1、Specification for belt drives Endless wedge belts, endless V-belts, banded wedge belts, banded V-belts and their corresponding pulleysICS 21.220.10NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDBS 3790:2006IncorporatingCorrigendum No. 1Publishing and copyright
2、informationThe BSI copyright notice displayed in this document indicates when the document was last issued. BSI 2006ISBN 0 580 48017 8The following BSI references relate to the work on this standard:Committee reference MCE/10Draft for comment 05/30134325 DCPublication historyFirst published, Septemb
3、er 1964Second edition, December 1973Third edition, October 1981Fourth edition, June 1995Fifth edition, April 2006BS 3790:2006Amendments issued since publicationAmd. no. Date Text affected16655Corrigendum No. 1September 2006 Correction to value in Table 2 (spacing for belt section D) BSI 2006 iBS 379
4、0:2006ContentsForeword ii1 Scope 12 Normative references 13 Terms and definitions 14 Wedge belts, V-belts and banded belts 45 Grooved pulleys 9AnnexesAnnex A (normative) Determination of belt datum length 17Annex B (informative) Storage of belts 18Annex C (informative) Recommendations for drive desi
5、gn 19Annex D (normative) Tests for electrical resistance of belts 27Annex E (informative) Recommended practice for installation tension in belt drives and calculation of resultant force imposed on the shaft 29Bibliography 33List of figuresFigure 1 Belt cross-sections 2Figure 2 Basic belt constructio
6、n 5Figure 3 Pulley limiting rotational speed indicating limits for static or dynamic balancing 12Figure 4 Multi-groove pulley cross-section 13Figure A.1 Measuring pulley and apparatus for measuring beltlength 17Figure C.1 Selection of wedge belt cross-section 25Figure C.2 Selection of V-belt cross-s
7、ection 26Figure D.1 Apparatus for measuring the electrical resistance of belts 28Figure E.1 Belt deflection measurement 32List of tablesTable 1 Wedge belt and V-belt cross-section dimensions 2Table 2 Banded belts belt spacing 3Table 3 Tolerances and force requirements when measuringnew belts 6Table
8、4 Dimensions of pulleys for measuring lengths of new belts 6Table 5 Nominal datum lengths of wedge belts and V-belts and permitted tolerances 7Table 6 Surface finish of pulleys 9Table 7 Dimensions of standard grooved pulleys for wedge and V-belt drives 13Table 8 Preferred pulley datum diameters 14Ta
9、ble 9 Recommended minimum pulley datum diameters 16Table A.1 Centre distance variation %C on measuring fixture 18Table C.1 Service factors for belt drives 23Table C.2 Standard base lengths Lofor power rating formulae 24Table E.1 Deflection force required for measuring installation tension in wedge a
10、nd V-belt drives using single or multiple belts 31Summary of pagesThis document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 33 and a back cover.BS 3790:2006ii BSI 2006 ForewordPublishing informationThis British Standard was published by BSI and came into effect on 28 A
11、pril 2006. It was prepared by Technical Committee MCE/10, Belts and pulley drives. A list of organizations represented on this committee can be obtained on request to its secretary.SupersessionThis British Standard supersedes BS 3790:1995, which is withdrawn.Relationship with other publicationsThis
12、revision of BS 3790 is for all practical purposes technically related to the following standards prepared by the International Organization for Standardization (ISO):BS ISO 155, BS ISO 254, BS ISO 5287, ISO 1081, ISO 1813, ISO 4183, ISO 4184, ISO 5292, ISO 9608.NOTE See bibliography for full details
13、 of these standards.“E” Section V-belts, which form part of ISO 4183 and ISO 4184, are excluded from this standard because of lack of demand in the United Kingdom.Information about this documentThis new edition represents a full revision of the standard, and introduces the following principal change
14、s:The test for fire resistance (BS 3790:1995, Annex G) has been deleted due to the fact that no test method currently exists that meets the requirements of the ATEX Directive 1 and BS EN 13463-5:2003, 7.2.1)Banded belts, i.e. belts joined across the top surface, have been included. The use of the te
