1、BRITISH STANDARD BS ISO 9085:2002 Calculation of load capacity of spur and helical gears Application for industrial gears ICS 21.200 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBS ISO 9085:2002 This British Standard, having been prepared under the direction of the Engineeri
2、ng Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 25 March 2002 BSI 25 March 2002 ISBN 0 580 39231 7 National foreword This British Standard reproduces verbatim ISO 9085:2002 and implements it as the UK national standard. The
3、 UK participation in its preparation was entrusted to Technical Committee MCE/5, Gears, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European
4、 publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessar
5、y provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any en
6、quiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii to vi, pages
7、1 to 57 and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments Reference number ISO 9085:2002(E)INTERNATIONAL STANDARD ISO 9085 First edition 2002-02-01 Calculation of load capacity o
8、f spur and helical gears Application for industrial gears Calcul de la capacit de charge des engrenages denture droite et hlicodale Application aux engrenages industriels ISO 9085:2002(E) ii ISO 9085:2002(E) iiiContents Page Forewordv Introductionvi 1 Scope 1 2 Normative references1 3 Terms and defi
9、nitions .2 4 Application .8 4.1 Design, specific applications .8 4.2 Safety factors .10 4.3 Input data11 4.4 Face widths 11 4.5 Numerical equations .12 5 Influence factors 12 5.1 General12 5.2 Nominal tangential load, F t , nominal torque, T, nominal power, P .12 5.3 Non-uniform load, non-uniform to
10、rque, non-uniform power 12 5.4 Maximum tangential load, F t max , maximum torque, T max , maximum power, P max .13 5.5 Application factor, K A 13 5.6 Internal Dynamic Factor, K v 13 5.7 Face load factor, K H .17 5.8 Face load factor, K F .23 5.9 Transverse load factors, K H , K F 24 6 Calculation of
11、 surface durability (pitting) .26 6.1 Basic formulae .26 6.2 Single pair tooth contact factors, Z B , Z D .28 6.3 Zone factor, Z H .29 6.4 Elasticity factor, Z E 30 6.5 Contact ratio factor, Z 30 6.6 Helix angle factor, Z .31 6.7 Allowable stress numbers (contact), H lim .31 6.8 Life factor, Z NT 32
12、 6.9 Influences on lubrication film formation, Z L , Z vand Z R .32 6.10 Work hardening factor, Z W 33 6.11 Size factor, Z X .34 6.12 Minimum safety factor (pitting), S H min .34 7 Calculation of tooth bending strength 34 7.1 Basic formulae .34 7.2 Form factor, Y F , and stress correction factor, Y
13、S .36 7.3 Helix angle factor, Y .40 7.4 Tooth-root reference strength, FE .40 7.5 Life Factor, Y NT .41 7.6 Relative notch sensitivity factor, Y rel T 41 7.7 Relative surface factor, Y R rel T .43 7.8 Size factor, Y X .44 ISO 9085:2002(E) iv 7.9 Minimum safety factor (tooth breakage), S F min 44 Ann
14、ex A (normative) Special features of less common gear designs 45 Annex B (normative) Tooth stiffness parameters c and c .48 Annex C (informative) Guide values for application factor, K A 51 Annex D (informative) Guide values for crowning and end relief of teeth of cylindrical gears 54 Bibliography 5
15、7 ISO 9085:2002(E) vForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a s
16、ubject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission
17、(IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an Inte
18、rnational Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent righ
19、ts. International Standard ISO 9085 was prepared by Technical Committee ISO/TC 60, Gears, Subcommittee SC 2, Gear capacity calculation. Annexes A and B form a normative part of this International Standard. Annexes C and D are for information only. ISO 9085:2002(E) vi Introduction Procedures for the
20、calculation of the load capacity of general spur and helical gears with respect to pitting and bending strength appear in ISO 6336-1, ISO 6336-2, ISO 6336-3 and ISO 6336-5. This International Standard is derived from ISO 6336-1, ISO 6336-2 and ISO 6336-3 by the use of specific methods and assumption
