Engineering
manualFullsan Flat

Siegling – total belting solutions

Siegling Fullsan compliments the Forbo Movement Systems
conveyor belt range with homogeneous belts made from highgrade polyurethane. Our extensive experience in light materials
handling is your guarantee not only of outstanding productquality, but also of competent advice, rapid availability and practice-oriented service.

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Siegling Fullsan Engineering Manual · 02/2023

Better hygiene withSiegling Fullsan
Siegling Fullsan is virtually resistant to contamination of oil, grease, moisture and bacteria. Siegling Fullsan is very easy to clean, and is exceptionally well suited to use inespecially hygiene-critical applications (dairy products, dough processing, meat andpoultry processing, as well as other food processing applications).

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Siegling Fullsan Engineering Manual · 02/2023

Index1 Basics. . . . . . . . . . . . . . . . . . . . . . . . . . . . .  6

2 Conveyor design . . . . . . . . . . . . . . . . .  16

1.1	Technical data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Fullsan Flat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
	Type key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.1	General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Conveyor components . . . . . . . . . . . . . . . . . . . . . . . . 18
	Hygienic design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
	Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

1.2 Belt fabrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
	Splice types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Belt features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.3 Belt selection and sizing . . . . . . . . . . . . . . . . . . . . . . . 12
	Drive types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Pre-tension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Calculating the required belt length . . . . . . . . . . . 13
1.4 Factors influencing belt life . . . . . . . . . . . . . . . . . . . . 14
1.5 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.2	Notes on conveyor construction . . . . . . . . . . . . . . . 22
Frame and support . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Belt side guides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Conveyor speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Conveyor length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
	Expansion/contraction due to temperature . . . . 24
	Take-ups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Quick release tensioning devices . . . . . . . . . . . . . . 25
	Scrapers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
	Side limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Feeding in the transported material . . . . . . . . . . . 28
2.3 Belt support on the carrying side . . . . . . . . . . . . . . 30
	General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Flat (table) supports . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Parallel wearstrips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
V-shaped arrangement of wearstrips . . . . . . . . . . . 34
	Supporting the belt with rollers . . . . . . . . . . . . . . . 36
2.4 Belt support on the return side . . . . . . . . . . . . . . . . 37
	General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
	Supporting the belt with rollers . . . . . . . . . . . . . . . 38
	Sliding belt supports . . . . . . . . . . . . . . . . . . . . . . . . . . 38
2.5 Fullsan Flat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
	Drive | Pulleys | Tracking
	General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
	Drive types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
	Drive and idler shafts . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Belt tracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
	Absorbing lateral forces withlongitudinal profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

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3 	Conveyor layouts . . . . . . . . . . . . . . . . 50
3.1 	Horizontal conveyors . . . . . . . . . . . . . . . . . . . . . . . . . . 52
	General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Conveyor layouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
3.2 	Incline/decline conveyors . . . . . . . . . . . . . . . . . . . . . 53
	General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
	Incline conveyor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
	Decline conveyor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
3.3	Hockey-stick and swan-neck conveyors . . . . . . . . 54
	General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
	Use of profiles (flights, sidewalls) andbending/counter-bending radii . . . . . . . . . . . . . . . . 55
	Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Belt guidance in the concave curve(top side of belt) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Belt guidance in the convex curve(underside of belt) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
3.4 	Troughed conveyors . . . . . . . . . . . . . . . . . . . . . . . . . . 58
	General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
	Transitional area between
end pulley and trough . . . . . . . . . . . . . . . . . . . . . . . . 58
	Trough angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
	Siegling Fullsan series and trough shape . . . . . . . 59

	Legal notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

5Siegling Fullsan Engineering Manual · 02/2023

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1 Basics

1.1 Technical data
1.2 Belt fabrication
1.3 Belt selection and sizing
1.4 Factors influencing belt life
1.5 Cleaning

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1.1	Technical Data

Total thickness
approx. [mm (in)]± 0.15 (0.006)

Effective pull at 1%
elongation (k1 % relaxed)[N/mm width]

Min pulley ø without
counter bending [mm (in)]Min pulley ø withcounter bending [mm (in)]Permissible operating
temperature [°C]

Permissible operating
temperature [°F]6400196400206400216400226400236400246400253 (0.12)3 (0.12)3 (0.12)3 (0.12)3 (0.12)3 (0.12)3 (0.12)

9.0
9.0
9.0
9.0
9.0
9.0
9.0

40 (1.57)
40 (1.57)
40 (1.57)
40 (1.57)
40 (1.57)
40 (1.57)
40 (1.57)

40 (1.57)
40 (1.57)
40 (1.57)
40 (1.57)
40 (1.57)
40 (1.57)
40 (1.57)– 10/+70– 10/+70– 10/+70– 10/+70– 10/+70– 10/+70– 10/+70

14/15814/15814/15814/15814/15814/15814/158Belt types

Article number

Fullsan Flat

FLT+ U30 GL/GL-NA HACCP BL FDA
FLT+ U30 GL/MT-NA-HACCP BL FDA
FLT+ U30 GL/NP-NA HACCP BL FDA
FLT+ U30 MT/GL-NA-HACCP BL FDA
FLT+ U30 MT/NP-NA-HACCP BL FDA
FLT+ U30 NP/GL-NA HACCP BL FDA
FLT+ U30 NP/MT-NA-HACCP BL FDA

Blue (RAL 5015)

8Siegling Fullsan Engineering Manual · 02/2023

Type key (all Siegling Fullsan series)
FLT	= Flat top+	=	Reinforced (Pro) version

Type designation for Siegling Fullsan belts

FLT
FLT

		 U 30 MT / GL - NA - HACCP BL+ 		 U 30 NP / GL - NA - HACCP BL
Belt
property

FDA
FDA

Color

Belt
property

Belt property
Surface finish top face
Surface finish underside
Belt thickness (FLT) / Deck height (CD/PD) in 1/10 mm
Belt material
Reinforced
Pitch
Fullsan series

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U	= PolyurethaneGL	=	SmoothMT	=	MatteNP	=	Inverted pyramidNA	=	Non-antistatic
HACCP	= Supports the HACCP concept
FDA	=	Food safe in compliance with EC/FDA
BL= Blue1.2 Belt FABRICATION
Splice types
When choosing the type of endless splicing, take into account:– Hygienic aspects– Material being conveyed– Tensile forces in the belt
– Conveyor design/application environment (can endless splicing be carried out on the conveyor?)– Cleaning method · Cleaning-in-place (CIP), Cleaning-off-place (COP)All belts are also available as open roll material or with prepared ends.

Splice type possible with
Fullsan Flat

10

Butt splice(standard)●

Hinged lace
(only for 3 mm
belt thickness)●

Hook fastener●

Plastic rivet●

Clamp fastener(metal)●Siegling Fullsan Engineering Manual · 02/2023

Belt features
Perforations
Belt perforations available for all belt types. Available in various holediameters and patterns. Contact customer service for examples of row
perforations and additional information.

