AA SPEC 371001

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1

1 SCOPE

SCOPE

2

2 TECHNICAL

TECHNICAL REQUIREMEN

REQUIREMENTS

TS TO

TO BE

BE SPECIFIED

SPECIFIED BY

BY THE

THE PURCHASER

PURCHASER

2

3

3 DEFINITIONS

DEFINITIONS

2

4

4 REQUIREMENTS

REQUIREMENTS

3

4.1

4.1 D

D

ESIGN AND DIMENSIONSESIGN AND DIMENSIONS

3

4.2

4.2 H

H

UBS ANDUBS AND

E

NDND

D

ISKSISKS

5

4.3

4.3 S

S

HAFT AHAFT A TTACHMENTTTACHMENTSS

5

4.4

4.4 P

P

ULLEY SHELLSULLEY SHELLS

6

4.5

4.5 S

S

HAFTSHAFTS

6

4.6

4.6 B

B

EARINGS AND MOUNTINGSEARINGS AND MOUNTINGS

8

4.7

4.7 S

S

HELLHELL

C

ROWNINGROWNING

9

4.8

4.8 W

W

ELDINGELDING

9

4.9

4.9 S

S

TRESS RELIEVING AND NORMALISINGTRESS RELIEVING AND NORMALISING

10

4.10

4.10 L

L

AGGING AGGING

10

4.11

4.11 B

B

AL ALANCINGANCING

12

4.12

4.12 C

C

ORROSION PROTECTIONORROSION PROTECTION

12

5

5 QUAL

QUALITY

ITY ASSURANCE

ASSURANCE PROVISION

PROVISION

12

6

6 TEST

TEST AND

AND INSPECTION

INSPECTION METHODS

METHODS

12

6.1

6.1 N

N

ON DESTRUCTIVE TESTINGON DESTRUCTIVE TESTING

12

7

7 MARKING

MARKING AND

AND PACKING

PACKING

12

7.1

7.1 M

M

ARK ARKINGING

12

7.2

7.2 P

P

ACK ACKINGING

12

12 APPENDIX A :

APPENDIX A : RELA

RELATED DOCUM

TED DOCUMENTS

ENTS

13

13 APPENDIX B :

APPENDIX B : RECORD OF AMENDMENTS

RECORD OF AMENDMENTS

13

13 APPENDIX C : B

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1 SCOPE

This specification details the requirements for the manufacture of belt conveyor pulleys This specification details the requirements for the manufacture of belt conveyor pulleys and shafts. These pulleys are suitable for both general purpose textile reinforced belting and shafts. These pulleys are suitable for both general purpose textile reinforced belting and steel cord reinforced belting.

and steel cord reinforced belting.

2

2 TECHNICAL

TECHNICAL REQUIREMEN

REQUIREMENTS

TS TO

TO BE

BE SPECIFIED

SPECIFIED BY

BY THE

THE PURCHASER

PURCHASER

The following requirements shall be specified in tender invitation and in orders or The following requirements shall be specified in tender invitation and in orders or contracts:

contracts:

 Title, Title, reference reference number, number, issue issue and and date date of of this this specification.specification.  Title(s) Title(s) issue(s) issue(s) and and date(s) date(s) of of applicable applicable drawing(s).drawing(s).

 Diameter, Diameter, face face length length and and hub hub bore bore of of pulley pulley and and if if pulley pulley is is crowned crowned (see (see ClausesClauses 4.1 and 4.6.1).

4.1 and 4.6.1).

 Type Type of of lagging lagging if if required required (see (see Clause Clause 4.9).4.9).  The The bearing bearing code code (see (see Appendix Appendix C)C)

 Bearing Bearing centres centres of of shafts. shafts. (see (see Clause Clause 4.1)4.1)

 Type Type of of shaft shaft attachment. attachment. (see (see Clause Clause 4.2.1 4.2.1 and and 4.2.2)4.2.2)

 The The name name of of the the independent independent Quality Quality Assurance Assurance Representative. Representative. (see (see AA AA STD STD 100)100)

3 DEFINITIONS

For the purpose

For the purpose of this specification the following definitions shall apply:of this specification the following definitions shall apply: APPROVE

APPROVED D : : Approved by tApproved by the Engineer in he Engineer in writingwriting BS

BS : : British British StandardStandard DEFECTIVE

DEFECTIVE : : A A pulley pulley or or shaft shaft that that fails fails to to comply comply in in one one or or moremore respects with the requirements of

respects with the requirements of this specificationthis specification PURCHASE

PURCHASER R : : The The Company Company or or store store designated designated as as the the recipient recipient ofof finished products or services

finished products or services QUALITY ASSURANCE

QUALITY ASSURANCE REPRESENTATIVE (QAR) REPRESENTATIVE (QAR)

:

: An An independent independent inspection inspection agency agency appointed appointed andand approved by the Engineer

approved by the Engineer SANS

SANS : : South South African African National National StandardsStandards STD

STD : : An An AA AA Quality Quality Assurance Assurance ProcedureProcedure The following terms are defined in the Conditions of Contract:

The following terms are defined in the Conditions of Contract:  AA, AA, Engineer, Engineer, Company, Company, Contractor.Contractor.

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4 REQUIREMENTS

4.1 D

ESIGN AND DIMENSIONSESIGN AND DIMENSIONS

The design and dimensions of pulleys and shafts shall be in accordance with the The design and dimensions of pulleys and shafts shall be in accordance with the requirements of Figure 1 and Table 1 below. In addition, when a pulley is not designed by requirements of Figure 1 and Table 1 below. In addition, when a pulley is not designed by finite element analysis the dimensions in Table 2 shall apply.

finite element analysis the dimensions in Table 2 shall apply.

