l

( twin)

from

trash-^

Distributor

Hot air

Extractor

Feeders

Gin

stands

FIGURE 31.—An elaborate arrangement for 4 to 5 90-saw stands with bulk feed control, multiple drj'ing, cleaning, extracting, ginning, and lint cleaning.

Separator,

Overhead cleaners

Drier and exfracl-or

JX

Distributor

Ppvyer

Fans

r^fFZFEZfEI 3^ %

Gin stands Press deck

Dust" house

-A Bale dock

Près 'P.

Pump>.^

Truck shed Scales

FiGUEE 32.—Floor plan of old-style cotton gin, with power drive between gins and press.

__ I
34 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

Driers Ground floor cleaners Dusthouse

V. and extractors T'X ^^le dock

-^„2^, ^ ^-^ ^-/,

Power,

fans and

heaters

^ B ^^

^Leaner

^-Separator

Overflow. Pressn Pump

Distributor^ Gin stands) Seed'scales f:

_ J

Truck shed ! OL(3itr5_ Scales j

FIGURE 33.—Floor plan of modern cotton gin, using reverse setting so that overflow and seed scales are between stands

and press, while power, heaters, and fans are in closed compartment at far end.

-4 ß

-il'^i I î|

lii'

^^I^^PÄ

0|j¿3 'S

iSlísaií«.- - ^ *"

FI(;L'RE 34.—Cotton-gin buildings: A, Old-type wooden construction; B. brick: C, hollow tile; D, concrete.
MODERNIZING COTTON GINS 35

^^ l^^BE?'—< .

FIGURE 35.—Cotton-gin buildings: A, Old-type 2-story steel-sheathed building; B, i;{>-story steel siding on wooden

framing; C, all-steel, inside and outside with cantilever wagon shed; D, all-steel inside and outside, with 24-foot

plate and high roof.

FIGURE 36.-Seed-cotton storage houses: .4, Rectangular, without unloadinii faeiUlies; ß,' ' ^otangailar ^.ith rem^^^^^^^

type fan for unloading; C, octagonal, with rembert-type fan for unloadnig; D, specialized type, usuig silos and um«ay

protected by roof.
36 ACH. HANDBOOK 99, U. S. DEPT. OF AGRICULTURE

Supports and fastenings of all overhead macliineiy slioidd be kept tight.

The eleaniug screens in cleaners and exifactors

need cheeking. Screens too close to the cylinders

may cause "machining" of the cotton, and, if too

far away, they may cause "roping" and rolling.

Extractor saws or teeth receive severe abuse from

rocks, sticks, and foreign matter. These teeth

should be realined and kept in good shape.

The feeding mechanism that governs the rate

of feed into the system and stands may need

adjustment, operating arms may l)e sprung, pinions may be worn, or other repairs and replacements may be needed.

The gin stands themselves may be overlooked,

unless they have l)een contijuially inspected. The

saws must be sharpened as often as the work in

any particular locality requires, which may range

from once per 100 bales to once per 400 bales per

gin stand. In gumming and filing gin saws, the

pitch and concentricity must be maintained as

close to the factory setting as possible. Pitch of

the saws maj^ be checked by using the gages or

gin-saw segments fumished by the manufactm-ers.

If neither of these is available, the leading edge of

the saw tooth shoidd be made to pass through the

ribs parallel with the surface of the ribs or with

the point of the tooth very slightly in advance.

Even the best filing and gumming machines made

are not automatic; they require careful setting-up

and operation. With either plain gummers or

combined gumming and filing machines, gin-saw

teeth are tapered on the sides so that the tips are

about one-half as thick as the saw disk, or base

of the tooth.

Ginning ribs may become so badly worn that

seed will readily pass through the rib space or slot

along with the hnt. For efficient ginning, ribs

should have clean, straight edges with the sharpness barely removed, and the saw slots should not

vary more than 0.02 or 0.03 of an inch from the

standard width. Repairs to gin ribs consist of

(1) inserting new segments in a cutaway socket

in the rib; (2) welding new material upon the worn

spots to build up the rif), followed by grinding to

correct dimension and shape; or (3) covering the

worn surfaces with hardened plates of suitable

width and minimum thickness to give well-defined

edges to the ribs once more. Improper saw-rib

relationship, which produces dragging of saws

against the ribs in one or several stands of a gin

plant, interferes with the production of lint of

uniform quality.