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1.3 Belt selection and sizing
Drive types
Drive type possible with
Fullsan Flat

12

Head drive

●

Lower
head drive●

Center drive(e.g. Omega drive)●

Tail drive●

Siegling Fullsan Engineering Manual · 02/2023

Pre-tension
Depending on the type and application, Siegling Fullsan
belts work with different pre-tensions.
Even with low pre-tension, which could be generated by
the belt sagging on the return side, it is often advantageous
to use a take-up or quick tensioning release take-up (seesection 2.2). This makes the belt easy to fit, and provides
good control over the belt sag. In addition, it enables fastand convenient cleaning of the belt and conveyor.

A
A x 0.3

1

The tensioning range (A) should be calculated so that withthe take-up extended 30 %, no pre-tension is generated,
and at least the desired pre-tension can be achieved withthe remainder of the travel (fig. 1).

Calculating the required belt length
The required belt length can be determined using thefollowing calculation process (fig. 2):a– Find the total of the individual span lengths in thestretched state. Assume that position-dependent
take-ups are extended 30 % (a).

a
b
a
b
c
b
c

– Find the total of the individual arc lengths at all
deflection points (b).
– Find the additional required belt length resulting fromthe desired catenary sag (c) (see section 2.4).

c– 	Add these values.
– Correct the result if necessary taking expected load states
into account (belt length and width change dependingon the loading).

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2

1.4 Factors influencing belt life

The following diagram shows the basic effects of various influencing factors on the service life of a Siegling Fullsan belt.

normal lifetime of the belt

Increase throughlarge pulley diameters
few diversions
moderate loading
moderate belt speed
narrow glide bars
appropriate cleaning
few start/stop operations
moderate operating temperatures

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1.5 	 Cleaning

To achieve optimum cleaning results, coordinate the cleaning process in detail with your cleaning agent supplier andyour contact at Forbo Movement Systems.

Notes:

Follow the steps below to clean:– 	Maintain a safe distance between belt and water nozzle.

1 Make sure all large particles and residues are removed
using scrapers or brushes.

– 	Water temperature should not exceed 65 °C (150 °F), toavoid proteins sticking to the belt surface, as well as forsafety reasons.

2 Rinse with hot water (55 – 60 °C / 130 – 140 °F).
Do not use boiling water or extremely high pressure as
this will reduce belt life.
3 Apply an alkaline cleaning agent to the belt surfaces thathas been approved by your plant sanitarian, sanitary
operation procedures, or cleaning chemical supplier.
4 Rinse the belt with hot water (55 – 60 °C / 130 – 140 °F).
Do not use boiling water or extremely high pressure as
this will reduce belt life.
5 Disinfect with a disinfectant that has been approved byyour plant sanitarian, sanitary operation
procedures, or cleaning chemical supplier.
6 Rinse the belt with hot water (55 – 60 °C / 130 – 140 °F).
Do not use boiling water or extremely high pressure as
this will reduce belt life.

15

Siegling Fullsan Engineering Manual · 02/2023–	Water pressure should not exceed 17 bar (250 psi), toavoid aerosol contamination.

– 	Do not exceed the specified concentration or temperature for the cleaning agent. Please refer to your plantsanitarian, sanitary operation procedures, or cleaningchemical supplier for proper use of and recommended
chemicals for your specific needs.
Our TecInfo 09 also offers you a detailed description.
Please inquire.

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2 Conveyor design

2.1 General
2.2 Notes on conveyor construction
2.3 Belt support on the carrying side
2.4 Belt support on the return side
2.5 Fullsan Flat
Drive | Pulleys | Tracking

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2.1	General
Conveyor components
Conveyors may differ considerably fromthe diagram shown here due to different
drive types and layouts.

Carr yingside“Tail”“Head”

1

1

Return s
ide

2

2

3

Fullsan Flat

All Siegling Fullsan Series

2

9

8

4
5
7

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6

➊ Siegling Fullsan homogeneous belts
Conveyor carrying side➋	Guide rails to guide the belt at the sides➌ 	Different types of belt supports
Conveyor return side
➍	Return rollers (if necessary with flanged pulleys to guide the sides of the belt)➎ Belt sag“Tail” of the conveyor (infeed)➒	Idler shaft/drum (at the “tail” of the conveyor, optionally designed as a take-up)

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Siegling Fullsan Engineering Manual · 02/2023

All Siegling Fullsan Series“Head” of the conveyor (outfeed)➏	Drive shaft/drum (at the “head” of the conveyor)➐	Scraper➑	Snub roller

2.1	General
Hygienic design
Siegling Fullsan belts are very often used in applications where high hygiene standards have to be maintained. The system as a whole can only meet thesestandards in conjunction with an adequate conveyor
design.

–	If bolted connections are unavoidable, do not leave any
thread sections exposed; do not use star washers as
clamping elements and do not use Allen screws. All joint
areas should be easy to clean.

Where high hygiene standards are required, conveyor
systems and conveyors have to be constructed according todesign principles that avoid relevant design weaknesses.
Dirt must not build up; materials, surfaces and components
should be easy to clean.

–	Never drill into completely sealed tube sections, not evento create internal threads, e.g. for adjustable feet.

All Siegling Fullsan Series

Therefore, in these cases, bear the following principles inmind:– Keep the overall design as simple as possible to avoid
dirt traps.

–	Never design inner radii that are smaller than 3 mm.

–	Design for easy tool-free installation and removal ofaccessory parts, e.g. belt guides.
– Finish all surfaces that are in direct contact with food in
accordance with relevant food hygiene regulations (grind,
polish, passivate, …)–	Use only materials that are easy to clean and resistant tofrequent cleaning, and are food safe where applicable.
Note the materials table on the next page.

–	Use as many supports as structurally necessary.
–	Avoid using mechanical belt splices whenever possible.
–	Avoid using tubes that are not completely sealed. Instead
use solid bars wherever possible.
–	L and U sections as well as surfaces should be positioned
so that liquids reliably run off them.
– For the joining technology, give preference to clean
welded joints (welded seams in contact with food should
be ground/cut flat).

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Siegling Fullsan Engineering Manual · 02/2023

Detailed information about hygienic design requirements
and hygienic operation can be found in the publications of
the European Hygienic Engineering & Design Group(EHEDG) | www.ehedg.org
In addition to the requirements listed here, the further sections on conveyor design should also be taken into accountwhenever Siegling Fullsan is used.

Materials
All materials used in the conveyor must satisfy hygienic andmechanical requirements, withstand the corresponding
operating conditions, and where applicable be correct friction partners in interaction with the conveyor belt.

