AGMA ISO 22849-A12-2012 Design Recommendations for Bevel Gears.pdf

1、AGMA ISO 22849-A12Identical to ISO/TR 22849:2011AGMA Information SheetDesign Recommendations forBevel GearsAGMAISO22849-A12iiDesign Recommendations for Bevel GearsAGMA ISO 22849-A12Identical to ISO/TR 22849:2011CAUTIONNOTICE: AGMA technical publications are subject to constant improvement,revision o

2、r withdrawal as dictated by experience. Any person who refers to any AGMAtechnicalpublicationshouldbesurethatthepublicationisthelatestavailablefromtheAs-sociation on the subject matter.Tablesorotherself-supportingsectionsmaybereferenced. Citationsshouldread: SeeAGMA ISO 22849-A12, Design Recommendat

3、ions for Bevel Gears, published by theAmericanGearManufacturersAssociation,1001N.FairfaxStreet,Suite500,Alexandria,Virginia 22314, http:/www.agma.org.Approved May 7, 2012ABSTRACTThisinformationsheetdiscussestheapplicationofbevelandhypoidgearsusingthegeometryinANSI/AGMAISO 23509, the capacity as dete

4、rmined by ISO 10300 (all parts), or ANSI/AGMA 2003-C10 and AGMA932-A05,andthetolerancesinANSI/AGMAISO17485. Itprovidesadditional informationon theapplication,manufacturing,strengthandefficiencyofbevelgearsforconsiderationinthedesignstageofanewbevelgearset.Published byAmerican Gear Manufacturers Asso

5、ciation100 N. Fairfax Street, Suite 500, Alexandria, Virginia 22314Copyright 2012 by American Gear Manufacturers AssociationAll rights reserved.No part of this publication may be reproduced in any form, in an electronicretrieval system or otherwise, without prior written permission of the publisher.

6、Printed in the United States of AmericaISBN: 978-1-61481-029-2AmericanGearManufacturersAssociationAGMA ISO 22849-A12AMERICAN GEAR MANUFACTURERS ASSOCIATIONiii AGMA 2012 All rights reservedContentsPageForeword vi.1 Scope 1.2 Symbols, descriptions and units 13 Application 2.3.1 Geometry 2.3.2 Rating 3

7、3.2.1 General 33.2.2 Bending strength 33.2.3 Pitting resistance 33.2.4 Other forms of bevel gear tooth deterioration 33.3 Materials 3.3.4 Gear tolerances 3.3.5 Gear noise 43.5.1 General 43.5.2 Tooth flank form corrections 4.3.5.3 Design contact ratio 43.5.4 Other noise consideration 6.4 Manufacturin

8、g consideration 7.4.1 Outline of production methods and their features face milling and face hobbing 74.2 Blank design and tolerances 84.2.1 General aspects 8.4.2.2 Clamping surface 84.2.3 Tooth backing 9.4.2.4 Load direction 9.4.2.5 Locating surface 9.4.2.6 Solid shanks 94.2.7 Flanged hub 104.2.8 S

9、plined bores 10.4.2.9 Ring-type designs 114.2.10 Dowel 124.2.11 Hub projections 12.4.2.12 Blank tolerances 13.4.2.13 Drawing specifications for blanks 164.3 Assembly 16.4.3.1 General 164.3.2 Correct assembly 164.3.3 Markings 16.4.3.4 Positioning bevel gears 18.4.3.5 Backlash measurement 18.4.3.6 Amo

10、unt of axial movement for a limited change in backlash 19.4.3.7 Endplay 204.4 Tooth contact pattern 20.4.4.1 General 204.4.2 Typical contact patterns 214.4.3 Need for position control 224.4.4 Deflection tests 224.4.5 Drawing specifications 225 Strength considerations 22AGMA ISO 22849-A12 AMERICAN GE

11、AR MANUFACTURERS ASSOCIATIONiv AGMA 2012 All rights reserved5.1 Effect of hypoid offset 225.2 Effect of cutter radius 22.5.3 Bevel gear mountings 235.4 Direction of forces 25.6 Efficiency considerations 25.6.1 Hypoid and bevel gear mesh efficiency 25.6.1.1 General 256.1.2 Gear efficiency 266.1.3 Eff

