TECHNICAL INSTRUCTION LKT 1520.540.002 1 29 Per-Erik ... · Document type Document number Page of...

Document type Document number Page of

TECHNICAL INSTRUCTION LKT 1520.540.002 1 29 Prepared by Replaces Project number Revision Date

Lennart Skogfält 27 2017-06-29 Approved by Title Lang Technical area

Per-Erik Jönsson Design of belt conveyor systems en M Status Subtitle Plant reference code /object

Approved

Dependence on/from other documents Replaced by

Supplier

Dependence on/from other documents Replaced by

Design, planning, purchasing, operation and maintenance, storage Keywords Supplier’s reference designation

Instruction, code of practice

Document history Revision Date Signature Comments

01 2005-11-29 LS Instruction reworked

02 2005-12-12 MLPRJO Instruction approved

03 2005-12-29 LS Bulk density adjusted

04 2006-01-09 LS Max. inclination of conveyor and bulk density deleted

05 2006-01-10 LS Inclination and bulk density reinserted, minor revisions

06 2006-01-13 MLPRJO Document layout and Table of content revised

07 2006-01-16 MLPRJO Corrected to correspond with Swedish version; max inclination

08 2006-04-19 MLPRJO Caption “Lateral sealing system” inserted above text

09 2006-05-05 LS Safety distance between idlers and skirt plate/feed hopper added

10 2006-05-15 LS Emergency stop device and system for monitoring reworked

11 2006-05-18 LS Revision of text under caption Emergency stop devices

12 2006-06-07 LS Correction of maximum inclination in Table of Material data

13 2006-11-01 MLPRJO Recommendation of crowning inserted on page 17 Pulley shell

14 2007-08-24 MLPRJO Clarification on page 4 of demands for inclined conveyors

15 2008-04-03 KLKEHU Synchronisation between Swedish and English version

16 2008-09-23 KLKEHU Revision page 19 sentence about probe weight inserted

17 2009-04-07 MLPRJO Revision of ”Crowning of pulley shell” page. 17

18 2010-06-15 MLPRJO Caption “Safety functions” inserted, rec. on selection of sensors removed

19 2010-07-07 MLPRJO Synchronization of content in the Swedish and English version

20 2011-01-26 MLPRJO Revision under Safety function, Emergency…, System for …

21 2013-04-09 KLKEHU New logotype

22 2013-06-20 MLPRJO Caption “Guards” inserted. Additions under “LKAB’s requirements”,

“Clearance in conveyor walkways” and “Emergency stop devices for pull-

cord”. Revision of references.

23 2014-02-26 MLCHGA Additions under “System for monitoring of belt conveyor” page 25-26

24 2014-07-02 MLPRJO Ranges for dimension B and D on page 6 added.

25 2015-01-09 MLPRJO Clarification under “Carrying idlers, loading and return idlers”

26 2015-10-29 MLPRJO New caption “Misalignment”. Incorporate SveMin's demands in “Guards”

27 2017-06-29 PEJCO New caption “Selection of guards” inserted. Fire safety clarified.

Revision of references. Minor editorial changes

Translation This document is a translation from Swedish of LKAB Technical Instruction LKT 1520.540.001. In

the event of disagreement concerning the interpretation and content of this text, the Swedish version

shall have priority.

Latest revision: The latest revision of this instruction can be obtained from e-mail address:

[email protected] or [email protected]





Approved

Table of contents

BELT CONVEYORS ....................................................................................................................................................... 3 REFERENCES ................................................................................................................................................................... 3 BACKGROUND AND PURPOSE .......................................................................................................................................... 4 DIMENSIONING ................................................................................................................................................................ 4 LKAB’S REQUIREMENTS ................................................................................................................................................. 4 MATERIAL DATA ............................................................................................................................................................. 5 BELT SPEED ..................................................................................................................................................................... 5 CONVEYOR FRAME .......................................................................................................................................................... 6

CLEARANCE IN CONVEYOR GALLERIES .............................................................................................................. 6 BACKGROUND AND PURPOSE .......................................................................................................................................... 6 REQUIREMENTS ............................................................................................................................................................... 6 SAFETY DISTANCE ........................................................................................................................................................... 7

GUARDS ........................................................................................................................................................................... 8 SELECTION OF GUARDS ................................................................................................................................................... 9 DESIGN OF GUARDS ......................................................................................................................................................... 9 PROTECTION IN CONNECTION WITH WALKWAYS ............................................................................................................. 9

CONVEYOR BELTS ..................................................................................................................................................... 11 REFERENCES ................................................................................................................................................................. 11 REQUIREMENTS ............................................................................................................................................................. 11

Fire safety for conveyor belts within LKAB’s plants in Sweden and Norway .......................................................... 11 Belt designation ........................................................................................................................................................ 11

QUALITY REQUIREMENTS .............................................................................................................................................. 12 Thickness .................................................................................................................................................................. 12 Width ........................................................................................................................................................................ 13 Length ....................................................................................................................................................................... 13 Straightness .............................................................................................................................................................. 13 Adhesion ................................................................................................................................................................... 13 Cover layers ............................................................................................................................................................. 13 Marking .................................................................................................................................................................... 14 Selection table .......................................................................................................................................................... 14 Lateral sealing system .............................................................................................................................................. 14

CARRYING IDLER, LOADING AND RETURN IDLER ........................................................................................... 15 REFERENCES ................................................................................................................................................................. 15 REQUIREMENTS ............................................................................................................................................................. 15

PULLEY .......................................................................................................................................................................... 16 CENTRE DISTANCE BETWEEN BEARING HOUSINGS ......................................................................................................... 16 PULLEY SHELL............................................................................................................................................................... 17 CROWNING OF PULLEY SHELL ....................................................................................................................................... 17 BELT MISALIGNMENT .................................................................................................................................................... 17

SCREW JOINTS IN PULLEY END PLATES ........................................................................................................... 18 GENERAL ...................................................................................................................................................................... 18 TIGHTENING .................................................................................................................................................................. 18 TORQUE ........................................................................................................................................................................ 18 TIGHTENING SEQUENCE ................................................................................................................................................. 19