When a pulley is designed by finite element analysis the Engineer shall approve the When a pulley is designed by finite element analysis the Engineer shall approve the analysis, pulley dimensions and manufacturing details. The minimum shell thickness in analysis, pulley dimensions and manufacturing details. The minimum shell thickness in Table 2 shall apply. The stress range in weld toes shall not exceed the values for infinite Table 2 shall apply. The stress range in weld toes shall not exceed the values for infinite life given in BS 7608

life given in BS 7608 Fatigue Design and Assessment of Steel StructuresFatigue Design and Assessment of Steel Structures.. 4.1.1

4.1.1 StaStandard dimensionsndard dimensions

Standard pulley dimensions are as follows: Standard pulley dimensions are as follows:

Wide Bearing Centres Wide Bearing Centres Note:

Note: Dimension Dimension A A is is to to the the inside inside ofof the chute liners.

the chute liners.

Na

Narrow rrow Bearing CentresBearing Centres

To be used at all locations where To be used at all locations where chutes are not required.

chutes are not required. Figure 1

Figure 1 Legend:

Legend: D

D Pulley Pulley face face to to centre-line centre-line of of bearing bearing housinghousing E

E Pulley Pulley face face to to belt belt edgeedge G

G Pulley Pulley face face to to inside inside chute chute plateplate

Note: If the required shaft diameter exceeds the allowable shaft diameter then use wide Note: If the required shaft diameter exceeds the allowable shaft diameter then use wide bearing centres. bearing centres. B or C B or C B B A A G G GG E E WW EE D D FF DD W W D D D D FF

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4.1.2

4.1.2 Table 1 Table 1 - S- Standard Pulltandard Pull ey Dimensioey Dimensio nsns Belt width Belt width (mm) (mm) Face Face width width (mm) (mm) Chute Chute plates I/S plates I/S (mm) (mm) Bea

Bearing cering centresntres (mm)(mm)

Clea

Clearances forances fo rr wide centr

wide centr es. (mm)es. (mm)

Wide Narrow Wide Narrow W W F F A A B B CC Max. Max. allowable allowable shaft ø shaft ø (mm) (mm) D D E E GG 450 450 550 550 650 650 1000 1000 760 760 115 115 225 225 50 50 5050 500 500 600 600 700 700 1050 1050 810 810 115 115 225 225 50 50 5050 600 600 700 700 800 800 1150 1150 1020 1020 140 140 225 225 50 50 5050 750 750 900 900 1000 1000 1350 1350 1170 1170 140 140 225 225 75 75 5050 900 900 1050 1050 1150 1150 1550 1550 1370 1370 140 140 250 250 75 75 5050 1050 1050 1200 1200 1300 1300 1700 1700 1520 1520 140 140 250 250 75 75 5050 1200 1200 1350 1350 1450 1450 1850 1850 1680 1680 140 140 250 250 75 75 5050 1350 1350 1500 1500 1600 1600 2050 2050 1830 1830 140 140 275 275 75 75 5050 1500 1500 1700 1700 1850 1850 2300 2300 1980 1980 140 140 300 300 100 100 7575 1650 1650 1850 1850 2000 2000 2450 2450 - - - - 300 300 100 100 7575 1800 1800 2000 2000 2150 2150 2600 2600 - - - - 300 300 100 100 7575 2100 2100 2300 2300 2450 2450 2900 2900 - - - - 300 300 100 100 7575 2400 2400 2600 2600 2750 2750 3200 3200 - - - - 300 300 100 100 7575 4.1.3

4.1.3 TaTable 2 - Standable 2 - Standard Pulleys: rd Pulleys: AdditiAdditi onal Informationonal Information Shaft Shaft Diameter at Diameter at locking locking element element Type of Type of End disk End disk End disk End disk inset inset Minimum Shell Minimum Shell Thickness Thickness Min Hub Min Hub Diameter Diameter End Disk End Disk Thickness Thickness At Hub

At Hub At At Shell Shell 50 50 T T u u r r b b i i n n e e

30 30 14 14 134 134 25 25 1414 65 65 30 30 14 14 164 164 25 25 1414 75 75 30 30 14 14 194 194 30 30 1414 90 90 30 30 18 18 220 220 30 30 1818 100 100 30 30 18 18 260 260 32 32 1818 120 120 30 30 18 18 296 296 32 32 1818 130 130 30 30 18 18 316 316 40 40 1818 140 140 30 30 22 22 320 320 40 40 2222 150 150 30 30 22 22 350 350 40 40 2222 160 160 30 30 22 22 376 376 40 40 2222 180 180 35 35 22 22 360 360 50 50 2222

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200 200 35 35 25 25 420 420 50 50 2525 220 220 T T - - B B o o t t t t o o m m 38 38 25 25 454 454 101 101 2525 240 240 38 38 25 25 550 550 101 101 2525 260 260 38 38 25 25 580 580 101 101 2525 280 280 38 38 25 25 644 644 101 101 2525 300 300 38 38 25 25 656 656 101 101 2525 NOTE: NOTE: 1.

1. The The minimum hub minimum hub diameter is diameter is based on based on material with material with a a yield stress yield stress ofof 

0,2 = 280 MPa for turbine end disks and0,2 = 280 MPa for turbine end disks and 0,2 = 270 MPa for T-bottom end disks.0,2 = 270 MPa for T-bottom end disks. 2.

2. The The table table is is further based further based on on Bikon Bikon 1006 1006 (and (and equivalent) locking equivalent) locking elements elements forfor turbine end disks and Bikon 1015 (and equivalent) locking elements for T-bottom turbine end disks and Bikon 1015 (and equivalent) locking elements for T-bottom end disks. Other locking devices may be submitted for consideration by the end disks. Other locking devices may be submitted for consideration by the Engineer, in order to maintain best practice.

