ASTM A765 A765M-2007(2012) Standard Specification for Carbon Steel and Low-Alloy Steel Pressure-Vessel-Component Forgings with Mandatory Toughness Requirements《具有强制性韧性要求的碳素钢及低合金钢压力.pdf

1、Designation: A765/A765M 07 (Reapproved 2012)Standard Specification forCarbon Steel and Low-Alloy Steel Pressure-Vessel-Component Forgings with Mandatory ToughnessRequirements1This standard is issued under the fixed designation A765/A765M; the number immediately following the designation indicates th

2、e yearof original adoption 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. Scope1.1 This specification2covers heat-treated carbon stee

3、l andalloy steel forgings with mandatory toughness requirements.These forgings are intended for pressure vessels, feedwaterheaters, and similar uses.1.2 These forgings include tube sheets, covers, channelbarrels, integral forged channels, rings, nozzles, flanges, andsimilar parts.1.3 All grades are

4、considered weldable under proper condi-tions.1.4 The maximum thickness of forgings produced to thisspecification is limited only by the capacity of the selectedgrade to respond to any heat treatment specified and to meet thespecified mechanical tests, including impact tests at the speci-fied tempera

5、ture.1.5 Material supplied to this specification shall conform tothe requirements of Specification A788/A788M, which out-lines additional ordering information, manufacturing require-ments, testing and retesting methods and procedures, marking,certification, product analysis variations, and additiona

6、l supple-mentary requirements.1.6 If the requirements of this specification are in conflictwith the requirements of Specification A788/A788M, therequirements of this specification shall prevail.1.7 The values stated in either inch-pound units or SImetric units are to be regarded separately as the st

7、andard;within the text and tables, the SI units are shown in brackets.The values stated in each system are not exact equivalents;therefore, each system must be used independently of the other.Combining values from the two systems may result in noncon-formance with the specification.1.8 Unless the or

8、der specifies the applicable “M” specifica-tion designation, the material shall be furnished to the inch-pound units.2. Referenced Documents2.1 ASTM Standards:3A275/A275M Practice for Magnetic Particle Examinationof Steel ForgingsA370 Test Methods and Definitions for Mechanical Testingof Steel Produ

9、ctsA388/A388M Practice for Ultrasonic Examination of SteelForgingsA788/A788M Specification for Steel Forgings, General Re-quirementsE112 Test Methods for Determining Average Grain SizeE165 Practice for Liquid Penetrant Examination for GeneralIndustry2.2 ASME Standards:4ASME Boiler and Pressure Vesse

10、l Code3. Ordering Information3.1 In addition to the ordering information requirements ofSpecification A788/A788M, a detailed sketch or written de-scription of the forging and the method of selecting the testlocation (see 6.2) should be supplied to the producer, whenappropriate areas of significant i

11、n-service loading of theforging need to be designated.3.2 The required impact test temperature should be suppliedif different than the temperature listed in Table 3, otherwise theimpact test shall be conducted at the temperature listed in Table3 for the chosen Grade.3.3 If a hubbed tube sheet is to

12、be supplied forASME Boilerand Pressure Code Application Supplementary RequirementS12 of Specification A788/A788M shall be specified.3.4 If steel is required to be vacuum degassed, Supplemen-tary Requirement S8 of Specification A788/A788M should bespecified.1This specification is under the jurisdicti

13、on 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 1979. Last previous edition approved in 2007 as A765/A765M 07.DOI:

14、 10.1520/A0765_A0765M-07R12.2For ASME Boiler and Pressure Vessel Code applications see related Specifi-cation SA765/SA765M in Section II of that code.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStand

15、ards volume information, refer to the standards Document Summary page onthe ASTM website.4Available from American Society of Mechanical Engineers, 345 E. 47th St.,New York, NY 10017.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.

16、Heat Treatment for Mechanical Properties4.1 Heat treatment shall consist of one of the following heattreatment options of the manufacturers choice.4.1.1 Normalize and temper.4.1.2 Double normalize, wherein the second austenitizingtemperature is at the same or lower temperature than the first,followe

17、d by tempering.4.1.3 Quench and temper, with the option of adding apreliminary normalize before austenitizing for quenching in asuitable liquid medium. The type of cooling medium used shallbe reported.4.1.4 Use of an intercritical heat treatment cycle in accor-dance with Specification A788/A788M in

18、which cooling fromthe full and partial austenitization stages may be done by liquidquenching or air cooling. The method of cooling and type ofquench medium, if used, shall be reported.4.1.5 The minimum tempering temperature shall be 1100F590C.5. Chemical Requirements5.1 Heat AnalysisThe heat analysi