21、s which are considered to be applicable to industrial gears. Its application requires the use of allowable stresses and material requirements which are to be found in ISO 6336-5. INTERNATIONAL STANDARD ISO 9085:2002(E)1Calculation of load capacity of spur and helical gears Application for industrial
22、 gears 1 Scope The formulae specified in this International Standard are intended to establish a uniformly acceptable method for calculating the pitting resistance and bending strength capacity of industrial gears with spur or helical teeth. The rating formulae in this International Standard are not
23、 applicable to other types of gear tooth deterioration such as plastic yielding, micropitting, scuffing, case crushing, welding and wear, and are not applicable under vibratory conditions where there may be an unpredictable profile breakdown. The bending strength formulae are applicable to fractures
24、 at the tooth fillet, but are not applicable to fractures on the tooth working profile surfaces, failure of the gear rim, or failures of the gear blank through web and hub. This International Standard does not apply to teeth finished by forging or sintering. It is not applicable to gears which have
25、a poor contact pattern. This International Standard provides a method by which different gear designs can be compared. It is not intended to assure the performance of assembled drive gear systems. Neither is it intended for use by the general engineering public. Instead, it is intended for use by th
26、e experienced gear designer who is capable of selecting reasonable values for the factors in these formulae based on knowledge of similar designs and awareness of the effects of the items discussed. CAUTION The user is cautioned that the calculated results of this International Standard should be co
27、nfirmed by experience. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. How
28、ever, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and
29、 IEC maintain registers of currently valid International Standards. ISO 53:1998, Cylindrical gears for general and heavy engineering Standard basic rack tooth profile ISO 54:1996, Cylindrical gears for general and heavy engineering Modules ISO 1122-1:1998, Vocabulary of gear terms Part 1: Definition
30、s related to geometry ISO 1328-1:1995, Cylindrical gears ISO system of accuracy Part 1: Definitions and allowable values of deviations relevant to corresponding flanks of gear teeth 1)ISO 4287:1997, Geometrical Product Specifications (GPS) Surface texture: Profile method Terms, definitions and surfa
31、ce texture parameters 1) This was corrected and reprinted in 1997. ISO 9085:2002(E) 2 ISO 6336-1:1996, Calculation of load capacity of spur and helical gears Part 1: Basic principles, introduction and general influence factors ISO 6336-2:1996, Calculation of load capacity of spur and helical gears P
32、art 2: Calculation of surface durability (pitting) ISO 6336-3:1996, Calculation of load capacity of spur and helical gears Part 3: Calculation of tooth bending strength ISO 6336-5:1996, Calculation of load capacity of spur and helical gears Part 5: Strength and quality of materials ISO 9084:2000, Ca
33、lculation of load capacity of spur and helical gears Application to high speed gears and gears of similar requirements ISO/TR 10495:1997, Cylindrical gears Calculation of service life under variable loads Conditions for cylindrical gears accordance with ISO 6336 ISO/TR 13593:1999, Enclosed gear driv
34、es for industrial applications 3 Terms and definitions For the purposes of this International Standard, the terms and definitions given in ISO 1122-1 apply. For the symbols, see Table 1. ISO 9085:2002(E) 3Table 1 Symbols and abbreviations used in this International Standard Symbol Description or ter
35、m Unit a centre distance amm b facewidth mm b Bfacewidth of an individual helix of a double helical gear mm b Hfacewidth (pitting) mm b Ffacewidth (tooth root) mm b redreduced facewidth (facewidth minus end reliefs) mm b sweb thickness mm b I(II)length of end relief mm c mean value of mesh stiffness
36、 per unit facewidth N/(mm m) c maximum tooth stiffness of one pair of teeth per unit facewidth (single stiffness) N/(mm m) d a1,2tip diameter of pinion (or wheel) mm d an1,2tip diameter of pinion (or wheel) of virtual spur gear mm d b1,2base diameter of pinion (or wheel) mm d bn1,2base diameter of p
