Conveyor Components

Conveyor Components - Overview

COMPONENTS_297 17.8.2004 20:43 Stránka 3

3

" Idlers " Pulleys

"Covers "Cleaners

"Measuring Systems "Conveyor Structures


Continuous transportation of bulk materials relies on a faultless conveyor system.A malfunction of just one conveyor component can delay all material productionand therefore the reliability of each conveyor component is vital. The idleris one such component, and as idlers are present along the entire length ofthe conveyor, they demand particular attention. The idler is defined as thecomplete assembly comprising of the base frame and/or brackets, and rolleror rollers. The roller is the heart of an idler and is defined as the revolving,cylindrical part of an idler, complete with shaft, bearings and seals. The idlersare attached directly to the conveyor frame. The belt follows this geometryand an effective profile for conveying bulk material is formed.

It is our aim to deliver reliable rollers, the parameters of which exceed currentindustrial standards for all three of these principal functions.

TRANZA saw the need to improve the design of rollers in line with technologicaladvances and customer demand for more economical solutions. TRANZAhas met this challenge with innovative designs of rollers and other componentsincorporating many features specifically developed within the company.Our research and development has led to the production of EasyRun®

rollers which carry larger tonnages at greater speeds, consume less energy andare immune to aggressive environmental conditions (dirt, dust, rain, and largetemperature differences).

The three principal functions of each roller are to:

" Support the belt

" Rotate to keep the belt moving smoothly

"Work reliably under the hardest of conditions, with low energy consumption, for as long as possible

EasyRun® Rollers and Idlers - Concepts


- Flat rollers (type F)

- Rubber-lagged rollers (type R)

- Impact rollers (type I)

- Training rollers (type T)

- Return disc rollers (self-cleaning, type D)

- Return spiral rollers (self-cleaning, type S)

The rollers are standardised and designed according to ISO 1537, DIN 15207 and DIN 22112.Rollers according to BS and SABS or custom made rollers are available onrequest. Tranza is capable of delivering a range of special-design rollers: waterproof rollers, rollers for extreme climate conditions, rollers for extreme loading, high speedrollers and case-hardened rollers.

Rollers EasyRun® Product Range


7

TROUGHING CT

CV

CC

CF

CG

VEE

CANTILEVER

FLAT

BRACKETS

GARLAND

CARRYING SETS

RETURN SETS

TRAINING SETS

IMPACT SETS

CENTRING SETS

SELF-CLEANING SETS

The idlers are standardised and designed according to DIN 22107, and on request according to CEMA 502-2001 (B, C, D, E), SABS, BS. TRANZA is capableof delivering unique idlers made from fibreglass composites which combine high strength with low specific weight and excellent anticorrosion and antistatic properties.TRANZA also offers a range of special-design idlers: idlers for extreme climate conditions, for extremely heavy-duty applications, specific load distributions and zero gap idlers.

Idlers

CB

SRV

SRF

SRG

SRB

IT

IG

TCT

TRV

TCF

TRF

CCT

CCVRV

RC

RF

RB

EasyRun® Product Range


Drum style pulleysLagging:

- Steel (no lagging)- Rubber - smooth

- herringbone pattern (clockwise sense)- herringbone pattern (anticlockwise sense)- diamond pattern

Wing style pulleys-

Squirrel cage style pulleys

The pulleys are standardised and designed according to ISO 1536.

Pulleys Product Range


9

Accessories

Covers- Corrugated steel (DIN 59231)- Organit rigid PVC

Cleaners- Carrying side cleaner

- Return side cleaner

Product Range

Volume measuring systemAn optical belt sensor measures material ondischarge conveyors by sending a beam.The receiving cameras pick up the sent beam and the computer checks and analyses the data.

Modular conveyor structuresStructures are made from steel for difficult conditions in underground operations. Special corrosion-resistant, non-flammable structures made from pulltruded fibreglass composites, which are suitable for environments where there are risks of explosions, are also available.