Conveyor components

Materials

Frame

Aluminium
Steel
Stainless steel

Sliding support

Polyamide (PA)Polyethylene (PE)Ultra-high-molecular-weight Polyethylene (UHMW-PE)
Polytetrafluoroethylene (PTFE)
Stainless steel

Drum

Steel
Stainless steel

Scraper

Polyurethane (PU)Side strips

Ultra-high-molecular-weight Polyethylene (UHMW-PE)

Side skirts

Polyurethane, solid (PUR)

Please contact our customer service team if you have any questions.

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Siegling Fullsan Engineering Manual · 02/2023

All Siegling Fullsan Series

Therefore, for the selection and type of materials, it is essential to observe the recommendations in the following table.
During use, also note the expansion/contraction of therespective materials due to temperature (see section 2.2).

2.2	Notes on conveyor construction
Frame and supports
The following aspects should be taken into account in thedesign:– For cleaning, maintenance and repair purposes, all parts ofthe conveyor must be easily accessible. Use simple structures that allow the belt to be lifted up and/or drive/idler
rollers to be easily removed (e.g. swing open designs).

All Siegling Fullsan Series– For easy belt installation as well as quick and convenient
cleaning, take-ups and/or quick-tensioning devices
may also be useful even if the belt is operated without
pre-tension.
–	Match the conveyor design to the selected belt type. All
pulley diameters, transitions etc. should have at least theallowed dmin of the belt (for wrap angles ≤ 15° also dmin/2).
Also pay attention to counter-bending and the spacerequirements e.g. of profiles (flights, sidewalls) etc. Profiles(flights, sidewalls) may require a greater drum diameter
than the belt type on its own (see “Technical information2”, ref. no. 318 and “Siegling Fullsan · Lower cleaning costs,
better hygiene”, ref. no. 259).
–	If the design makes it difficult to fit preassembled belts,
then it has to be possible to make the belts endless on
the conveyor. Alternatively, mechanical belt fasteners canbe used if the application permits.
–	The spatial conditions at the installation site must allow
all planned conveyor functions.

22

Siegling Fullsan Engineering Manual · 02/2023– For all conveyor dimensions, note the belt elongation andshrinkage that can occur during operation. Low temperatures must not result in excessive shaft loads (due toshrinkage) and at high temperatures lengthening must be
accounted for to ensure appropriate transmission of drive
power (see materials table in section 2.1).
–	When designing the belt support in the bottom run, take
into account the weight, length and position of the belt
sagging that can occur depending on temperature. It is
important that e.g. fastening elements, cables and collection trays do not touch the belt in any operating state.

Belt side guides
If required, Siegling Fullsan belts can be guided at the beltedges. Do not use these belt guides to compensate for poor
belt tracking (if necessary, correct the belt tracking as
described in section 2.5).

r6 (0.24)–	Use only the materials specified in section 2.1 with thecorresponding surface finish to minimise abrasion anddrag where applicable to meet hygienic requirements.

15 – 30°

Top view
1–	Use either guide blocks or flange rollers (main dimensions
see figures 1–4). Place the first guide components close to
the end pulley; the next ones at intervals of no more than2000 mm (78.7 in) towards the drive. Use long side guides
or L-shaped supports in the area of infeeds and outfeeds.

250 (1h0)

2

250 (1

0)

3

4

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Siegling Fullsan Engineering Manual · 02/2023

40 (1.6)–	During installation, make sure fastening elements do not
rub against the belt (use countersunk headscrews) andthat hygiene requirements are observed. All guide surfaces should be accurately aligned in the conveyor direction
and perpendicular to the conveyor path.
Support on the underside of the belt is provided by
wearstrips, flat supports or rollers. See section 2.4.

All Siegling Fullsan Series–	At the greatest width that the belt reaches under the
given operating conditions, the gap at the side fromguide components must be at least 3 mm (0.12 in) (fig. 1,
top view).

2.2	Notes on conveyor construction
Conveyor speed
We recommend a soft start and soft stop for the motor for
speeds of more than 20 m/min (65 ft/min), or for loads
greater than 70 % of the max. load.

All Siegling Fullsan Series

Conveyor length

Expansion/contraction
due to temperature
Plastics can expand or contract significantly with variationsin temperature.
–	Make allowances for possible changes in the belt length
and width that occur when the operating temperaturedeviates from the original ambient temperature. Thisapplies both to the belt sag on the return side and lateralclearance on the conveyor frame.

– Components such as guide rails and wearstrips also
The maximum conveyor length is generally limited by thechange size depending on the temperature. Take this into
belt’s maximum tensile strength, but it can also be limited
account for assembly (e.g. by providing elongated holes,
by the effects of elastic oscillation, which should in principle
fixing at only one point, placing slotted parts on sheet
be avoided. This can occur when the belt stretches undermetal edges, etc.) Easy to clean gaps should be allowed
load and causes a slip-stick effect. The slip-stick-effectbetween adjacent parts.
describes the effect of the belt alternating between sliding–	Remember that components and the belt expand at theover and sticking to the slider bed.
same time, so gaps between them may become smallerfrom both sides due to temperature changes.
The determining factors to avoid the slip-stick effect are belt
length, belt speed, loading, and friction. In general, theMaterials tested and recommended by Forbo Movement
higher the speed and the shorter the conveyor, the lower
Systems for various conveyor components are listed in thethe risk of slip-stick.
materials table in section 2.1.

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Take-ups

Quick release tensioning devices

The belt contact pressure on the drive drum that Fullsan Flat
requires to transmit the circumferential force is generated bya take-up that tensions the belt (fig. 1).
Even if no pre-tensioning is required, it can be helpful to use
a take-up, because:

Unlike adjustable take-ups, pure quick-action tensioning
devices do not allow precise adjustment of the tension andbelt sag (fig. 2).

– it can make it easier to fit and remove the belt
– it simplifies and speeds up cleaning processes– it can compensate for temperature and load-dependent
belt lengthening, and if necessary control belt sag
Usually position-dependent take-ups are used. In this case,a pulley is fitted that is adjustable in the conveyor direction(e.g. by screws). It can be moved parallel to the axis to apply
the desired pre-tension or generate the desired belt sag.

Locking swing-open designs are common here. One end of
the conveyor frame (including the pulley) is designed toswing up via an axis-parallel pivot axis. Swinging the device
up completely slackens the belt and forms a large sag. This
makes it much easier and faster to clean the belt and conveyor.
Once closed, the belt is correctly tensioned and in the rightposition again.
Of course it is possible and often useful to combine thiswith a take-up.
All Siegling Fullsan Series

The tensioning range should be calculated so that with thetensioning travel extended 30 %, no pre-tension is generated, and at least the desired pre-tension can be achieved byextending the take-up system out further.
Force-dependent tensioning can be achieved e.g. by meansof a weight load acting via a cable. Alternatively, pneumatic,
hydraulic or spring-loaded take-ups can be used.