Engineer, in order to maintain best practice.

4.2 H

UBS ANDUBS AND

E

NDND

D

ISKSISKS

Hubs and end disks shall be manufactured from steel to SANS 1431 grade 300 WA, or Hubs and end disks shall be manufactured from steel to SANS 1431 grade 300 WA, or 350 WA, or BS 970 Part 1 grade 070M20, or cast to BS 3100 grade A2. All hubs and end 350 WA, or BS 970 Part 1 grade 070M20, or cast to BS 3100 grade A2. All hubs and end disks shall be tested prior to assembly in accordance with the method detailed in disks shall be tested prior to assembly in accordance with the method detailed in Clause 7.1. Cracks, inclusions, blow-holes and laminations shall be cause for rejection. Clause 7.1. Cracks, inclusions, blow-holes and laminations shall be cause for rejection. Suppliers of cast hubs shall be approved. Note that cast hubs are to be considered only Suppliers of cast hubs shall be approved. Note that cast hubs are to be considered only for pulleys with shafts greater than

for pulleys with shafts greater than 200 mm.200 mm.

4.3 S

HAFT AHAFT A TTACHMENTTTACHMENTSS

Pulley shaft-to-hub attachments shall be by means of keyless locking elements. The Pulley shaft-to-hub attachments shall be by means of keyless locking elements. The elements shall be so chosen as to be capable of transmitting the maximum torque that elements shall be so chosen as to be capable of transmitting the maximum torque that can be developed by the pulley shaft.

can be developed by the pulley shaft. 4.3.1

4.3.1 When When a a pulley pulley is is designed by designed by finite finite element element analysis analysis the the calculated bending calculated bending momentmoment applied to the locking element under start-up loads, and the angular distortion of the applied to the locking element under start-up loads, and the angular distortion of the locking element under start-up loads, must not exceed the recommendations of the locking element under start-up loads, must not exceed the recommendations of the locking element suppliers.

locking element suppliers. 4.3.2

4.3.2 Shrink Shrink fit fit shaft shaft attachment:attachment:

While the preference is to use keyless locking elements as shaft attachments, when While the preference is to use keyless locking elements as shaft attachments, when shrink fit shaft attachments are specified, shafts and bosses shall be machined to BS shrink fit shaft attachments are specified, shafts and bosses shall be machined to BS 4500 and shall be a shaft based interference fit. Note that shrink-fit attachments will 4500 and shall be a shaft based interference fit. Note that shrink-fit attachments will require the approval of the Engineer.

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4.4 P

ULLEY SHELLSULLEY SHELLS 4.4.1

4.4.1 Pulley Pulley shells shells shall shall be be manufactured from manufactured from steel steel that that complies complies with with the the requirements ofrequirements of SANS 1431 grade 300 WA or 350 WA.

SANS 1431 grade 300 WA or 350 WA. 4.4.2

4.4.2 The The shell shell shall shall be be machined to machined to be be concentric wiconcentric with th the the shaft shaft within within the the Total Indicated Total Indicated Run- Run-out permitted in SANS 1669-1.

out permitted in SANS 1669-1. 4.4.3

4.4.3 The The tolerance on tolerance on the the pulley pulley diameter shall diameter shall be be + + 2,0 2,0 mm. This mm. This tolerance shall tolerance shall be be applied toapplied to both bare and lagged pulleys.

both bare and lagged pulleys. 4.4.4

4.4.4 For pulleys with face For pulleys with face width suitable width suitable for belt for belt widths up widths up to and to and including 900 including 900 mm, themm, the tolerance on the face width shall be ±3,0 mm. For pulleys with face width suitable for belt tolerance on the face width shall be ±3,0 mm. For pulleys with face width suitable for belt width greater than 900 mm, the tolerance on the face width shall be ±6,0 mm.

width greater than 900 mm, the tolerance on the face width shall be ±6,0 mm. 4.4.5

4.4.5 The The shell shall shell shall have a have a minimum thickness minimum thickness after machining after machining as as indicated in indicated in Table 2.Table 2. Deviation from the minimum shell thickness after machining shall not exceed 12% of the Deviation from the minimum shell thickness after machining shall not exceed 12% of the nominal thickness at any point on the shell.

nominal thickness at any point on the shell. 4.4.6

4.4.6 The The preferred shell preferred shell diameters diameters shall shall be be limited limited to to the the range range given given in in Table Table 3.3. 4.4.7

4.4.7 Other Other shell shell diameters diameters may may be be submitted submitted for for consideration consideration by by the the Engineer.Engineer. Table 3

Table 3 - S- Standard putandard pu lleyslleys : Shell Diameter: Shell Diameter 160 160 630 630 12501250 200 200 710 710 14001400 250 250 800 800 16001600 315 315 900 900 18001800 400 400 1000 1000 20002000 500 1120 500 1120

4.5 S

HAFTSHAFTS Table 4

Table 4 - Pre- Preferred Bearing ferred Bearing JouJou rnal Sizesrnal Sizes 50 50 115 115 180 180 260260 65 65 125 125 190 190 280280 75 75 140 140 200 200 300300 90 90 150 150 220220 100 160 240 100 160 240

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4.5.1

4.5.1 Shafts Shafts shall shall be be manufactured from manufactured from steel steel that that complies complies with with the the requirements of requirements of BS BS 970970 Part 1 grade 070M20 (EN3A). Shafting of finished diameter less than 130 mm may be Part 1 grade 070M20 (EN3A). Shafting of finished diameter less than 130 mm may be supplied as bright shafting. Shafting of finished diameter 130 mm and greater shall be supplied as bright shafting. Shafting of finished diameter 130 mm and greater shall be normalised. Steel conforming to grade 080M40 (EN8) and 070M55 (EN9) is not to be normalised. Steel conforming to grade 080M40 (EN8) and 070M55 (EN9) is not to be used unless approved by the Engineer.