- Roof slung- Floor mounted

- Combined (roof/floor)


The main components of a conveyor roller that influence its functional reliability and service life are:

Rollers


11

A) ShellThe shell is usually a steel tube of adequate thickness and diameter to matchthe required use. The shell is in direct contact with the belt and may wearexcessively when rotational speed differs from belt speed. This can lead to shellthickness failure and finally to the shell collapsing. The wear can be attributed to:Misalignment (if rollers are not fitted perpendicular to the belt line rubbing of the beltover the roller shell surface results in premature failure).Contaminants (the action of grinding hard particles between the belt and theshell can cause an increase in the amount of wear on the shell).

B) ShaftThe shaft is the load bearing element of the roller and must be adequately sized according to load and roller length. It is very important to ensure thebearing and shaft assembly operates under deflection conditions. The shaft isonly supported at each end and therefore must accept the load from the shell tothe bearings at each end. This results in shaft bending and angular deflectionof the bearings. Solid accurately machined bright mild steel provides greaterstrength and less deflection.A circlip (F) positively locates the shell to the shaft and minimizes shaft float.

C) Bearing housingThe bearing housing is made of deep drawn steel with a collar flange andcalibrated bearing bore sized to a tolerance of ISO M7. The shape of thecollar flange reinforces the corners of the shell. Plummer block housings areavailable on special request.

If the manufacturer uses an end disc then the method of attaching the end discto the shell is a very controversial issue in the industry. Some manufacturers buttthe end cap up against the roll end and weld a fillet weld around the roll. Somemanufacturers counterbore the end of the roll, inset the end cap inside the roll,and weld a fillet weld around the inside of the roll. With the first method there is

certain risk of separation caused by either wear, corrosion, or mechanical failure of the joint between the shell and the end cap and this may result in a sharpedge of the end cap causing damage to the belt - "pizza cutter effect". Thedrawback of the inset weld is that some wear thickness is removed in thecounterbore process. If the shell did wear in this area it would reach the enddisc more swiftly than in the case of the exposed fillet weld roll.

D) Internal sealing ringServes for sealing the bearing and restricting the ingress of impurities from theinternal area of the roller. It also prevents the escape of lubricating grease fromthe bearing into the internal area of the roller.

E) BearingOnly radial ball or tapered roller precision bearings are used. Ball bearings aremore cost effective as tapered roller bearings have significantly higher CEMAAi values (the force required to overcome frictional resistance and rotate rollers).On long horizontal conveyors this can represent noteworthy savings in powerconsumption as well as increasing the service life of associated drive components.Probably the most common type of roller failure is a seized bearing. Bearing seizure can be down to the following: - Selection of incorrect bearings may cause overloading of the bearingand its collapse.

- Incorrect tolerances for the bearing fit may result in the bearing overheating.

Design and Components


- If the bearings are misaligned (not fitted square and concentric with the shellof the roller)

- Damage to the roller or idler frame when forced into idler frames on site- Seal failure resulting in contaminants entering the bearing

F) Circlip- Manufactured from hardened spring steel in compliance with DIN 471- Minimises shaft float

G) The labyrinth sealing system- The system comprises of several sealing elements which prevent contaminantsfrom entering the bearing

- Individual elements of the system are circular in shape with interlaid lipswhich form a labyrinth

- The shape of the lips is designed to prevent the intrusion of contaminantsinto the bearing chamber without increasing rotational frictional resistance

- The system has two parts - an inner labyrinth (H) and an outer labyrinth (I)protected by a cover (J) and a shaft ring (K)

- Various types of labyrinth sealing system can be supplied depending oncustomers’ individual requirements

LubricationLubricants in bearings have the following roles:To prevent direct contact between the rolling elements, race ways and cagesTo prevent bearing corrosion and wearTo prevent the ingress of contaminationTo cool the bearingsLithium based grease is used to lubricate all parts of the sealing system for life.