End plate with a locking assembly type Ringfeder RfN 7012 ................................................................................... 19 End plate with clamp casing ..................................................................................................................................... 20

DRAWINGS OF PULLEYS, AXLES AND BEARINGS ............................................................................................................ 21 CLAMP HUBS AND CLAMP .............................................................................................................................................. 21

REQUIREMENTS FOR BEARING SPECIFICATIONS........................................................................................... 22 REFERENCES ................................................................................................................................................................. 22 BACKGROUND AND PURPOSE ........................................................................................................................................ 22 REQUIREMENTS ............................................................................................................................................................. 22





Approved

Suppliers ................................................................................................................................................................... 22 Assembly ................................................................................................................................................................... 22 Vibration monitoring ................................................................................................................................................ 22

SAFETY FUNCTIONS .................................................................................................................................................. 23 EMERGENCY STOP DEVICES FOR PULL-CORD ................................................................................................ 23

REFERENCES ................................................................................................................................................................. 23 REQUIREMENTS ............................................................................................................................................................. 24 ASSEMBLY AND INSTALLATION OF EMERGENCY STOP DEVICES ..................................................................................... 24

SYSTEM FOR MONITORING OF BELT CONVEYOR ........................................................................................... 25 SYSTEM FOR MONITORING OF BELT SPEED, BREAKAGE, SLIPPAGE AND TENSIONING ..................................................... 25 SYSTEM FOR BELT ALIGNMENT MONITORING ................................................................................................................ 25 ADVANCED SYSTEMS FOR INCREASED BELT MONITORING ............................................................................................. 26 SYSTEM FOR MONITORING OF LEVEL IN CHUTE ............................................................................................................. 26 SYSTEM FOR POSITION MONITORING ............................................................................................................................. 26

GEAR BOXES ............................................................................................................................................................... 27 DRAWING INDEX OF ALL BELT CONVEYOR COMPONENTS ......................................................................... 28 SUGGESTIONS FOR IMPROVEMENTS .................................................................................................................. 29

Belt conveyors References EN 620 Continuous handling equipment and systems - Safety and EMC requirements for

fixed belt conveyors for bulk materials

EN 620 does not meet all of LKAB’s safety requirements for fixed conveyor systems. LKAB therefore

place higher demands on conveyors in its plants than EN 620 specifies. If the requirements in the

directives or harmonised standards exceed the requirements in this instruction, then the directives always

have precedence over the contents of LKAB’s instructions.

ISO 1819 Continuous mechanical handling equipment - Safety code - General rules

SS 2888 Continuous mechanical handling equipment - Belt conveyors - Idlers

EN 954-1 Safety of machinery - Safety-related parts of control systems - Part 1: General

principles for design. Replaced by EN ISO 13849-1. If the requirements of a type C

standard refer to a dated standard, only the requirements of the edition cited apply.

EN-ISO 13849-1 Safety of machinery - Safety-related parts of control systems - Part 1: General

principles for design.

EN-ISO 13849-2 Safety of machinery - Safety-related parts of control systems - Part 2: Validation

EN ISO 13850 Safety of machinery - Emergency stop - Principles for design

EN 62061 Safety of machinery - Functional safety of safety-related electrical, electronic and

programmable electronic control systems

EN ISO 13857 Safety of machinery - Safety distances to prevent hazard zones being reached by

upper and lower limbs

EN ISO 14120 Safety of machinery - Guards - General requirements for the design and construction

of fixed and movable guards

EN ISO 14122-1 Safety of machinery - Permanent means of access to machinery - Part 1: Choice of

fixed means of access between two levels

EN ISO 14122-2 Safety of machinery - Permanent means of access to machinery - Part 2: Working

platforms and walkways





Approved

EN ISO 14122-3 Safety of machinery - Permanent means of access to machinery - Part 3: Stairs,

stepladders and guard-rails

EN ISO 14122-4 Safety of machinery - Permanent means of access to machinery - Part 4: Fixed

ladders

EN 60034-1 Rotating electrical machines - Part 1: Rating and performance

SveMin SveMin’s instruction for vehicles, machinery and technical equipment

LKT 1520.540.013 Calculations - Belt Conveyors (Only in Swedish)

Background and purpose

LKAB strives to follow international standards as much as possible and in our Technical instructions,

called LKTs, the company’s specific requirements and interpretations of standards are precisely

defined. The instructions also express the company’s experience as well as giving information on

LKAB’s choice of alternative solutions within standards.

LKAB can also state requirements that are higher than those found in standards. By following this

instruction, LKAB’s requirements are fulfilled.

LKAB has a long and sound experience of transporting material on conveyor belts, which has led

LKAB to develop this instruction for how conveyor systems should be built in order to obtain fully

acceptable quality and function in a plant.

Dimensioning

The supplier is responsible for dimensioning of belt conveyors. LKAB has developed

recommendations for dimensioning of belt conveyors, instruction LKT 1520.540.013 "Conveyor

Instruction - Calculations".

LKAB’s requirements

LKAB's requirement is that the safety of belt conveyors must meet the level of protection that is

expressed in standard EN 620 and this technical instruction. The requirements of EN 620 and this

instruction are also applicable for use underground at LKAB. For potentially explosive atmospheres,

additional requirements apply. Note that conveyors within LKAB can operate at much lower or higher

ambient temperature than the standard covers and the conveyors therefore must be adapted to current

temperature ranges.

The need for safety equipment shall be assessed case by case, after risk assessment, if the inclination

and the amount of goods being transported can pose a danger of personal injury or plant damages, if

the driving force ceases to function.

In order to prevent conveyor belts from rolling forwards or backwards all inclined conveyors, in

which the transported load through its movement or potential energy could cause an increase in speed,

shall have a safety mechanism which is triggered if the driving force ceases to function. LKAB

requires that the safety mechanism must include a backstop and disc brake.

Dimensioning of the safety mechanism is performed by the conveyor supplier.