12、iciency of mesh 26.6.1.4 Profile sliding 266.1.5 Hypoid lengthwise sliding 27.6.1.6 Coefficient of friction 28.6.1.7 Churning efficiency 286.2 Lubrication 296.2.1 Principles for lubrication 296.2.2 Selection criteria of lubricants 29.6.2.3 Types of lubricants 30.6.2.4 Application of lubricant 31.Bib

13、liography 33.Figures1 Example of a gear pair finished by lapping process 52 Effect of profile crowning and flank twist on transmission error lengthwise crowning of 20 mm6.3 The effect of design contact ratio on transmission error 74 Recommended clamping surface of the blank 8.5 Tooth backing 96 Webl

14、ess mitre gear counterbored type 97 Suggested locating surfaces 10.8 Shank-type pinion with tapped hole 10.9 Shank-type pinion with external threads 10.10 Spline mounting 11.11 Typical wheels mounted on hubs 11.12 Methods of mounting gear 12.13 Example of required cutter clearance 1314 Method 1 for

15、specifying blank tolerances on bevel gears 14.15 Method 2 for specifying blank tolerances on bevel gears 15.16 Typical gear markings 16.17 Measurement of normal backlash 17.18 Bevel gear backlash Normal and transverse 19.19 Influence of axial movement on backlash 20.20 Typical non-loaded contact pat

16、terns 21.21 Calculated loaded contact pattern 22.22 Size of cutter radius 23.23 Direction of tooth bearing shift caused by misalignment 2324 Position of axes in bevel gearing 2425 Typical mounting arrangements 25.26 Typical gear tooth forces 26.AGMA ISO 22849-A12AMERICAN GEAR MANUFACTURERS ASSOCIATI

17、ONv AGMA 2012 All rights reservedTables1 Symbols, terms and definitions 1.2 Typical values of transmission error 4.3 Face angle and back angle distance tolerances 14.4 Suggested tolerances for bore or shank diameter 14.5 Suggested tolerances for blank dimensions 156 Suggested normal backlash toleran

18、ce at tightest point of mesh 197 Effect of cutter radius in the tooth bearing shift caused by misalignment 248 Recommended positional tolerances of axes 24.9 Typical oil jet location 32AGMA ISO 22849-A12 AMERICAN GEAR MANUFACTURERS ASSOCIATIONvi AGMA 2012 All rights reservedForewordTheforeword,footn

19、otesandannexes,ifany,inthisdocumentareprovidedforinformationalpurposesonlyandare not to be construed as a part of AGMA ISO 22849-A12, Design Recommendations for Bevel Gears.The U.S. delegation proposed development of a new standard to ISO Technical Committee 60 on bevel geargeometry and associated d

20、esign recommendations based on ANSI/AGMA 2005-D03, Design Manual forBevel Gears. It was decided to address this project through the preparation of 1) an International Standardfocusing strictly on bevel geometry (ISO 23509:2006, Bevel and hypoid gear geometry), and 2) acomplimentary ISO Technical Rep

21、ort (ISO/TR 22849:2011, Design recommendations for bevel gears)whichwould present other design issues to be considered.ISO 23509 was adopted as an American National Standard, ANSI/AGMA ISO 23509-A08, in 2008.Information Sheet AGMA ISO 22849-A12 represents an identical adoption of ISO/TR 22849:2011 w

22、ith thefollowing revisions/clarifications:- in 3.2.4, the term “case crushing” waschanged to the preferredterm “subcasefatigue” and“welding” tothepreferred term “scuffing”;- in 6.2.3.2.2, the numerator of equation (44) was revised to the correct value of 500;- recommendationtouseAGMAdocumentsforload

23、capacitycalculationsinadditiontoISO10300wasmade;- reference wasmade to those ISOstandardsand technical reportsthathavebeen adoptedbyAGMAusingtheir appropriate document numbers.ThefirstdraftofAGMAISO22849-A12wasmadeinMay,2011. ItwasapprovedbytheAGMAmembershiponMay 7, 2012.Suggestions for improvement

24、of this document will be welcome. They should be sent to the American GearManufacturers Association, 1001 N. Fairfax Street, Suite 500, Alexandria, Virginia 22314.AGMA ISO 22849-A12AMERICAN GEAR MANUFACTURERS ASSOCIATIONvii AGMA 2012 All rights reservedPERSONNEL of the AGMA Bevel Gearing CommitteeCh