Design of the rollerThe diameter of a roller and its shell thickness can drastically affect a rollers life.Selecting a larger diameter reduces the rpm of the bearing as well as increasingthe wearable surface area of the roller.Roller concentricity is important in providing smooth running and an even wearpattern for rolls and belt. A roll that does not rotate concentrically with the shaft willintroduce vibration within the bearing that will decrease bearing life. A key issue in roller performance is drag. It is important to avoid drag as it canincreases power consumption and affect the life of the roller.Accurate design of each detail of a roller and advanced technology used in finalassembly are required to ensure the reliability and high performance of rollersand consequently conveyors.

Standard design Standard design with additional platecover and rubber seal for very dustyand humid conditions

Standard design with additional platecover for harsh conditions

Sealing System Sealing System Sealing System

Design and ComponentsRollers


TRANZA concentrates on the critical points in roller design.Our efforts lead to the achievement of the best roller parameters in the industry. Throughout the design, manufacturing and testing process we utilise sound engineering principles to supply the best possible products to our customers.

A fundamental parameter permanently evaluated byTRANZA is T.I.R. (Total Indicator Runout) which reflectsimbalance and reduced life of rollers. Significant effort isfocused on decreasing T.I.R. This approach producesTRANZA rollers with the following features:

" Low vibrations, low noise" Reduced power consumption (to start and run the

conveyor)" Min. 30.000 hours standard life time" Competitive prices

Besides T.I.R. measurements Tranza also keeps a standardset of tests in order to benchmark its rollers with those ofcompetitors so that it can continuously improve the performance of its rollers. This standard set of tests is usedto monitor all issues which influence key features of EasyRun®

rollers and includes:

" Load capacity tests" Wear tests" Sealing against water and dust tests" Start and run resistance tests

Benefits of EasyRun® Rollers


15

The extraordinary level of balance, performance and lifetime achieved by TRANZA is a direct result of the attention itpays to the details of the design and manufacturing process:

" Precision tolerances of the bearing housing (M7),shaft (h6) and bearing ensure the precondition ofauto-alignment of the outer and internal bearing rings

" Unique and precise assembly procedure provides for excellent balance of rollers and precision of alignment

" Expertise in choosing correct components esp. bearingsfor specific applications

" The bearing and shaft assembly operates under deflection conditions

" Variety of seals

" Shafts are manufactured from highly precise steel rods

" Highly precise steel tubes are used for shells

" Calibrated collar flange bearing housings avoid the "pizza cutter effect" and reduced wear thickness andresult in higher roller load capacity

" Rollers and their components are permanently testedthroughout the manufacturing process

" Every roller is test run after final assembly at an equivalent belt speed of nine (9) metres per second.


EXAMPLE:Flat roller, diameter of shell 89 mm, length 600 mm, bearing 6204, double flat shaft ends, yellow polyester powder coating RAL 1003:F - 089 x 600 / 6204 / A / PP.1003

Z

111

2222

BBBB

X

YY.3333

444

55

Type code (see Table 1)

Diameter of the shell in mm

Length of the shell in mm

Bearing code according to ISO 15

Shaft end code (see Table 2)

Coating code (see Table 3) followed by RAL colour code

Diameter of rubber lagging/ring/disc (for R,I,D rollers only) in mm

Number of rubber rings (optional - for R and D rollers only)

Z - 111 x 2222 / BBBB / X / YY.3333 / 444 x 55

TABLE 1: Type Codes

F

R

I

T

D

S

Flat

Rubber-lagged

Impact

Training

Return disc (self-cleaning)

Return spiral (self-cleaning)

DESCRIPTIONCODE

Rollers


17

PP Polyester powder

DESCRIPTIONCODE

AC Anti-corrosive synthetic primer coat

WD Water diluted

SZPainting system:

zinc-phosphate primer coat + synthetic-polyurethane top coat

SEPainting system:

two-component epoxy primer coat + epoxy-polyurethane top coat

A Double flat

DESCRIPTIONCODE

TABLE 2: Shaft End Codes TABLE 3: Coating Codes

B Internal double flat

C Bush

D Garland

E External thread + nut

F External thread

G Internal thread

H Single flat

DESCRIPTIONCODE

I Internal single flat

J Plain

K Plain reduced

L Internal reduced plain*

M External reduced thread

*For training rollers only

EasyRun® Ordering Codes


The idler is comprised of the base and/or brackets and one or more rollers and is fixed to the conveyor structure. There are several types of idlers and eachhas a different function and different location on the conveyor.