37、inion (or wheel) of virtual spur gear mm d en1,2diameter of circle through outer point of single pair tooth contact of pinion, wheel of virtual spur gear mm d f1,2root diameter of pinion, wheel mm d m1,2diameter at mid-tooth depth of pinion, wheel mm d n1,2reference diameter of pinion, wheel of virt
38、ual spur gear mm d shnominal shaft diameter for bending mm d shiinternal diameter of hollow shaft mm d w1,2pitch diameter of pinion, wheel mm d Nf2diameter of a circle near the tooth-roots, containing the limits of the usable flanks of an internal gear or the larger external gear of a mating gear mm
39、 d 1,2reference diameter of pinion, wheel mm f f effeffective profile form deviation m f fprofile form deviation (the value for the total profile deviation F amay be used alternatively for this, if tolerances complying with ISO 1328-1 are used) m f mahelix deviation due to manufacturing inaccuracies
40、 m f pbtransverse base pitch deviation (the values of f ptmay be used for calculations in accordance with ISO 6336:1996, using tolerances complying with ISO 1328-1) m f pb effeffective transverse base pitch deviation m f shhelix deviation due to elastic deflections m f Htooth alignment deviation (no
41、t including helix form deviation) m g path length of contact mm h tooth depth mm ISO 9085:2002(E) 4 Table 1 (continued) Symbol Description or term Unit h aaddendum mm h a0tool addendum mm h f2dedendum of tooth of an internal gear mm h fPdedendum of basic rack of cylindrical gears mm h Febending mome
42、nt arm for load application at the outer point of single pair tooth contact mm h Nf2dedendum of tooth of an internal gear, containing the limits of the usable flanks of an internal gear or the larger external gear of a mating gear mm l bearing span mm m nnormal module mm m redreduced gear pair mass
43、per unit facewidth referenced to the line of action kg/mm n Eresonance speed min 1n 1,2rotation speed of pinion, wheel min 1p bnnormal base pitch mm p bttransverse base pitch mm pr protuberance of the tool mm q finishing stock allowance mm q snotch parameter s Fn/ 2 F q sTnotch parameter of standard
44、 reference test gear r bbase radius mm s pinion offset from shaft centre line mm s Fntooth-root chord at the critical section mm s Rrim thickness mm s prresidual fillet undercut mm u gear ratio | u | = | z 2 /z 1| W 1 a v circumferential speed (without subscript: at reference circle circumferential
45、speed at working pitch circle) m/s x 1,2profile shift coefficient of pinion, wheel y frunning-in allowance (pitch deviation) m y prunning-in allowance (profile deviation) m y running-in allowance for a gear pair m y running-in allowance (equivalent misalignment) m z nvirtual number of teeth of a hel
46、ical gear z 1,2number of teeth of pinion, wheel a B total facewidth of a double helical gear including the gap mm B frunning-in parameter for determination of constant K B krunning-in parameter for determination of constant K ISO 9085:2002(E) 5Table 1 (continued) Symbol Description or term Unit B pr
47、unning-in parameter for determination of constant K B 1,2constants for determination of F x B *constant for determination of the pinion offset C atip relief m C aytip relief resulting from running-in m C v1,2,3constants for determination of constant K C Bbasic rack factor C Rgear blank factor C crow
48、ning height m C 1.9constants for determination of q s E modulus of elasticity, Youngs modulus N/mm 2E auxiliary value for calculation of Y F F mmean transverse force at the reference cylinder (= F tK AK v ) N F t(nominal) transverse tangential force at reference cylinder N F t maxmaximum transverse
49、tangential force at reference cylinder N F tHdeterminant transverse force at the reference cylinder (= F tK AK vK H ) N F total helix deviation m F xinitial equivalent misalignment (before running-in) m G auxiliary value for calculation of Y F H auxiliary value for calculation of Y F J * 1,2polar moment of inertia per unit face width Kg/mm K constant for determination of K v K vdynamic factor K Aapplication factor K Ftransverse load factor (root st