19、s obtained from sam-pling in accordance with Specification A788/A788M shallcomply with Table 1.5.2 Product AnalysisThe purchaser may use the productanalysis provision of Specification A788/A788M to obtain aproduct analysis from a forging representing each heat ormultiple heat.6. Mechanical Requireme

20、nts6.1 General RequirementsThe forgings shall conform tothe tension test requirements of Table 2. The forgings shall alsoconform to the impact test requirements of Table 3. The largestobtainable round tension test specimen as specified in TestMethods and DefinitionsA370 shall be used. Impact specime

21、nsshall be Charpy V-notch, Type A, as in Test Methods andDefinitionsA370. The usage of subsize impact specimens musthave prior purchaser approval.6.1.1 When agreed upon between the purchaser and theproducer and specified on the order, impact tests may be madeat temperatures different from those show

22、n in Table 3 providedthe test temperature is at least as low as the intended servicetemperatures and the provided impact energy requirements ofTable 3 are met. Such forgings shall be suitably marked inaccordance with 9.1 to identify the test temperature.6.2 Test LocationTest coupons shall be taken s

23、o that thelongitudinal axis and mid-length of tension and impact testspecimens shall be positioned in accordance with one of thefollowing methods:6.2.1 Method 1Forgings with 2 in. 50 mm maximumthickness. The specimens shall have their longitudinal axis atthe midthickness or the center of the cross s

24、ection and with themidlength of the specimen at least 2 in. 50 mm from anysecond surface.6.2.2 Method 2Grade I and Grade II forgings with thick-nesses greater than 2 in. up to 4 in. 50 to 100 mm inclusive,or Grade III and IV forgings with thicknesses greater than 2 in.up to 6 in. 50 to 150 mm inclus

25、ive. The specimens shall havetheir longitudinal axis at least14 T of maximum heat-treatedthickness from any surface and with the midlength of thespecimen at least one T from any second surface. This isnormally referred to as14 T by T when T is the maximumheat-treated thickness. A thermal buffer may

26、be used to adhereto the condition in 6.3. Unless otherwise agreed upon, thefollowing limitation for heat-treated thickness shall apply:Grade in. mm, min in. mm, maxI 2 50 4 100II 2 50 4 100III 2 50 6 150IV 2 50 6 150V(Classes 1 and 2)2 50 6 1506.2.3 Method 3For forgings thicker than described inMeth

27、od 2 (6.2.2):6.2.3.1 Prior to heat treatment the forging shall be machinedto a purchaser supplied or approved drawing that indicates thelocations of significant in-service loading in the finished part.The mechanical test specimens shall be located as an integralpart of the forging such that the mid-

28、point of the gauge lengthof the tension test specimen and the area under the notch of theimpact specimens are located no closer than the dimension tfrom one heat treated surface and 2t from any other heat treatedsurface where t is the dimension from the area of significantloading to the heat treated

29、 surface, or34 in. 20 mm whicheveris the greater.6.2.4 Method 4This method shall be limited to forgingswith a rough machined weight of not more than 1000 lb 455kg. Separate test forging when agreed upon between thepurchaser and the supplier. Test coupons representing forgingsfrom one heat and one he

30、at treatment lot may be taken from aseparately forged piece under the following conditions:6.2.4.1 The separate test forging shall be of the same heat ofmaterial and shall be subjected to substantially the samereduction and working as the production forging it represents.6.2.4.2 The separate test fo

31、rging shall be heat treated in thesame furnace charge and under the same conditions as theproduction forging.6.2.4.3 The separate test forging shall be of the samenominal thickness as the production forging.TABLE 1 Chemical RequirementsComposition, %Grade I Grade II Grade III Grade IV Grade VCarbon,

32、 max 0.30 0.30 0.20 0.20 0.30Manganese 0.60 to1.350.60 to1.350.90 max 1.001.60 0.601.35Phosphorus,max0.020 0.020 0.020 0.020 0.020Sulfur, max 0.020 0.020 0.020 0.020 0.020Silicon 0.15 to0.350.15 to0.350.15 to0.350.150.50 0.150.35Nickel, maxA0.50 0.50 3.3 to 3.8 0.50 max 1.02.0Vanadium, max 0.05 0.05

33、 0.05 0.06 0.03Aluminum, max 0.05 0.05 0.05 0.05 0.05Chromium,Amax0.40 0.40 0.20 0.40 0.30Molybdenum,Amax0.10 0.10 0.06 0.10 0.12Copper, max 0.35 0.35 0.35 0.35 0.35AIntentional additions of Cr, Mo, and Ni up to the specified maximum arepermitted to be made to Grades I, II, and IV by the manufacture