Carrying SetsThe first group of idlers covers carrying sets which support the loaded section of the belt and move the material. They are located in the upper part of the conveyor.

Carrying Troughing (CT)

" Most carrying sets have a troughing shape which allows greater amountsof material to be conveyed. These shape the belt to prevent spillage andare available with 20°, 30°, 35° and 45° trough angles with equal or unequal roller lengths. Troughing carrying sets have 3 rollers supportedwithin the base frame which is fixed to the conveyor structure. Normalspacing is 1 to 1,6 m.

Carrying "Vee" (CV)

" This type of idler is used in less demanding environments where belt speedsare generally less than 2,5 m/s. It is designed for transporting small grainmaterial (gravel, sand). Owing to the shape of the trough it has a lowertransportation output than a troughing idler however this is compensated for by its lower cost (amongst other things there is a 1/3 lower needfor rollers).

Idlers


19

Carrying Cantilever (CC)

" This idler comprises of a central bracket and two rollers without side brackets.It is designed for less demanding environments and short length conveyors(e.g. discharge conveyors of screeners). They are advantageous due to

their significantly lower demand on space.

Carrying Flat (CF)

" These have a single roller supported by two brackets fixed to the conveyorstructure. They are used in picking, sorting and unit materials handlingapplications. Load capacity is much less than that of troughing idlers becauseof the long shaft length and only two bearings.

Carrying Bracket (CB)

" These are designed for use in low speed belt conveyors for light loads.Their simple low-weight design means they are low priced.

Carrying Garland (suspended) sets (CG)

" Consists of several (3 or 5) rollers, attached together by a chain link.Contrary to troughing sets the maximum angle of the side rollers is 60°.This design leads to greater flexibility of the structure which results in improvedbelt centring, load containment, higher working speeds and load capacity,better absorption of dynamic stresses during conveying large bulky material,less shut down time and lower installation and maintenance costs.

EasyRun® - Types and Functions


Return SetsThese are located in the bottom part of the conveyor and support the belt on its return from the discharge point to the tail pulley. The designs of return sets areessentially the same as for carrying sets:

Return "Vee" (RV)

" Used for the return branch of larger width belt conveyors. It is fitted with apair of flat rollers which are angled at 10° from the horizontal.

Return Cantilever (RC)

" This has the same structure as the carrying cantilever but is used for the returnbranch. It is used for smaller width belts and lower speeds. Its advantage isthat it is attached centrally therefore not requiring a supporting steel sidestructure as required by the other types of idlers.

Return Flat (RF)

" This idler is for supporting the return branch of the belt where a single rollertable is sufficient from the technical point of view but where a set of bracketsare not sufficient from the strength point of view.

Return Bracket (RB)

" This is one of the most popular means used for mounting rollers to support thereturn branch of the belt. It is preferred for belts up to 1400 mm in widththanks to its simple design and affordable price.

Idlers


21

Special SetsThese are designed to have different functions. Each function determines the design of the idler but the actual shapes of carrying and return sets generallyremain the same.

Impact sets

" Their function is to ensure maximum belt protection for the optimum servicelife. Impact idlers are positioned at the loading points where bulk materialfalling onto the belt could cause damage to it. Impact sets are equippedwith rubber-lagged rollers or impact rollers with a number of rubber rings of appropriate thickness and resistance.

Impact Troughing (IT)

" These idlers are designed for use in places where material is droppingfrom a height (hoppers)

" Two types are produced:- Section frame (same as CT idlers)- Tube frame (special double-pipe structure)

" Use of a specific type depends on loading parameters (loading capacity,grain size)

" Both types are fitted with rubber-lagged or impact rollers for damping theimpacts of falling material

Impact Garland (IG)

" These are designed for use in places where material is falling from a height(hoppers) onto conveyors fitted with garland sets.

