ISO INTERNATIONAL STANDARD 6336-1 Third edition 2019-11 Calculation of load capacity of spur and helical gears - Part 1: Basic principles, introduction and general influence factors Calcul de la capacité de charge des engrenages cylindriques a dentures droite et helicoidale - Partie 1: Principes de base, introduction et facteurs généraux d'influence Reference number ISO 6336-1:2019(E) ISO @ IS0 2019 IS0 6336-1:2019(E) COPYRIGHTPROTECTEDDOCUMENT @ IS0 2019 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may below or Iso's member body in the country of the requester. ISO copyright office CP 401 : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +41 22 749 01 11 Fax: +41 22 749 09 47 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0 2019 - All rights reserved IS0 6336-1:2019(E) Contents Page Foreword ..vi Introduction ..vii 1 Scope. 2 Normative references 3 Terms, definitions, symbols and abbreviated terms ..2 3.1 Terms and definitions. .2 3.2 Symbols and abbreviated terms. 4 Basic principles. .11 4.1 Application .11 4.1.1 Surface durability (pitting) .11 4.1.2 Tooth bending strength .11 4.1.3 Tooth flank fracture. .12 4.1.4 Strength and quality of materials ..12 4.1.5 Service life under variable load. ..12 4.1.6 Scuffing. .12 4.1.7 Wear. .12 4.1.8 Micropitting .12 4.1.9 Plastic-yielding .12 4.1.10 Specific applications .12 4.1.11 Safetyfactors .13 4.1.12 Testing .15 4.1.13 Manufacturing tolerances .15 4.1.14 Implied accuracy. .15 4.1.15 Other considerations. .15 4.1.16 Influence factors. .16 4.1.17 Numerical formulae .18 4.1.18 Succession of factors in the course of calculation .18 4.1.19 Determination of allowable values of gear deviations ..18 4.2 Tangential load, torque and power. .18 4.2.1 General. .18 4.2.2 Nominal tangential load, nominal torque and nominal power. .19 4.2.3 Equivalent tangential load, equivalent torque and equivalent power .19 4.2.4 Maximum tangential load, maximum torque and maximal power .19 5 Application factor, KA .19 5.1 General .19 5.2 Method A Factor KA-A .20 5.2.1 Factor KA-A .20 5.2.2 Factor KHA-A for pitting along ISO 6336-2 20 5.2.3 20 5.2.4 20 5.2.5 .21 5.2.6 .21 5.3 Method B - _Factor KA-B .21 5.3.1 General. .21 5.3.2 Guide values for application factor, KA-B .21 6 Internal dynamic factor, Ky .24 6.1 General .24 6.2 Parameters affecting internal dynamic load and calculations .24 6.2.1 Design .24 6.2.2 Manufacturing. .24 6.2.3 Transmission perturbance .25 6.2.4 Dynamic response.. .25 @ IS0 2019 - All rights reserved iii IS0 6336-1:2019(E) 6.2.5 Resonances 25 6.2.6 Application of internal dynamic factor for low loaded gears 26 6.3 Principles and assumptions. 26 6.4 Methods for determination of dynamic factor 27 Method A- Factor Kv-A 6.4.1 27 Method B- Factor Kv-B 6.4.2 27 6.4.3 27 6.5 Determination of dynamic factor using Method B: Ky-B 28 6.5.1 General. 28 6.5.2 Running speed ranges. 28 6.5.3 Determination of resonance running speed (main resonance) of a gear pair 29 6.5.4 Dynamic factor in subcritical range (N ≤ Ns) 31 6.5.5 Dynamic factor in main resonance range (Ns < N ≤ 1,15) 34 6.5.6 Dynamic factor in supercritical range (N ≥ 1,5) 34 6.5.7 Dynamic factor in intermediate range (1,15 < N < 1,5) 34 6.5.8 Resonance speed determination for specific gear designs 35 6.5.9 Calculation of reduced mass of gear pair with external teeth .37 6.6 Determination of dynamic factor using Method C: Kv-c 38 6.6.1 General. 38 6.6.2 Graphical values of dynamic factor using Method C .39 6.6.3 Determination by calculation of dynamic factor using Method C 42 Face load factors, Kg and Kpg 43 7.1 Geartoothloaddistribution 43 7.2 General principles for determination of face load factors, Khg and Ke 43 7.2.1 General. 43 7.2.2 Face load factor for contact stress, Khp 44 7.2.3 Face load factor for tooth root stress,'Kpβ 44 7.3 Methods for determination of face load factor 'Principles, assumptions 44 7.3.1 Gen