Defective brush cylinders or improperly adjusted air-blast nozzles are sources of damage to

the lint. If the bristles of the brush are liadly

worn or the brush has shifted from its rcquiied

relationship to the saws so that effective doffing

of the fibers from the saws of one or several of the

stands is not obtained, some of tlie fibers engaged

by the saw teeth will again be carried back through

tlie outer rib and roll box. Thus, nappy or poorly

pi'cpared lint may result, particidarly with damp

or wet cotton. "^ Brushes should be protected

from dampness, vermin, and rodents, and they

should be refilled when necessary and then carefully balanced. Ball-bearing balancing rigs or

knife-edge balances may be homemade by the

ginner if he is familiar with ways and means for

such work. Heavy wear of brushes sometimes

occurs when they mesh too deeply into the saws

or wobble sidewise. If entire brush assembhes

ai'e badly damaged, it is advisable to have them

reconditioned at the factory or a repair shop.

Air-blast gins with nozzles restricted by accumulations of foreign matter and rust may produce

defective samples somewhat in appearance like

those from brush gins in poor condition. Airblast nozzles require periodic adjustment to

provide adequate doffing of the lint from the saws.

The nozzles should not only be given occasional

inspection to insure correct position and freedom

from chokes but should also be tested with a Utube water gage during the operation of the gin to

maintain correct doffing pressure.

The adverse effects of a defective doffing

mechanism are intensified by obstructions in gin

and lint flues, such as rust, and by joints and rivets

that accumulate cotton and affect the flow action

of fiber and air. Therefore these flues, as well as

condenser di-ums, should be kept clean and smooth

to prevent bacldash, which lowers the quality of

the cotton.

Dividing boards in brush gins need close

inspection to guard them against change in

position or wear. This board divides the saws and

brushes, and it is important that its proportions

be maintained. Some manufacturers provide

their patrons A\àth inexpensive metal covers for

this purpose. Worn dividing boards change the

volume and direction of the brush blast upon the

saws, which may seriously affect both the doffing

and the moting action. Tlie backboard or windboard, which is above the brush at the back of the

gin stand, must be kept free from wear and

sufficiently close to the brush tips so that fly and

lint do not accumulate in wads above the brush.

Picker rollers should be checked for missing

spikes and should be properly alined so that the

spikes center between saws.

Collections of hnt and fly may build up on fan

blades, thus destroying the balance of the wheel,

contributing to the vibration, and eventually becoming a menace to life and property. Fan wheels,

blades, and bearings should be carefully inspected

to reduce hazards incident to their use.

Seed elevators and conveyors of tlie screw or

helical type reciuire periodic attention to insure

satisfactory operation.

Pi-css_rams should be properly packed at reasonable intervals and petroleum o'ils should be used

as the hydraulic fluid instead of water. Although
MODKHXIZIXG COTTON GINS 37

such oils involve a slight expense, tliev ijrevent

corrosion and protect tlie polished plunger surfaces

and the working parts of the pump.

Gland packing on the rams, or ])lungers, of

presses should be given sufficient attention to

avoid breakdown and leaks.

Fire and Safety Precautions

Fire is a continual threat to cotton gins. This

necessitates installation and periodic iusi)ecii(in

of fire-extinguishing apparatus.

Expenditures for the care of the l)uildings and

premises to avoid roof leaks, protect the machinery, and lessen fii-e hazards by frec[uently removing

all chnging lint and dust are a good investment.

The use of sigiit-feed oilers on plain bearings

and the exercise of care in filling oil reservoirs on

other types of bearings, in addition to eft'ecting a

saving in lubricants, will minimize the hazards of

fire caused by sm-plus oil that runs onto the fioor

and machines. Hot boxes cause gin fires and may

be avoided bj^ adeciuate lubrication of bearings.

In gins equipped mth a boiler for power or conditioning, steam-smothering pipes may be attached to the distributor and lint flue. Patented

extinguishers using carbon dioxide and other gases

are also available.

The wisdom of other precautions, such as preveuting smoldng or carrying of matches, and tlie

keeping of an adequate force of labor on hand to

meet fire emergencies are obvious. Cotton-house

fii'es are common, and the same protection should

be arranged for them as for the gin building.

Whenever there is any likelihood that a bale lias

fire inside (i. e., "fu-e-packed") it should be placed

at once on the open lot at a safe distance from all

buildings, wagons, and other cotton. Constant

vigilance is the best precaution against fires, and

clean premises will generally prevent spontaneous

combustion or careless setting of fires.