" They are fitted with impact rollers

EasyRun® - Types and Functions


Idlers

Carrying or return belt training sets (TCT, TCF, TRF, TRV)Troughing or flat idlers assist in keeping the conveyor belt centred on the conveyorwhen temporary or transient conditions could result in belt misalignment. Twosmall side rollers attached vertically to the base frame provide for self-alignmentof the belt. Training sets are generally spaced 30 m apart and not within 15 mof the head or tail pulley. The effectiveness of trainer sets is enhanced by theuse of urethane rollers.

Centring idlers

Centring Carrying Troughing (CCT)

" These idlers are used for supporting the carrying belt" They have a centring effect caused by a slight incline of the axes of the side

rollers (approx. 2°)" They have the same function as training idlers but they are used on smaller

dimension belts (for belt lengths up to 100 m). If they are used they shouldbe fitted along the whole length of the conveyor.

Centring Carrying "Vee" (CCV)

" These are designed for supporting the carrying belt." They have a centring effect caused by a slight incline of the axes of the rollers

(approx. 2°)" They have the same function as training idlers but they are used on smaller

dimension belts (for belt lengths up to 100 m). If they are used they shouldbe fitted along the whole length of the conveyor.


25

The correct choice of idlers is essential for proper performance of theconveyor. The following parameters play a key role in choosing idlers:

Load parameters" Characteristics of the load (lump size, material abrasiveness, humidity)

" Total load capacity

" Type of conveyed material

Environmental requirements" Temperature range

" Others

Conveyor parameters" Belt speed

" Belt type

" Position/function of the idler in the conveyor

Decades of experience allow our experts to guide our customers throughthe whole idler selection procedure. It is part of Tranza’s mission to ensurethat you choose the correct idlers.


TABLE 4: Idler shape/function codes

CT

CV

CC

CF

CB

CG

RV

RC

RF

RB

Carrying troughing

Carrying "Vee"

Carrying cantilever

Carrying flat

Carrying bracket

Carrying garland

Return "Vee"

Return cantilever

Return flat

Return brackets

DESCRIPTIONCODE

C A R R Y I N G S E T S

R E T U R N S E T S

AAA

B

B

1111

22

22

22

C

DD.3333

Idler shape/code (see Table 4)

Frame design code (see Table 5)

0 for garlands

Belt width in mm

Angle of rollers in ° for troughing, vee and cantilever idlers

00 for flat idlers and brackets

Number of rollers followed by hanger code for garlands (see Table 6)

Roller mounting code (see Table 7)

Coating code (see Table 8) followed by RAL colour code

AAA - B - 1111 / 22 / C / DD.3333

EXAMPLE:Carrying troughing idler, belt width 650 mm, rollers angle 20°, rollermounting double flat, hot dip galvanised: CT - S - 650 /20 / A /HG

Idlers


27

TCT

TCF

TRV

TRF

IT

IG

CCT

CCV

Training carrying troughing

Training carrying flat

Training return "Vee"

Training return flat

Impact troughing

Impact garland

Centring carrying troughing

Centring carrying "Vee"

DESCRIPTIONCODE

T R A I N I N G S E T S

I M P A C T S E T S

C E N T R I N G S E T S

SRV

SRF

SRB

SRG

Self-cleaning return "Vee"

Self-cleaning return flat

Self-cleaning return bracket

Self-cleaning return garland

DESCRIPTIONCODE

S E L F C L E A N I N G S E T S

TABLE 5: Frame design codes

T

S

Tube frame design

Section frame design

DESCRIPTIONCODE

EasyRun® Ordering Codes


TABLE 6: Garland hanger codes

H

O

P

C

B

Hook

Open link

Stirrup type

Chain

Brace

DESCRIPTIONCODE

TABLE 8: Coating codes

PP

AC

WD

SZ

SE

HG

Polyester powder

Anti-corrosive synthetic primer coat

Water diluted

Painting system: zinc-phosphate primer coat

Painting system: two-component epoxy primer coat + epoxy-polyurethane top coat

Hot dip galvanised

DESCRIPTIONCODE

TABLE 7: Roller mounting codes

A

B

C

D

E

F

G

H

I

J

K

L

M

Double flat

Internal double flat

Bush

Garland

External thread + nut

External thread

Internal thread

Single flat

Internal single flat

Plain

Plain reduced

Internal reduced plain

External reduced thread

DESCRIPTIONCODE

Ordering CodesIdlers


Drum style pulleysCan be used at any location. It consists of a rimshell, 2 end discs and 2 shaft locking assemblies.

