1、Designation: A 774/A 774M 06Standard Specification forAs-Welded Wrought Austenitic Stainless Steel Fittings forGeneral Corrosive Service at Low and ModerateTemperatures1This standard is issued under the fixed designationA 774/A 774M; the number immediately following the designation indicates the yea
2、rof 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers five grades of as-welded,wr
3、ought austenitic stainless steel fittings for low-pressurepiping and intended for low and moderate temperatures andgeneral corrosive service. Users should note that certaincorrosive conditions may restrict the use of one or more grades.For applications requiring a product that requires heat treat-me
4、nt or full pressure rating, refer to Specification A 403/A 403M. The term “fittings” applies to butt and socket weldingparts such as 45 and 90 elbows, tees, reducers, wyes, laterals,crosses, and stub ends.1.2 This specification covers as-welded fittings 3 through 48in. 75 through 1225 mm in outside
5、diameter and in nominalwall thicknesses 0.062 through 0.500 in. 1.6 through 12.7mm. Table 1 and Table 2 list the common diameters andnominal thicknesses of fittings in this specification.1.3 This specification does not apply to cast fittings. Castaustenitic steel fittings are covered by Specificatio
6、n A 351/A 351M.1.4 Optional supplementary requirements are provided forfittings where a greater degree of examination is desired. Thesesupplementary requirements call for additional tests. Whendesired, one or more of these may be specified in the order.1.5 This specification is expressed in both inc
7、h-pound unitsand in SI units. However, unless the order specifies theapplicable “M” specification designation (SI units), the mate-rial shall be furnished to inch-pound units.1.6 The values stated in either inch-pound units or SI unitsare to be regarded separately as standard. Within the text, theSI
8、 units are shown in brackets. The values stated in eachsystem are not exact equivalents; therefore, each system mustbe used independently of the other. Combining values from thetwo systems may result in nonconformance with the specifi-cation.2. Referenced Documents2.1 In addition to those reference
9、documents listed inSpecification A 960/A 960M, the following list of standardsapply to this specification:2.2 ASTM Standards:2A 240/A 240M Specification for Chromium andChromium-Nickel Stainless Steel Plate, Sheet, and Stripfor Pressure Vessels and for General ApplicationsA 351/A 351M Specification
10、for Castings, Austenitic, forPressure-Containing PartsA 403/A 403M Specification for Wrought Austenitic Stain-less Steel Piping FittingsA 960/A 960M Specification for Common Requirementsfor Wrought Steel Piping FittingsE 527 Practice for Numbering Metals and Alloys (UNS)2.3 ASME Standard:Section IX
11、, Welding Qualtifications, ASME Boiler andPressure Vessel Code32.4 MSS Standard:SP 43 Wrought Stainless Steel Butt Welding Fittings42.5 AWS Standards:A5.4 Corrosion-Resisting Chromium and Chromium-Nickel Steel Covered Welding Electrodes5A5.9 Corrosion-Resisting Chromium and Chromium-Nickel Steel Wel
12、ding Rods and Bare Electrodes52.6 SAE Standard:J1086 Unified Numbering System for Metals and Alloys61This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel, and Related Alloys and is the direct responsibility of SubcommitteeA01.22 on Steel Forgings and Wrought Fi
13、ttings for Piping Applications and BoltingMaterials for Piping and Special Purpose Applications.Current edition approved March 1, 2006. Published March 2006. Originallyapproved in 1980. Last previous edition approved in 2002 as A 774/A 774M 02.2For referenced ASTM standards, visit the ASTM website,
14、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.3Available from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Three Park Ave., New
15、 York, NY 10016-5990.4Available from Manufacturers Standardization Society of the Valve and FittingsIndustry (MSS), 127 Park St., NE, Vienna, VA 22180-4602.5Available from American Welding Society (AWS), 550 NW LeJeune Rd.,Miami, FL 33126.6Available from Society of Automotive Engineers (SAE), 400 Co
16、mmonwealthDr., Warrendale, PA 15096-0001.1*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. Ordering Information3.1 See Specification A 960/A 960M and the following:3.