34、r.A765/A765M 07 (2012)26.2.4.4 Test coupons for small forgings as described inMethod 2 shall be taken so that specimens shall have theirlongitudinal axes at the region midway between midthicknessand the surface and with the midlength of the specimens nonearer any heat-treated edge than a distance eq

35、ual to theforging thickness except when the thickness-to-length ratio ofthe production forging does not permit, in which case aproduction forging shall be used as the test forging and themidlength of the specimens shall be at the midlength of the testforging.6.2.4.5 Test coupons for larger forgings

36、shall be taken inaccordance with Method 3 (6.2.3).6.3 Metal BuffersThe required distances from treatedsurfaces may be obtained with metal buffers instead of integralextensions. Buffer material may be carbon or low-alloy steel,and shall be joined to the forging with a partial penetrationweld that sea

37、ls the buffered surface. Specimens shall be locatedat12 in. 13 mm minimum from the buffered surface of theforging. Buffers shall be removed and the welded areassubjected to magnetic particle test to assure freedom fromcracks unless the welded areas are completely removed bysubsequent machining.6.4 S

38、amples shall be removed from forgings after heattreatments. This sample material shall be subjected to asimulated post-weld heat treatment if Supplementary Require-ment S6 is specified.6.5 Test Orientation:6.5.1 For upset disk forgings such as tube sheets thelongitudinal axis of test specimens may b

39、e oriented in theradial or tangential direction, or parallel to the axis of theforging, as shown in Supplementary Requirement S12 ofSpecification A788/A788M.6.5.2 For all other forgings the longitudinal axis of testspecimens may be oriented parallel to the direction of maxi-mum hot working of the fo

40、rging.6.6 Number of Tests:6.6.1 Forgings Under 500 lb 230 kg As TreatedForduplicate forgings weighing less than 500 lb as treated, onetension test and one impact test (three specimens) shall bemade to represent each heat in each heat-treatment charge.When heat treatment is performed in continuous-ty

41、pe furnaceswith suitable temperature control and equipped with recordingpyrometers so that complete heat-treatment records are avail-able, a heat-treatment charge shall be considered as anycontinuous run not exceeding an 8-h duration.6.6.2 Forging Weighing 500 to 10 000 lb 230 to 4500 kgAs-Heat Trea

42、tedOne tension and one impact test (threespecimens) shall be made for each forging.6.6.3 Each forging weighing over 10 000 lb 4500 kg shallrequire two tension tests and two impact tests (three speci-mens). When the length (excluding prolongs) is equal to or lessthan 112 times the diameter, the tests

43、 may be taken from oneend of the forging with a tension test and one set of impact testsat each of two locations oriented 180 apart. When the length(excluding prolongs) is greater than 112 times the diameter,one tension test and one set of impact tests must be taken fromeach location from opposite e

44、nds of the forging and thelocations on each end should be oriented 180 apart from eachother.7. Repair Welding7.1 Repair welding, as permitted by the purchaser, shall beperformed in accordance with the ASME Boiler and PressureVessel Code.8. Reporting8.1 The type of quenching medium used for the heatt

45、reatment cycle in 4.1.3 shall be reported, or in the case of4.1.4, whether air cooling or quenching was used and the typeof quench medium if applicable. The other certification re-quirements of Specification A788/A788M also apply.9. Product Marking9.1 The test temperature, if different from that giv

46、en inTable 3, shall be marked on the forging as a suffix to the Gradeand Class designation. A prefix of 0 to the test temperatureindicates that the temperature was under 0F, or 0C if the MTABLE 2 Tensile RequirementsGrade I Grade II Grade III Grade IV Grade VClass 1 Class 2Tensile strength, ksi MPa

47、60 to 85415 to 58570 to 95485 to 65570 to 95485 to 655801055507256085415 5857095485655Yield strength,Ain, ksi MPa 30 205 36 250 37.5 260 50 345 30 205 37.5 260Elongation in 2 in. 50 mm,min, %25 22 22 22 25 22Reduction of area, min, % 38 30 35 30 38 35A0.2 % offset or 0.5 % total extension underload

48、method.TABLE 3 Charpy V-Notch Impact RequirementsGrade I Grade II Grade III Grade IV Grade V(Classes 1 and 2)Minimum average value of set of three specimens, ft-lbf (J) 13 18 15 20 15 20 26 35A15 20Minimum value of one specimen, ft-lbf (J) 10 14 12 16 12 16 20 27A12 16Test temperature of,BF C 20 30

49、50 45 150 100 20 30 -75 -60AMandatory conformance to the values listed is a matter of agreement between the purchaser and the manufacturer. The energy values above are shown for informationas to guarantees that are generally available.BActual test temperature should be established at time of order. If no temperature is specified, tests will be made at test temperatures shown in this table.A765/A765M 07 (2012)3designation speci