1

25

2

Siegling Fullsan Engineering Manual · 02/2023

110

– 12

0°

2.2	Notes on conveyor construction
Scrapers
Often one or more scrapers are sufficient to clean adheringtransported material from the belt during operation.
To ensure trouble-free operation, calculations should
include an extra allowance for drive power.
–	The scraper material should be well matched to the belt
and transported material to prevent unnecessary wearon the belt surface and achieve effective cleaning performance.
–	The best results are normally achieved with co-extruded
scrapers that have a relatively soft scraper lip and rigid
main body. They are recommended for hygiene reasonsdue to their homogeneous structure.

1

All Siegling Fullsan Series–	Scraper to be mounted on cross rigid structure (minimizing bending/deflections) supported by the conveyor
frame.
–	Scraper should be installed as shown with light contact
to the belt. (fig. 1).
–	Set the angle of the scraper according to the drawing(do not fit at 90° to the belt).
– Provide adjustment devices to compensate for wear
in the scraper strip.
–	Readjust or replace worn scrapers. Damaged scrapers
should also be replaced to prevent belt damage.
–	Make sure that the belt is flat in the transverse direction
at the scraper position (e.g. check the small clearance
between the roller and the scraper at the relevant axis)
and does not change its position due to changes in beltsag.

– On the bottom run, so-called plough deflectors are often
used before the end deflector to prevent falling transported material coming between the belt and drum. They
should only lightly touch the belt (fig. 2).
–	Smooth drums without a lagging can be kept clean bysteel scrapers. These scrapers can be positioned close
against the drum surface and modified for the ring shape(e.g. trapezoid shape).

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Siegling Fullsan Engineering Manual · 02/2023

°

20

1
0–

2

11

Side limits
Sidewalls
Encapsulating the product on the sides can be achieved
with sidewalls (fig. 1).
– Provide sufficient clearance from other conveyor
components to avoid contact.
–	Note that in the concave curve (on angle conveyors),
the waves are compressed at the top edge and become
wider across the conveyor direction.

1

Contact-freeSide strips
Side strips are lateral guides for the transported material(fig. 2). They should open in the direction of belt travel(towards the outfeed end) to prevent transported material
getting trapped between the sealing guide (strip) and belt.
– Fit sealing guides at right angles to the belt and only as
close to the belt as the transported material requires.
For material recommendations see the materials table insection 2.1.

2Side skirts
Side skirts drag on the belt and can be used for lightweighttransported material (fig. 3).
This can cause increased wear on the carrying side of thebelt. Profiles (flights) may need to be moved inwards tomake room for them.
For material recommendations see the materials table insection 2.1 or consult your Forbo Movement Systems sales
representative for side skirt material solutions.

3

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Siegling Fullsan Engineering Manual · 02/2023

All Siegling Fullsan Series

Available sidewalls are listed in the Forbo Siegling brochure“Siegling Fullsan · Lower cleaning costs, better hygiene”,
ref. no. 259.

2.2	Notes on conveyor construction
Feeding the transported material
During loading, the conveyor belt is stressed in thevertical (impact) and tangential directions.
You should therefore provide devices that deliver the transported material to the conveyor belt with low impact energy and a speed component in the belt running direction(ideally at the same speed) (fig. 1). Loading should take place
centrally to prevent deflection of the belt (material fed e.g.
by chutes, guide plates, hoppers, feed silos).

All Siegling Fullsan Series

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Deflection of shafts, axes, drums, and rollers (fig. 1)
The belt pull acting on axes and shafts causes deflection.
Large bearing distances and small diameters amplify this effect.

lys– Keep deflection as small as possible to minimize material fatigue
and ensure a small, uniform transfer gap (we recommend keeping
the deflection value ≤ 2 mm).
–	If the belt pull causes greater deflection (> 2 mm), change thedimensioning accordingly or use an intermediate bearing.

The deflection can be calculated using the following formulas:3ys = 5 · Fs · lb
384 · E ·Material[mm, in]
Steel
Stainless steel
Aluminum

with:
ys 	

= shaft deflectionFs 	= shaft loadlb 	= bearing center distance[mm, in]

Round

E 	

= modulus of elasticity[MPa, psi]

Hollow round 	= area moment of inertia[mm4, in4]

Ws 	

= edge length of square shaft[N, lb][mm, in][mm, in]ts[mm, in]

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Siegling Fullsan Engineering Manual · 02/2023

E in

N
MPa =
mm2

[          ][106 psi]

200000180000700000

29.01
26.11
10.15

[mm, in]ds, din, dout = diameter of shaft= wall thickness of shaft

E in

Shaft typeπ · ds4
64
π ·

WS 4
12

SquareHollow square

dout4 – din464

π ·WS4 – (WS – 2 · ts)4
12

All Siegling Fullsan Series

12.3 Belt support on the carrying side
GeneralWhen designing the belt support, also note the general
information in section 1.1 and, where applicable, the noteson hygienic design in section 2.1.
–	Always precisely align the slide supports, as these havea very strong guiding effect on the belt.
– Position the slide supports as shown in the drawings.
– For the slide support, use only the materials listed in
section 1.1. These materials produce favorable friction
characteristics.

All Siegling Fullsan Series–	Thoroughly clean the slide supports before putting theconveyor into service. Otherwise residues of protective
paints or other contamination could cause significant
problems (e.g. tracking issues, belt damage, increased
friction on the running side).
– Consult your contact person at Forbo Movement Systems
if particularly heavy materials are to be transported andhigh point loads occur.

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(0 20.79)

Supporting the belt with flat (table) supports

3 (0.12)

2
(0. 0
79
)

Full-surface table supports are recommended
for systems with heavy loads (fig. 1).
– 	Use only materials according to the specifications in the materials table in section 2.1.
– Carefully round off edges and slightly chamfersliding surfaces in the conveyor direction.

– Fastening elements must not make contact
with the belt.

1

15 – 30°

The design is dependent on the belt type used
and the conveying task. For better hygiene theslider bed and side guides can be designed outof one piece (figs. 2/3).
When designing the drive and idler pulley area,
observe the notes for Siegling Fullsan Flat
(section 2.5).

2 In slider bed integrated belt guides, top view3

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Siegling Fullsan Engineering Manual · 02/2023

All Siegling Fullsan Seriesh15 – 30°

Fullsan Flat

–	The thickness “h” should be at least large
enough to allow fastening elements such as
screw heads to be completely countersunk,and so that the chamfer in the conveyor direction can be formed.
In addition, the thickness is determined by
the static requirements.

(0 20.79)

2.3 Belt support on the carrying side

3 (0.12)

2
(0. 0
79
)

Supporting the belt with parallel wearstrips

All Siegling Fullsan Series

1

32

Siegling Fullsan Engineering Manual · 02/2023h

15 – 30°

Fullsan Flat

100
(4)

100–150(4–6)

x

3 (0.12)100(4)For applications with light loads, parallel wearstrips can beused (fig. 1, left page). Note in this case that the undersideof the belt is subject to increased wear in the area of thewearstrips.
– 	Use only materials according to the specifications in
the materials table in section 2.1.
–	See the figures 1 and 2 for the main dimensions ofwearstrips and their positioning.
–	The thickness “h” should be at least large enough to allow
fastening elements such as screw heads to be completely countersunk, and so that the chamfer in the conveyor
direction can be formed. (Specifications for plastic material.)
In addition, the thickness is determined by the static
requirements.
–	The sliding surface must be flat and aligned in two
directions with the belt run.
– Carefully round off edges and slightly chamfer sliding
surfaces in the conveyor direction.
– Fastening elements must not make contact with the belt.

