1、Designation: A291/A291M 16Standard Specification forSteel Forgings, Carbon and Alloy, for Pinions, Gears andShafts for Reduction Gears1This standard is issued under the fixed designation A291/A291M; the number immediately following the designation indicates the yearof original adoption or, in the ca
2、se of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers normalized and tempered car-bon steel and quenched and tempered
3、 alloy steel forgings forpinions, gears, and shafts.1.2 Several grades of steel are covered as follows:1.2.1 Grade 1, Class A, is normalized and tempered carbonsteel.1.2.2 Grade 2, Class B, Grade 3, Class C, Grade 3A, ClassD, Grades 4 to 7, Classes E, F, G, and H, Grade 8, Class I, andGrade 9, Class
4、 J, are liquid quenched and tempered alloy steel.1.3 All grades and classes are considered weldable underproper conditions. Welding technique is of fundamental impor-tance and it is presupposed that welding procedure andinspection shall be in accordance with approved methods forthe class of material
5、 used.1.4 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformanc
6、ewith the standard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to
7、use.2. Referenced Documents2.1 ASTM Standards:2A275/A275M Practice for Magnetic Particle Examination ofSteel ForgingsA388/A388M Practice for Ultrasonic Examination of SteelForgingsA788/A788M Specification for Steel Forgings, General Re-quirements3. Ordering Information3.1 Instructions for purchasing
8、 forgings to this specificationshould be in accordance with Specification A788/A788M.Inaddition, a detailed drawing, sketch, or written description ofthe forging should be included with the inquiry or order.3.2 Supplementary requirements are provided and shallapply only when specified in the purchas
9、e order.4. Heat Treatment4.1 Preliminary Heat Treatment:4.1.1 The forgings shall be given such preliminary heattreatment as is proper for the design and composition. Theforgings shall be heated to a suitable temperature for asufficient length of time for austenitization and shall be suitablycooled t
10、o bring about complete transformation.4.1.2 Forgings may be immediately treated for mechanicalproperties after preliminary heat treatment or may be roughturned prior to treatment for mechanical properties.4.2 Heat Treatment for Mechanical PropertiesThe forg-ing shall be reheated to a temperature abo
11、ve the upper criticaltemperature and held a sufficient length of time for completeaustenitization. Grade 1 shall be air cooled while Grades 2through 9 shall be liquid quenched.4.3 TemperingThe forgings shall be tempered to developthe specified properties. Minimum tempering temperaturesshall be as fo
12、llows:Minimum Tempering TemperatureGrade Class F C1 and 2 A and B 1150 6203, 3A, and 4 C, D, and E 1075 5805, 6, 7 F, G, and H 1050 5658 I 1100 5959 J 1000 540The charge shall be cooled under uniform conditions in thefurnace at a maximum rate of 100F 55C per h to 600F315C.4.4 Stress ReliefIf the man
13、ufacturer elects to heat treat formechanical properties prior to machining, the forgings shall be1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.06 on Steel Forgings and Billets.Curren
14、t edition approved May 1, 2016. Published May 2016. Originallyapproved in 1946. Last previous edition approved in 2015 as A291/A291M 05(2015). DOI: 10.1520/A0291_A0291M-16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For An
15、nual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1stress rel
16、ieved after machining (see 4.5) at a temperature that is50 to 100F 30 to 55C below the last previous temperingtemperature but in no case below 1000F 540C. Theforgings shall be cooled under uniform conditions in thefurnace at a maximum rate of 100F 55C/h to 600F315C.4.5 Machining:4.5.1 Rough machinin
17、g before heat treatment for mechani-cal properties may be performed at the option of the manufac-turer.4.5.2 If the producer elects to heat treat for mechanicalproperties prior to machining, the forgings shall be stressrelieved after machining.4.5.3 BoringForgings, after being heat treated for me-ch
18、anical properties and subsequently bored, shall be stressrelieved.5. General Requirements5.1 Unless otherwise specified herein, the requirements ofSpecification A788/A788M shall apply to forgings supplied tothis specification.6. Chemical Requirements6.1 The steel shall conform to the requirements fo
