1、Designation: A469/A469M 07 (Reapproved 2012)Standard Specification forVacuum-Treated Steel Forgings for Generator Rotors1This standard is issued under the fixed designation A469/A469M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision
2、, 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. Scope1.1 This specification covers vacuum-treated basic electricsteel forgings for generator rotors.1.2 Supplemen
3、tary requirements are provided, both in thisstandard and in Specification A788/A788M, for use whenadditional testing, inspection or processing is required by thepurchaser.1.3 The values stated in either inch-pound or SI (metric)units are to be regarded separately as standards. Within the textand tab
4、les, the SI units are shown in brackets. The values statedin each system are not exact equivalents; therefore, eachsystem must be used independent of the other. Combiningvalues from the two systems may result in nonconformancewith the specification.1.4 Unless the order specifies the applicable “M” s
5、pecifica-tion designation, the material shall be furnished to the inch-pound units.2. Referenced Documents2.1 ASTM Standards:2A275/A275M Practice for Magnetic Particle Examinationof Steel ForgingsA341/A341M Test Method for Direct Current MagneticProperties of Materials Using D-C Permeameters and the
6、Ballistic Test MethodsA370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA418/A418M Practice for Ultrasonic Examination of Tur-bine and Generator Steel Rotor ForgingsA773/A773M Test Method for dc Magnetic Properties ofMaterials Using Ring and Permeameter Procedures withdc Elect
7、ronic HysteresigraphsA788/A788M Specification for Steel Forgings, General Re-quirements3. Ordering Information and General Requirements3.1 In addition to the ordering information required bySpecification A788/A788M, the purchaser shall include withthe inquiry and order, a dimensioned drawing showing
8、 themechanical test specimen locations, together with:3.1.1 Details of any required magnetic permeability tests(6.1).3.1.2 If the yield strength is to be determined at an offset of0.2%(Table 1), and number of tests (7.1.2 and 7.1.3).3.1.3 If vertical heat treatment is required (S3).3.1.4 If heat tre
9、atment by normalizing and tempering isrequired (4.2.2 and 4.2.3).3.1.5 If post rough machining stress relief may be omittedfor forgings that have been double tempered (4.2.2).3.1.6 Details for boring including dimensions, finish, timingand additional testing if required (8.3 and S1).3.1.7 Any applic
10、able instructions regarding the requirednondestructive examinations (8).3.1.8 If vacuum arc remelted ingots are to be used, thepurchaser may require that footnote A to Table 2 be applicable.3.2 Material supplied to this specification shall conform tothe requirements of Specification A788/A788M, whic
11、h out-lines additional ordering information, manufacturing require-ments, testing and retesting methods and procedures, marking,certification, production analysis variations, and additionalsupplementary requirements.3.3 Failure to comply with the applicable general require-ments of Specification A78
12、8/A788M constitutes nonconfor-mance with this specification.3.4 If the requirements of this specification are in conflictwith the requirements of Specification A788/A788M, therequirements of this specification shall prevail.4. Materials and Manufacture4.1 The vacuum degassing requirements of Specifi
13、cationA788/A788M are mandatory.4.1.1 Other vacuum methods of degassing may be used ifthe supplier can demonstrate their adequacy to the satisfactionof the purchaser, but in this case, hydrogen testing perSupplementary Requirement S4 is mandatory.4.2 Heat Treatment:1This specification is under the ju
14、risdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.06 on Steel Forgings and Billets.Current edition approved May 1, 2012. Published May 2012. Originallyapproved in 1962. Last previous edition approved in 2007 as A469/A469M
15、 07.DOI: 10.1520/A0469_A0469M-07R12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM Internati