used unless approved by the Engineer. 4.5.2

4.5.2 Shafts shall be sized Shafts shall be sized so that so that at all at all points the points the stresses do stresses do not exceed not exceed 90% of 90% of the yithe yieldeld stress under start-up belt tensions and drive torques.

stress under start-up belt tensions and drive torques. 4.5.3

4.5.3 All All contact contact surfaces surfaces for for hub hub connections, connections, bearings, bearings, seals seals and and couplings couplings shall shall be be machinedmachined round to a surface texture not rougher than R0,8

round to a surface texture not rougher than R0,8 m. Undercuts, reliefs and grooves arem. Undercuts, reliefs and grooves are not permitted.

not permitted. 4.5.4

4.5.4 The The bearing diameter bearing diameter shall shall be be restricted to restricted to the range the range shown shown in in Table Table 4. 4. Where Where bearingbearing journals a

journals are smalre smaller in ler in diameter diameter than ththan that at at at the locking the locking element, element, the shouthe shoulder at lder at the turthe turn- n-down shall be provided with a fillet, with a radius figured at

down shall be provided with a fillet, with a radius figured at

2

2 ))

((

3

D D d d r r

_



_or_or r = (0,1·d), whichever is the greater.

r = (0,1·d), whichever is the greater. Here,

Here, D

D = = major major (base) (base) diameterdiameter d

d = = minor minor (journal) (journal) diameterdiameter 4.5.5

4.5.5 Where Where the the bore bore of of the the coupling, coupling, shaft shaft mounted reduction mounted reduction unit unit or or holdback holdback is is smaller smaller thanthan the journal diameter of the shaft, the shoulder at the turn-down shall be provided with a the journal diameter of the shaft, the shoulder at the turn-down shall be provided with a fillet in accordance with 5.1.4 above.

fillet in accordance with 5.1.4 above. 4.5.6

4.5.6 When When a a pulley is pulley is not not designed by designed by finite finite element analysis element analysis the the following rules following rules shall shall bebe applied, with the shaft loaded by the shear forces applied by the end discs, but ignoring applied, with the shaft loaded by the shear forces applied by the end discs, but ignoring the moments applied by the discs:

the moments applied by the discs:

The maximum allowable deflection of the shaft at the centre of the hub connection shall The maximum allowable deflection of the shaft at the centre of the hub connection shall be designed at 14,5 milli-radians ( 0°-5’-0”), in accordance with the suppliers be designed at 14,5 milli-radians ( 0°-5’-0”), in accordance with the suppliers recommendations. These deflection limits are based on the locking element types noted in recommendations. These deflection limits are based on the locking element types noted in 4.1.3 Note 2 above. Limits for other locking devices may be submitted for consideration by 4.1.3 Note 2 above. Limits for other locking devices may be submitted for consideration by the Engineer, in order to maintain best practice.

the Engineer, in order to maintain best practice.

When the proposed design incorporates a reduction in shaft diameter, the stress factors When the proposed design incorporates a reduction in shaft diameter, the stress factors shall be applied to ensure that the stresses at these points do not exceed 55 MPa. All shall be applied to ensure that the stresses at these points do not exceed 55 MPa. All external corners shall be chamfered to 3 mm at 45°.

external corners shall be chamfered to 3 mm at 45°. 4.5.7

4.5.7 When When a a pulley pulley is is designed by designed by finite finite element analysis element analysis the the following following rules rules shall shall be be applied:applied: The minimum shaft diameter shall be calculated using the CEMA formula using the The minimum shaft diameter shall be calculated using the CEMA formula using the running loads and torque. The bending moment on the locking element must also not running loads and torque. The bending moment on the locking element must also not exceed the manufacturer’s maximum allowable bending moment under start-up loads exceed the manufacturer’s maximum allowable bending moment under start-up loads (see 4.3.1). This may require a different diameter. The maximum of these diameters shall (see 4.3.1). This may require a different diameter. The maximum of these diameters shall be used, and rounded up to the next standard diameter in Table 2.

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When the design incorporates a reduction in shaft diameter the reduced diameter shall be When the design incorporates a reduction in shaft diameter the reduced diameter shall be determined by the CEMA shaft formula, with the shaft step down concentration factors determined by the CEMA shaft formula, with the shaft step down concentration factors taken into account. This diameter is to be rounded up to the next standard diameter in taken into account. This diameter is to be rounded up to the next standard diameter in Table 4.

Table 4. 4.5.8

4.5.8 Flame Flame spraying spraying plating, plating, welding, welding, stray stray arcing arcing and and weld weld spatter spatter on on shafts shafts is is not not permitted.permitted. 4.5.9

4.5.9 Keys Keys and and Keyways: Keyways: keys keys and and keyways keyways shall shall comply comply with with the the requirements of requirements of BS BS 4235,4235, Part 1.

Part 1. 4.5.10

4.5.10 When shrink-fit When shrink-fit shaft attachments shaft attachments are used, are used, the keys the keys shall shall not protrude not protrude beyond the beyond the outerouter hub face. Keys and keyways for shaft extensions beyond the bearings shall be provided to hub face. Keys and keyways for shaft extensions beyond the bearings shall be provided to suit the attachments required for the application. See paragraph 4.3.2

suit the attachments required for the application. See paragraph 4.3.2

4.6 B

EARINGS AND MOUNTINGSEARINGS AND MOUNTINGS 4.6.1

4.6.1 Bearings Bearings shall shall comply comply with with the the boundary boundary dimension dimension requirements of requirements of ISO:R15 ISO:R15 for for radialradial bearings and shall be referenced by the Purchaser with the relevant AA code (Appendix bearings and shall be referenced by the Purchaser with the relevant AA code (Appendix C).