19、r chemicalcomposition prescribed in Table 1.6.2 The limits for elements other than carbon, manganese,phosphorus, sulfur, and silicon in Grade 2 alloy shall be agreedupon between the manufacturer and purchaser.7. Mechanical Requirements7.1 Tensile and Impact Requirements:7.1.1 The material shall conf
20、orm to the requirements fortensile and impact properties prescribed in Table 2 and impactproperties (see S2) when agreed upon between the purchaserand the supplier.7.1.2 ClassificationThe nominal or specified rough-machined diameter or thickness of solid forgings, disregardinglarge ends, collars and
21、 flanges, or the nominal rough-machinedwall thickness of bored forgings shall determine the sizeclassification.7.1.3 Number, Location, and Orientation of Test Specimens:7.1.3.1 At least one tension test specimen either longitudinalor tangential at the option of the manufacturer shall be takenfrom ea
22、ch forging unless a number of forgings are forged andtreated in multiple, in which case one tension test specimenshall be taken from each end of the multiple forging. Whenimpact tests are specified in accordance with SupplementaryRequirement S2, one set of impact tests shall also be takenfrom each e
23、nd of the multiple forging. When agreed uponbetween the manufacturer and the purchaser, forgings weigh-ing less than 500 lb 225 kg each (rough-machined weight)may be tested in lots; the number of forgings to make up a lotshall be by mutual agreement.7.1.3.2 Tension and impact test specimens shall be
24、 takenfrom an extension of the main body of the forging, or from afull-size prolongation left on one end of each individualforging or on both ends of the multiple forging if the forgingsare made in multiple. The nominal or specified outside rough-machined diameter or thickness of the forgings, disre
25、gardinglarge ends, collars and flanges, shall determine the size ofprolongations for test specimens.7.1.3.3 The axis of the longitudinal tension test specimenshall be located at any point 114 in. 32 mm below the surfaceof the forging. The axis of the tangential test specimen shall belocated as near
26、to the surface of the forging as practicable.7.2 Brinell Hardness:7.2.1 The material shall conform to the requirements forhardness as prescribed in Table 2. Brinell hardness tests shallbe made on prepared areas on the forgings after machining tothe sizes ordered by the purchaser and after stress rel
27、ieving ifstress relieving is required.7.2.2 Number and Location of TestsOn each forging 8 in.200 mm and over in diameter, four Brinell hardness testsshall be made on the outside surface of that portion of theforging on which teeth will be cut, two tests being made oneach end 180 apart and the tests
28、on the two ends shall be 90apart. On each forging under 8 in. 200 mm in diameter, twoBrinell hardness tests shall be made, one on each end 180apart. On shaft forgings, two hardness tests shall be made oneach end 180 apart.TABLE 1 Chemical RequirementsElement Composition, %Grade 1 Grade 2 Grade 3 Gra
29、de 3A Grades 4 to 7 Grade 8 Grade 9Class A Class B Class C Class DClasses E, F, G,and H Class I Class JCarbon 0.55 max 0.50 max 0.45 max 0.45 max 0.350.50 0.380.45 0.250.39Manganese 0.600.90 0.400.90 0.400.90 0.400.90 0.400.90 0.400.70 0.200.60Phosphorus, max 0.040 0.040 0.040 0.040 0.040 0.040 0.01
30、5Sulfur, max 0.040 0.040 0.040 0.040 0.040 0.040 0.015SiliconA, max 0.35 0.35 0.35 0.35 0.35 0.40 0.35Nickel 0.30 maxB0.50 max 1.003.00 1.65 min 0.30 max 3.254.00Chromium 0.25 maxB1.25 max 1.50 max 0.60 min 1.401.80 1.251.75Molybdenum 0.10 maxB0.15 min 0.15 min 0.200.60 0.300.45 0.300.70Vanadium, ma
31、x 0.06 0.10 0.05 0.10 0.10 0.03 0.050.15Copper, max 0.35 0.35 0.35 0.35 0.35 0.35 0.35Aluminum . . . . . . . . . . . . . . . 0.851.30 . . .AWhen vacuum carbon deoxidation is used, silicon maximum shall be 0.10 %.BOptional with manufacturer and purchaser.A291/A291M 1628. Retreatment8.1 If the results
32、 of the mechanical tests of any forging donot conform to the specified requirements, the manufacturermay retreat the forging one or more times, but not more thanthree additional times without approval of the purchaser.9. Dimensions and Tolerance9.1 The forgings shall conform to the dimensions andtol
33、erances specified on the purchasers drawing or order.10. Certification and Reports10.1 Material test reports as specified in Specification A788/A788M are required and shall include the final austenitizingand tempering temperatures, holding times, and methods ofcooling.11. Marking, Packaging, and Loa
