1、Designation: A790/A790M 14aStandard Specification forSeamless and Welded Ferritic/Austenitic Stainless SteelPipe1This standard is issued under the fixed designation A790/A790M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the ye
2、ar 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 specification2covers seamless and straight-seamwelded ferritic/austenitic steel pipe intended for general
3、corro-sive service, with particular emphasis on resistance to stresscorrosion cracking. These steels are susceptible to embrittle-ment if used for prolonged periods at elevated temperatures.1.2 Optional supplementary requirements are provided forpipe when a greater degree of testing is desired. Thes
4、esupplementary requirements call for additional tests to be madeand, when desired, one or more of these may be specified in theorder.1.3 Appendix X1 of this specification lists the dimensions ofwelded and seamless stainless steel pipe as shown in ANSIB36.19. Pipe having other dimensions may be furni
5、shedprovided such pipe complies with all other requirements of thisspecification.1.4 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. Within the text, theSI units are shown in brackets. The values stated in eachsystem may not be exact equivalents; th
6、erefore, each systemshall be used independently of the other. Combining valuesfrom the two systems may result in non-conformance with thestandard. The inch-pound units shall apply unless the Mdesignation of this specification is specified in the order.NOTE 1The dimensionless designator NPS (nominal
7、pipe size) hasbeen substituted in this standard for such traditional terms as nominaldiameter, size, and nominal size.2. Referenced Documents2.1 ASTM Standards:3A370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA923 Test Methods for Detecting Detrimental IntermetallicPhase in
8、Duplex Austenitic/Ferritic Stainless SteelsA941 Terminology Relating to Steel, Stainless Steel, RelatedAlloys, and FerroalloysA999/A999M Specification for General Requirements forAlloy and Stainless Steel PipeE213 Practice for Ultrasonic Testing of Metal Pipe andTubingE309 Practice for Eddy-Current
9、Examination of Steel Tubu-lar Products Using Magnetic SaturationE381 Method of Macroetch Testing Steel Bars, Billets,Blooms, and ForgingsE426 Practice for Electromagnetic (Eddy-Current) Examina-tion of Seamless and Welded Tubular Products, Titanium,Austenitic Stainless Steel and Similar AlloysE527 P
10、ractice for Numbering Metals and Alloys in theUnified Numbering System (UNS)2.2 ANSI Standards:4B1.20.1 Pipe Threads, General PurposeB36.10 Welded and Seamless Wrought Steel PipeB36.19 Stainless Steel Pipe2.3 SAE Standard:5SAE J 10862.4 Other Standard:6SNT-TC-1A Personal Qualification and Certificat
11、ion inNondestructive Testing2.5 AWS Standard:7A5.9 Corrosion-Resisting Chromium and Chromium-NickelSteel Welding Rods and Electrodes3. Terminology3.1 DefinitionsFor definitions of terms used in this speci-fication refer to Terminology A941.1This specification is under the jurisdiction of ASTM Commit
12、tee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.10 on Stainless and Alloy Steel Tubular Products.Current edition approved Oct. 1, 2014. Published October 2014. Originallyapproved in 1981. Last previous edition approved in 2014 as A790/A790M14.D
13、OI: 10.1520/A0790_A0790M-14A.2For ASME Boiler and Pressure Vessel Code applications see related Specifi-cation SA790 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 ASTMStandards v
14、olume information, refer to the standards Document Summary page onthe ASTM website.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.5Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA
15、 15096-0001, http:/www.sae.org.6Available fromAmerican Society for Nondestructive Testing (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http:/www.asnt.org.7Available from American Welding Society (AWS), 550 NW LeJeune Rd.,Miami, FL 33126, http:/www.aws.org.*A Summary of Changes
16、 section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Ordering Information4.1 Orders for material under this specification shouldinclude the following, as required, to describe the desiredmater
17、ial adequately:4.1.1 Quantity (feet, metres, or number of lengths),4.1.2 Name of material (ferritic/austenitic steel pipe),4.1.3 Process (seamless or welded),4.1.4 Grade (see Table 1),4.1.5 Size (NPS designator or outside diameter and sched-ule number of average wall thickness),4.1.6 Length (specifi
18、c or random) (see Section 11),4.1.7 End finish (section on ends of Specification A999/A999M),4.1.8 Optional requirements (product analysis, Section 9;hydrostatic test or nondestructive electric test, Section 14),4.1.9 Test report required (section on certification of Speci-fication A999/A999M),4.1.1