C). 4.6.2

4.6.2 Bearings shall be Bearings shall be of of the double the double row, self-aligning, row, self-aligning, spherical spherical roller roller type 222 type 222 series series forfor shafts up to and including 140 mm diameter and the 231 series for shafts greater than 140 shafts up to and including 140 mm diameter and the 231 series for shafts greater than 140 mm diameter. Bearings shall be designed for a life of 100 000 hours B10.

mm diameter. Bearings shall be designed for a life of 100 000 hours B10. 4.6.3

4.6.3 Lubrication shall Lubrication shall be be through through a a circumferential groove circumferential groove and and three three equally equally spaced spaced holes holes inin the outer race. The lubricant shall be grease type GPG-2LXEP in accordance with the the outer race. The lubricant shall be grease type GPG-2LXEP in accordance with the requirements of AA standard specification 166014.

requirements of AA standard specification 166014. 4.6.4

4.6.4 In In all all cases, cases, the reference the reference to to bearing centres bearing centres shall shall be construed be construed as the as the centre of centre of thethe bearing housing holding down bolts, where these differ from the actual centre-line of the bearing housing holding down bolts, where these differ from the actual centre-line of the bearing inside the housing. This normally applies to bearings in housings for shafts in bearing inside the housing. This normally applies to bearings in housings for shafts in excess of

excess of 140 mm. The pulley manufacturer shall therefore mount the bearings on the140 mm. The pulley manufacturer shall therefore mount the bearings on the shafts in such a way that this requirement is satisfied.

shafts in such a way that this requirement is satisfied. 4.6.5

4.6.5 Bearing housings: shall be Bearing housings: shall be of of the horizontally the horizontally split type split type in in accordance with accordance with thethe requirements of BS 5646 Part 4. Adequate sealing arrangements shall be provided.

requirements of BS 5646 Part 4. Adequate sealing arrangements shall be provided. 4.6.6

4.6.6 Lubrication shall Lubrication shall be be facilitated facilitated by by type type 21A 21A button button head head grease grease nipples nipples in in accordance withaccordance with the requirements of BS 1486 Part 2.

the requirements of BS 1486 Part 2. 4.6.7

4.6.7 Bearing Bearing sole sole plates plates shall shall be be in in accordance with accordance with the the requirements of requirements of AA AA standard standard drawingdrawing number Y1315.

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4.7 S

HELLHELL

C

ROWNINGROWNING 4.7.1

4.7.1 Crowning. (see Crowning. (see Clause Clause 2.3). 2.3). If If required, required, crowning crowning shall shall be be arranged arranged either either asas 4.7.1.1

4.7.1.1 Edge-crowning, Edge-crowning, where where the the outerouter11//66 of the pulley face width is tapered at a slope of 1:50, of the pulley face width is tapered at a slope of 1:50,

with the centre

with the centre22//33 flat. The dimension at the pulley centre shall be the nominal diameter of flat. The dimension at the pulley centre shall be the nominal diameter of

the pulley. The original material thickness of shell shall be sufficient to allow for machining the pulley. The original material thickness of shell shall be sufficient to allow for machining to end thickness dimensions as specified in Table 2.

to end thickness dimensions as specified in Table 2. or

or 4.7.1.2

4.7.1.2 Centre-crowning, where the face of the pulley is Centre-crowning, where the face of the pulley is tapered at a slope of 1 tapered at a slope of 1 : 100 with the: 100 with the minor diameter at the ends of the pulley face. The dimension at the pulley edge shall be minor diameter at the ends of the pulley face. The dimension at the pulley edge shall be the nominal diameter of the pulley. The original material thickness of shell shall be the nominal diameter of the pulley. The original material thickness of shell shall be sufficient to allow for machining to end thickness dimensions as specified in Table 2.

sufficient to allow for machining to end thickness dimensions as specified in Table 2. 4.7.1.3

4.7.1.3 Crowning of Crowning of pulleys for pulleys for use with use with steelcord reinforced belting steelcord reinforced belting is generally is generally not preferred.not preferred. See SANS 1669:1996

See SANS 1669:1996

4.8 W

ELDINGELDING 4.8.1

4.8.1 Welding: Welding: All All welds welds shall shall comply comply with with the the requirements requirements of of AWS AWS D1.1.D1.1. 4.8.2

4.8.2 Weld Weld procedures procedures shall shall be be submitted submitted for for approval approval at at time time of of tender.tender. 4.8.3

4.8.3 Weld Weld quality: quality: Butt Butt and and fillet fillet welds welds shall shall have have complete penetration complete penetration and and fusion fusion for for the the fullfull length of the weld and shall be free from undercuts, overlaps or bead surface defects. length of the weld and shall be free from undercuts, overlaps or bead surface defects. Finished welds shall be free of cracks, porosity and inclusions.