33

Siegling Fullsan Engineering Manual · 02/2023–	Stagger the joints of the wearstrip sections in the conveyor direction. A gap must be provided between the individual sections in the conveyor direction (dimension “x”)
that can accommodate length changes due to temperature fluctuations and be cleaned easily.
– Check whether sections with flat (full surface) support
are appropriate in the transported material infeed area.
When designing the drive and idler pulley area, observe thenotes for Siegling Fullsan Flat (section 2.5).

All Siegling Fullsan Series2

(0 20.79)

2.3 Belt support on the carrying side

3 (0.12)

2
(0. 0
79
)

Supporting the belt with a V-shaped arrangement of wearstrips

All Siegling Fullsan Series

1

34

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15 – 30°

Fullsan Flat

10–30 °2

10– 	Use only materials according to the specifications in thematerials table in section 2.1.
–	Select the angle and spacing so that the individual
V-shapes reach into one another and support the belt
across the full width.
–	See the figures 1 and 2 for the main dimensions of wearstrips and their positioning.
–	The thickness “h” should be at least large enough to allow
fastening elements such as screw heads to be completely countersunk, and so that the chamfer in the conveyor
direction can be formed. (Specifications for plastic material.)
In addition, the thickness is determined by the static
requirements.

35

Siegling Fullsan Engineering Manual · 02/2023– Carefully round off edges and slightly chamfer sliding
surfaces in the conveyor direction.
– Fastening elements must not make contact with the belt.
When designing the drive and idler pulley area, observe thenotes for Siegling Fullsan Flat (section 2.5).

All Siegling Fullsan Series

0
15
0– )
6
(4–

With a V-shaped arrangement of wearstrips, the belt is supported across its full width (fig. 1, left page). This results ineven wear across the belt width, which means that heavier
loads are possible. At the same time, contaminating particles
can be wiped off the belt underside.

2.3 Belt support on the carrying side
Supporting the belt with rollers
Forbo Movement Systems recommends roller supports only
for Fullsan Flat.
Troughed conveyors are an exception (see section 3).
For conveying unit goods, the support roller spacings are
determined by the edge length of the unit goods beingtransported (25 % of the length of the transported goods).

X

All Siegling Fullsan Series

X/4

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2.4 Belt support on the return side
GeneralThe correct design of the return side is very important for
the trouble-free operation of the conveyor. It is the only way
to ensure the desired (almost) tensionless operation of the
belt.
When designing the belt support for the return side, also
note the general information in section 1.1 and, where applicable, the notes on hygienic design in section 2.1.
–	Determine the values for changes in the belt length andwidth at lowest/highest operating temperature, and takethese into account in the design (see materials table insection 2.1).

– For belts wider than 610 mm (24 in), flights have to be sectioned so that a support can be provided in the returnside (see next page, fig. 3).
– 	Use only materials according to the specifications in thematerials table in section 2.1.

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Siegling Fullsan Engineering Manual · 02/2023

All Siegling Fullsan Series–	Include the design of the return side in all considerations
concerning accessibility for maintenance and repairs, easeof cleaning the conveyor, belt changes, etc.

2.4 Belt support on the return side
Supporting the belt with rollers
Forbo Movement Systems recommends the use of support
rollers to support the belt on the return side. Support rollers
can support either the full belt width (fig. 1) or sections of it(fig. 2/3).
– Preferably use support rollers that support the belt acrossits full width.
– Parallel to the conveyor direction, support is provided
at intervals of 500 – 1800 mm (19.7 – 70.9 in).
–	The roller diameter “D” must not be smaller than thepermissible counter bending diameter of the belt.

All Siegling Fullsan Series– For belts with flights and/or sidewalls, only narrow
support rollers can be used. If a continuous shaft is used,a suitable large roller diameter should be chosen.

50–75
(2–3)

1

50–75
(2–3)

2

6
(0.24)

50–75
(2–3)

Sliding belt supports
Sliding belt supports in the return side, in the form of fixed
wearstrips, slide shoes or slide shafts are often found inpractice (fig. 4). Forbo Movement Systems recommends theuse of support rollers to support the belt on the return side.

3

50—75
(2—3)

4

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All Siegling Fullsan Series
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Siegling Fullsan Engineering Manual · 02/2023

2.5 Fullsan Flat
Drive | Pulleys | Tracking
GeneralThis section contains design information that applies specifically to Fullsan Flat.
For important information applicable to all Siegling Fullsan
series, see sections 2.1 to 2.4.

Fullsan Flat

Drive types
Head driveThis drive type is used for most conveyor functions. The
drive shaft is located at the head of the conveyor (outfeedside) and pulls the belt (fig. 1).
Snub rollers
Use snub rollers if necessary in the return side to increase
the wrap angle at the drive/idler pulley and/or to minimize
the distance between the carrying and return sides (fig. 2).
The diameter of snub rollers can be up to 1/2 dmin as long as
the wrap angle does not exceed 15°.

1

2

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Lower head driveThis is a variant of the head drive where the drive shaft/drum is arranged in a lower position. It means that thesmallest possible pulley diameter can be used at the transfer
point to minimize the transfer gap (fig. 1).

1

Center drive (e.g. Ω-drive)
Due to limitations in top side support on the return way
caused by sidewalls and lateral profiles these are not suitable for center drive applications.
Center drive (e.g. Ω-drive) is typically used when:With a lighter belt load, the wrap angle can be made smaller,
which also gives the conveyor a flatter shape (fig. 3).

– the smallest possible pulley diameters are required at theinfeed and outfeed sides to minimize the transfer gap,
and/orIn both cases, the axes/shafts at the ends of the conveyor
system are under higher loads because the belt pull is present as belt tension on both the tight and slack sides of thebelt.

– reversing operation is required.

–	Arrange the drive shaft in the middle if possible.

Reverse operation is more complex to belt tracking and is
not recommended by Forbo.

–	The belt length between the snub roller and drive should
be shorter than between the snub roller and the next
support roller. Otherwise weight rollers are required in thedesired sag area.

Fullsan Flat

A large wrap angle on the drive produces optimal conditions for reliable power transmission in both running
directions (fig. 2).

2

3

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2.5 Fullsan Flat
Drive | Pulleys | Tracking
Tail drive (pusher configuration)
and alternating tail-head drive
If a head drive reverses direction, it becomes a tail drive(fig. 1).
This means that the drive unit has to push the loaded belt.
In this case, if the return side tension is not greater than the
carrying side tension, the belt may slip on the drive drum.