For safety functions on a belt conveyor we refer to chapter "Safety Functions"





Approved

Conveyor systems shall be built of objects with set standard dimensions for bearing spacing, axles,

rollers, width across flats, etc. so that interchangeability is achieved regardless of manufacturer or

supplier and so that conveyor-related spare parts inventories can be minimised.

Material data

Data are indications only and shall be verified for each and every project.

Material Material

size

Moisture

content %

Volume weight

tonne/m³

Material

Type

Max. inclination

in degrees

Iron ore -1000 2,1 2 18

Crushed iron ore - 400 2,2 2 18




Waste rock - 1000 1,6 2 18

Crushed waste rock - 400 1,6 2 18



Ore concentrate 0-2 2,8 1 20





Ore concentrate > 10 3,0 3 8

Pellets 2,1 1 18

Belt speed

In order to limit dusting and spillage in the plant, the maximum recommended belt speed is 2,0 m/s.





Approved

Conveyor frame

The principal dimensions for idler brackets and the conveyor frame’s cross section are given in the

figure and table below. The conveyor frame consists of a U-beam with the flange facing out

Beam web inwards

Belt width 650 800 1000 1200 1400 1600 1800 2000

A 950 1150 1350 1600 1800 2000 2200 2400

B * 600 600 600 700 700 700 800 800

The dimension D is dependent on the belt type and / or on if a belt scale is close to the pulley. If D > 0

the idler brackets closest to the pulley preferably are angled up so that the belt gets in contact with

the carrying idlers and reduces the belts swaying movement up and down.

0 ≤ D ≤ Half the trough depth

V = Angle 30° or 45°

Reference: ISO 1819 and SS 2888

"x" = the space between the centre roller and the side rollers shall not exceed 10 mm.

*) dimension B is dependent on required angle of wrap and may differ from the tabulated value.

Clearance in conveyor galleries Background and purpose

LKAB has built up an expertise on enclosed conveyor galleries for providing service areas with good

working conditions and security, based on long and solid experience. The purpose of this instruction

is thus to ensure that LKAB obtains space that is adapted to the company’s conveyor instruction for

conveyor frames.

Requirements

LKAB has greater requirements for spaces around conveyors than the European standard EN 620

specifies and refers to LKAB’s type drawing which specifies service spaces around built-in conveyors

as well as states inclinations that make cleaning and flushing possible in the conveyor walkways. It

is also necessary to take into account the space required for splicing and repair of conveyor belts as

the work may need to be carried out even when the adjacent conveyors are in operation. All walkways,

EDGE OF PULLEY





Approved

stairs, stepladders or platforms shall at least have a clear width of 800 mm and the clear height shall

be at least 2100 mm. Only in exceptional cases, after risk assessment, the width may be reduced to

600 mm if the walkway is used only occasionally and the reduction is limited to a short distance, for

example at a column. For guards in connection with walkways for example in passages where the

walkways width is perceived as narrow/cramped, we refer to chapter "Guards".

The harmonised European standards EN ISO 14122-1 to -4 state requirements for access to machines

(stairways, ramps, walkways, working platforms, guard-rails, etc.) that fulfil the Machine Directive’s

safety requirements. If the requirements in the directive or harmonised standards exceed the

requirements in this instruction, then the directive always has precedence over the contents of

LKAB’s type drawings.

The minimum dimension of 2100 applies to service areas on both sides of the conveyor.

Belt width

B mm

Total conveyor frame width

b mm

Walkway minimum

a mm

Other service area

c mm

650 1050 800 800

800 1250 800 800

1000 1450 800 800

1200 1700 800 800

1400 1900 1000 800

1600 2150 1000 800

1800 2400 1000 800

2000 2650 1000 800

If there are walkways on both sides, replace dimension c with dimension a.

Conveyor gallery, lengthwise Floor incline also here =1:40 ( 1,5°), in the case of

“horizontal” conveyors.

The minimum dimension of 2100 applies to all service areas.

Safety distance

Distance between idler and fixed parts of skirt plate/feed hopper must be larger than 150 mm. See

above.

FEED HOPPER

α





Approved

Guards Mechanical hazards at nip points shall be safeguarded in the manner specified in the harmonized

standard type C, EN 620. For risks in contact points between belt and idlers, the standard already has

identified and marked the potentially dangerous nip points on conveyors. See the picture below. Note

that not all contact points between belt and idler are considered as dangerous nip points. A dangerous

nip point is defined by that the belt cannot lift from the idlers or pulleys to produce a clearance of at

least 50mm where the belt touches the periphery of the idlers.

The belt’s lifting can be hindered by fixed parts, such as cross bars, skirt plates, loading and unloading

areas, convex curve and at transition between flat and troughed belt, where the belt is reversed or

deflected and other places where the pressure between belt and idlers becomes high, that is, affected

by other than the belt and the conveyed material.

Key

1 Feed hopper 9 Tail pulley

2 Idlers at convex curve (brow) position 10 Tripper discharge pulley

3 Direction of belt travel 11 Take up pulley

4 Transition idler 12 Gravity take-up weight

5 Head pulley 13 Bend pulley

6 Snub pulley 14 Typical tripper

7 Scraper 15 Reversible belt

8 Drive pulley 16 Nip point

The potentially dangerous nip points identified and marked (16) above shall be protected if they are

normally accessible to personnel.





Approved

Selection of guards

It is important that the selection of guards and design of guards is preceded by risk assessments so

that the guard itself does not cause any additional risk. In order to maintain the respect for guards,

they must be perceived as justified.

In the standard EN 620 four types of guards are stated that can be used to prevent risk against

entanglement, drawing-in and trapping in potentially dangerous nip points; fixed enclosing guards,

fixed distance guards, interlocking guards or volume-filling guards at the nip point, so called “nip

guards”. Enclosing guards prevents access to the hazard zone from all sides, while distance guards

prevent access to the hazard zone from at least one direction. Interlocking guards are guards with

interlocking device that together with the control system prevents the hazard zone from being

accessible when the conveyor is in motion if the guard is removed or opened. Volume-filling guards,

so called “nip guards”, should fill the area at the point of contact between conveyor belt and idler or

pulley and thereby reduce the risk of drawing-in at the nip point. However, according to the

requirements of the standard EN 620, the gap between the volume-filling guard and the moving belt

must never exceed 5 mm to fulfil as a guard against drawing-in. The requirement cannot be met for

example for conveyors with troughed belt profile. Furthermore, the guard can create new risks, such

as accumulation of dust and spillage from transported material in the gap. If the risk assessment shows

that the nip points must be guarded, LKAB's recommendation is to use distance guards or enclosing

guards, as these are not limited to belt profile, type of conveyor belt, conveyor belt movement or

transported material.