Safety precautions should include the education

of all cjuployees m sah'ty-íirst measures the installation of sturdy guards to protect e^plovees

from moving macliinery, and the postino- of con

spicuous signs prohibiting anyone from attemptin»-

to remove chokages on the underside of o-iu rib«

during o]K'ralioiis. Much loss of life and limb is

caused annually by saw cylinders catchin«- tlie

clothing or arms of ein])loyees while they are ^--etting unck'r an operating gin stand. '^

APPEARANCE OF GINNING

ESTABLISHMENTS

The buildings and grounds of a ino(k'rn ginning

estabhshment present a clean, businesslike appearance in contrast to the unkempt atmosphere of

obsolete gins. Trash and refuse are not allowed

to accumulate. Surplus macliinery is neatly

stored under shelter. Condenser vents are kep't

free from fibrous streamers of dirty lint. Paint is

applied to improve appearance "as well as for

preservation.

Muddy lots seldom are found at modern gins,

and customers may drive their loads on graveled

roadways beneath shelter sheds to await their

turns. Good drinking water and clean toilet

facilities add greatl}^ to the comfort of the customers.

For metal buddings in the South, zinc paints of

the American Zinc Institute formulas or alumiuum

paints with oil or asphaltum bases are probably

the most duraljle, if the surfaces have weathered

for a few months before painting.

For wooden surfaces, metallic oxide paints in

reds, browns, and greens appear to be very (hirable.

The same colors are generally available in composition shingles for such structures as shelter sheds

and storage l^uildings.

Planting trees and slirul)S about the gin lot adds

greatlv to its attractiveness.
APPENDIX

For general handbook data, largely supplied by the Cotton Ginning Research Laboratories of the United vStates

Department of Agricultiire, the reader is referred to the

Arkansas-^Missouri Cotton Ginners Association Handbook

by Tom J. Johnston, Mississippi Extension Cotton Ginning

Specialist.

The following illnstrations—figures 37 to 43—provide

additional data of some of the results of gimiing research

work by the United States Department of Agriculture.

Table 6 supplies data for the power required in ginning

units. A glossary of cotton ginning terms is given on page

4.5.

Separat-or Mechanically actuated

shutoff valve on suction

Pressure

plate ""

-i^Electncal control

way pilot valve

_ for compressed

air or oilFeed ■■ i^OOOO

controller

Dropper

Controlled

bulk flow of

seed cotton

FinvRE 37.—ÜSDA design of bulk seed-cotton feed-rate

controller. Seed cotton may be poured into storage

hopper without regulating flow until adequately filled,

when the suction is cut off by the special valve behind

the separator. This cutoff mechanism also again opens

in ample time to continue steady operation. Its closure

provides marginal capacity to prevent chokes. A seed

control at the base of the storage hopper supplies seed

cotton to the ginning system at predetermined rate to

suit the ginner and the rate is not influenced by the suction-pipe attendant. With 1955 prices, a feed-control

system of this type represents an investment of $1,500

to $2,000.

T.vBLK 6.—Allowable hor.sepovjer consumption in

cotton gins for various units and assemblies

Ginning units

Horsepower per

Horse- batter}' for—

power !

per unit

Gin stand, saws and picker

roller

Brush gins, add per stand. _

Air-blast gin, add for fan

Mote conveyor per stand

Hull conveyor per stand

Seed conveyor per stand

Feeder, large extractor-cleanerfeeder

Stacked units over feeder

Convej'or-distributor

Seed-blowing regular fan

Turbo-blower pressure

Feeder hot-air supply

Trash fan, feeders, and stands.

Separator, cotton suction

Suction fan for separator

Condenser

Tramper

Press pump, flat bale

Cleaners, conventional screen

per cylinder

Cleaner, impact Continental

Gin Co., 54-inch

Vacuum wheel, seed cotton

Vacuum wheel, cottonseed..

Big-bur machine per foot of

length

Jembo overhead units, per

cylinder

Tower or vertical drier:

Full length, push-pull

Full length, suction or blow

Stub length, push-pull

Stub length, suction or blow.

Conveyor-type drier with fans.

Lint cleaner, saw, airblast:

To drive each unit

Condenser snction

Air-blast nozzle doffing fan.

Trash suction fan

Lint cleaner, saw brush:

To drive each unit

.\ir-foil fan on condenser

Trash conveyor or belt

Lint cleaner, air-jet of ABC:

Booster jet fan

Suction condenser fan

3/90

18

6

18

9

9

6

12

6

7%

16

10

3

1

40

30

34

'25'

35

4/90

24

8

22

12

12

8

14

8

10

19

33

5/90

30

10

27

15

15

10

16

10

10

12'

22

10 12^ 15

15 I 20 25

39 50

41

12 16

20 24

20 24

12 15

7K 10

"H 10

3 4

15 20

20 25

20

28

28

18

i2;.<;