34、ding11.1 Each forging shall be legibly stamped by the manufac-turer with the manufacturers name or trademark, the manu-facturers serial number, ASTM designation A291/A291M,followed by the appropriate class number. The purchaser mayindicate the desired location of such identification information.11.2
35、 Packaging and loading shall be done so the forging isnot damaged during shipment to the purchaser.12. Keywords12.1 alloy steel forgings; carbon steel forgings; gear forg-ings; gear shaft forgings; heat-treated; pinion forgingsSUPPLEMENTARY REQUIREMENTSThe following supplementary requirements shall
36、apply only when specified by the purchaser on theorder and agreed to by the manufacturer.S1. Rough Turning and BoringS1.1 The position of rough turning and boring in thesequence of manufacturing operations is specified.S2. Impact TestsS2.1 Impact tests shall be made. The specimens shall bemachined a
37、nd tested with minimum properties and test tem-peratures specified as follows.Charpy V-Notch, ftlbf J, 70 to 80F20 to 25C minGrade Class Longitudinal Transverse (Tangential)1 A 10 13 8 112 B 10 13 8 113 C 30 40 20 273A D 30 40 20 27TABLE 2 Mechanical PropertiesGrade ClassSize, SolidDiameter orThickn
38、ess, in.ATensile Strength, minYield Strength, 0.2%Offset, minElongation in 2 in. 50mm, min, %Reduction of Area,min, %CharpyV-notchFtlb JBrinellHardnessNumberRangeOverNotOver ksi MPa ksi MPaLongi-tudinalTransverse(Tangential)Longi-tudinalTransverse(Tangential)1 A .1010.858058555050453453102220.164537
39、.30. . . 170 - 2232 B .10201020.959595655655655707070485485485202018.1816454538.3430. . . 201 - 2413, 3A C, D .10201020.105105105725725725808080550550550191918.1614454538.3230. . . 223 - 2624 E .10201020.120120115825825795959590655655620161413.1210403533.3025. . . 248 - 2935 F .10201020.140135130965
40、930905115110105795760725161412.1210403530.3025. . . 285 - 3316 G .10201020.1451401351000965930120115110825795760151412.1210403530.3025. . . 302 - 3527 H .10201020.170165160137511401105140135130960930905141210.1010353025.2525. . . 341 - 4158 I . 10 120 825 85 585 15 . 40 . 255 - 3029 J 20 . . . 170 1
41、175 140 960 10 10 30 30 25 30 352 - 401A10 in. = 250 mm. 20 in. = 500 mm.A291/A291M 163Charpy V-Notch, ftlbf J, 70 to 80F20 to 25C minGrade Class Longitudinal Transverse (Tangential)4 E 30 40 20 275 F 25 34 15 206 G 25 34 15 207 H 20 27 10 138 I 811 .S3. Nondestructive ExaminationS3.1 Magnetic parti
42、cle examination may be specified inaccordance with Practice A275/A275M.S3.2 Ultrasonic examination may be specified in accordancewith Practice A388/A388M.S4. PhosphorusS4.1 Phosphorus shall not exceed 0.015 %, and sulfur shallnot exceed 0.018 % for all classes.S5. Vacuum DegassingS5.1 The molten ste
43、el shall be vacuum treated prior to, orduring, pouring of the ingot, to remove objectionable gases,particularly hydrogen.S6. Hardness TestingS6.1 Number and Location of TestsOn each forging 8 in.200 mm and over in diameter, four Brinell hardness testsshall be made on the outside surface of that port
44、ion of theforging on which teeth will be cut, two tests being made oneach helix 180 apart and the tests on the two helices shall be90 apart. On each forging under 8 in. 200 mm in diameter,two Brinell hardness tests shall be made, one on each helix180 apart. Hardness tests shall be performed at the q
45、uarter-face width of the tooth portion diameter. On shaft forgings, twohardness tests shall be made on each end 180 apart. When thissupplement is required, the purchaser shall supply detaileddrawings indicating the location of gear teeth, the helix angle,and the location of the required hardness tes
46、ts.APPENDIX(Nonmandatory Information)X1. PREVIOUS CLASSES AND CORRESPONDING CURRENT GRADESPrevious Class Current Grade Current ClassClass 1 Grade 1 Class AClass 2 Grade 2 Class BClass 3 Grade 3 Class CClass 3A Grade 3A Class DClass 4 Grade 4 Class EClass 5 Grade 5 Class FClass 6 Grade 6 Class GClass
47、 7 Grade 7 Class HClass 8 Grade 8 Class IClass 9 Grade 9 Class JSUMMARY OF CHANGESCommittee A01 has identified the location of selected changes to this standard since the last issue(A291/A291M-05(2015) that may impact the use of this standard. (Approved May 1, 2016.)(1) Revised 7.2.2 to apply to all
48、 forgings when tooth location isnot known. Moved requirements for hardness testing of helicalgears to Supplementary Requirement S6 and added the require-ment that when S6 is invoked detailed drawings be provided tothe manufacturer so that hardness tests can be correctlypositioned.A291/A291M 164ASTM
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