Design of guards

It is important that guards are designed to enable routine adjustments, lubrication and maintenance to

be carried out without opening or removing the guards. The guards shall be designed to permit visual

inspection during operation. Furthermore, the design of the guards should enable spillage to be

cleared without removal of the guards, for instance with a gap or opening that meets the requirements

of EN 620. Guards should be very quick to disassemble and re-assemble, easy to handle, modularly

designed and only in exceptional cases designed for a specific placement.

Where a conveyor passes above working or traffic areas, suitable protection shall be provided against

falling parts of machinery, such as return idlers (with e.g. catching trough) or belt failure (with e.g.

protection plate, wire mesh, etc.).

Protection in connection with walkways

Walkway in angle to the belt conveyor

Belt conveyors should be provided with guards in the area where the walkway connects to a walkway

along the conveyor or where a stair or ladder leads up/down towards the conveyor.

Walkway along the conveyor

Determine which walkways that needs to be used during transfers in the plant. Make risk assessments

on where guards need to be mounted along these walkways. Guards must not lead to new risks.

Remaining possible walkways are provided with warning sign; EJ GÅNGVÄG [=NOT WALKWAY.

Use Swedish designation, English translation is for your information only].





Approved

Primarily, the conditions along the walkway should be eliminated that leads to increased risks to

access dangerous nip points, because one can stumble, fall, slip or get hooked/ trapped in protruding

parts. These may be, for example:

• differences in levels or upstanding objects in the walkways floor

• stairs or ladders in the walkway

• walkways width is perceived as narrow/cramped

• protruding parts in the walkway

• spillage makes the walkway slippery or uneven

• the belt conveyors inclination

At inclined belt conveyors, a handrail may reduce risks by providing support for walking downwards

and upwards as well as directing pedestrian traffic to the side of the walkway where the handrail is

mounted.

Workplace adjacent to belt conveyor

Make risk assessments if guards need to be installed on belt conveyors at workplaces adjacent to

conveyors in operation. By workplaces is meant e.g. inspection panels in feed hoppers, sampling

locations, vulcanization locations and the like.





Approved

Conveyor belts

References

DIN 22109 -1 to - 2 Conveyor belts with textile plies for coal mining; - Part 1: Monoply belts for

underground applications. Dimensions, requirements - Part 2: Rubber belts

with two plies for underground applications. Dimensions, requirements

DIN 22109 -4 Conveyor belts with textile plies for coal mining; - Part 4: Rubber belts with

two plies for above ground applications. Dimensions, requirements

DIN 22129-1 to - 4 Steel cord conveyor belts for underground coal mining; Part 1:

Dimensions, requirements – Part 2: Marking – Part 3: Testing – Part 4: Belt

joints. Dimensions, requirements

DIN 22118 Conveyor belts with textile plies for use in coal mining; fire testing

SMS 2329 Conveyor belts with textile carcass. Dimensions and marking

Requirements

Fire safety for conveyor belts within LKAB’s plants in Sweden and Norway

According to LKAB's requirements for fire safety for conveyor belts in LKAB's plants, all conveyor

belts in underground installations, in buildings and in conveyor galleries must always be self-

extinguishing quality (VLS). Exceptions to the requirement must be approved by LKAB's Fire Safety

Function. The Fire Safety Function also states when sprinklers are required for conveyors.

Belt designation

Belt designations that shall be used in constructing conveyor belts

DIN 22109 is the entrance standard for self-extinguishing conveyor belts with textile

reinforcement

DIN 22109-1 See references above.



DIN 22129-1 to -4 See references above.

This system states the belt’s total tensile strength, lengthwise.





Approved

Example of a belt designation

800 EP 630/4 6/2 N ID no.

Belt width in mm

Reinforcing material

Ultimate tensile strength in N/mm belt width

Upper/lower cover layer thickness in mm

Cover layer’s quality

Object marking for traceability

Quality requirements

Thickness

See nominal belt thicknesses in the table on page 14. Variation in belt thickness is allowed within the

limits specified in SMS 2329.

Upper cover layer T1

T

Textile layer Lower cover layer T2

The difference in belt thickness for nominal belt thicknesses up to 10 mm can be a maximum of 1 mm

and for belt thicknesses over 10 mm it can be a maximum of 10% of the nominal thickness.

The thickness of the cover layers may deviate from that in the order specification, as long the lower

deviation does not exceed;

- 0.2 mm for base dimensions up to and including 4 mm

- 5 % of the base dimension for base dimensions over 4 mm

Deviations from the upper measure have not been determined.

Thickness is measured according to SMS 2468.





Approved

Width

According to SMS 2329.

Base dimension=B 650 800 1000 1200 1400 1600 1800 2000

Deviation ± 6.5 ± 8 ± 10 ± 12 ± 14 ± 16 ± 18 ± 20

Length

According to SMS 2329.

The belt can be endless or in an open position. There should be no tension on the belt

when it is measured. Endless belts are measured on the belt’s inside.

Endless: Ordered length ± 0.5 %

Open length: Ordered length + 2 -0.5%

Straightness

According to DIN 22102.

The belt shall be straight along its whole length. The maximum sideways deviation is

given in the table below, the values of which are taken from problem-free conveyors

running unloaded.

Belt width, mm

Max allowable

sideways deviation

< 800 ± 40 mm

800-1400 ± 5%

> 1400 ± 75 mm

Adhesion

According to ISO 252, ISO/R 36.