Rear drives and alternating head/tail drives may require
higher pre-tension.

1

Drive and idler drums
Shaft design
For dimensioning the shafts, see the corresponding paragraphs in section 2.2. As an alternative to a conventionallydrive shaft, a drum motor can be used.

Geometry of drive and idler drums
If the diameter is too small, it will lead to unacceptabledeflection of the drums, particularly on wide systems. This
will cause undesired wrinkling of the belt and poor tracking.
Please do a check calculation. Drum diameters should
always be as large as possible.
The smallest permissible diameter is determined by– the circumferential force to be transferredd– the bending characteristics of the welded-on lateralflights and longitudinal profiles (see “Technical information 2”, ref. no. 318) and “Siegling Fullsan · Lower cleaning
costs, better hygiene”, ref. no. 259).

2

Drive and idler drums can be cylindrical (fig. 2) or conicalcylindrical (fig. 3).

b
h

b/2

Conical-cylindrical drums are particularly useful for shortbelts due to their higher tracking effect. Should the belt
width be significantly smaller than the drum length, the belt
width is decisive for the division of the drive drum.

dFullsan Flat

– the bending characteristics of the belt type used3
Drum dia. [mm (in)]< 200 (7.87)

200 (7.87) – 500 (19.68) > 500 (19.68)

Conicity “h” [mm (in)]0.5 (0.02)

0.8 (0.03)

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1.0 (0.04)

Smooth running surfaces
The running surfaces of all drums should be smoothly
finished.
Excessive grooves will produce an undesired guiding effect.
Roughness RZ ≤ 25 (DIN EN ISO 4287), (roughness depth≤ 25 µm)

Fullsan Flat

Use only drums whose surface was machined in two turning processes from the middle outwards (or from the edges
to the middle). Half of the resulting turning grooves will thenhave a right-hand “thread” and half a left-hand “thread”; theirsteering effects will cancel each other out.

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2.5 Fullsan Flat
Drive | Pulleys | Tracking
Belt tracking
Conveyor design and condition
The conveyor frame should be as rigid as possible. It mustnot be distorted by the forces exerted by the belt. If the axes
are not arranged at right angles to the belt conveyor direction, the belt will run off track (fig. 1).

– clean and in a good condition,¡90

All rollers, drums and shafts in the system as well as
supports and guide elements should be:1– aligned axially parallel and at right angles to theconveyor direction,– aligned laterally in relationship to one another.

Effect of temperature
Strong asymmetrical heating and loading on a properly
adjusted belt can cause uneven changes in the belt’s innertension.
This creates steering forces which could cause the belt
to run off track. In these cases, an automatic belt tracking
system is recommended.

Alignment at a 90° angle

Fullsan Flat

–	Align the conveyor torsion-free and adjust all axes andshafts so that they are horizontal (measured across theconveyor direction).

L1
L1
a
a

–	Measure the diagonal distance ”a“ between the ends asshown in the drawing. If the distances are equal, the alignment is correct. Make sure that the distances in the conveyor direction are correct after alignment (fig. 2).
–	If the shafts are too far apart or obstacles are in the way,
you can measure the distance ”b“ between ends and apoint “A” on the center line of the conveyor (fig. 3).

2
L2
L2
b
b
b
b

3

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Siegling Fullsan Engineering Manual · 02/2023

a
a

A
A

Belt tracking at the pulleys
Drums, rollers and shafts should be arranged adjustably tocompensate for manufacturing tolerances in the system andbelt (fig. 1). If satisfactory belt tracking cannot be achieved inthis way, options include using slanting rollers or automatic
belt tracking systems.
For so-called “undersquare” systems (axis distance ~ belt
width) or an even worse length/width ratio, the belt can nolonger be adjusted via conical-cylindrical or crowned drums.

1

A

B

Adjustment– Fit the belt, align pulleys A + B axially parallel, andcreate the desired sag in the return side.
– Correct the belt tracking by increasing or reducing thetension on one side of the drive shaft B. The belt will
move towards the less tensioned side.
–	It may be necessary to use a belt tracking system near
the end drum (e.g. for wide, short belts).

Belt tracking with snub rollers
A very effective way to track the belt is to use snub rollers
C, D (fig. 2).

X

45

Y

The snub rollers should be adjustable
only in direction X Y (belt run-on andrun-off point). That way, the beltedges are hardly affected at all. Highly
effective automatic belt tracking control can be implemented with the aidof motorized adjustable snub rollers.

Siegling Fullsan Engineering Manual · 02/2023

2

1

A

B
C

D

2

Adjustment–	Set axes and shafts axially parallel as a basic setting.
– Fit the belt with the correct sag in the return side.
– Correct the belt tracking via drum C or D. A belt tracking system using drum C or D as the control drum may
be required.

Fullsan Flat

The greatest tracking effect is always exerted by the snubroller where the return side meets the end pulley.
if the belt runs in direction 1, snub roller C.
if the belt runs in direction 2, snub roller D.

2.5 Fullsan Flat
Drive | Pulleys | Tracking
Belt tracking with center drive/Ω-drive
Snub pulleys G and F as well as the drive shaft E are adjustable in the direction of the arrow (fig. 1).
As a simple design solution, the mounts for G, F and E canbe installed on a plate H which is moveable along thereturnway.
For the arrangement, design and control characteristics ofdrums A, B, C and D, see the previous and next pages.

A

D

G

F
E

C

B

H

1

Adjustment–	Set axes and shafts axially parallel as a basic setting.
– Fit the belt with the correct sag in the return side.
– Correct belt tracking via the snub roller C and if necessary via the bend pulleys G and F or plate H. A belt
tracking system may be required here too.

Belt tracking with reversing systems
The precision with which the system and belt are manufactured is important for trouble-free belt tracking in reversing
operation.

Fullsan Flat

It is not easy to adjust the belts correctly in reversing operation. Once the conveyor belt is adjusted correctly in one
conveyor direction, it often runs off track in the other conveyor direction. It takes some time to adjust the drums
correctly (fig. 2).

2

1

A

B
C

D

2

Adjustment–	Set axes and shafts axially parallel as a basic setting.
– Fit the belt with the correct sag in the return side.
–	In reversing operation, the belt tracking should be
adjusted not at the snub rollers but at the end pulleys.

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Effect of support rollers
For troughed belts, tracking can be improved byrotating the side rollers at some roller stations forwards by up to approx. 3° in the direction of belt
travel, depending on the belt speed (fig. 1).
You can often control non-troughed belts adequately by installing some horizontally adjustablesupport rollers, then pivot them forwards by
about 2 – 4° (fig. 2).
The effect of supporting rollers can mainly be
used with long belts.

A

A

A-A
1

2

Effect of negatively troughed roller sets
A negatively troughed roller set in the return sideis very effective at centring the belt, if it is positioned close to the tail drum (fig. 3).