15、rm “pitch” used in previous versons of BS 3790 has been replaced by “datum” as used in international standards.Presentational conventionsThe provisions of this standard are presented in roman (i.e. upright) type. Its requirements are expressed in sentences in which the principal auxiliary verb is “s
16、hall”.Commentary, explanation and general informative material is presented in smaller italic type, and does not constitute a normative element.Requirements in this standard are drafted in accordance with The BSI guide to standardization Section 2: Rules for the structure, drafting and presentation
17、of British Standards, subclause 11.3.1, which states, “Requirements should be expressed using wording such as: When tested as described in Annex A, the product shall .”. This means that only those products that are capable of passing the specified test will be deemed to conform to this standard.Cont
18、ractual and legal considerationsThis publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.1)Currently under revision. BSI 2006 1BS 3790:20
19、061 ScopeThis British Standard specifies the dimensions and certain other properties of endless wedge belts, V-belts and equivalent banded belts and their corresponding grooved pulleys, when used for power transmission.Recommendations and information on the design, selection and installation of driv
20、e assemblies are given in Annex C and Annex E. Recommendations on the storage of belts are given in Annex B.This standard does not apply to industrial variable speed drives employing pulleys with movable flanges, or to drives specified in BS 3733 or BS ISO 5287.2 Normative referencesThe following re
21、ferenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.BS 1913:1990, Specification for soft soapBS ISO 254:1998, Belt dri
22、ves Pulleys Quality, finish and balance3 Terms and definitionsFor the purposes of this British Standard, the following terms and definitions apply.3.1 wedge or V-belt or banded belt drivedrive that consists of one or more trapezoidal cross-section belts mounted on grooved pulleysNOTE The profiles of
23、 the belts and of the pulley grooves are such that the belts come into contact with only the sides of the pulley grooves and not with the base of the grooves.3.2 wedge beltnarrow V-belt belt in which the outline formed by the base, sides and top of the belt approximates to a trapezium characterized
24、by a relative height of approximately 0.95 WdNOTE 1 Wedge belts are commonly known as narrow V-belts in international standards.NOTE 2 See Figure 1a) and Table 1.3.3 V-beltclassical V-beltbelt in which the outline formed by the base, sides and top of the belt approximates to a trapezium characterize
25、d by a relative height of approximately 0.73 WdNOTE 1 V-belts are commonly known as classical V-belts in international standards.NOTE 2 See Figure 1b) and Table 1.BS 3790:20062 BSI 2006 3.4 banded beltbelt made up from two or more wedge belts or V-belts joined across the top surface with a reinforce
26、d band of flexible materialNOTE See Figure 1c) and Table 2.Figure 1 Belt cross-sectionsa) Wedge belt b) V-beltc) Banded beltNOTE See Table 1 and Table 2.WWdTAWWdTAebebTable 1 Wedge belt and V-belt cross-section dimensionsCross-section symbolDatumwidth, WdmmNominaltop width, WmmNominalheight, TmmNomi
27、nal includedangle, AdegreesWedge beltsSPZ 8.5 10.0 8.0 40SPA 11.0 13.0 10.0 40SPB 14.0 17.0 14.0 40SPC 19.0 22.0 18.0 40V-beltsY 5.3 6.0 4.0 40Z 8.5 10.0 6.0 40A 11.0 13.0 8.0 40B 14.0 17.0 11.0 40C 19.0 22.0 14.0 40D 27.0 32.0 19.0 40NOTE See Figure 1a) and Figure 1b). BSI 2006 3BS 3790:2006Table 2
28、 Banded belts belt spacing3.5 datum widthWdbasic dimension of standardization for the belt and for the corresponding pulley groove, considered as a wholeNOTE 1 See also 3.6.NOTE 2 The term “datum” replaces “pitch” used throughout earlier versions of this standard, but is essentially the same value.