Wing style pulleysCan be used as a tail pulley and on gravity take-upassemblies. Helps prevent material build up andbelt damage from transported materials. It consists offace bars, fins, gussets and locking assemblies.

Squirrel cage style pulleysCan be used in the same positions as wing pulleysfor particular applications where very wet materialsare conveyed and where the inner surface of thebelt gets very dirty.

Pulleys are the main elements providing the transmission of torque fromthe drive and ensuring that belts remain taught. They have different functionsin conveyors depending on their position in the conveyor layout (drive/head, return/tail, tension, snubbing, redirection):

" Head/Drive Pulley is located at the discharge terminus of the conveyor.It provides the driving force for the conveyor. In order to increasepulley life and traction it often has a larger diameter than other pulleysin the conveyor and is lagged.

" Return/Tail Pulley is located just before the loading point of theconveyor

" Take-Up Pulley provides gravity force adjustments to maintain thenecessary slack side belt tension

" Take-Up Bend Pulley is used to change belt direction on the slackside of the conveyor. In order to increase belt life it is often lagged.

" Snub Pulley tightens the belt giving more surface contact betweenthe belt and pulley surface and is located immediately behindthe drive pulley.

Pulley diameter has a significant influence on the required power of thedrive and service life of the belt. The pulley diameter is dependent onthe chosen type of belt and thus on the material to be transported (type,grain size), the capacity (amount of t/hour, conveying speed), workingenvironment, structural design of the conveyor.

Pulleys have three basic design styles depending on operating conditionsand their function in the conveyor system:

Pulleys


31

The following parameters are required for designing a pulley:

1) Width of conveyor belt

2) Quality of conveyor belt

3) Conveyed amount of material (type of material)

4) Conveying speed

5) Length of conveyor and degree of incline

6) Type of drive station (single pulley x two-pulley)

7) Number of drive units

8) Power of drive units, weight

9) Bearings of drive units – coupling with pulley

10) Start up – starting drive units

11) Means of clamping the belt

12) Pulley diameter, bearing pitch, required service life of bearings

13) Working environment

14) Type of pulley, location along conveyor belt


33

Selecting Rollers

400

500

650

800

1000

1200

1400

1600

1800

2000

Beltwidth

B

3.5

3.5

3.5

3.5

3.5

3.5

5.5

7.5

3.5

5.5

7.5

7.5

7.5

7.5

Max. belt speed

m/s

6204

6204

6204

6204

6204

6204

6305

6306

6204

6305

6306

6308

6308

6310

Bearings

108/63

108/63

108/63

108/63

133/89

133/89

159/89

159/89

133/89

159/89

159/89

194/108

194/108

245/133

63,76,89

63,76,89

63,76,89

89,108

108,133

133

133

133

133

133

133

159

159

194

108/76

108/76

108/76

108/76

133/89

133/89

--

--

--

--

--

--

--

--

400

500

650

800

1000

--

1200

--

--

1400

--

1600

1800

2000

Diameter (mm)

500

600

750

950

1150

1400

1400

1400

1600

1600

1600

--

--

--

250

315

380

--

600

670

670

670

750

750

750

900

1000

1150

160

200

250

315

380

465

465

465

530

530

530

600

670

750

Roller length (mm)

*) Carryng idler roller lengths only apply up to belt widths of 650 mm. Return idler roller lengths apply to belt widths greater than 800 mm.

*)


Conveyor Components

Documents

Transcript of Conveyor Components