16、onal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2.1 Vertical heat treatment of the rotor forging is pre-ferred, and Supplementary Requirement S3 should be specifiedby the purchase order if this is required.4.2.2 The heat treatment for mechanical properties
17、 shallconsist of quenching and tempering, but normalizing andtempering is permissible with prior purchaser approval. Also,with prior purchaser approval, the post rough machining stressrelief in 4.2.3 may be omitted when double tempering is used,instead of a single temper, to complete this heat treat
18、mentcycle.4.2.3 After heat treatment and the subsequent rough ma-chining, the forging shall be stress relieved at a minimumtemperature of 1050F 565C, unless otherwise specified bythe purchaser.4.3 Machining:4.3.1 BoringThe manufacturer may bore the forging atany time prior to stress-relief anneal. (
19、See SupplementaryRequirement S1).5. Chemical Composition5.1 Heat AnalysisThe heat analysis obtained from sam-pling in accordance with Specification A788/A788M shallcomply with Table 2.5.2 Product AnalysisThe manufacturer shall use the prod-uct analysis provision of Specification A788/A788M to obtain
20、a product analysis from a forging representing each heat ormultiple heat.6. Magnetic Properties6.1 When specified in the ordering information, a perme-ability test shall be performed in accordance with the latestissue of Test Method A341/A341M or Test Method A773/A773M.7. Mechanical Properties7.1 Te
21、nsion Test:7.1.1 The steel shall conform to the requirements of Table 1.7.1.2 The number and locations of tension test specimensshall be as specified on the forging drawings furnished by thepurchaser.7.1.3 Tests for acceptance shall be made after heat treatmentof the forging for mechanical propertie
22、s; however, the ultra-sonic examination requirements of 8.2.3 must be considered.The purchaser may require check tests after completion of allheating cycles including stress relieving in accordance with4.2.3.7.1.4 Testing shall be performed in accordance with thelatest issue of Test Methods and Defi
23、nitions A370.7.1.5 The yield strength prescribed in Table 1 shall bedetermined by the offset method at 0.02 % as described in TestMethods and Definitions A370.7.2 Impact Test:7.2.1 The material shall conform to the requirements fornotch toughness (both fracture appearance transition tempera-ture (FA
24、TT) and room temperature absorbed energy value)prescribed in Table 1.TABLE 1 Tensile and Notch Toughness RequirementsGrade2345678Tensile strength, min, ksi 80 90 100 110 100 110 120MPa 550 620 690 760 690 760 825Yield strength,Amin, ksi 55 70 80 90 80 90 100MPa 380 485 550 620 550 620 690Elongation
25、in 2 in. or 50 mm, min, % 20 20 17 15 18 17 16Reduction of area, min, % 50 50 45 40 55 50 45FATT50, max, F 100 100 120 175 0 20 40FATT50, max, C 38 38 49 80 18 7 4Charpy absorbed energy at 70 6 5F 20 6 3 C,30 30 25 15 60 50 40min, ftlbfJ 40 40 34 20 80 68 55AYield strength at 0.02 % offset. Yield st
26、rength may also be specified at 0.2 % offset in which case 5000 psi (35 MPa) shall be added to these values.TABLE 2 Chemical RequirementsElement Composition, %Grade 2 Grade 3 Grade 4 Grade 5 Grades 6, 7, 8Carbon, max 0.25 0.27 0.27 0.31 0.28Manganese, max 0.60 0.60 0.70 0.70 0.60Phosphorus, max 0.01
27、5 0.015 0.015 0.015 0.015Sulfur, max 0.015 0.015 0.015 0.015 0.015Silicon, maxA0.30 0.30 0.30 0.30 0.30Nickel 2.50 min 2.50 min 3.00 min 3.00 min 3.25 to 4.00Chromium 0.50 max 0.50 max 0.50 max 0.50 max 1.25 to 2.00Molybdenum 0.20 to 0.50 0.20 to 0.50 0.20 to 0.60 0.20 to 0.70 0.30 to 0.60Vanadium 0
28、.03 min 0.03 min 0.03 min 0.05 to 0.15 0.05 to 0.15AntimonyB. . . . .AOptional: For steel that is to be vacuum arc remelted a minimum silicon of 0.15 % may be specified.BReport for information on Grades 6, 7, and 8.A469/A469M 07 (2012)27.2.2 Charpy V-notch specimens from surface radial testlocations
29、 shall be oriented with the root of the notch perpen-dicular to a radial axis of the forging and parallel to thelongitudinal axis of the forging. The notch shall be located asfar below the heat treated surface of the forging as possiblewithout exceeding the dimensions specified for the test mate-ria
