1、Designation: A 194/A 194M 08aEndorsed byManufacturers Standardization Societyof the Valve and Fittings IndustryUsed in USNRC-RDT StandardsStandard Specification forCarbon and Alloy Steel Nuts for Bolts for High Pressure orHigh Temperature Service, or Both1This standard is issued under the fixed desi
2、gnationA 194/A 194M; the number immediately following the designation indicates the 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 rev
3、ision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This specification2covers a variety of carbon, alloy, andmartensitic stainless steel nuts in the size range14 through 4in. and metric M6 through M100 nominal. It also coversaustenitic st
4、ainless steel nuts in the size range14 in. and M6nominal and above. These nuts are intended for high-pressureor high-temperature service, or both. Grade substitutions with-out the purchasers permission are not allowed.1.2 Bars from which the nuts are made shall be hot-wrought.The material may be fur
5、ther processed by centerless grindingor by cold drawing. Austenitic stainless steel may be solutionannealed or annealed and strain-hardened. When annealed andstrain hardened austenitic stainless steel is ordered in accor-dance with Supplementary Requirement S1, the purchasershould take special care
6、to ensure that 8.2.2, SupplementaryRequirement S1, and Appendix X1 are thoroughly understood.1.3 Supplementary requirements (S1 through S8) of anoptional nature are provided. These shall apply only whenspecified in the inquiry, contract, and order.1.4 This specification is expressed in both inch-pou
7、nd 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.1.5 The values stated in either inch-pound units or SI unitsare to be regarded separately as standard. The values stated ineach sy
8、stem are not exact equivalents; therefore, each systemmust be used independently of the other. Combining valuesfrom the two systems may result in nonconformance with thespecification. Within the text, the SI units are shown inbrackets.2. Referenced Documents2.1 ASTM Standards:3A 153/A 153M Specifica
9、tion for Zinc Coating (Hot-Dip) onIron and Steel HardwareA 276 Specification for Stainless Steel Bars and ShapesA 320/A 320M Specification for Alloy-Steel and StainlessSteel Bolting Materials for Low-Temperature ServiceA 962/A 962M Specification for Common Requirementsfor Steel Fasteners or Fastener
10、 Materials, or Both, Intendedfor Use at Any Temperature from Cryogenic to the CreepRangeB 695 Specification for Coatings of Zinc MechanicallyDeposited on Iron and SteelB 696 Specification for Coatings of Cadmium MechanicallyDepositedB 766 Specification for Electrodeposited Coatings of Cad-miumE112 T
11、est Methods for Determining Average Grain SizeF 1940 Test Method for Process Control Verification toPrevent Hydrogen Embrittlement in Plated or CoatedFastenersF 1941 Specification for Electrodeposited Coatings onThreaded Fasteners (Unified Inch Screw Threads (UN/UNR)2.2 American National Standards:4
12、B 1.1 Unified Screw ThreadsB 1.2 Gages and Gaging for Unified Inch Screw ThreadsB 1.13M Metric Screw ThreadsB 18.2.2 Square and Hex NutsB 18.2.4.6M Metric Heavy Hex Nuts3. Terminology3.1 Definitions of Terms Specific to This Standard:1This specification is under the jurisdiction of ASTM Committee A0
13、1 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.22 on Steel Forgings and Wrought Fittings for Piping Applications and BoltingMaterials for Piping and Special Purpose Applications.Current edition approved May 1, 2008. Published June 2008. Originallyap