12>^

5

25

30

38
MODERNIZING COTTON GINS 39

Inlet

FinrRE 38.—Cross section of USDA design of cleaner and

new principle for stick remover, showiiiij special features

of the device. (Public patent apiJlied for.) The peculiar action and outstandinji effectiveness of this cleaner

from older extracting principles are sixfold: 1, The regulated flow of seed cotton descends vertically and contacts the extracting saws at each stage without spreaders

or interference; 2, the saws carry the locks within the

arcuate-restricted space between their teeth and the

bar grids, scrubbing the locks as they pa.ss the grids;

3, the centrifugal force of sniall-dianieter high-speed

cylinders and locks "slings off" all Ijurs, sticks, stems,

and motes, and much pin-and-pepper trash is likewise

whipped off by the bar-and-tooth action; 4, the doffing

mechanism uses no metallic stripped blades, but it obtains a more gentle action on the seed cotton with the

brush cylinders; 5, the reclaiming element of the machine prevents loss of good fiber; and 6, the vertical

trash chute moves the foreign matter without further

contact with the cleaned cotton.

feeding

1 control

nders

Kicker

"roller

7-inch

diameter

saws

ô-inch

diameter

brushes

Reclaimer

cylinders

Cotton

discharge
40 AGR. PrANDBOOK 99, U. S. DEPT. OF AGRICULTURE

Y4-inch_ plate

with

„ Adapter

Z4 connects to

drier outlet

30'^

If dropper is not

needed use Ho. 16

gage airtight slide

..- < ° ;

FiGUKE 39.—USDA design of green-boll and rock trap, showing construction. This unit enables the modern cotton gin to

eliminate very troublesome unopened green bolls before they are smashed into masses of sticky vegetable pulp that

produce chokes and much trouble. Tramp iron, rocks, bottle caps, and other injurious elements are also taken out

by the trap. The details show no magnet. For its use, please refer to figure 8.
MODERNIZING COTTON GINS 41

FIGURE 40.—USDA nondrip design of moisture restoration to overdried cotton filxT on tlie gin lint slide. This

system restores approximately 4 poiind.s of moisture per

bale (less than 1 percent of the bale weight) to offset

partially the producers' loss of 3 percent by drying.

Only approved chemical solutions of nonstaining, hygroscopic wetting agents are to be used. Each nozzle shall

be a guaranteed calibrated unit of not to exceed 2.2

gallons' capacity per hour at 40 pounds' gage pressure.

Two nozzles are ample for 3 or 4 stands, and 3 nozzles

will fully serve a 5-stand, 90-saw outfit. In operation,

when the manual switch is closed and cotton lint raises

the swing flap (not shown) to which the mercure' switch

is attached, valve No. 1 opens while valves Nos. 2 and

3 close simultaneously. "\Mienever the flow of lint cotton ceases from the condenser, valve No. I closes and

valves Nos. 2 and 3 open to drain the nozzles.

Wiring diagram
42 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

Trash fan Side

Elevation

Pink Bollworm Quarantine Regulationsjar Single Fans Handling

Gin Trash

Minimum Fan Mini- Highest

inlet wheel safe

diamelcT

(inches) diameter low

speed speed

1 Inches J!. p. m. R. p. m.

Í 19

1 20

2, 700 3, 020

10 2, 020 2, 800

20;,^ 2, 500 2, 790

21 2, 490 2, 730

10/2 to 11 _

22 2, 380 2, 610

23 2, 280 2, 490

23 !< 2, 230 2, 440

24 2, 180 2, 390

11}^ to 12. { 25 2, 090 2, 290

26 2, 060 2, 200

I 26H 2, 020 2, 160

Í 27 1, 980 2, 120

28 1, 910 2, 050

29 1,840 1, 980

30 1, 790 1, 910

12H 31 1, 725 1, 850

32 1, 700 1, 790

32H 1, 700 1, 760

I 33 1, 700 1, 760

Code design for

taper in lei to fan

FIGURE 41 —Pink bollworm quarantine handling of cotton gin trash; single-fan system and details. Gin trash infested

with pink bollworm must be treated in some manner to kill the worms before removal from the gin lot. This

figiire illustrates fan speeds, fan connections, and a collection system that has been approved by the Plant Pest

Control Branch, Agricultural Research Service, for treating gin trash for local release as stock feed and for soil improvement. For complete information on pink bollworm quarantine, please consult the Plant Pest Control Branch,

ARS, United States Department of Agriculture, Washington 25, D. C.
MODERNIZING COTTON GINS 43

FIGURE 42.—Cotton-gin trash incinerator. This design

has a square cross section with square base and masonry

walls, upon which any sort of dome structure may be

erected. The normal capacity of this unit is approximatel}^ 5,000 pounds of trash per hour. The superstructure here shown will receive some cooling by means

of a 3-inch air-inlet slot extending around the edge of the

bonding. The trash cyclone should be of a size to suit

the number of trash pipes and to provide for dust elimination. A tall, large-diameter guide stack will remove

objectionable smoke from the vicinity.

