Improvements in the Manufacture of Drawn Shafting and Tubing, and in Apparatus for that purpose.
Year: 1896

page_text: Date of Application, 14th Nov., 1895
Complete Specification Left, 13th Sept., 1897-Accepted, 23rd Oct., 1897
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Drawn Shafting and Tubing,
and in Apparatus for that purpose.
I, OLIVER IMRAY, of No. 28 Southampton Buildings, Chancery Lane, in the
County of London, Chartered Patent Agent, do hereby declare the nature of this
invention (as communicated to me from abroad by William A. McCool of
No. 1008 Eight Avenue, Beaver Falls, County of Beaver, State of Pennsylvania,
United States of America, Manufacturer,) to be as follows:-
This invention relates to the manufacture of solid rods constituting drawn
shafting or of hollow rods constituting drawn tubing, the latter being drawn either
from bored blanks or from butt or lap welded blanks.
In order to remove scale or oxide at any stage of the drawing process, chiefly
after heating or annealing the blank, instead of employing acids or other chemical
substances which have deleterious effects on the metal, the surfaces are, according
to this invention, cleared of scale by mechanical abrasion by hardened metallic
globules or particles driven against the surfaces by a blast of air in the manner
of the sand blast, but without the use of saud or like material which by adhering
to the blank might damage the tools employed for drawing it. This abrading
process also by making numerous small indentations or pits allows the metal,
while subjected to the drawing action, to flow more freely.
In order to loosen scale inside a tube blank, the blank is preferably drawn in
the first instance through a die so as to compress the metal and crack the interior
scale.
When butt or lap welded tubes are to be drawn, they usually have an internal
prominence or rib in the line of the weld.
This at an early stage of the process is removed by drawing through the blank
a suitable cutter held in a head formed with a cavity for receiving the cuttings
and an outlet for them behind the cutting head.
The drawing machine comprises a bed about the middle of which is fixed a
block containing the die, and at the front end a bracket for holding the end of a
mandril when tubes are drawn. On the bed, on each side of the die block is
a sliding carriage provided with a screw clamp to hold the shaft or tube, and a
gripper to take hold of the pull which is a cable, preferably of steel of uniform
section throughout, so that the gripper can take hold of it at any part of its length.
The gripper consists of a pair of bars each hollowed to partly embrace the cable
and each carried on a pair of radius arms adjusted to an oblique position so that
they tighten the gripper the more forcibly they are drawn towards an attitude
at right angles to the cable. In order to allow certain yield in case of undue
obstruction the cable is driven by frictional contact with its driving pulley
allowing slip in case of extreme pull.

page_text: When tubes are drawn, a mandril is fixed by its end in such a position that its
head is within the die. This head may be of round form fixed to the stem, or it
may be a ball seating in a hollow at the end of the stem and free to turn in the
hollow. In order to steady the mandrel, radial arms having their ends hollowed
to embrace it, project from vertical rock spindles mounted at each side of the bed,
these spindles being urged by springs to turn so as to press the arms against the
stem of the mandrel. On the rock spindles are other arms which come in the
way of the carriage so that as the carriage advances and presses on these arms
moving them aside the spindles are caused to turn moving the radial arms out of
the way of the carriage.
The stem of the mandril may be made tubular and charged with lubricant
which can be forced through holes at the head.
For drawing a shaft or tube the blank is clamped in one of the carriages with
part of its length projecting beyond the carriage, and the cable being held by the
gripper is drawn onwards forcing the shaft through the die, or forcing the tube
through the die or over the mandrel or between the die and mandrel. When
the front part of the blank presents itself beyond the die, it is clamped in the
second carriage, and it being gripped to the cable is in its turn advanced drawing
the blank onwards.
Dated this 14th day of November 1896.
ABEL & IMRAY,
Agents for the Applicant.
Improvements in the Manufacture of Drawn Shafting and Tubing,
and in Apparatus for that purpose.
2
I, OLIVER IMRAY, of No. 28 Southampton Buildings, Chancery Lane, in the
County of London, Chartered Patent Agent, do hereby declare the nature of this
invention (as communicated to me from abroad by William A. McCool of
No. 1008 Eighth Avenue, Beaver Falls, County of Beaver, State of Pennsylvania,
United States of America, Manufacturer) and in what manner the same is to be a
performed to be particularly described and ascertained in and by the following
statement:-
This invention relates to an improved method of and apparatus for drawing
cold metal and treating it at different stages. No chemicals are used for "cleaning"
or removing "scale"; improved apparatus are employed for drawing; and the a
method and apparatus are such that fine tubing can be manufactured either from
lan-welded or butt-welded tube blanks or from specially prepared blanks.