19、0 Specification designation, and4.1.11 Special requirements and any supplementary require-ments selected.5. General Requirements5.1 Material furnished under this specification shall con-form to the applicable requirements of the current edition ofSpecification A999/A999M unless otherwise provided he
20、rein.TABLE 1 Heat TreatmentUNSDesignationTypeATemperature F C QuenchS31200 1920201010501100Rapid cooling in waterS31260 1870201010201100Rapid cooling in air or waterS31500 180019009801040Rapid cooling in air or waterS31803 1870201010201100Rapid cooling in air or waterS32003 1850205010101120Rapid coo
21、ling in air or waterS32101 1870 1020 Quenched in water or rapidlycooled by other meansS32202 1870197510201080Rapid cooling in air or waterS32205 2205 1870201010201100Rapid cooling in air or waterS32304 2304 170019209251050Rapid cooling in air or waterS32506 1870205010201120Rapid cooling in air or wa
22、terS32520 1975205010801120Rapid cooling in air or waterS32550 255 1900 1040 min Rapid cooling in air or waterS32707 1975205010801120Rapid cooling in air or waterS32750 2507 1880206010251125Rapid cooling in air or waterS32760 1960208510701140Rapid cooling in air or waterS32808 1920210010501150Rapid c
23、ooling in air or waterS32900 329 17001750925955Rapid cooling in air or waterS32906 1870210010201150Rapid cooling in air or waterS32950 182018809901025Air coolS33207 1905208510401140Rapid cooling in water or byother meansS39274 1920206010251125Rapid cooling in air or waterS39277 1975215510801180Rapid
24、 cooling in air or waterS81921 176020109601100Rapid cooling in air or waterS82011 1850205010101120Rapid cooling in air or waterS82121 1830201010001100Rapid cooling in air or waterS82441 1870 1020 Rapid cooling in air or waterACommon name, not a trademark, widely used, not associated with any oneprod
25、ucer. 329 is an AISI number.A790/A790M 14a26. Materials and Manufacture6.1 Manufacture:6.1.1 The pipe shall be made by the seamless or anautomatic welding process, with no addition of filler metal inthe welding operation.6.1.2 At the manufacturers option, pipe may be eitherhot-finished or cold-finis
26、hed.6.1.3 The pipe shall be pickled free of scale. When brightannealing is used, pickling is not necessary.6.2 DiscardA sufficient discard shall be made from eachingot to secure freedom from injurious piping and unduesegregation.6.3 Unless otherwise stated in the order, all pipe shall befurnished in
27、 the heat-treated condition as shown in Table 1.6.3.1 For seamless pipe, as an alternate to final heat treat-ment in a continuous furnace or batch-type furnace, immedi-ately following hot forming while the temperature of the pipesis not less than the specified minimum solution treatmenttemperature,
28、pipes shall be individually quenched in water orrapidly cooled by other means, except for UNS S32950, whichshall be air cooled.6.3.2 If the purchaser desires pipe without heat treatmentsubsequent to welding, the purchase order shall specify thefollowing condition:6.3.2.1 No final heat treatment of p
29、ipe fabricated from platethat has been heat treated as required by Table 1 for theparticular grade is required, provided a sample of that heat offinished pipe or material representative of that heat of pipe asa prolongation of the weld passes the Test Methods A923Method B or C (See Note 2), includin
30、g base metal, weld metal,and heat affected zone per heat. Each pipe supplied under thisrequirement shall be stenciled with the suffix “HT-O.”6.3.2.2 For materials not listed in Table 3 of Test MethodsA923, the HT-O provision does not apply.NOTE 2The Test Methods A923 test method (B or C) is at thema
31、nufacturers option, unless otherwise specified by the purchaser.7. Chemical Composition7.1 The steel shall conform to the chemical requirements asprescribed in Table 2.8. Heat Analysis8.1 An analysis of each heat of steel shall be made by thesteel manufacturer to determine the percentages of the ele
32、-ments specified.9. Product Analysis9.1 At the request of the purchasers inspector, an analysisof one billet or one length of flat-rolled stock from each heat,or two pipes from each lot, shall be made by the manufacturer.A lot of pipe shall consist of the following number of lengthsof the same size
33、and wall thickness from any one heat of steel:NPS Designator Lengths of Pipe in LotUnder 2 400 or fraction thereof2 to 5, incl 200 or fraction thereof6 and over 100 or fraction thereof9.2 The results of these analyses shall be reported to thepurchaser or the purchasers representative and shall confo
34、rmto the requirements specified in Section 7.9.3 If the analysis of one of the tests specified in 8.1 or 9.1does not conform to the requirements specified in Section 7,ananalysis of each billet or pipe from the same heat or lot may bemade, and all billets or pipe conforming to the requirementsshall