B

B-B

3

Belt edge sensors
Different types of belt edge sensors are available,
e.g. mechanical, hydraulic, electrical, optical andpneumatic. They activate the the belt tracking
system when the belt edge position changes.

Automatic belt tracking
Automatic belt tracking systems are often used with tilting snub rollers.
They are usually adjusted by means of electrically operated threaded
spindles or pneumatic cylinders according to the current belt edge
values detected by the belt edge sensors.
Purely mechanical solutions without auxiliary energy are also possibleon small systems.

47

Siegling Fullsan Engineering Manual · 02/2023

Fullsan Flat

B

2.5 Fullsan Flat
Drive | Pulleys | Tracking
Absorbing lateral forces with longitudinal profiles
Lateral forces arising e.g. due to transported material entering or exiting from the side can be absorbed by welded-on
longitudinal profiles in the conveyor path support area.
1.5 (0.06) x 45°– For systems with a length/width ratio of less than 2, thebelt can be guided by grooves in drums/taper rollers.
If the ratio is greater than 2, it should be guided bygrooves in the table or between wearstrips so that the
profile does not climb up the edge of the groove anddestroy the belt (fig. 1/2).

Z = 4 – 5 (0.16 – 0.2)

1.5 (0.06) x 45°–	The grooves for longitudinal profiles should be at least
8 – 10 mm wider and 2 mm deeper than the profile.
The large amount of play enables adjustment of the belt
without it immediately rubbing at the sides.
–	If heavy soiling is anticipated, increase the groove depth.
– For minimum belt lengths and details of profile
dimensions, types and minimum drum diameters, see“Technical information 2”, ref. no. 318.
– For large lateral forces, provide an automatic tracking
device.

Z = 4 – 5 (0.16 – 0.2)

1 Guiding by central guide profile

1.5 (0.06) x 45°
Z = 8 – 10 (0.32 – 0.39)

Do not fix guide strips until the belt is running properly.
A minimum play as specified in section 2.2 must remain
to allow for tolerances.

1.5 (0.06) x 45°
Z = 8 – 10 (0.32 – 0.39)

Fullsan Flat

2 Guiding by laterally mounted guide profiles

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Fullsan Flat
49

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50

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3 	Conveyor layouts

3.1 Horizontal conveyors
3.2 Incline/decline conveyors
3.3 Hockey-stick and swan-neck conveyors
3.4 Troughed conveyors

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3.1 Horizontal conveyors
General
In conveyors that are aligned horizontally, the conveyor beltruns around two end pulleys, one of which is a drive pulley.
The idler can be used as a take-up.

Preferably the drive is located at the outfeed side of theconveyor. In this case it is called head-end.
With this arrangement, the transmission forces are applied
more efficiently than with a tail drive.

Conveyor layouts
Up to length of 2000 mm, horizontal conveyors can be
designed without belt supports in the return side (fig. 1).
With axis intervals > 2000 mm, belt supports (preferably
return rollers) should be fitted in the return side (fig. 2).
This prevents excessive sagging due to the belt’s own
weight.

–	Use the belt sag to compensate for belt length changes
due to temperature and load fluctuations. Specificallyplan the longest unsupported section as a buffer zone forbelt expansion.
See section 2 “Conveyor design” for all design details.

Fullsan Flat

1 Shown without optional snub roller/pressure roller

Fullsan Flat

2

52Shown without optional snub roller/pressure roller

Siegling Fullsan Engineering Manual · 02/2023

3.2 Incline/decline conveyors
GeneralIn straight incline/decline conveyors (without a change ofangle), the conveyor belt runs around two end pulleys, oneof which is a drive pulley. The idler can be used as a take-up.

The design of the drive depends on the conveyor direction(incline or decline). Conduct your own experiments to determine the conveyor angle that can be realized for your conveying task, and consider the use of sidewalls and/or flights,
if necessary.

Incline conveyor (fig. 1)
Generally we recommend the following:–	Use only a head drive(i.e. use the upper shaft as the drive shaft).
–	Ensure there is always a screw tension take-up system
or force-dependent take-up on the tail, since the belttension (generated by the belt sag) decreases with anincreasing conveyor angle.
–	If the belt width is wider than 600 mm, we recommend
providing additional supports on the belt surface or
between the flights in the return side.

Fullsan Flat

See section 2 “Conveyor design” for all design details.
1

Decline conveyor (fig. 2)
Generally we recommend the following:–	Drive type head drive–	Ensure there is always a screw tension take-up system
or force-dependent take-up on the tail, since the belttension (generated by the belt sag) decreases with rising
gradient.
–	If the belt width is wider than 600 mm, we recommend
providing additional supports on the belt surface or
between the flights in the return side.
–	In case of heavy load a tail drive configuration can berecommended.
See section 2 “Conveyor design” for all design details.

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Siegling Fullsan Engineering Manual · 02/2023

Fullsan Flat2

3.3 Hockey-Stick andswan-neck conveyors
GeneralA hockey-stick conveyor (L-conveyor) has a horizontal conveyor section in the lower part of the conveyor, and a conveyor section with a gradient angle (fig. 1). The conveyor
direction is usually upwards. A head drive is usual. If there islimited space around the head drum, a tail drive can work
but is generally not recommended.
The belt undergoes at least one counter bend due tocontact with guide elements on the carrying side.

A swan-neck conveyor (Z-conveyor) has a horizontal conveyor section at the bottom of the conveyor, a conveyor
section with a gradient angle, and a horizontal section at
the top of the conveyor (fig. 2). The conveyor direction isusually upwards. If there is limited space around the headdrum, a tail drive can be used. In this case, the tensile forcesin the belt can only be small, since the concave bending in
the return side is critical.
		
The belt undergoes at least two counter bends due to contact with guide elements on the carrying side. With thisarrangement, the transmission forces are applied more efficiently than with a tail drive.

Convexcurve

Concavecurve

Concave
curve

Fullsan Flat

1

54

Fullsan Flat

2

Siegling Fullsan Engineering Manual · 02/2023

Use of profiles (flights, sidewalls) and bending/counter-bending radii
For incline conveying, it is often useful to equip conveyor
belts with profiles (flights, sidewalls) (fig. 1).

➁– Lateral flights (1) ensure that the transported material is
carried on the belt➀

– Sidewalls (2) enclose the belt’s conveying area at the sides➁– Longitudinal profiles positioned centrally on the running side (3) ensure central tracking of the belt
– Longitudinal profiles at the edges of the belt on therunning side (4) or on the carrying side (5) are required for
guidance and to ensure a constant width if the transverse
rigidity of the belt including any welded-on sidewalls is
not sufficient to keep the belt laterally stable in the concave curve.

➃
➂
➄

➄

In these cases, the minimum bending/counter-bendingradii are dependent not only on the belt type but also on
the profiles (flights, sidewalls) that are used.