17、1.1 Dimensions (outside diameter and specified wallthickness, see Table 1 and Table 2),3.1.2 Grade (Table 3), and3.1.3 End use, if known.4. General Requirements4.1 Product furnished to this specification shall conform tothe requirements of Specification A 960/A 960M, includingany supplementary requi
18、rements that are indicated in thepurchase order. Failure to comply with the requirements ofSpecification A 960/A 960M constitutes non-conformancewith this specification. In case of a conflict between therequirements of this specification and Specification A 960/A 960M, this specification shall preva
19、il.5. Manufacture5.1 The fittings shall be made from flat-rolled steel, such asin Specification A 240/A 240M. The flat rolled steel shall be inthe solution annealed condition unless other heat treat condi-tions are agreed upon by the manufacturer and the purchaser.The fittings shall be formed by a h
20、ot or cold process, andwelded by a shielded welding process with or without theaddition of filler metal.5.2 Fittings shall be furnished clean and free of scale.5.3 Welding:5.3.1 The joints shall be full penetration double-welded orsingle-welded butt joints employing fusion-welding processeswith or w
21、ithout the addition of filler metal as defined underDefinitions, ASME Boiler and Pressure Vessel Code, SectionIX. This specification makes no provision for any difference inweld quality requirements regardless of the weld joint-typeemployed (single or double) in making the weld. Weldingprocedures an
22、d welding operators shall be qualified in accor-dance with ASME Boiler and Pressure Vessel Code, SectionIX.5.3.2 For fittings employing multiple passes, the root-passmay be made without the addition of filler metal.5.3.3 The alloy content (chromium, nickel, molybdenum,columbium, and tantalum) of the
23、 deposited weld metal shallconform to that required of the base metal or for equivalentweld metal as given in the AWS filler metal specification A5.4or A5.9, except that, when welding on Types 304L base metal,the deposited weld metal shall correspond, respectively, toAWS Types E308L (ER308L) and, wh
24、en welding on Type 321base metal, the weld metal shall correspond to AWS TypesE347 (ER347 or ER321).6. Chemical Composition6.1 The steel shall conform to requirements of chemicalcomposition for the respective material prescribed in Table 3and Table 4.6.2 The steel shall not contain any unspecified e
25、lements forthe ordered grade to the extent that it conforms to theTABLE 1 Common Tubular Fittings Sizes, Outside DiameterAin. mm in. mm3 76 1234 325312 90 14 3554 100 16 405412 115 18 4606 150 20 510658 170 24 6108 205 30 760858 220 36 91510 255 40 10151034 275 42 107012 305 48 1220AOther sizes may
26、be furnished provided they comply with all other requirementsof this specification.TABLE 2 Common Tubular Fittings Nominal ThicknessesAin. or gage in. mm16 gage 0.062 1.614 gage 0.078 2.012 gage 0.109 2.811 gage 0.125 3.210 gage 0.140 3.68 gage 0.172 4.4316 in. 0.187 4.814 in. 0.250 6.4516 in. 0.312
27、 8.038 in. 0.375 9.512 in. 0.500 12.5AOther thicknesses may be furnished provided they comply with all otherrequirements of this specification.TABLE 3 Chemical RequirementsNOTEWhere an ellipsis (.) appears in this table, there is no requirement.Composition, %Grade UNSDesigna-tionACarbon,maxBMan-gane
28、se,maxPhos-phorus,maxSulfur,maxSilicon,maxChromium Nickel Molybdenum Tita-niumColum-bium plusTantalumNitro-gen,maxTP 304L S30403 0.030 2.00 0.045 0.030 1.00 18.020.0 8.012.0 . . . . . . . . . 0.10TP 316L S31603 0.030 2.00 0.045 0.030 1.00 16.018.0 10.014.0 2.003.00 . . . . . . 0.10TP 317L S31703 0.0
29、30 2.00 0.045 0.030 1.00 18.020.0 11.015.0 3.04.0 . . . . . . 0.10TP 321 S32100 0.08 2.00 0.045 0.030 1.00 17.019.0 9.012.0 . . .C. .TP 347 S34700 0.08 2.00 0.045 0.030 1.00 17.019.0 9.012.0 . . . . . .D.ANew designation established in accordance with Practice E 527 and SAE J1086.BThe carbon analysi
30、s shall be reported to the nearest 0.01 % except for the low carbon (0.030) types, that shall be reported to the nearest 0.001 %.CTi = 5X(C+N) 0.70.DThe columbium plus tantalum content shall be not less than ten times the carbon content and not more than 1.10 %.A 774/A 774M 062requirements of anothe
31、r grade for which that element is aspecified element having a required minimum content.6.3 Mill certificates of analysis of each heat of steel shall befurnished on request.7. Mechanical Properties7.1 The material used in making these fittings shall conformto the test requirements listed in Table 5 f
32、or the specified grade.Mechanical tests made on the sheet or plate by the manufac-turer shall qualify the sheet or plate material.7.2 Mechanical properties of fittings made to this specifica-tion are not verified unless specific tests and limits have beenagreed upon between the purchaser and manufac
