1、Designation: A291/A291M 16A291/A291M 16aStandard 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
2、 or, in the case 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 carbon steel and quenched
3、 and tempered alloy steel forgings for pinions,gears, and shafts.1.2 Several grades of steel are covered as follows:1.2.1 Grade 1, Class A, is normalized and tempered carbon steel.1.2.2 Grade 2, Class B, Grade 3, Class C, Grade 3A, Class D, Grades 4 to 7, Classes E, F, G, and H, Grade 8, Class I, an
4、dGrade 9, Class J, are liquid quenched and tempered alloy steel.1.3 All grades and classes are considered weldable under proper conditions. Welding technique is of fundamental importanceand it is presupposed that welding procedure and inspection shall be in accordance with approved methods for the c
5、lass of materialused.1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from thetwo systems may result
6、in non-conformance with the standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimit
7、ations prior to use.2. Referenced Documents2.1 ASTM Standards:2A275/A275M Practice for Magnetic Particle Examination of Steel ForgingsA388/A388M Practice for Ultrasonic Examination of Steel ForgingsA788/A788M Specification for Steel Forgings, General Requirements3. Terminology3.1 Definitions:3.1.1 g
8、earsrings, disks, cylinders or rectangular bars having gear teeth.3.1.2 pinionscircular cross section forgings of multiple diameter with gear teeth on one or more diameters.3.1.3 shaftscircular cross section forgings of one or more diameters which do not have integral gear teeth.4. Ordering Informat
9、ion4.1 Instructions for purchasing forgings to this specification should be in accordance with Specification A788/A788M. Inaddition, a detailed drawing, sketch, or written description of the forging should be included with the inquiry or order.4.2 Supplementary requirements are provided and shall ap
10、ply only when specified in the purchase order.1 This specification is under the jurisdiction ofASTM Committee A01 on Steel, Stainless Steel and RelatedAlloys and is the direct responsibility of Subcommittee A01.06on Steel Forgings and Billets.Current edition approved May 1, 2016Dec. 1, 2016. Publish
11、ed May 2016December 2016. Originally approved in 1946. Last previous edition approved in 20152016 asA291/A291M 05A291/A291M 16.(2015). DOI: 10.1520/A0291_A0291M-16.10.1520/A0291_A0291M-16A.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at service
12、astm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Bec
13、auseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appe
14、ars at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Heat Treatment5.1 Preliminary Heat Treatment:5.1.1 The forgings shall be given such preliminary heat treatment as is proper for the design and compositi
15、on. The forgings shallbe heated to a suitable temperature for a sufficient length of time for austenitization and shall be suitably cooled to bring aboutcomplete transformation.5.1.2 Forgings may be immediately treated for mechanical properties after preliminary heat treatment or may be rough turned
16、prior to treatment for mechanical properties.5.2 Heat Treatment for Mechanical PropertiesThe forging shall be reheated to a temperature above the upper criticaltemperature and held a sufficient length of time for complete austenitization. Grade 1 shall be air cooled while Grades 2 through9 shall be
17、liquid quenched.5.3 TemperingThe forgings shall be tempered to develop the specified properties. Minimum tempering temperatures shall beas follows: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 540
18、The charge shall be cooled under uniform conditions in the furnace at a maximum rate of 100F 55C100 F 55 C per h to600F 315C.600 F 315 C.5.4 Stress ReliefIf the manufacturer elects to heat treat for mechanical properties prior to machining, the forgings shall bestress relieved after machining (see 4
19、.55.5) at a temperature that is 50 to 100F100 F 30 to 55C55 C below the last previoustempering temperature but in no case below 1000F 540C.1000 F 540 C. The forgings shall be cooled under uniformconditions in the furnace at a maximum rate of 100F 55C/h100 F 55 Ch to 600F 315C.600 F 315 C.5.5 Machini
20、ng:5.5.1 Rough machining before heat treatment for mechanical properties may be performed at the option of the manufacturer.5.5.2 If the producer elects to heat treat for mechanical properties prior to machining, the forgings shall be stress relieved aftermachining.5.5.3 BoringForgings, after being