14、proved in 1936. Last previous edition approved in 2008 as A 194/A 194M08.2For ASME Boiler and Pressure Vessel Code applications see related Specifi-cation SA-194 in Section II of that code.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at servic
15、eastm.org. For Annual Book of ASTMStandards volume 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.1*A Summary of Changes section appears at the
16、 end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.1 Austenitic GradesAll grades with a prefix of “8” or“9”.3.1.2 Ferritic GradesGrades 1, 2, 2H, 2HM, 3, 4, 6, 6F, 7,7M, and 16.3.1.3 LotUnless otherwise specifie
17、d (see Discussion be-low), a lot is the quantity of nuts of a single nominal size andgrade produced by the same manufacturing process.3.1.3.1 DiscussionWhen Supplementary Requirement S5is invoked on the purchase order, the following definitions of alot shall apply:3.1.3.2 For Grade 8 NutsThe quantit
18、y of all the nuts of asingle nominal diameter and grade made from the same heat ofsteel and made by the same manufacturing process.3.1.3.3 For All Other Grade Nuts (see 8.2 and 8.1.2.1)All the nuts of a single nominal diameter and grade made fromthe same heat number and heat treated in the same batc
19、h ifbatch-type heat treating equipment is used or heat treated in thesame continuous run of not more than 8 h under the sameconditions if continuous-type heat treating equipment is used.3.1.4 Type3.1.4.1 For Grade 8 NutsVariations within the gradedesignated by a letter and differentiated by chemistr
20、y and bymanufacturing process.3.1.4.2 For Grade 6 NutsVariations within the gradedesignated by the letter F as differentiated by chemical addi-tions made for machineability.3.1.5 SeriesThe dimensional relationship and geometryof the nuts as described in ANSI B 18.2.2 or B 18.2.4.6M.4. Ordering Infor
21、mation4.1 The inquiry and order for material under this specifica-tion shall include the following as required to describe thematerial adequately:4.1.1 Specification designation, year date, and grade, issuedate and revision letter,4.1.2 Quantity, number of pieces,4.1.3 Dimensions (see Section 9),4.1
22、.4 Options in accordance with 8.2.2.1, 9.1, 9.2, 10.3, and12, and4.1.5 Supplementary Requirements, if any.4.2 CoatingsCoatings are prohibited unless specified bythe purchaser (see Supplementary Requirements S7 and S8).When coated nuts are ordered, the purchaser should takespecial care to ensure that
23、 Appendix X2 is thoroughly under-stood.4.3 See Supplementary Requirement S3 for nuts to be usedin low temperature applications (SpecificationA 320/A 320M).4.4 Proof Load TestingSee Supplementary RequirementS9 for proof load testing of nuts manufactured to dimensionsand configurations other than thos
24、e covered in Tables 3 and 4.5. Common Requirements5.1 Material and fasteners supplied to this specification shallconform to the requirements of Specification A 962/A 962M.These requirements include test methods, finish, thread dimen-sions, marking, certification, optional supplementary require-ments
25、, and others. Failure to comply with the requirements ofSpecification A 962/A 962M constitutes nonconformance withthis specification. In case of conflict between the requirementsof this specification and Specification A 962/A 962M, thisspecification shall prevail.6. Manufacture (Process)6.1 Stainles
26、s steels for all types of Grade 6 and 8 nuts shallbe made by one of the following processes:6.1.1 Electric-furnace (with separate degassing and refiningoptional),6.1.2 Vacuum induction furnace, or6.1.3 Either of the above followed by electroslag remelting,or consumable-arc remelting.6.2 The steel pr