29、The term “datum” brings this standard into line with ISO standards.3.6 pulley groove datum widthWdgwidth of the pulley groove which is dimensionally the same as the datum width of the belt associated with the pulley3.7 relative heightratio of the nominal height of the belt (T) to its datum width (Wd
30、)3.8 datum length of a beltLdcircumferential length of the belt at the datum widthNOTE This is determined by the method specified in 4.4.3.9 nominal height of a beltTheight of the trapezium outlined on a cross-section of the beltNOTE See Figure 1a) and Figure 1b).3.10 nominal top width of a beltWlar
31、ger width of the trapezium outlined on a cross-section of the beltNOTE See Figure 1a) and Figure 1b).3.11 angle of a beltAincluded angle obtained by extending the sides of the beltNOTE See Figure 1a) and Figure 1b).3.12 pulley datum diameterdd or Dddiameter of the pulley measured at the groove datum
32、 widthBelt sectionon bandBeltspacing,ebmmTol., A)ebTol., B)CebBelt sectionon bandBeltspacing,ebmmTol., A)ebTol., B)ebSPZ 12.0 0.25 0.5 A (RMA only) C)15.88 0.3 0.6SPA 15.0 0.30 0.6 B 19.0 0.4 0.8SPB 19.0 0.40 0.8 C 25.5 0.5 1.0SPC 25.5 0.40 0.8 D (RMA only) C)0.6 1.2NOTE See Figure 1c).A)Tolerance f
33、or the belt spacing between two adjacent belts.B)Tolerance for the belt spacing over all belts on the band.C)These belts are only suitable for use in pulleys to RMA (USA) standards.36.53BS 3790:20064 BSI 2006 3.13 antistatic beltbelt that conforms to specified maximum electrical resistance requireme
34、ntsNOTE See 4.7.3.14 power ratingmaximum power that a specific belt can transmit under specified geometrical and ambient conditions during a given period of time, provided the drive is installed and maintained following generally accepted rules for V-belt and wedge belt drives and gives a satisfacto
35、ry service life4 Wedge belts, V-belts and banded belts4.1 Materials and workmanshipBelts shall consist of a combination of fabric, cord and elastomeric compound(s), the whole being bonded together in a uniform manner and shaped in accordance with the best manufacturing practice. Belts shall be suita
36、ble for operating at ambient temperatures between 18 C and +60 C and shall not be adversely affected by the temperature under normal operating conditions within this range.4.2 ConstructionThe construction of the belt shall be one of four basic belt constructions as illustrated in Figure 2. BSI 2006
37、5BS 3790:20064.3 Cross-sectional dimensionsThe nominal cross-sectional dimensions and the nominal included angle of belts shall be as given in Table 1; however, dimensions of belts made by individual manufacturers may vary slightly from the nominal values given in Table 1, provided that the belts fi
38、t pulley grooves within the limits given in Table 3 when mounted on two measuring pulleys made in accordance with Table 4.Figure 2 Basic belt constructiona) Wrapped belt b) Raw edge plain beltc) Raw edge cogged belt d) Raw edge laminated beltKey1Wrapping fabric2Top fabric3Top cushion4Tie gum5 Tensio
39、n member6 Bottom cushion7 Bottom fabric8 Fabric laminationNOTE Any of these belt constructions can be used as a banded belt1345623456723456234568BS 3790:20066 BSI 2006 4.4 Belt datum lengthWhen determined in accordance with Annex A, the belt datum length and datum length variation shall be as given
40、in Table 5.Table 3 Tolerances and force requirements when measuring new beltsCross-section symbol Total force applied to belt, FNPosition of top face of belt with respect to top of grooveMaximummmMinimummmWedge beltsSPZ 360 +1.1 0.4SPA 560 +1.3 0.6SPB 900 +1.4 0.7SPC 1 500 +1.5 1.0V-beltsY 40 +0.8 0
41、.8Z 110+1.6 1.6A 2 B 3 C 750+1.5 2.0D1 4 6 3Table 4 Dimensions of pulleys for measuring lengths of new beltsDimensions in millimetresCross-section symbol A)Datum width,WdNominal datum diameter,DdNominal pulley circum-ference at datum diameterOutsidediameterTop width of groove,gMinimum groove depth,d
42、Groove angle,AWedge beltsSPZ/XPZ 8.5 95.5 300 99.76 9.91 11.0 38 0.25SPA/XPA 11.0 143.2 450 149.13 12.96 14.0 38 0.25SPB/XPB 14.0 191.0 600 198.29 16.45 17.5 38 0.25SPC/XPC 19.0 318.3 1 000 328.26 22.35 23.8 38 0.25V-beltsY/YX 5.3 28.7 90 32.13 6.24 6.3 32 0.25Z/ZX 8.5 57.3 180 62.60 10.06 9.5 34 0.