21、heat treated for mechanical properties and subsequently bored, shall be stress relieved.6. General Requirements6.1 Unless otherwise specified herein, the requirements of Specification A788/A788M shall apply to forgings supplied to thisspecification.7. Chemical Requirements7.1 The steel shall conform
22、 to the requirements for chemical composition prescribed in Table 1.7.2 The limits for elements other than carbon, manganese, phosphorus, sulfur, and silicon in Grade 2 alloy shall be agreed uponbetween the manufacturer and purchaser.TABLE 1 Chemical RequirementsElement Composition, %Grade 1 Grade 2
23、 Grade 3 Grade 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 0.04
24、0 0.040 0.015Sulfur, 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 max B 0.50 max 1.003.00 1.65 min 0.30 max 3.254.00Chromium 0.25 max B 1.25 max 1.50 max 0.60 min 1.401.80 1.251.75Molybdenum 0.10 max B 0.15 min 0.15 min 0.200.60 0.300.45 0
25、.300.70Vanadium, max 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 . . .A When vacuum carbon deoxidation is used, silicon maximum shall be 0.10 %.B Optional with manufacturer and purchaser.A291/A291M 16a28. Mechani
26、cal Requirements8.1 Tensile and Impact Requirements:8.1.1 The material shall conform to the requirements for tensile and impact properties prescribed in Table 2 and impactproperties (see S2) when agreed upon between the purchaser and the supplier.8.1.2 ClassificationThe nominal or specified rough-ma
27、chined diameter or thickness of solid forgings, disregarding large ends,collars and flanges, or the nominal rough-machined wall thickness of bored forgings shall determine the size classification.8.1.3 Number, Location, and Orientation of Test Specimens:8.1.3.1 At least one tension test specimen eit
28、her longitudinal or tangential at the option of the manufacturer shall be taken fromeach forging unless a number of forgings are forged and treated in multiple, in which case one tension test specimen shall be takenfrom each end of the multiple forging. When impact tests are specified in accordance
29、with Supplementary Requirement S2, oneset of impact tests shall also be taken from each end of the multiple forging. When agreed upon between the manufacturer and thepurchaser, forgings weighing less than 500 lb 225 kg each (rough-machined weight) may be tested in lots; the number of forgingsto make
30、 up a lot shall be by mutual agreement.8.1.3.2 Tension and impact test specimens shall be taken from an extension of the main body of the forging, or from a full-sizeprolongation left on one end of each individual forging or on both ends of the multiple forging if the forgings are made in multiple.T
31、he nominal or specified outside rough-machined diameter or thickness of the forgings, disregarding large ends, collars andflanges, shall determine the size of prolongations for test specimens.8.1.3.3 The axis of the longitudinal tension test specimen shall be located at any point 114 in. 32 mm below
32、 the surface of theforging. The axis of the tangential test specimen shall be located as near to the surface of the forging as practicable.8.2 Brinell Hardness:8.2.1 The material shall conform to the requirements for hardness as prescribed in Table 2. Brinell hardness tests shallbe made on prepared
33、areas on the forgings after machining to the sizes ordered by the purchaser and after stress relieving if stressrelieving is required.8.2.2 Number and Location of TestsOn each forging 8 in. 200 mm and over in diameter, four Brinell hardness tests shallbe made on the outside surface of that portion o
34、f the forging on which teeth will be cut, two tests being made on each end 180apart and the tests on the two ends shall be 90 apart. On each forging under 8 in. 200 mm in diameter, two Brinell hardnesstests shall be made, one on each end 180 apart. On shaft forgings, two hardness tests shall be made
35、 on each end 180 apart.9. Retreatment9.1 If the results of the mechanical tests of any forging do not conform to the specified requirements, the manufacturer mayretreat the forging one or more times, but not more than three additional times without approval of the purchaser.TABLE 2 Mechanical Proper
36、tiesGrade ClassSize, SolidDiameter orThickness, in.A Tensile 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(Tangent
37、ial)1 A .1010.858058555050453453102220.164537.30. . . 170 - 2232 B .10201020.959595655655655707070485485485202018.1816454538.3430. . . 201 - 2413, 3A C, D .10201020.105105105725725725808080550550550191918.1614454538.3230. . . 223 - 2624 E .10201020.120120115825825795959590655655620161413.1210403533.