Minimum adhesion

– between cords: 3.5 N/mm

– between cover layers and cords:

2.4 N/mm for cover layers 0.8-1.5 mm

3.0 N/mm for cover layers > 1.5 mm

Maximum adhesion: 9.0 N/mm

Cover layers

Quality V according to: DIN 22102

Tensile strength: min 20 N/mm2

Ductility: min 400 %

Abrasion: max 200 mm3

Self-extinguishing type V, fire resistance test according to DIN 22118





Approved

Marking

Belts are marked according to SMS 2329 so that the type of reinforcement, tensile strength, number

of plies, cover layers’ thickness and quality are described. Deviations allowed only by special

agreement.

Selection table

Belt type

Belt width E400/1

8 + 3

EP400/2

5/1.5

EP630/4

6/2

EP800/5

6/2

EP1250/5

6/2

EP1250/5

8/2

650 2 1* 1*

800 2* 1* 1 1*

1000 2* 1* 1* 1*

1200 1* 1* 1* 1*

1400 1* 1*

1600 1* 1* 1*

1800 1

2000 1*

Nominal belt

thickness

12.5 9.9 12.4 14.0 15.0 17.0

1 = Preferred standard (first choice)

2 = Alternative to EP 400/2 - 5/1,5

* = Stock goods in Kiruna or Malmberget

NOTE: In need of belts that are not stock item at LKAB belts should, if possible, be selected from

the suppliers' stock range or standard assortment.

Special orders must be avoided.

Lateral sealing system

Lateral sealing system shall be of self-extinguishing V quality, NBR





Approved

Carrying idler, loading and return idler References

Selected from Impact Rings type "B" according to SS ISO 4123 “Belt conveyors – Impact rings for

carrying idlers and discs for return idlers – Main dimensions”

Requirements

This instruction shall be applied when purchasing conveyors or replacement idlers.

Idlers coated with rubber or fitted with impact rings must have rubber of the same quality as the

conveyor belt, self-extinguishing V quality, NBR.

Bearings for axles Ø 30: Deep-groove ball bearings with an inner and outer contact seal, according

to LKAB type drawings. (Applies to carrying idlers).

Outside diameter Ø 159 mm of carrying idlers and impact rings on the return idlers. Details according

to the LKAB type drawings. See chapter "Drawing index of all belt conveyor components."

Figure: Dimensions of carrying and loading idler as well as return idler. (Not to scale).

Note: x) Idler Ø 108 mm used only exceptionally, for reasons of space.

xx) Axle Ø 30 mm and A/F 22 mm are used for new investments. In existing plants the

standardized axle is to be introduced in conjunction with major repairs or rebuilds.

(A/F=across the flats)

z) 76.1 mm applies to belt width ≤ 1400 mm

zz) 108 mm applies to belt width > 1400 mm

Recommendation: The conveyor belt sag between the return rollers may not exceed 1% of the

distance between the rollers.





Approved

Pulley Centre distance between bearing housings

This specification describes the relationship between: Belt width, pulley length and carrying idler

distance.

Belt width 650 800 1000 1200 1400 1600 1800 2000

Pulley

length

750 950 1150 1400 1600 1800 2000 2200 Bearing housing

Axle d1 Bearing centre distance c-c

55 1000 1200 1400 1650 1850 2050 SNH 512

60 1000 1200 1400 1650 1850 2050 2250 SNH 513

70 1000 1200 1400 1650 1850 2050 2250 2450 SNH 516

90 1000 1200 1400 1650 1850 2050 2250 2450 SNH 520

110 1000 1200 1400 1650 1850 2050 2250 2450 SNH 524

125 1050 1250 1450 1700 1900 2100 2300 2500 SNH 528

140 1050 1250 1450 1700 1900 2100 2300 2500 SNH 532

160 1100 1300 1500 1750 1950 2150 2350 2250 SD 3136

180 1150 1350 1550 1800 2000 2200 2400 2600 SD 3140

200 1150 1350 1550 1800 2000 2200 2400 2600 SD 3144

220 1150 1350 1550 1800 2000 2200 2400 2600 SD 3148

240 1150 1350 1550 1800 2000 2200 2400 2600 SD 3152

260 1150 1350 1550 1800 2000 2200 2400 2600 SD 3156

280 1250 1450 1650 1900 2100 2300 2500 2700 SD 3160

300 1300 1500 1700 1950 2150 2350 2550 2750 SD 3164





Approved

Pulley shell

Pulley diameter Pulley drawing Kiruna Pulley drawing Malmberget

315 227794 2-4744-97

500 227795 2-4744-98

630 227796 2-4744-99

800 227797 2-4744-103

1000 227798 2-4744-104

1250 227799 2-4744-105

Crowning of pulley shell

To reduce the risk of misalignment of the belt the manufacturers of belts recommend crowning of the

pulley shell. If the crowning is too large it becomes ineffective. To get a crowning to work satisfactory

the belt must be in close contact with the shell uniformly over the pulley. It is very important that a

crowning of a pulley is according to the formula below. For a correct crowning of the pulley the

diameter of the end of the shell is reduced with 1/150 of the diameter of the mid of pulley.

If several pulleys are placed close to each other, only one pulley should be crowned or half the

crowning should be made on two adjacent drums.

Belt misalignment

To reduce the conveyor belt misalignment, it is important to control the flow of material so that the

loading point on the belt is as centred as possible. If the carrying idler sets are tilted forward 1.5° - 3°

the belt is centred towards the middle and the misalignment decreases. The option rotary stabilisation

with return idlers and / or carrying idler sets are superior to crowning. Friction coating increases the

steering effect. The conveyor belt wanders in the direction where the belt first hits the idler/pulley.

Keep in mind that rubber is a "living" material and the conveyor belt may be allowed to move

sideways ± 5% of the belt width. Ensure that there is sufficient lateral movement range on the return

idlers and adjustability for rotary stabilisation.

Suitably, the frame is provided with measurement points to base the alignment of the drive and tail

pulley in 90° angle relative to the frame. A skewed pulley wears the pulley shell, because the belt is

forced to move back and forth over the shell.