Shack 5o"x5û'or more
44 AGR. HANDBOOK 9 9, U. S. DEPT. OF AGRICULTURE

liV».

/ From '

gin stands jP' f

FIGURE 43.—Master type of lint cleaner for serving a complete batterj' of four or more gin stands. When

lint cleaner is in use, the bj'pass valve is closed so that freshly ginned lint from the main lint flue is

diverted to ilie lint cleaner. A double-section, large-capacity lint cleaner is shown here. For small

gins with three gin stands or less, a single rather than dual cylinder unit is used.
MODERNIZING COTTON GINS 45

GLOSSARY OF COTTON GINNING TERMS

AIR-BLAST GIN:

AIR-DRAFT CLEANER:

AIRLINE CLEANER:

AIR VALVE:

BREAST (OR FRONT):

BRUSH GIN:

BOOT:

BYPASS:

CLEANER:

CLEANING FEEDER:

CONDENSER:

DoFFER ROLLS:

DOFFING:

DISTRIBUTOR:

EXTRACTOR:

EXTRACTOR, UNIT:

One that doffs the ginned lint

from the saws by a bhist of

air.

Air line cleaner made by Lummns Co.

One in which the cotton is conveyed while in the gin suction

piping; i. c., in the "air line."

The automatic or manual suction-V)reaker to stop flow of

air at the cotton telescope, or

to switch flows of air.

Front of a gin stand.

One that doffs the ginned lint

from the saws l)y a brush.

The flexible canvas at the upper

end or bell of the telescope.

May also he made of metal.

A passage around a machine to

avoid use of the machine.

A machine for removing dirt

and small trash from seed

cotton. Does not do "extracting."

A cleaner and feeder combined.

A machine to collect ginned lint

into a smooth, endless "l)at."

Rolls that doff, or strip, the

ginned lint from the condenser drum.

The act or process of removing

cotton lint from any part of

a machine.

A device to distrilnite seed cotton to various machines or

cotton gins. Excess cotton

from this device is discharged

at the overflow. A distributor

may be of the belt type or

pneumatic or equipped with

auger or helical screw.

A device for extracting burs,

stems, whole leaf, and other

trash from seed cotton. May

do some cleaning also, but

should not be confused with

a cleaner.

A small extractor suitable for

use in replacing a cleaning

FEICDEH:

FEEDER APUON:

FLOAT HOARD:

TIULLER RIBS:

]I ULLER BREAST:

I, S. & B.:

T>A.MB REQUIN:

I>INT FLUE:

¡MOTE BOARD:

¡\IOTING:

PICKER:

PICKER ROLL:

PRESS:

PNEUMATIC ELEVATOR:

RAM:

ROLL BOX:

SEPARATOR;

SEED-ROLL:

SEED-BOARD:

TELESCOPE:

TIíAMPER:

feeder over a gin stand.

(Usually müde in gin stand

widths.)

Set- CLEANI.VG FEEDER.

The aproiilike discharge pan

from feeder into gin stand.

The flap at back of roll box in

an automatic roll-density control on a cotton gin.

The front set of ribs in a

double-ril) gin.

The front to which the huiler

ribs are attached.

Abbreviation for "Independent

saw and Ijrush drive."

The lever of the seed l)oard.

Flue or pipe to carrv off ginned

lint.

A partition, usually movable, to

deflect motes.

The casting out of motes. May

be done by gravity or by

centrifugal force.

An extractor. A harvester on

the farm.

A special beating or extracting

roller in the front, or breast,

of a cotton gin.

Bale press. May be either

"low" or "standard density"

type.

The upper part of a pneumatic

gin. Now seldom used in the

United States.

The hydraulic lifting and compressing element of a press.

Seed-roll box, a compartment

holding the seed cotton in

contact with the gin saws.

A machine to separate seed

cotton from the air currents

of the suction fan.

Roll of seed cotton in the roll

box.

Adjustable, fingered plate at

bottom of roll box.

Wagon suction pipe, telescopic,

for readv unloading.

Part of tiie press mechanism.

Known also as a packer.

U. S. GOVERN 1ENT PRINTINO OFFICE: 1956

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For .sale by the ^-^"^^^^¡l;Xr:í^u:c:"^Vn'^-^^ ^' "^^