Finished welds shall be free of cracks, porosity and inclusions. 4.8.4

4.8.4 Weld Weld joint joint preparation. All preparation. All weld weld joint joint preparation shall preparation shall be be available available for for inspection by inspection by thethe Quality Assurance Representative before welding is commenced. The weld preparation Quality Assurance Representative before welding is commenced. The weld preparation for butt welding may be modified within the limits AWS D1.1 in order to achieve full for butt welding may be modified within the limits AWS D1.1 in order to achieve full penetration welds. Such modification shall be submitted for approval.

penetration welds. Such modification shall be submitted for approval. 4.8.5

4.8.5 Shell Shell butt butt weld weld method: The method: The pulley pulley shell shell butt butt joint joint shall shall be be internally welded internally welded and and shall shall bebe dressed to a smooth profile inside and outside the shell.

dressed to a smooth profile inside and outside the shell. 4.8.6

4.8.6 Air Air ventvent A

A 4 4 mm mm diameter diameter air air vent vent hole hole shall shall be be provided provided for for pulleys pulleys having having either either shrink shrink fit fit oror keyless locking element shaft attachments in order to prevent 'blow-back' on final seal run keyless locking element shaft attachments in order to prevent 'blow-back' on final seal run and distortion on vulcanising of lagging (if used). The hole shall be located outside of the and distortion on vulcanising of lagging (if used). The hole shall be located outside of the heat affected zone of the disk-to shell weld.

heat affected zone of the disk-to shell weld.

This hole shall be sealed with a 4 mm diameter parallel dowel pin to DIN 6325 of a length This hole shall be sealed with a 4 mm diameter parallel dowel pin to DIN 6325 of a length not less than the diaphragm thickness.

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4.9 S

TRESS RELIEVING AND NORMALISINGTRESS RELIEVING AND NORMALISING NOTE

NOTE 1.

1. Details of Details of heat treatment heat treatment furnaces and furnaces and recording devices recording devices shall be shall be submitted forsubmitted for approval.

approval. 2.

2. The furnace The furnace atmosphere shall atmosphere shall be so be so controlled as controlled as to avoid to avoid oxidation during oxidation during thethe heating and soaking periods.

heating and soaking periods. There shall be no There shall be no direct flame on the direct flame on the treated article.treated article. 4.9.1

4.9.1 Stress Stress relieving of relieving of pulleys pulleys shall shall be be at at a a temperature of temperature of 600/650°C and 600/650°C and the the heating andheating and cooling cycles shall be as specified in Clauses 4.8.3 and 4.8.4.

cooling cycles shall be as specified in Clauses 4.8.3 and 4.8.4. 4.9.2

4.9.2 Normalising of shafts Normalising of shafts shall shall be be at at a a temperature of temperature of 880/910°C and 880/910°C and the the heating and heating and coolingcooling cycles shall be as specified in Clauses 4.8.3 and 4.8.5.

cycles shall be as specified in Clauses 4.8.3 and 4.8.5. 4.9.3

4.9.3 Heating Heating cycle: cycle: The The temperature of temperature of the the furnace at furnace at the the commencement of commencement of the the treatmenttreatment cycle shall not exceed 400°C and the rate of increase in temperature above 400°C shall cycle shall not exceed 400°C and the rate of increase in temperature above 400°C shall not exceed the following:

not exceed the following: 4.9.3.1

4.9.3.1 Not more than Not more than 200°C per hour for 200°C per hour for a thickness of a thickness of diaphragm plate up to diaphragm plate up to and including 25and including 25 mm.

mm. 4.9.3.2

4.9.3.2 Not Not more more thanthan tt 5000 5000

°C/ hour for a diaphragm plate over 25 mm in thickness where °C/ hour for a diaphragm plate over 25 mm in thickness where tt is the diaphragm thickness in mm.is the diaphragm thickness in mm.

4.9.3.3

4.9.3.3 When the When the item has attained item has attained a uniform temperature the a uniform temperature the temperature shall be temperature shall be maintainedmaintained for a period of one hour for diaphragm thicknesses up to and including 25 mm. For for a period of one hour for diaphragm thicknesses up to and including 25 mm. For diaphragms over 25 mm thick allow an additional 2 minutes for each mm in thickness diaphragms over 25 mm thick allow an additional 2 minutes for each mm in thickness above 25 mm.

above 25 mm. 4.9.4

4.9.4 Cooling Cooling cycle, cycle, stress relieving: stress relieving: The component The component shall shall be be cooled in cooled in the furnace the furnace at at a a rate notrate not exceeding 250°C per hour for thicknesses of diaphragm plate up to and including 25 mm. exceeding 250°C per hour for thicknesses of diaphragm plate up to and including 25 mm. 4.9.4.1

4.9.4.1 For diaphragm plate thicknesses above 25 mm the cooling rate shall not exceedFor diaphragm plate thicknesses above 25 mm the cooling rate shall not exceed tt

6250 6250

°C /hour where

°C /hour where tt is the diaphragm thickness in mm. is the diaphragm thickness in mm. 4.9.4.2

4.9.4.2 Components shall be Components shall be removed from the furnace removed from the furnace at a at a temperature of 250°C and temperature of 250°C and cooled incooled in still air.

still air. 4.9.5

4.9.5 Cooling cyclCooling cycle, normalising: e, normalising: Shafts Shafts shall be shall be cooled in cooled in still still air air from the from the maximummaximum temperature required in this specification.

temperature required in this specification.