Approved

Screw joints in pulley end plates

General

The prerequisite for a safe screw joint is that the screws are mounted with the right torque. An

incorrectly tightened screw joint where the end plate meets the axle can cause breakdowns, as

experience has shown.

Tightening

Tightening with percussive tools does not give sufficiently accurate tightening, even if the tool can

be set to the desired torque. Re-tightening must therefore be performed using a releasing-type torque

wrench set to the torque applicable to the screw dimension and strength class in Table 1.

Torque

Torque in Nm (kpm). These values apply to screw joints with lightly oiled threads and contact

surfaces. NOTE! Do not use Molybdenum sulphite (MoS2).

Table 1

Threads

Strength class 12.9

Torque

Nm kpm

M 12 122.6 (12.6)

M 14 186.3 (18.6)

M 16 289.3 (28.9)

M 18 397.2 (39.7)

M 20 568.8 (56.8)

M 24 980.7 (98.7)





Approved

Tightening sequence

The screw joint is tightened crosswise according to the sequence in the figure below.

End plate with a locking assembly type Ringfeder RfN 7012

1. The outer flange joint is tightened first with torque according to settings in Table 1.

2. The clamp’s screws are first tightened by hand until there is no gap. Accuracy in this step is

crucial for centring.

3. The screws are then tightened to about half of the specified torque, and thereafter to the torque

applicable to the torque appropriate to the screw dimension and strength class 12.9.

4. A check of all the screws should be done crosswise, according to Figure 1.

Hardened steel washer of type BRB, BRFB

Screw strength class 12.9





Approved

End plate with clamp casing

The screw joint is tightened according to the torque in Table 1, the outer flange joint first. The

accumulation space “A” can be used as a check. The clamp casing is tightened until the gap is closed,

and then a further distance as specified in Table 2. During assembly, take care that the clamp casing

slides inwards towards the axle so that the end plate is not forced or bent outwards.

Table 2

Axle diameter D Accumulation space A

x (55) 0.6-0.8

x (60) 0.7-0.9

70 0.8-1.0

90 1.0-1.3

110 1.2-1.6

125 1.4-1.8

x non-standard

Hardened steel washer of type BRB, BRFB

Screw strength class 12.9





Approved

Drawings of pulleys, axles and bearings

Pulley

diameter

Pulley drawing no End plate drawings for

clamp hubs

End plate drawings for

Rfn 7012

Kiruna Malmberget Kiruna Malmberget Kiruna Malmberget

315 227794 2-4744-97 225169 2-4744-56

500 227795 2-4744-98 225168 3-4744-57 332290 3-4744-108

630 227796 2-4744-99 225168 2-4744-57 332290 3-4744-108

800 227797 2-4744-103 151644 1-4744-101 146741 1-4744-102

1000 227798 2-4744-104 151644 1-4744-101 146741 1-4744-102

1250 227799 2-4744-105 151644 1-4744-101 146741 1-4744-102

Clamp hubs and clamp

Axel d1

Axel d2

Clamp hub Drawing No

Clamp Rfn 7012 Kiruna Malmberget

50 70 2-4744-58

55 70 225170/1

60 70 225170/2

70 70 225170/3

90 90 225170/4

110 110 225170/5

125 125 225170/6 2-4744-58

140 140 x 190

160 160 x 210

180 180 x 235

200 200 x 260

220 220 x 285

240 240 x 305

260 260 x 325

280 280 x 355

300 300 x 375

320 320 x 405

340 340 x 425





Approved

Requirements for bearing specifications References

EN 60034-1 Rotating electrical machines. Part 1: Rating and performance

Background and purpose

The purpose of this instruction is to have ball bearings and roller bearings delivered with the following

specifications: assembly instructions, data for vibration monitoring, if service is available from the

supplier (bearing service is principally used for larger bearings, such as those used in drive axles or

mill axles, for example).

Requirements

Suppliers

Suppliers shall deliver specifications, current data for vibration measurement, and necessary service

for bearings. These are best entered on Object card LKT 1500.150.002.

Assembly

Assembly information required to achieve a completely satisfactory result, such as recommended

bearing gaps, pressing onto bushing, service intervals, required tools, etc.

Vibration monitoring

When monitoring vibrations, certain data is required so that satisfactory measurements can be carried

out, such as frequencies of the inner ring and outer ring, number of rollers and bearing casings. This

data is required for ball bearings and roller bearings from the manufacturer so that satisfactory

vibration measurements can be carried out.





Approved

Safety functions

Documented risk assessments of each conveyor belts design, operation and use shall be conducted to

determine the necessary safety functions that have been identified and how they are to be executed.

Identified safety functions' demands on performance level, PL, affects the selection of components

(e.g. sensors) as well as design of and integration into control systems. (See EN ISO 13849-1).

Note: Risk assessments determines if the functions are safety functions or for monitoring.

The harmonized standard, type C, EN 620 defines how the safety functions for monitoring and control

of conveyor belts are to be performed: “The control system and control equipment shall be designed

using proven techniques and shall use proven components (see EN 60204-1:1997, 9.4). The safety

related parts of the control system shall be designed in accordance with the requirements of at least

EN 954-1 Category 1 (see EN 954-1:1996, 6.2.2). Where programmable electronic equipment, or

electronic devices including electronic sub-assemblies are used for safety related purposes, they shall

be in accordance with the requirements of at least EN 954-1 Category 2 (see EN 954-1:1996, 6.2.3).”

NOTE: EN 954-1 has been replaced by EN ISO 13849-1 and Category has been replaced by

Performance level, PL

Electrical safety functions are defined by standard EN 620 and even by suppliers of conveyors and

some examples are listed in this non-exhaustive list below:

□ Pull-cord controlled emergency stop device for assembly along the conveyor belt on one or both

sides, possibly supplemented by a push button controlled emergency stop on an optional location.

□ Lockable safety switch located at the motors.

□ Speed controls in various designs. Non-contact sensors placed at one of the return rollers have

proven to have high availability.

□ Misalignment detection devices are used to warn, and stop the conveyor if the belt has deviated

sideways.

□ Rotating warning light and / or audible warning signals in connection with the start of the

conveyor where it is required.