38、3025. . . 248 - 2935 F .10201020.140135130965930905115110105795760725161412.1210403530.3025. . . 285 - 3316 G .10201020.1451401351000965930120115110825795760151412.1210403530.3025. . . 302 - 3527 H .10201020.170165160137511401105140135130960930905141210.1010353025.2525. . . 341 - 4158 I . 10 120 825
39、 85 585 15 . 40 . 255 - 3029 J 20 . . . 170 1175 140 960 10 10 30 30 25 30 352 - 401A 10 in. = 250 mm. 20 in. = 500 mm.A291/A291M 16a310. Dimensions and Tolerance10.1 The forgings shall conform to the dimensions and tolerances specified on the purchasers drawing or order.11. Certification and Report
40、s11.1 Material test reports as specified in Specification A788/A788M are required and shall include the final austenitizing andtempering temperatures, holding times, and methods of cooling.12. Marking, Packaging, and Loading12.1 Each forging shall be legibly stamped by the manufacturer with the manu
41、facturers name or trademark, the manufacturersserial number,ASTM designation A291/A291M, followed by the appropriate class number. The purchaser may indicate the desiredlocation of such identification information.12.2 Packaging and loading shall be done so the forging is not damaged during shipment
42、to the purchaser.13. Keywords13.1 alloy steel forgings; carbon steel forgings; gear forgings; gear shaft forgings; heat-treated; pinion forgingsSUPPLEMENTARY REQUIREMENTSThe following supplementary requirements shall apply only when specified by the purchaser on theorder and agreed to by the manufac
43、turer.S1. Rough Turning and BoringS1.1 The position of rough turning and boring in the sequence of manufacturing operations is specified.S2. Impact TestsS2.1 Impact tests shall be made. The specimens shall be machined and tested with minimum properties and test temperaturesspecified as follows.Charp
44、y V-Notch, ftlbf J, 70 to 80F20 to 25C minCharpy V-Notch, ftlbf J, 70 to 80 F20 to 25 C minGrade Class Longitudinal Transverse (Tangential)1 A 10 13 8 112 B 10 13 8 113 C 30 40 20 273A D 30 40 20 274 E 30 40 20 275 F 25 34 15 206 G 25 34 15 207 H 20 27 10 138 I 8 11 . . .A291/A291M 16a4Charpy V-Notc
45、h, 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 8 11 . . .S3. Nondestructive ExaminationS3.1 Magnetic particle examination may be specified in accordance with Practice A275/A275M.S3.2 Ultrasonic examina
46、tion may be specified in accordance with Practice A388/A388M.S4. PhosphorusS4.1 Phosphorus shall not exceed 0.015 %, and sulfur shall not exceed 0.018 % for all classes.S5. Vacuum DegassingS5.1 The molten steel shall be vacuum treated prior to, or during, pouring of the ingot, to remove objectionabl
47、e 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 tests shall bemade on the outside surface of that portion of the forging on which teeth will be cut, two tests being made on each helix 180 apar
48、tand the tests on the two helices shall be 90 apart. On each forging under 8 in. 200 mm in diameter, two Brinell hardness testsshall be made, one on each helix 180 apart. Hardness tests shall be performed at the quarter-face width of the tooth portiondiameter. On shaft forgings, two hardness tests shall be made on each end 180 apart. When this supplement is required, thepurchaser shall supply detailed drawings indicating the location of gear teeth, the helix angle, and the location of the requiredhardness tests.APPENDIX(Nonmandatory Information)X1. PREVIOUS CLASSES AND CORRESPONDING CURRE