35、be accepted.10. Tensile and Hardness Properties10.1 The material shall conform to the tensile and hardnessproperties prescribed in Table 3.11. Lengths11.1 Pipe lengths shall be in accordance with the followingregular practice:11.1.1 Unless otherwise agreed upon, all sizes from NPS18to and including
36、NPS 8 are available in a length up to 24 ft (seeNote 3) with the permissible range of 15 to 24 ft (see Note 3).Short lengths are acceptable and the number and minimumlength shall be agreed upon between the manufacturer and thepurchaser.NOTE 3This value applies when the inch-pound designation of this
37、specification is the basis of purchase. When the M designation of thisspecification is the basis of purchase, the corresponding metric value(s)shall be agreed upon between the manufacturer and purchaser.11.1.2 If definite cut lengths are desired, the lengths re-quired shall be specified in the order
38、. No pipe shall be less thanthe specified length and no more than14 in. 6 mm over it.11.1.3 No jointers are permitted unless otherwise specified.12. Workmanship, Finish, and Appearance12.1 The finished pipes shall be reasonably straight andshall have a workmanlike finish. Imperfections may be re-mov
39、ed by grinding, provided the wall thicknesses are notdecreased to less than that permitted, in the PermissibleVariations in Wall Thickness Section of Specification A999/A999M.13. Mechanical Tests Required13.1 Transverse or Longitudinal Tension TestOne tensiontest shall be made on a specimen for lots
40、 of not more than 100pipes. Tension tests shall be made on specimens from 2 pipesfor lots of more than 100 pipes.13.2 Mechanical Testing Lot DefinitionThe term lot formechanical tests applies to all pipe of the same nominal sizeand wall thickness (or schedule) that is produced from the sameheat of s
41、teel and subjected to the same finishing treatment asdefined as follows:13.2.1 Where the heat treated condition is obtained, consis-tent with the requirements of 6.3, in a continuous heattreatment furnace or by directly obtaining the heat treatedcondition by quenching after hot forming, the lot shal
42、l includeall pipe of the same size and heat, heat treated in the samefurnace at the same temperature, time at heat, and furnacespeed or all pipe of the same size and heat, hot formed andquenched in the same production run.A790/A790M 14a313.2.2 Where final heat treatment is obtained, consistentwith t
43、he requirements of 6.3, in a batch-type heat-treatmentfurnace equipped with recording pyrometers and automaticallycontrolled within a 50 F 30 C or smaller range, the lot shallbe the larger of (a) each 200 ft 60 m or fraction thereof or (b)that pipe heat treated in the same batch furnace charge.13.2.
44、3 Where the final heat treatment is obtained, consistentwith the requirements of 6.3, in a batch-type heat-treatmentfurnace not equipped with recording pyrometers and automati-cally controlled within a 50 F 30 C or smaller range, theterm lot for mechanical tests applies to the pipe heat treated inth
45、e same batch furnace charge, provided that such pipe is of thesame nominal size and wall thickness (or schedule) and isproduced from the same heat of steel.13.3 Flattening TestFor pipe heat treated in a batch-typefurnace, flattening tests shall be made on 5 % of the pipe fromeach heat-treated lot. F
46、or pipe heat treated by the continuousprocess, or by direct quenching after hot forming, this test shallbe made on a sufficient number of pipes to constitute 5 % of thelot, but in no case less than two lengths of pipe.13.3.1 For welded pipe with a diameter equal to or exceed-ing NPS 10, a transverse
47、 guided face bend test of the weld maybe conducted instead of a flattening test in accordance with themethod outlined in the steel tubular product supplement of TestMethods and Definitions A370. The ductility of the weld shallbe considered acceptable when there is no evidence of cracksin the weld or
48、 between the weld and the base metal afterbending. Test specimens from 5 % of the lot shall be takenfrom the pipes or test plates of the same material as the pipe,the test plates being attached to the end of the cylinder andwelded as a prolongation of the pipe longitudinal seam.13.4 Hardness TestBri
49、nell or Rockwell hardness testsshall be made on specimens from two pipes from each lot (see13.2).TABLE 2 Chemical RequirementsAUNSDesigna-tionBTypeCC Mn P S Si Ni Cr Mo N Cu OthersS31200 0.030 2.00 0.045 0.030 1.00 5.56.5 24.026.0 1.202.00 0.140.20 . . . . . .S31260 0.030 1.00 0.030 0.030 0.75 5.57.5 24.026.0 2.53.5 0.100.30 0.200.80 W0.100.50S31500 0.030 1.202.00 0.030 0.030 1.402.00 4.25.2 18.019.0 2.503.00 0.050.10 . . . . . .S31