30、l. The actual distance from the outside diameter of theforging to the specimen notch shall be reported.8. Nondestructive Test Requirements8.1 General RequirementsThe forgings shall be free ofcracks, seams, laps, shrinkage, and other injurious imperfec-tions.8.2 Ultrasonic Inspection:8.2.1 An ultraso
31、nic inspection shall be made at the forgingmanufacturers plant on the machined forgings. In making theultrasonic inspection, reference shall be made to the latest issueof Test Method A418/A418M.8.2.2 Forgings having recordable ultrasonic indicationsshall be referred to the purchaser and evaluated on
32、 the basis ofnature, frequency, and locations of indications both travelingand stationary. If the ultrasonic indications are consideredobjectionable, it shall be determined by conventional or mutu-ally acceptable inspection procedures whether the forging willbe rejected.8.2.3 Forgings shall be ultra
33、sonically examined prior toremoval of the mid-body radial tension coupons.8.3 Internal InspectionBoring, when specified for bore-scope inspection, shall be as shown on the drawings furnishedby the purchaser. The drawings shall specify the nominaldimensions and surface finish of the hole. Magnetic pa
34、rticleexamination of the bore surface shall be performed in accor-dance with the latest issue of Test Method A275/A275M. Themanufacturer shall report the results of the examination to thepurchaser and any further action shall be taken only aftermutual agreement.9. Retreatment9.1 If the results of th
35、e mechanical tests of any forging donot conform to the requirements specified, the manufacturermay retreat the forging one or more times, but not more thanthree additional times without approval of the purchaser, andretests shall be made in accordance with 7.1.2.9.2 If boring, specified under Supple
36、mentary RequirementsS1, was completed, the remaining portions of the bore coreshall be replaced in the bore during retreatment.10. Certification and Reports10.1 In addition to the requirements of Specification A788/A788M, the product analysis results shall be reported.11. Packaging and Package Marki
37、ng11.1 In addition to the marking requirements of Specifica-tion A788/A788M, axial bores, if any, shall be protected andsuitably plugged for shipment or storage.12. Keywords12.1 generator rotor forgings; steel forgings; vacuum-treated steel; vertical heat treatment; yield strength at 0.02 %offsetSUP
38、PLEMENTARY REQUIREMENTSThe following supplementary requirements shall apply only when specified by the purchaser on theorder.S1. Bore Core TestsS1.1 The purchaser may require physical tests from the barcored from the longitudinal bore of the forging. These coretests will be for information only.S1.2
39、 Specimens for bore core tests shall be cored from theforging after heat treatment for mechanical properties.S2. Method of ForgingS2.1 The purchaser may specify that hot working be per-formed on a press.S3. Vertical Heat TreatmentS3.1 Heat treatment for mechanical properties shall beperformed with t
40、he forging in the vertical position.S4. Hydrogen DeterminationS4.1 A hydrogen determination shall be made. The accept-able hydrogen limit as well as the stage in processing whensampling, the sample preparation procedure and the method ofanalysis shall be as agreed upon by manufacturer and pur-chaser
41、.S5. Magnetic Particle ExaminationS5.1 A magnetic particle examination of the completeexterior and bore surfaces of the machined forging shall bemade at the forging manufacturers plant. The examinationshall be performed in accordance with the latest issue of TestMethod A275/A275M.S5.2 The purchaser
42、shall establish the minimum length oflinear indications to be considered relevant.S5.3 Forgings with either cracks or relevant linear indica-tions are subject to rejection unless they can be removed to thepurchasers satisfaction.S6. Silicon ContentS6.1 The maximum silicon content shall be 0.10 %.A46
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44、f such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for
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46、o the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).A469/A469M 07 (2012)4