4.10 L

AGGING AGGING

See also SANS 1669-2: 2005 See also SANS 1669-2: 2005

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4.10.1

4.10.1 Lagging typLagging typ e and patterne and pattern The lagging pattern

The lagging pattern shall be one shall be one of the following as specified by the Purchaser.of the following as specified by the Purchaser. (a) Plain

(a) Plain Non Non drive drive bend bend pulleys.pulleys. (b)

(b) Chevron Chevron Direction of Direction of drive drive to to be be advised advised to to the the Contractor. Contractor. Note Note this this patternpattern is not preferred.

is not preferred. (c)

(c) Diamond. Diamond. This This pattern pattern may may be be used used on on driver driver pulleys pulleys and and non-drive non-drive pulleyspulleys where the contact angle

where the contact angle exceeds ±150°exceeds ±150° (d)

(d) Ceramic Ceramic tiles tiles both drive both drive and and non-drive. non-drive. note note that that dimpled dimpled tiles tiles are are required required forfor drive pulleys.

drive pulleys. 4.10.2

4.10.2 Lagging Lagging materiamateriall

The lagging material shall be one of the following as specified by the Purchaser. The lagging material shall be one of the following as specified by the Purchaser. (a)

(a) Natural Natural rubber rubber having having a a Shore Shore A A hardness hardness of of 65° 65° - - 70° 70° for for non non flame-retardantflame-retardant applications.

applications. (b)

(b) Neoprene having Neoprene having a a Shore Shore A A hardness of hardness of 65° 65° + + 5° 5° for for flame-retardaflame-retardantnt applications.

applications. The material

The material shall comply with the requirements of AA specification 171001.shall comply with the requirements of AA specification 171001.

Other lagging materials, such as ceramic tiles, may be submitted for consideration by the Other lagging materials, such as ceramic tiles, may be submitted for consideration by the Engineer, in order to maintain best practice.

Engineer, in order to maintain best practice. 4.10.3

4.10.3 Lagging ThicknessLagging Thickness

The lagging thickness shall be as specified by the Purchaser and shall be not less than The lagging thickness shall be as specified by the Purchaser and shall be not less than 10mm in the case of chevron or diamond profiled lagging.

10mm in the case of chevron or diamond profiled lagging. 4.10.4

4.10.4 Surface PreparationSurface Preparation

The surfaces to be lagged shall be abrasive blast cleaned to SA 2½ finish with a surface The surfaces to be lagged shall be abrasive blast cleaned to SA 2½ finish with a surface profile of 40 to 65 microns in accordance with requirements of AA specification 164050. profile of 40 to 65 microns in accordance with requirements of AA specification 164050. 4.10.5

4.10.5 CuringCuring

Lagging shall be steam cured in an autoclave in accordance with the requirements of Lagging shall be steam cured in an autoclave in accordance with the requirements of SANS 1198.

SANS 1198.

Where the lagging is applied on site, the adhesive curing times as specified by the Where the lagging is applied on site, the adhesive curing times as specified by the suppliers shall be applied.

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4.10.6

4.10.6 Ad Ad heshesioio nn

An adhesion test sh

An adhesion test sh all be conducted on all be conducted on every batch of laggevery batch of lagg ing material in accordaing material in accordance withnce with the requirements of SANS 1198 and SANS 1669t 2. Adhesive used shall be from the the requirements of SANS 1198 and SANS 1669t 2. Adhesive used shall be from the same batch as used for the lagging process.

same batch as used for the lagging process.

4.11 B

AL ALANCINGANCING All pulley

All pulleys shall be s shall be balanced in accordance witbalanced in accordance with SANS 1169.h SANS 1169.

Note: Welding of fitments to the end disks for balancing purposes is not permitted. Note: Welding of fitments to the end disks for balancing purposes is not permitted.

4.12 C

ORROSION PROTECTIONORROSION PROTECTION

Prior to painting, all rust, mill scale, grease, oil and other foreign matter shall be removed. Prior to painting, all rust, mill scale, grease, oil and other foreign matter shall be removed. The shell, when not lagged, the hubs and end disks and diaphragms shall be primed with The shell, when not lagged, the hubs and end disks and diaphragms shall be primed with one coat of single pack wash primer of not less than 20

one coat of single pack wash primer of not less than 20 m thickness and a single coat ofm thickness and a single coat of chlorinated rubber, resin based paint of not less than 30

chlorinated rubber, resin based paint of not less than 30 m thicknessm thickness..

5

5 QUAL

QUALITY

ITY ASSURA

ASSURANCE

NCE PROVISION

PROVISION

The quality management system shall comply with the requirements of SABS ISO 9001. The quality management system shall comply with the requirements of SABS ISO 9001. The requirements of AA STD 100 shall apply.

The requirements of AA STD 100 shall apply.

6

6 TEST

TEST AND

AND INSPECTION

INSPECTION METHODS

METHODS

6.1 N

ON DESTRUCTIVE TESTINGON DESTRUCTIVE TESTING

The hubs and end disks, shell, and shaft shall be non-destructively (U/S and MPI) tested The hubs and end disks, shell, and shaft shall be non-destructively (U/S and MPI) tested in accordance with the requirements of AA specification 999001 before assembly. Welded in accordance with the requirements of AA specification 999001 before assembly. Welded regions shall be re-tested after welding.

regions shall be re-tested after welding.

7

7 MARKING

MARKING AND

AND PACKING

PACKING

7.1 M

ARK ARKINGING

The following data shall be clearly and permanently marked on both vertical faces of the The following data shall be clearly and permanently marked on both vertical faces of the shaft and on one end of the shell rim. No marking shall extend into a welded zone.

shaft and on one end of the shell rim. No marking shall extend into a welded zone.  Contractor's Contractor's name, name, trade trade name name or or trade trade mark.mark.

 Month Month and and year year of of manufacture.manufacture.  QAR's QAR's logo.logo.

 AA AA order order number.number.

7.2 P

ACK ACKINGING

Immediately after acceptance by the QAR, all exposed shaft surfaces shall be protected Immediately after acceptance by the QAR, all exposed shaft surfaces shall be protected against corrosion and accidental damage. Precautions shall be taken by the Contractor to against corrosion and accidental damage. Precautions shall be taken by the Contractor to ensure that the pulley assemblies are not damaged during handling and transportation. ensure that the pulley assemblies are not damaged during handling and transportation.