To clean or remove "scale" at any stage, no chemical treatment, but mechanical
abrasion is employed. For this purpose a blast of air is employed charged with
minute metallic globules, like chilled steel shot, these not being liable to adhere to
the surface of the metal or cut or damage the dies. This abrasion can be applied
as often as desired, being generally necessary at commencing and after each
annealing. In order to loosen scale inside a tube blank it is drawn through a
die so as to compress the metal and crack the interior scale.
The accompanying drawings illustrate tools and machines for carrying out this
invention.
Figure 1 is a side elevation, partly in section, of the drawbench. Figure 2 is
an end elevation. Figure 2 shows the mandrel holder. Figure 3 is a plan.

page_text: Figure 4 is a section of a mandrel. Figure 5 is a partial plan of the bench with
a modified mandrel. Figure 6 shows the die mandrel of Figure 5 and die in
section. Figures 7 and 8 are respectively an elevation and a section of the die
holder. Figures 9 and 10 show the adjustable die holder supports. Figures 11
and 12 are sections of the die and holder. Figure 13 is an elevation of one of the
carriages. Figure 14 is a sectional plan of the carriage. Figure 15 shows the
guide used with the mandrel in Figures 5 and 6. Figure 16 is a section on
line of Figure 5. Figure 17 is a section looking in the opposite direction.
Figure 18 is a front elevation of the abrading apparatus. Figure 19 is an end
elevation; and Figures 20, 21, 22, 23 and 24 are detail views of parts thereof.
Figure 25 illustrates the manner of cleansing the interior of a tube. Figure 26
is a section of tube and a broaching tool for trimming it. Figures 27 and 28 are
sections on the line - and y-y, of Figure 26 respectively.
1, 1, indicates the side pieces of the draw bench supported by pillars, 2. The
drawbench has an extension comprising two parallel bars, 3, 3, and cross-pieces, 5,
and supported near its outer end by uprights, 4. On the frame is a die holder, 6,
with a ball-like head, 7, at one end, and at the other end a somewhat similar
head, 8, with a stud, 9. The ball end, 7, of the die holder, as shewn in Figure 10,
is in a socket piece, 18, mounted adjustably in support, 19, bolted to one of the
side pieces 1, and the stud, 9, of the die holder, as shewn in Figure 9 is held in an
arm 21, which lies between screws, 22, on a plate 23, fastened to the other side
bar, 1. By moving the screws, 20, 22, the die holder can be both adjusted
lengthwise on the bench or rocked about an axis transverse to it. The holder, 6,
as shewn in Figure 12, has a cavity, 10, an aperture, 11, and a flange, 12, forming
an abutment for die, 14 (Figure 11). The die has two mouths, 15, 16. Cavity 10
and die 14 are cylindrical in cross-section, and the holder has slots, 13, opening
into socket, 10. By bolts, 17, the walls of cavity, 10 are drawn together and
firmly grasp the die. There are guides, 25, on the bench, formed by angle bars, 24,
and in them run wheels, 28, of carriages, 26, 27, the wheels being on axles, 29.
Each carriage has jaws, 30, for engaging a tube or rod and jaws 31, for engaging
the traction rope 40, which passes over guiding drums 42, and a driving drum 41,
driven by worm wheel 43, from worin 44 on shaft 45 which has two loose
wheels, 46, 47, alternately clutched to the shaft by levers 48, 49, working friction
clutches within the wheels; as these wheels move oppositely, the levers control the
movement of the rope 40.
Each carriage, 26, 27, has toggle links, 35, between the jaws 31 and the frame
walls. 32 (Figure 16) is a shaft having fingers, 36 which engage with the jaws 31.
On the end, 37, of the shaft 32, a handle is applied by which the operator can
move the jaws at any instant, and the links, 35, hold the cable with great force,
against the drag of the rope. The toggle links 35, bear against bars, 33, bearing
against inclines 34 which can be adjusted by screws 39.