1

Drive
Hockey-stick and swan-neck conveyors almost exclusively
use head drives. The upper drum is used as the drive drum,
and is provided with a friction coating (Fullsan Flat). The
motor should be designed for low accelerations, as otherwise many system components can be placed under excessive loads.
–	Ensure there is always a screw tension take-up system orforce-dependent take-up on the tail, since the belt tension (generated by the belt sag) decreases with anincreasing conveyor angle.

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3.3 Hockey-Stick andswan-neck conveyors
Belt guidance in the concave curve(top side of belt)
Forbo Movement Systems recommends roller support on any
counter-bending/transition section of the conveyor.
–	Use hold down rollers (fig. 1) having the permissible dmin to holddown the belt edge (minimum width “B” in each case 30 mm (1.2 in);> cylindrical rollers (1) for belts without longitudinal profiles on the
carrying side,> V-pulleys or guide rollers (2/3) for belts with longitudinal profiles
on the carrying side (guide profiles).
– Forbo Movement Systems does not recommend the use of skids orwearstrips.
–	When using sidewalls and/or lateral profiles, the smallest permissible
deflection diameter increases if the dmin of the sidewall/profile islarger than the dmin of the belt on its own (for values see “Siegling
Fullsan · Lower cleaning costs, better hygiene”, ref. no. 259).

➀

➁

B

B

➂

B

1

–	When using V-shaped profiles, the smallest permissible deflection
diameter increases if the dmin of the profile is larger than the dmin of
the belt on its own (for values see “Siegling Transilon · Technicalinformation 2”, ref. no. 318).
– Between the belt supports and profiles/sidewalls, allow a gap at theside of at least 6 mm (0.25 in) (fig. 2).
– For belt widths exceeding 600mm, additional support rollers arerecommended on the return side. In these cases, gapped flights are
required.

2

For low and unchanging gradient angles, it is sufficient to use onepressure roller (4) on each side of the belt (counter bending radius see
above) (fig. 3).
For larger and changing gradient angles, multiple pressure rollers (5)can be used at each side of the belt (at least three). Their diameter canbe smaller than when using a single roller per side. An overall deflection radius of > 200 mm must be maintained, however, since the arcs
of contact at the local deflection points could cause breaks in the
spliced area of the belt (fig. 3).

r>

200
mm

➃

➄
3

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Belt guidance in the convex curve(underside of belt)
Especially if the belt is operated dry without lubrication,high friction resistance occurs at this bending point.
– Preferably (depending on the belt type) use rollers as an
end pulley that meet the permissible dmin across the full
width of the belt (fig. 1).

r>

200
mm

– Forbo Movement Systems does not recommend the useof skids or wearstrips (fig. 2).

1

2

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3.4 Troughed conveyors
GeneralFor transporting bulk solids, conveyors with troughed belts
are frequently used. These can operate horizontally or at a
gradient. Design the trough cross-section according to thebelt type used and the conveyor width/task. The idler canbe used as take-up.

Transitional area between
end pulley and troughPreferably the drive is located at the outfeed side of theconveyor, in this case called the head-end.
With this arrangement, the transmission forces are applied
more efficiently than with a tail drive.

Trough angle

Where the troughed belt transitions from the drum onto the
supporting rollers (and vice versa), the edges are subjected
to increased elongation (fig. 1).
Therefore please observe the guide values listed in the table
for the transition length Is.

Possible trough angles depend on the belt width:
Belt width < 300 mm
trough conveying
			not recommended
Belt width 300 – 500 mm trough angle up to 30°
Belt width > 500 mm
trough angle up to 45°
Depending on the Siegling Fullsan type used, different
trough shapes can be realized (see following pages).

Is = belt width b0 · factor c7[mm]

Trough angle

15°

20°

30°

40°

c7

0.7

0.9

1.5

2

W

Is

1

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Siegling Fullsan series and trough shape
The possible trough shape and belt support design dependon the conveying task and the Siegling Fullsan type used.

Belt support for Fullsan Flat (fig. 1)–	The belt can be supported by wearstrips, full-surface
and by rollers (U-shaped, V-shaped or round).
– 	Use only materials according to the specifications in thematerials table in section 2.1.

U-shaped
trough(wearstrips)– For all types of belt support, observe the main dimensions
in the drawings opposite and in section 2.3.

W–	Rollers should extend outwards at least to the edge of thebelt. The spacing in the conveyor direction is normally
between 400 mm and 700 mm (15.7 and 27.5 in).
–	Integrate side guides if necessary.

V-shaped
trough(wearstrips)–	Make sure that the transitions in the regions at the beginning and end of the trough are well rounded.

W–	The top edges of the head and tail pulleys and the middle
trough plane must lie in one plane. If the trough bottom
is not supported by a wearstrip, a maximum sag of 30 mm(1.2 in) is permissible.

Roundtrough(wearstrips)W

400 – 700 (15.7 – 27.5)

Examplesfor different
troughdesigns1
Principle diagrams for different trough designs

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Siegling Fullsan Engineering Manual · 02/2023

Legal Notes

Forbo Siegling GmbH (“Forbo”) provides this Engineering
Manual for information purposes only. While Forbo endeavors that its recommendations, operating instructions, details
and information on suitability and use of our products are as
accurate and complete as possible, Forbo does not makeany representation or warranty of any kind whatsoever,neither expressed nor implied, with respect to any information contained in this Engineering Manual unless otherwise
expressly set forth in writing by duly authorized representatives of Forbo. It is your sole responsibility to perform appropriate testing of our products and their merchantability andfitness for a particular purpose, and Forbo does not accept
any liability for any damages, including but not limited toproperty damages and personal injury, in connection withyour reliance on any information contained in thisEngineering Manual or any technical and/or other support
which Forbo may have provided to you.
This Engineering Manual is Forbo property. Any reproduction, transmission or other use of this Engineering Manualor part(s) thereof is only permissible with Forbo’s writtenconsent.
Forbo reserves the right to modify the content of thisEngineering Manual at any time and without prior notice
to you. The latest version of this Engineering Manual canbe downloaded from our website.

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Siegling – total belting solutions
Committed staff, quality oriented organization and­production processes ensure the constantly high standardsof our products and services.

Our service – anytime, anywhere
Forbo Movement Systems employs around 2,500 people in its
group of companies. Our products are manufactured
in ten production facilities across the world.
You can find companies and agencies with warehouses andworkshops in over 80 countries.
Service points are located in more than 300 places worldwide.

Forbo Siegling GmbH
Lilienthalstrasse 6/8, D-30179 HannoverPhone +49 511 6704 0
www.forbo-siegling.com, siegling@forbo.com

02/23 · Reproduction of text or parts thereof only with our approval. Subject to change.

Ref. no. 443-2

Forbo Movement Systems complies with total quality management principles. Our quality management system has
ISO 9001 certification at all production and fabrication sites.
What’s more, many sites have ISO 14001 environmental
management certifi­cation.