1、Designation: A 765/A 765M 07Standard Specification forCarbon Steel and Low-Alloy Steel Pressure-Vessel-Component Forgings with Mandatory ToughnessRequirements1This standard is issued under the fixed designation A 765/A 765M; the number immediately following the designation indicates the yearof origi
2、nal 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification2covers heat-treated carbon steel andalloy s
3、teel 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 considered w
4、eldable 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 temperature.1.5 Mat
5、erial supplied to this specification shall conform tothe requirements of Specification A 788/A 788M, which out-lines additional ordering information, manufacturing require-ments, testing and retesting methods and procedures, marking,certification, product analysis variations, and additional supple-m
6、entary requirements.1.6 If the requirements of this specification are in conflictwith the requirements of Specification A 788/A 788M, 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 standard;w
7、ithin 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 order spec
8、ifies the applicable “M” specifica-tion designation, the material shall be furnished to the inch-pound units.2. Referenced Documents2.1 ASTM Standards:3A 275/A 275M Practice for Magnetic Particle Examinationof Steel ForgingsA 370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA
9、388/A 388M Practice for Ultrasonic Examination ofHeavy Steel ForgingsA 788/A 788M Specification for Steel Forgings, GeneralRequirementsE112 Test Methods for Determining Average Grain SizeE 165 Test Method for Liquid Penetrant Examination2.2 ASME Standards:4ASME Boiler and Pressure Vessel Code3. Orde
10、ring Information3.1 In addition to the ordering information requirements ofSpecification A 788/A 788M, a detailed sketch or writtendescription of the forging and the method of selecting the testlocation (see 6.2) should be supplied to the producer, whenappropriate areas of significant in-service loa
11、ding 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 be supplied f
12、orASME Boilerand Pressure Code Application Supplementary RequirementS12 of Specification A 788/A 788M shall be specified.1This 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 For
13、gings and Billets.Current edition approved Sept. 1, 2007. Published October 2007. Originallyapproved in 1979. Last previous edition approved in 2004 as A 765/A 765M 04.2For ASME Boiler and Pressure Vessel Code applications see related Specifi-cation SA765/SA765M in Section II of that code.3For refer
14、enced 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.4Available from American Society of Mechanical Engineers, 345 E. 47th S
15、t.,New York, NY 10017.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.4 If steel is required to be vacuum degassed, Supplemen-tary Requirement S8 of Specification A
16、788/A 788M should bespecified.4. 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 t
17、emperature than the first,followed 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
18、with SpecificationA 788/A 788M in 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 Requirement
19、s5.1 Heat AnalysisThe heat analysis obtained from sam-pling in accordance with Specification A 788/A 788M shallcomply with Table 1.5.2 Product AnalysisThe purchaser may use the productanalysis provision of Specification A 788/A 788M to obtain aproduct analysis from a forging representing each heat o
20、rmultiple heat.6. Mechanical Requirements6.1 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 Definit
21、ions A 370 shall be used. Impact speci-mens shall be Charpy V-notch, Type A, as in Test Methods andDefinitions A 370. The usage of subsize impact specimensmust have prior purchaser approval.6.1.1 When agreed upon between the purchaser and theproducer and specified on the order, impact tests may be m
22、adeat temperatures different from those shown 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.
23、2 Test LocationTest coupons shall be taken so 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 att
24、he midthickness or the center of the cross section 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 great
25、er than 2 in.up to 6 in. 50 to 150 mm inclusive. 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 maximumh
26、eat-treated thickness. A thermal buffer may 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
27、 3For forgings thicker than described inMethod 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 in
28、tegralpart of the forging such that the mid-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 ar
29、ea of significantloading to the heat treated 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 r
30、epresenting forgingsfrom one heat and one heat 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 forgin
31、g it represents.TABLE 1 Chemical RequirementsComposition, %Grade I Grade II Grade III Grade IV Grade VCarbon, 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
32、.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 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
33、Cr, Mo, and Ni up to the specified maximum arepermitted to be made to Grades I, II, and IV by the manufacturer.A 765/A 765M 0726.2.4.2 The separate test forging shall be heat treated in thesame furnace charge and under the same conditions as theproduction forging.6.2.4.3 The separate test forging sh
34、all be of the samenominal thickness as the production forging.6.2.4.4 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 a
35、ny heat-treated edge than a distance equal 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.
36、2.4.5 Test coupons for larger forgings 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
37、with a partial penetrationweld that seals 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 complete
38、ly removed bysubsequent machining.6.4 Samples 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 thelo
39、ngitudinal axis of test specimens may be oriented in theradial or tangential direction, or parallel to the axis of theforging, as shown in Supplementary Requirement S12 ofSpecification A 788/A 788M.6.5.2 For all other forgings the longitudinal axis of testspecimens may be oriented parallel to the di
40、rection of maxi-mum hot working of the forging.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 hea
41、t treatment is performed in continuous-type 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 50
42、0 to 10 000 lb 230 to 4500 kgAs-Heat TreatedOne 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 l
43、essthan 112 times the diameter, the tests 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 b
44、e taken fromeach location from opposite ends 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 ty
45、pe of quenching medium used for the heattreatment cycle in 4.1.3 shall be reported, or in the case of4.1.4, whether air cooling or quenching was used and the typeTABLE 2 Tensile RequirementsGrade I Grade II Grade III Grade IV Grade VClass 1 Class 2Tensile strength, ksi MPa 60 to 85415 to 58570 to 95
46、485 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 method.TABLE 3 Charpy V-No
47、tch 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 50 45 150 100 20 30 -75 -6
48、0AMandatory 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 speci
49、fied, tests will be made at test temperatures shown in this table.A 765/A 765M 073of quench medium if applicable. The other certification re-quirements of Specification A 788/A 788M also apply.9. Product Marking9.1 The test temperature, if different from that given 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