The upper jaws, 30, for gripping the tube or rod, are moved by shaft, 38.
By employing a cable instead of a chain, the drawing is effected entirely by
friction. The engagement between the drum and the cable, 40, is frictional, and,
also, that between shaft 45, and the wheels, 46, 47, so that there can be a yielding
in case of severe strain. Moreover, a wire cable, owing to its elasticity, permits
certain yielding, and the machine acts much better than those having positive
drawing devices.
As the cable is, throughout, of uniform cross-section, engagement or disengage-
ment can be readily attained at any part of it. In using the parts as in Figures 1, 2
and 3 and 4 the tube is first placed on the mandrel, 50, and then drawn through
the die. The body part 51 of the mandrel is tubular and has a stem 53 screwed
at 54, and having a collar, 55, holding 52, in position. 56 is an oil passage
communicating with the body 50, and with the lateral passages 57.
A lubricant material in the body, 50, is forced by a plunger, 63 through the
passages, 56, 57, 59 is the plunger rod which is screwed in the end piece, 58,
and turned by a wrench applied at 60. 64 is a washer which is, held by a

page_text: collar, 54, and prevents the lubricant from moving backward from the mandrel
head, 52.
66 is an adjustable crosshead or abutment held on the frame 3 and engaging
grooves 65 on the mandrel. It is held by guides 70, on the end plate, 73, having a
thrust block, 74 and an adjusting screw, 72. 71 is a wedge movable by the 5
screw 72 and engaging with thrust block 74, and cross-head 66, to adjust the
mandrel longitudinally. The mandrel is detachably locked by bar 67, pivoted
at 68, and having locking handle, 69.
In operating, the mandrel 50 is removed, a tube blank 75 is placed on it, the
mandrel is properly adjusted and locked; then the jaws, 30, of the first
carriage, 26, are clamped to the tube, and the jaws, 31, to the rope 40. The
carriage then pushes the tube through the die and over the mandrel head, 52.
When the tube end reaches the second carriage, 27, the first one, 26 is disengaged
from both tube and cable, and these are connected to the grippers in the carriage 27,
which pulls the tube through the die.
Sometimes it is preferable to arrange the mandrel as in Figure 5. Here the
mandrel, 76, is in a block, 77, at the end of the bench, and held at intermediate
points by arms 81, each on a rocking shaft, 82 (Figure 17) journalled in
bearings 83, 84, and having a spring 85, to press the arm 81 against the mandrel
86 is a finger on each shaft 82 in the path of the carriage, 87 are detachable
wearing blocks. When the carriage 27, moves against the finger 86, the bar 28"
swings the arm 81 away from the mandrel, and after the carriage has passed,
the arm is, again by the spring forced to engage with the tube. 79 is a holder for
the ingoing tube, it has two guide rockers, 80. This mandrel, 76, in Figure 5,
has a loose spherical head, 78, and a socket adapted to receive it. The arms, 81,
may be held out of position by stop, 86, when the machine is used as indicated
in Figures 1 and 3.
Solid rods or bars can be drawn through the machine, the mandrel, in such
case, being omitted.
Die 14 is reversible, and if one mouth becomes worn, the die can be readily
turned and the other brought into use; thus saving much of the labour and expense
incident to changing and dressing dies.
In Figures 18 to 25 mechanisms are shewn for cleaning the metal, at times
between the stages of drawing or before commencing. 90 is a drum holding a
number of tubes, 132, or bars, 131. It has strengthening bands 91 resting on
rollers 92 on shaft 93. It may also have rings 94 resting on rollers 95. 96 are
air reservoirs connected by ducts 98, with a compressor 97, and by flexible ducts 96",
with receptacles, 99, 100, having discharge pipes, 101, 102, which extend through
the heads of the drum, 90, and are connected together near the nozzles, 103, 104,
by a coupler, 105. The receptacles 99, 100, are moved by rod, 106, and a
travelling belt or cable, 107, on wheels, 108, connected at 109 to the bar, 106.
110 is a power shaft driving the shaft 93 by shaft 93, belting and wheels, 111,
112, 113 so as to rotate the drum 90, through the rollers 92, 95. 114 are
receptacles for the abrading material, each communicating with one of the
moveable tanks by the flexible tube, 115. 116 is a pipe communicating with the
receptacles 114, and 117 is a fan driven from shaft 93 by belt, 118.