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APPENDIX A

APPENDIX A : REL: REL ATED DOCUMENTSATED DOCUMENTS AAC Drawing

AAC Drawing Y1315 Y1315 : : Standard solStandard sole plates for e plates for conveyors (dimconveyors (dimensions)ensions) AA Specifi

AA Specification 164/5cation 164/50 0 : : Corrosion protCorrosion protection of steection of steelwork with elwork with coatingscoatings AA Specifi

AA Specification 171/1 cation 171/1 : : Fire resistaFire resistant elastomers font elastomers for use undergrounr use underground in fiery mid in fiery minesnes AA Specif

AA Specification 999/1 ication 999/1 : : Non-destructNon-destructive examinatiive examination for flat son for flat steel componentsteel components AA STD 100

AA STD 100 : : Quality management systems fQuality management systems for critical or critical and major materiand major materialal BS

BS 970 970 Part Part 1 1 : : Wrought steels Wrought steels for for mechanical mechanical and and allied allied engineeringengineering purposes.

purposes. BS

BS 3100 3100 : : Specification for Specification for steel steel castings castings for for general general engineerinengineeringg purposes

purposes BS

BS 1486 1486 Part Part 2 2 : : Heavy Heavy duty duty lubricating lubricating nipplesnipples BS

BS 4235 4235 : : Metric Metric keys keys and and keywayskeyways BS

BS 4500 4500 : : ISO ISO limits limits and and fitsfits AWS/ANSI

AWS/ANSI D1.1-2006 D1.1-2006 : : Structural Structural welding code - welding code - SteelSteel BS

BS 5646 5646 Part Part 4 4 : : SpecificatiSpecification on for for plummer plummer block block housingshousings DIN

DIN 6325 6325 : : Parallel Parallel pins, pins, hardened, hardened, tolerance tolerance zone zone M6M6 SANS

SANS 1173 1173 : : General purpose General purpose textile textile reinforced reinforced conveyor conveyor beltingbelting SANS

SANS 1431 1431 : : Weldable Weldable structurastructural l steelsteel SANS

SANS 1198 1198 : : The The production production and and quality quality of of rubber rubber linings linings on on steel steel pipes,pipes, pipe fittings and vessels

pipe fittings and vessels SANS

SANS 1669 1669 parts parts 1&2 1&2 : : Conveyor Conveyor Belt Belt PulleysPulleys APPENDIX B

APPENDIX B : RECORD OF A: RECORD OF A MENDMENTSMENDMENTS Issue

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APPENDIX C :

APPENDIX C : BEABEA RING CODINGRING CODING Bearings listed on AA equipment

Bearings listed on AA equipment schedules shall be coded as schedules shall be coded as follows:follows: xxx

xxx C/T L/F (C/T L/F (S)S) Where:

Where: xxx xxx is is numeric numeric and and is is the the shaft shaft diameter diameter in in mm.mm. C/T

C/T is either is either C or TC or T and indicates whether the housing is a closed end or through and indicates whether the housing is a closed end or through shaft.

shaft. L/F

L/F is either is either L or FL or F and indicates whether the bearing is located or and indicates whether the bearing is located or floating.floating. (S)

(S) is either present or absent and indicates whether or not a flinger ring is is either present or absent and indicates whether or not a flinger ring is required.

required. Example

Example

Code 90TL indicates a bearing unit to suit a shaft of 90 mm diameter with the shaft through the Code 90TL indicates a bearing unit to suit a shaft of 90 mm diameter with the shaft through the bearing and the bearing located in the housing. No flinger is required.

bearing and the bearing located in the housing. No flinger is required.

The locating bearing is placed at the coupling side of a through shaft, with the non-driving end The locating bearing is placed at the coupling side of a through shaft, with the non-driving end floating. Where the shaft has a double

floating. Where the shaft has a double extension for a second drive, the locating bearing is placed extension for a second drive, the locating bearing is placed toto best suit the arrangement. For a shaft with a double extension for a holdback device, the locating best suit the arrangement. For a shaft with a double extension for a holdback device, the locating bearing is placed at the coupling.

bearing is placed at the coupling. Pulley shaft extensions

Pulley shaft extensions

For the range of bearings permitted by this specification, the values recommended for the extension For the range of bearings permitted by this specification, the values recommended for the extension of the pulley shaft through the bearings of

of the pulley shaft through the bearings of housings with closed ends are as shown in Table 5.housings with closed ends are as shown in Table 5. The dimensions shown are given from the

The dimensions shown are given from the centreline of the housing which may differ from that of centreline of the housing which may differ from that of thethe bearing. The centreline dimension indicated on the drawing generally is that of the housing or bolt bearing. The centreline dimension indicated on the drawing generally is that of the housing or bolt hole centres. hole centres. TABLE 5 TABLE 5 Shaft Shaft dia dia Bearing Bearing code

code ExtExt

Shaft Shaft dia dia Bearing Bearing code

code ExtExt 2 2 50 50 CL CL or or F F 34 34 150 150 150 150 CL CL or or F F 7070 65 65 65 65 CL CL or or F F 42 42 160 160 160 CL 160 CL or or F F 7272 75 75 75 75 CL CL or or F F 50 50 180 180 180 CL 180 CL or or F F 8888 90 90 90 90 CL CL or or F F 55 55 200 200 200 CL 200 CL or or F F 9292 100 100 100 100 CL CL or or F F 60 60 220 220 220 220 CL CL or or F F 100100 115 115 115 115 CL CL or or F F 68 68 240 240 240 240 CL CL or or F F 108108 125 125 125 125 CL CL or or F F 72 72 260 260 260 260 CL CL or or F F 108108 140 140 140 140 CL CL or or F F 85 85 300 300 300 300 CL CL or or F F 130130