□ Level sensors for detection of the level in e.g. discharge chutes and / or hoppers.

Emergency stop devices for pull-cord Emergency stop devices shall, in accordance with harmonized standard type C, EN 620, be reachable

at all control stations, working positions and at accessible parts of the machinery including loading

points, unloading points, walkways and transfer points. According to EN ISO 13850 the means to

reset the emergency stop device should be placed so that the entire pull-cord is visible from the

location of the resetting means.

References AFS 2008:3 Machinery [Swedish implementation of Machinery Directive 2006/42/EC]

AFS 2008:13 Signs and signals [Swedish implementation of Directive 92/58/EEC]

AFS 2006:4 Use of work equipment [Swedish implementation of Directive 2009/104/EC ”Use of

Work Equipment” (89/655/EEC codified)]

ASS 128 Conveyors – The National Board of Occupational Safety and Health Instruction No

128 1978 (Repealed 2007-07-01 but may be a guidance)





Approved

Requirements

The supplier shall deliver and mount pull-cord operated emergency stop devices according to EN ISO

13850.

The following emergency stop device systems have proven to function on LKAB’s conveyors:

Emergency stop devices of type Allen-Bradley with switch type Lifeline 4 including indicator

unit 3NC+1NO. E 37 752 04

Following cord tensioning system shall be used:

Conveyor length < 10 m LRTS 10m E 37 723 02

Conveyor length 10 – 20 m LRTS 20m E 37 723 06

Conveyor length 20 – 35 m LRTS 50m E 37 723 12

Stainless tensioning spring E 37 723 83

Sign with Swedish text E 38 025 90

One stainless tensioning spring is needed for each cable tensioning system.

Signs shall be mounted by switch and on each 5 meter on pull cord.

If pull cord gets longer than 35 meters an extra emergency stop device including cable

tensioning system and tensioning spring must be mounted on each 35 meters of the conveyor

length.

According to EN 620, the pull-cord operated emergency stop device shall be actuated by the

application of a horizontal force to the pull-cord of less than 125 N, at a point midway between two

support rings and perpendicular to the cord. The sideways cord movement (between the rest position

and the actuation position) shall be less than 300 mm.

According to EN ISO 13850 clause 4.4.5 and the Work Environment Authority's provision AFS

2008:13 the emergency stop devices, that are, push buttons (mushroom) and pull-cords must be red

and cords shall be fitted with signs or marker flags. Be aware that the symbol on the emergency stop

push button shall comply with EN ISO 13850 section 4.4.6, which means that either the push button

should have a symbol with a triangle pointing down, surrounded by a circle with an exclamation mark

in the middle or have no symbol at all. According to AFS 2008:13, Appendix 1, Chapter 5, the sign

to emergency stop is to be green. If the sign is part of an emergency stop cord, it must be red.

According to Work Environment Authority's provision AFS 2006:4 it is also appropriate that there is

a sign with the text “NÖDSTOPP”. [= “Emergency stop” in Swedish]

Assembly and installation of emergency stop devices

The assembly shall be in accordance with the supplier’s instructions. The National Board of

Occupational Safety and Health’s instruction “ASS 128” can also give guidance.

Extract from ASS 128 regarding emergency stop switches:

8.8 On locations by the conveyor where personnel normally are present or may be present; there

must be emergency stop devices in required extent.

8.9 When the emergency stop switches is activated the main power should be cut (either directly

or indirectly) immediately and with a lasting effect. The stop switch shall be forced into a

breaking mode and shall remain in that mode until reset manually. The conveyor must not

after that be started except from a therefore dedicated place. Emergency stop device shall

function independently of interlocking circuit between conveyors.





Approved

8.10 Emergency stop device shall, wherever appropriate, be activated by emergency stop in the

form of pull-cord, which shall be located so that it is easy to reach and to grasp. Emergency

stop device which is operated by pull-cord shall be designed so that it cuts off in whatever

direction the pull-cord is affected. Where appropriate, the pull-cord must be affected when a

person falls in towards the conveyor.

8.11 Emergency stop in the form of pull-cord shall at the appropriate distance (4-5 m) have durable

marker flags, …

System for monitoring of belt conveyor

The supplier shall deliver and assemble system for monitoring of belt conveyors according to

description below. The systems shall comply with the requirements in chapter "Safety functions".

The descriptions include solutions that have proven to function on LKAB’s conveyors.

For more demanding applications there are systems for advanced belt monitoring with higher

accuracy and increased monitoring.

System for monitoring of belt speed, breakage, slippage and tensioning

Sensors for monitoring of belt speed are, on LKAB conveyors, mounted at the drive, snub and tail

pulley.

The sensor is mounted to sense a metal flag mounted on the shafts of the pulleys. A mount is arranged

on the conveyor to allow an easy adjustment of the sensor. As a bracket for the sensor LKAB’s mount,

drawing No 352144, can be used. The cable of the sensor is connected to a junction box (E 1438481)

attached with wood-screws to a plastic oxylite plate dimension 200x150x20 mm. The plastic plate is

then attached with through screws to the conveyor frame.

The belt monitoring is conducted by sampling of signal to the control system from sensors on drive

pulley, compared with sensor on snub pulley and tail pulley. Warning and alarm conditions must be

determined for deviations between the signals from the sensors. The monitoring can be developed

and implemented in the control system to indicate belt breakage, slippage and tensioning problem.

System for belt alignment monitoring

Mechanical device for monitoring of belt alignment can be arranged according to LKAB drawing No

1041587.

Mount for belt alignment sensor on conveyor frame can be arranged according to LKAB drawing No

1041589.

The height of the mount is adjusted in a way that the conveyor belt, in the event of misalignment, hits

the roller of the belt alignment monitor just below the middle of the roller. The belt alignment monitor

is adjusted so that the sensor is actuated (1) when the alignment is correct and not actuated (0) when

there is misalignment.

The cable of the sensor is connected to a junction box (E 1438481) attached with wood-screws to a

plastic oxylite plate dimension 200x150x12 mm. The plastic plate is then attached with through

screws to the conveyor frame.