43、25A/AX 11.0 95.5 300 102.42 13.05 12.0 34 0.25B/BX 14.0 127.3 400 136.08 16.61 15.0 34 0.25C/CX 19.0 222.8 700 234.62 22.53 20.0 34 0.25D/DX 27.0 318.3 1 000 334.97 32.32 28.0 36 0.25NOTE 1 See Annex A.NOTE 2 The outside diameter of the pulleys include tolerances in order to make it simpler to manuf
44、acture the pulleys, however the key diameter for length identification and drive design is the datum diameter (D ).A)Descriptions of cross-section symbols are included in Table C.2.0.000.06+0.000.03+0.000.06+0.000.03+0.000.06+0.000.03+0.000.06+0.000.03+0.000.06+0.000.03+0.000.06+0.000.03+0.000.06+0.
45、000.03+0.000.06+0.000.03+0.000.06+0.000.03+0.000.06+0.000.03+d BSI 2006 7BS 3790:2006Table 5 Nominal datum lengths of wedge belts and V-belts and permitted tolerancesDimensions in millimetresDatum length rangeNominal datum lengths Maximum datum length variationWedge belts V-belts Non-matched setsMat
46、ched setsSPZ SPA SPB SPC Y Z A B C D200to399200224250280315355+842400to529400450500405475+106530to7096305306257006307007710to899710800 800780 7908909900to1 2499001 0001 1209001 0001 1209201 0809901 1009301 0001 1001 210131 250to1 5991 2501 4001 2501 4001 2501 4001 6001 2501 4301 5501 3701 560 1 5601
47、61 600to1 8991 6001 8001 6001 800 1 800 1 7501 6901 760 1 760191 900to2 2492 000 2 0002 2402 0002 0002 2401 9402 0502 2001 9502 1801 9502 19023 42 250to2 7992 2402 500 2 5002 2402 500 2 5002 3002 4802 5702 7002 3002 5002 7002 3402 4902 720 2 740282 800to3 1492 800 2 800 2 800 2 800 2 9103 0802 870 2
48、 8803 080 3 130313 150to3 6993 1503 5503 1503 5503 1503 5503 1503 5503 2903 5403 2003 6003 3103 5203 330 37 63 700to4 9994 0004 5004 0004 5004 0004 5004 0604 4304 8204 0604 6003 7304 0804 620505 000to5 9995 0005 6005 0005 600 5 370 5 380 5 40060 86 000to6 9996 300 6 300 6 070 6 1006 8606 1006 840707
49、 000to8 9997 1008 0007 1008 0007 600 7 6208 410909 000to9 9999 000 9 100 9 140 100 1210 000to12 49910 00011 20010 700 10 70012 20012512 500to16 00012 500 13 70015 200160 14BS 3790:20068 BSI 2006 4.5 Matched beltsIn order to avoid uneven distribution of load, belts running on a multi-belt drive shall be matched belts and their lengths shall be within the tolerances given for m