In operation the tubes or bars are placed in the drum, 90, through doors, 126.
and the mechanism is put in action. As the receptacles, 99, 100, move toward
and from the drum, 90, the nozzles 103, 104 traverse the drum longitudinally and
deliver the air blast and the abrading particles under great force to the surface
of the metal articles. As the drum rotates, it brings new articles to the top and,
also, causes them to turn upon each other, and so new surfaces are being constantly
presented for abrasion. The tubes or rods are separated by collars, 133, to expose
all their surfaces. The drum has escape apertures, 125 through which the
abrading material passes to hoppers, 119, through ducts 120 into tanks 121 which
receive material from the drum and deliver it to the receptacles, 114, through
tubes, 123,

page_text: 122 are pipes connecting the receptacles 121 with the tops of the hoppers 119.
The fan, 117, causes a suction upwards through the tubes 123 and receptacles 114,
and thus the abrading material is carried from the tanks 121, up to the recep-
tacles 114. 127 is a deflector in the top of each receptacle, 114, to prevent the
particles passing to duct 116. Each of the tanks 99, 100, is divided into two
chambers by a wall 129, having an aperture 130, into the nozzle, 128, which
connects with the air blast supply pipe.
After the articles have been cleaned, the drum is stopped and they are removed
and others are inserted.
In Figure 25 is shown a tube, 131, with a nozzle, 135, on a hose, 134 inserted,
for removing scale from the interior.
A butt-welded or lap-welded tube has a thicker line, 142, along the weld. This
surplus metal is removed by the tool in Figures 26, 27 and 28, which has a
body 136, a stem, 137, and a pull rod, 138. The ends of the part, 136, are
cylindrical, but between them is a chamber, 140, with a passage 141 for cuttings
extending backwards. 139 is a cutter having its cutting edge in the arc of the
surface behind it. 143 is a groove which receives the thick rib, 142, and serves
to guide the cutter and to prevent its rotation.
By employing this process and machinery acids or chemical agents are avoided
in the cold-drawing of tubes or other articles. When chemical agents are employed
they attack the pure metal, make the drawing difficult and leave pits and impure
surfaces which interfere with enamelling, japanning, or plating. Mechanical
abrasion on the other hand removes the foreign material, and exposes the fibres
so that after drawing, a hard, smooth, polished pure surface is presented. More-
over, the interior of common butt-welded or lap-welded tubing can thus be cleaned
and finedrawn tubing can be manufactured therefrom, which has been impossible
with earlier processes, depending on acids or chemical reagents. Internal scale
of a tube may be removed by drawing the tube a little smaller without a mandrel,
the scale being cracked by the compression. Although I prefer to employ this
and the mechanical abrasion above described for removing scale, there may be
cases when dilute acid is necessary, as may be readily understood.
By employing a yielding device for drawing like a cable with a friction gripper,
the fibres are not torn or broken.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I claim in
respect of process and apparatus for drawing tubes or rods is:-
1. The herein described method of cleansing the surfaces from scale and oxide
by mechanical abrasion effected by directing against them a blast of air carrying
hard particles.
2. The cleansing apparatus comprising a revolving drum means for delivering
air blast with hard particles from nozzles moving longitudinally therein, vessels
and pipes for collecting and delivering the hard particles, compressor and fan,
substantially as described.
3. In a tube or rod drawing machine the combination of a bed, a stationary
die, and a mandrel, a pair of carriages with grippers for the tube or rod and
grippers for the pull-rope, substantially as described.
4. The lateral supports for the mandrel each comprising a pair of hollow ended
arms fixed on spring urged vertical spindles, provided with fingers in the path of
the carriage, substantially as described.
5. The drawing carriage having adjustable tube clamps and grippers for the pull,
actuated by toggles bearing against bars adjustable on inclines, substantially as
described.
6. In combination with a cup ended mandrel a ball seating therein, substantially
as described.
7. A cutter tool for removing internal projecting ribs of the tube blanks
substantially as described.

page_text: 8. For propelling the drawing carriages a wire rope of uniform section so that
it can be gripped anywhere, and driven and driving by friction so as to be capable
of yielding to extreme stress, substantially as described.
100%
ABEL & IMRAY,
Agents for the Applicant.