25、airman: Robert F. Wasilewski Arrow Gear Company.Vice Chairman: George Lian Amarillo Gear Company LLCACTIVE MEMBERSW. Bradley, III ConsultantS.R. Davidson Boeing Rotorcraft - Philadelphia.D.R. Houser Ohio State University.E.O. Hurtado FLSmidth, Inc.J. Kolonko Rexnord Gear Group.T.J. Krenzer Consultan

26、t, Gleason Works.K. Miller Dana Spicer Off Highway Products.A.A. Swiglo Northern Illinois UniversityW. Tsung Dana Holding Corporation1 AGMA 2012 All rights reservedAGMA ISO 22849-A12AMERICAN GEAR MANUFACTURERS ASSOCIATIONAmerican Gear Manufacturers Association -Design Recommendations for Bevel Gears

27、1 ScopeThisinformationsheetprovidesinformationfortheapplicationofbevelandhypoidgearsusingthegeometryinANSI/AGMA ISO 23509, the capacity as determined by ISO 10300 (all parts), or ANSI/AGMA 2003-C10 andAGMA 932-A05, and the tolerances in ANSI/AGMA ISO 17485.This information sheet provides additional

28、information on the application, manufacturing, strength andefficiency of bevel gears for consideration in the design stage of a new bevel gear set.The term “bevel gear” is used to mean straight, spiral, zerol bevel and hypoid gear designs. Where thisinformation sheet pertains to one or more, but not

29、 all, the specific forms are identified.Themanufacturingprocessofformingthedesiredtoothformisnotintendedtoimplyanyspecificprocess,butrather to be general in nature and applicable to all methods of manufacture.Thisinformationsheetisintendedforusebyanexperiencedgeardesignercapableofselectingreasonable

30、val-uesfortherequireddatabasedonhis/herknowledgeandbackground. Itisnotintendedfor usebytheengin-eering public at large.2 Symbols, descriptions and unitsThesymbolsanddescriptionsusedinthisinformationsheetare,whereverpossible,consistentwithotherInter-nationalStandardsonbevelgears. Asaresultofcertainli

31、mitations,somesymbolsanddescriptionsarediffer-ent than in similar literature pertaining to spur and helical gearing. See Table 1.Table 1 - Symbols, terms and definitionsSymbol Description UnitsAgArrangement constant - -avCenter distance of virtual cylindrical gears mmbeffFace width in contact with m

32、ating element mmC1A constant - -D Outside diameter of the considered rotating element mmdae1, dae2Outside diameter mmdv1, dv2Reference diameter of virtual cylindrical gear mmdva1, dva2Tip diameter of virtual cylindrical gear mmfgGear dip factor - -ham1, ham2Mean addendum mmjenOuter normal backlash m

33、mjetOuter transverse backlash mmK Load intensity for calculating the coefficient of friction N/mm2L Length of the element of the considered rotating element mm(continued)AGMA ISO 22849-A12 AMERICAN GEAR MANUFACTURERS ASSOCIATION2 AGMA 2012 All rights reservedTable 1 (concluded)Symbol Description Uni

34、tsmtTransverse tooth module of the gear considered mmn Rotational shaft speed r/minP Design power kWPGWiPower loss for each individual element kWRfRoughness factor - -Rm1, Rm2Mean cone distance mmTi1, Ti2Input torque per unit force, pinion and wheel mmTo2Output torque, wheel, per unit force mmT1Pini

35、on torque NmtB1, tB2Pinion back angle distance mmtE1, tE2Pinion crown to back mmtF1, tF2Pinion face angle distance mmvetPitch line velocity at outside diameter m/sz1, z2Number of pinion, wheel teeth - -nGenerated pressure angle according to ISO 23509 vat1, vat2Pressure angle at tip of virtual cylind

36、rical gear vtPressure angle in transverse plane of virtual cylindrical gear eOuter spiral angle according to ISO 23509 m1, m2Mean spiral angle vSpiral angle of virtual cylindrical gear t1, t2Change in pressure angle from pitch point to outside a1, a2Face angle 1, 2Pitch angle PGWSum of power losses