33、turer.8. Heat Treatment8.1 Heat treatment is not required (see 16.1).9. Permissible Variations in Nominal Dimensions9.1 Refer to MSS SP 43 for tolerances for fittings coveredby this specification. For fittings not covered in MSS SP 43(wyes and laterals) acceptance limits must be agreed uponbetween t
34、he purchaser and manufacturer.10. Hydrostatic Tests10.1 Hydrostatic testing of the fittings is not required by thisspecification.11. Surface Quality11.1 See Specification A 960/A 960M.11.2 When the removal of a surface discontinuity reducesthe wall thickness below 8712 % of the specified nominal wal
35、lthickness at any point, the fitting shall be subject to rejection orto repair as provided in Section 14.12. Inspection12.1 The manufacturer shall afford the purchasers inspectorall reasonable facilities necessary to satisfy him that thematerial is being furnished in accordance with the specifica-ti
36、on. Mill inspection by the purchaser shall not interfereunnecessarily with the manufacturers operations. All tests andinspections shall be made at the place of manufacture, unlessotherwise agreed to.12.2 Other tests, when required by agreement, shall be madefrom material of the lots covered in the o
37、rder.NOTE 1A lot shall consist of all fittings of the same type, size, andwall thickness, manufactured from one heat of material and using one lotnumber of electrode or one heat of weld wire.13. Repair of Defects13.1 Injurious defects that are deeper than the minimumspecified in Section 12 may be re
38、paired with the approval ofthe purchaser. Such defects shall be entirely removed by eitherchipping, machining, or grinding before welding. Reweldingshall be in accordance with 5.3 of this specification.14. Rejection and Rehearing14.1 Material that fails to conform to the requirements ofthis specific
39、ation may be rejected. Rejection should be reportedto the producer or supplier promptly and in writing. In case ofdissatisfaction with the results of the test, the producer orsupplier may make claim for rehearing.14.2 Fittings that develop defects in shop working orapplication operations may be reje
40、cted. Upon rejection themanufacturer shall be notified in writing.15. Certification15.1 See Specification A 960/A 960M.16. Product Marking16.1 Each fitting shall be legibly marked with the manufac-turers name or brand, the schedule number or pressure class orthickness, the specified size, the specif
41、ication number, thegrade of material listed in Table 1, the heat number ormanufacturers heat identification, and the letters “HT-O” toindicate that there has been no heat treating after welding orforming.NOTE 2For purposes of identification marking, the manufacturer isconsidered the organization tha
42、t certifies the piping component complieswith the specification.TABLE 4 Product Analysis TolerancesAElement Tolerance Over the MaximumLimit or Under the Minimum LimitCarbon 0.005Manganese 0.040Phosphorus 0.010Sulfur 0.005Silicon 0.050Chromium 0.200Nickel 0.100Molybdenum 0.100Nitrogen 0.005AThis tabl
43、e does not apply to heat analysis.TABLE 5 Mechanical Test RequirementsTypeAUNSDesignationTensileStrengthYieldStrengthElongation in2in.50 mm,min, %Hardness, maxBksi MPa ksi MPa Brinell RockwellB304L S30403 70-95 485-655 25 170 40.0 183 88316L S31603 70-95 485-655 25 170 40.0 217 95317L S31703 75-100
44、515-690 30 205 35.0 217 95321 S32100 75-100 515-690 30 205 40.0 217 95347 S34700 75-100 515-690 30 205 40.0 202 92AUnless otherwise indicated, a grade designation originally assigned by the American Iron and Steel Institute (AISI).BEither Brinell or Rockwell B Hardness is permissible.A 774/A 774M 06
45、316.2 The specification year of issue and revision letter, ifany, are not required for product marking.17. Packaging17.1 The manufacturer shall box, crate, or package in securelifts or bundles to ensure safe delivery. If specified, the endsshall be protected with wooden or plastic plugs. Specialpack
46、aging requiring extra operations other than those abovemust be specified by the purchaser.18. Keywords18.1 austenitic stainless steel; corrosive service applica-tions; pipe fittings-steel; piping applications; stainless steelfittings; temperature service applications-lowSUPPLEMENTARY REQUIREMENTSSup
47、plementary requirements shall not be considered unless specified in the order, in which event,any or all of the supplementary tests specified in Specification A 960/A 960M shall be made at theplace of manufacture, unless otherwise agreed upon. The tests specified shall be witnessed by thepurchasers
48、inspector before shipment of material if so specified in the order.SUMMARY OF CHANGESCommittee A01 has identified the location of selected changes to this specification since the last issue,A 774/A 774M 02, that may impact the use of this specification. (Approved March 1, 2006)(1) Changed “Ti”to“Ti”
49、inNoteCofTable 3.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of 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 f