Approved

Advanced systems for increased belt monitoring

Advanced systems for increased belt monitoring by "on-line" scanning and image processing are not

part of LKAB's normal practice.

A rough risk and impact assessment for important belt conveyors without redundancy in the "red

production line" may through high levels of risk (R x K), indicate the need to implement advanced

systems for increased belt monitoring.

There are a number of suppliers of advanced systems for increased belt monitoring, suitable to

minimize the risk of production stop due belt damage. These advanced systems may, "on-line", for

example, indicate the following types of belt damage; belt cleavage, puncture damages, penetration,

surface defects, lamination problems, edge defects (rip-off detection), belt elongation, cords fracture

and belt breakage. Above examples of types of damage can be categorised into different level of

severity which may result in a warning and / or interlocking alarm. These alarms should be filtered

and suppressed so that the main control system / operator obtain relevant information for immediate

or planned actions.

LKAB's organisational plant owner evaluates the need and benefit of above advanced systems for

increased belt monitoring.

System for monitoring of level in chute

For monitoring of level in chute, a system of conductive type has proven to function on LKAB’s

conveyors.

The system consists of a probe, mounted in the chute in a way that allows easy adjustment of the

probe. As cable for the probe a steel wire with red plastic sheath, order No E 3772389.

The cable of the probe is fitted with a probe weight according to drawing 462576.

The cable of the probe is connected to a junction box (E 1438481) attached with wood-screws to a



System for position monitoring

For monitoring of position, sensors of inductive type have proven to function on LKAB’s equipment.

On objects where position is to be indicated a mount is arranged to allow easy adjustment of the

sensor and a reliable position indication. As a bracket for the sensor LKAB’s mount, drawing No

352144, can be used.

The cable of the sensor is connected to a junction box (E 1438481) attached with wood-screws to a







Approved

Gear boxes When conveyors are driven by belt driven transmissions, LKAB has the following preferences:

Preference 1

Gear boxes should preferably be selected from this series.

Type Old designation New designation Comment

Shaft mounted

Speed Reducers of

Sala type

BTV – 32 * J 32

BTV – 52 * J 52

TV – 72 * J 72

TV – 102 * J 72 5-138 kW

TV – 112 * J 100 Hollow shaft

TV – 122 * J 100 Parallel axles

TV – 152 * J 110

TV – 202 J 125

TV – 302 * J 125

TV – 402 * J 140

TV – 512 J 190

BTV – 53

TV – 103

TV – 203

Preference 2

Gears > 138 kW are selected from case to case at the design phase.

* Gear sizes TV-32 up to and including TV-402 are selected with conical mounting devices, so-

called tapered bush of type KIBO.

Note: When selecting gearboxes for new plants, full interchangeability shall prevail, regardless of the

manufacturer chosen.





Approved

Drawing index of all belt conveyor components LKAB Drawing No

Kiruna Malmberget

Assembly drawing 146740 1-4744-93

Pulley shell Dia.315 227794 2-4744-97

-"- 500 227795 2-4744-98

-"- 630 227796 2-4744-99

-"- 800 227797 2-4744-103

-"- 1000 227798 2-4744-104

-"- 1250 227799 2-4744-105

End plates for clamp hubs Dia. 315 225169 2-4744-56

-"- 500 225168 2-4744-57

-"- 630 225168 2-4744-57

-"- 800 151644 1-4744-101

-"- 1000 151644 1-4744-101

-"- 1250 151644 1-4744-101

End plates for Ringfeder Dia 500 332290 3-4744-108

-"- 630 332290 3-4744-108

-"- 800 146741 1-4744-102

-"- 1000 146741 1-4744-102

-"- 1250 146741 1-4744-102

Placement of plough scraper and guide brackets 234797 2-4744-128

Clamp hub 225170 2-4744-58

Bearing housing 146761 1-4744-92

Protective shield for bearing housing 328735 3-4744-106

Covers for locking assembly 436788 4-4744-107

Loading idler 446161 4-4744-23

Carrying idler 446160 4-4744-22

Conveyor Return idler 199347 1-4744-129

Return idler B=1600 245757 2-4744-130

Carrying idler 342173 3-4744-131

Loading idler 342174 3-4744-132

Counterweight 196837 1-4744-24

Attachment for Return idler Assembly 342286 3-4744-47

Details 342287 3-4744-48

Details 342288 3-4744-49

Safeguards, type drawing 451682 4-4744-112

Pull-core controlled emergency stop (assembly drawing) 320604 3-4744-127





Approved

LKAB Drawing No

Axles for drive and tail pulleys Kiruna Malmberget

Drive pulley

Axle diameter 70 329344 3-4744-66

60 342874 3-4744-122

55 342875 3-4744-123

90 329345 3-4744-67

110 329346 3-4744-68

110 342878 3-4744-124

125 TV 201, 202 329347 3-4744-69

125 TV 302 195766 1-4744-114

140 TV 302 195767 1-4744-113

140 TV 402 195761 1-4744-119

140 TV 402 195760 1-4744-120

160 TV 402 195762 1-4744-118

160 TV 402 195763 1-4744-117

160 TV 402 195764 1-4744-116

160 TV 402 195765 1-4744-115

Tail pulley (take-up pulley)

Axle diameter 55 329352 3-4744-79

60 342876 3-4744-125

70 342877 3-4744-126

90 329353 3-4744-80

110 329354 3-4744-81

125 329355 3-4744-82

140 329784 3-4744-83

160 329785 3-4744-84

180 329786 3-4744-85

220 329787 3-4744-86

Axle bushing, plastic, for carrying and return idlers 447376 4-4744-26

System for monitoring

Mount for sensor 352144

Belt alignment monitor, Assembly 1041587

Belt alignment monitor, Detail 1041588

Belt alignment monitor, Assembly instructions 1041589

Suggestions for improvements LKAB carries out continual improvements in accordance with the LKAB quality policy and this also

applies to instructions and codes of practice. Comments and suggested improvements are welcome at

the following e-mail address: [email protected]

The LKAB internal address in Outlook: SE SM Anvisningar LKT

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