37、regarding churning kW Friction angle ffcSum of element churning efficiency (see 6.1.6) - -fflLengthwise sliding efficiency (see 6.1.5) - -ffpProfile sliding efficiency (see 6.1.4) - -mmCoefficient of friction (see 6.1.6) - -, Kinematic oil viscosity at operating temperature, kinematic viscosity at40

38、 Cmm2/s (cSt)3 Application3.1 GeometryFor the purposes of this information sheet, the geometry of bevel and hypoid gear pairs is assumed to becalculatedaccordingtoANSI/AGMAISO23509. Thesecalculationsneedatleastasetofinitialdata. Ifthesedataarenotcompletelygivenorknownfromsimilarapplications,aroughes

39、timateofthegeardimensionscanbe determined by means of the power to be transmitted (see Annex B of ANSI/AGMA ISO 23509-A08).Inanycase,acompletegeometrycalculationhastobesuccessfullyexecutedbeforeanyotherofthefollowingconsiderations makes sense.3.2 Rating3.2.1 GeneralTo make a rating of a pair of beve

40、l gears one should have a mathematically correct set of geometry (see 3.1).This enables the designer to proceed to more detailed calculations which complete the design insofar as theAGMA ISO 22849-A12AMERICAN GEAR MANUFACTURERS ASSOCIATION3 AGMA 2012 All rights reservedtransmitted torque is concerne

41、d. Additional rating criteria for bending strength and pitting resistance shouldalso be considered. The method for calculating the bending strength and pitting resistance of bevel gearsexcept hypoid gears is stated in ISO 10300 (all parts), or ANSI/AGMA 2003-C10. See AGMA 932-A05 forhypoid gears.3.2

42、.2 Bending strengthBendingstrengthasacriterionofbevelandhypoidgearcapacitycanbedefinedastheabilityofthegearsettowithstand repeated or continued operation under nominal load without fracture of the teeth in their roots byfatigueinbending. Itisafunctionofthebending(tensile)stressesinacantileverbeamand

43、isproportionaltotheapplied load. It also involves the fatigue strength of the gear materials and the shape of the teeth. Therefore,either the pinion or the wheel can be the limiting member of the pair.3.2.3 Pitting resistancePittingresistanceasacriterionofbevelandhypoidgearcapacitycanbedefinedasthea

44、bilityofthegearsettowithstandrepeatedorcontinuedoperationundernominalloadwithoutsufferingdestructivepittingofthetoothsurfaces. The experienced gear designer recognizes that moderate, non-destructive pitting of the tooth sur-facescanoccurduringtheearlystagesofoperation,especiallyonnon-hardenedorthrou

45、gh-hardenedgears.In these cases, the pitting ceases to progress after the asperities have been removed by the initial operation.This process, called initial pitting, should not affect the gear life.Destructivepitting,althoughattributableinprincipletothesamephenomena,progresseswidelyenoughtodes-troy

46、the geometry of the flank surfaces and ultimately leads to failure. The distinction between initial anddestructive pitting is defined more thoroughly in ISO 10825 or ANSI/AGMA 1010-E95.Pittingisafunctionofseveralfactors;themostsignificantisHertziancontact(compressive)stressesbetweenthetwomatingtooth

47、surfacesandisproportionaltothesquarerootoftheappliedtoothload. Theabilityofbevelandhypoidgearteethtowithstandrepeatedsurfacecontactunderloadwithoutdestructivepittinginvolvestheresistance of the gear material to fatigue under contact stresses. The smaller gear is usually the limitingmemberofthepairbe

48、causetheteethreceivemorestresscyclesperunittime. Insomecases,thesmallergearis made harder than its mate, to increase its surface durability so that the limiting capacity can exist in eithermember.3.2.4 Other forms of bevel gear tooth deteriorationTheratingstandardsarenotapplicabletoothertypesofgeart

49、oothdeteriorationsuchasmicropitting,subcasefatigue (case crushing), wear, plastic yielding and scuffing (welding).Information on scuffing can be found in ISO/TR 13989-1.3.3 MaterialsThequalityofmaterialsandmethodsofheattreatmentrequiredaregovernedbytheapplication. Careshouldbetakentochoosethepropermaterialforeachapplicationtotransmittheloadandobtainthelifedesired. Heattreatment is usually needed to develop the necessary hardness, strength and wear resistance.F