27、oducer shall exercise adequate control toeliminate excessive unhomogeneity, nonmetallics, pipe, poros-ity, and other defects.6.3 Grades 1 and 2 nuts shall be hot or cold forged, or shallbe machined from hot-forged, hot-rolled, or cold-drawn bars.6.3.1 All Grade 1 and 2 nuts made by cold forging or b
28、ymachining from cold-drawn bars shall be stress-relief annealedat a temperature of at least 1000 F 538 C.6.3.2 Grade 1 and 2 nuts made by hot forging or bymachining from hot-forged or hot-rolled bars need not be givenany stress relief annealing treatment.6.4 Grades 2H, 2HM, 3, 4, 6, 6F, 7, 7M, and 1
29、6 nuts shallbe hot- or cold-forged or shall be machined from hot-forged,hot-rolled, or cold-drawn bars and shall be heat treated to meetthe required mechanical properties. These grades shall bereheated above the critical range of the steel, quenched in asuitable medium, and then tempered at a temper
30、ature not lessthan the following:GradeMinimum Tempering Temperature, FC2H 850 4552HM 1150 6203 1050 5654 1100 5956 and 6F 1100 5957 1100 5957M 1150 62016 1200 650Nuts machined from bar heat treated in accordance with thisspecification need not be reheat-treated. For Grade 2HM and7M nuts, a final str
31、ess relief shall be done at or above theminimum tempering temperature after all forming, machining,and tapping operations. This final stress relief may be thetempering operation.6.4.1 Grade 6 and 6F nuts shall be tempered for a minimumof1hatthetemperature.6.5 Grades 8, 8C, 8M, 8T, 8F, 8P, 8N, 8MN, 8
32、R, 8S, 8LN,8MLN, 8MLCuN, and 9C nuts shall be hot or cold forged, orshall be machined from hot-forged, hot-rolled or cold-drawnbars.6.6 Grades 8A, 8CA, 8MA, 8TA, 8FA, 8PA, 8NA, 8MNA,8RA, 8SA, 8LNA, 8MLNA, 8MLCuNA, and 9CA nuts shallbe hot- or cold-forged or shall be machined from hot-forged,hot-roll
33、ed, or cold-drawn bars and the nuts shall subsequentlybe carbide-solution treated by heating them for a sufficient timeat a temperature to dissolve chromium carbides followed bycooling at a rate sufficient to prevent reprecipitation of thecarbides.A 194/A 194M 08a27. Chemical Composition7.1 Each all
34、oy shall conform to the chemical compositionrequirements prescribed in Table 1.8. Mechanical Requirements8.1 Hardness Test:8.1.1 Requirements:TABLE 1 Chemical RequirementsA,B,C,DGradeSymbolMaterialUNSNumberCarbon,%Manga-nese,%Phospho-rus,%Sulfur,E%Silicon,%Chromium,%Nickel,%Molyb-denum,%Tita-nium,%C
35、olum-bium andTanta-lum, %Nitrogen,%OtherElements,%1 carbon 0.15 min 1.00 0.040 0.050 0.40 . . . . . . . . . . . . . . . . . . . . .2, 2HM,and 2Hcarbon 0.40 min 1.00 0.040 0.050 0.40 . . . . . . . . . . . . . . . . . . . . .4 carbon,molyb-denum0.400.50 0.700.90 0.035 0.040 0.150.35 . . . . . . 0.200.
36、30 . . . . . . . . . . . .3 Type 501 0.10 min 1.00 0.040 0.030 1.00 4.06.0 . . . 0.400.65 . . . . . . . . . . . .6 Type 410 S41000 0.15 1.00 0.040 0.030 1.00 11.513.5 . . . . . . . . . . . . . . . . . .6F Type 416 S41600 0.15 1.25 0.060 0.15min1.00 12.014.0 . . . . . . . . . . . . . . . . . .6F Type
37、416SeS41623 0.15 1.25 0.060 0.060 1.00 12.014.0 . . . . . . . . . . . . Selenium,0.15 min7, 7M Type4140/4142/4145,4140H,4142H,4145H0.370.49 0.651.10 0.035 0.04 0.150.35 0.751.20 . . . 0.150.25 . . . . . . . . . . . .8, 8A Type 304 S30400 0.08 2.00 0.045 0.030 1.00 18.020.0 8.011.0 . . . . . . . . .
38、. . . . . .8C, 8CA Type 347 S34700 0.08 2.00 0.045 0.030 1.00 17.019.0 9.012.0 . . . . . . 10 xcarboncontent,min. .8M, 8MA Type 316 S31600 0.08 2.00 0.045 0.030 1.00 16.018.0 10.014.0 2.003.00 . . . . . . . . . . . .8T, 8TA Type 321 S32100 0.08 2.00 0.045 0.030 1.00 17.019.0 9.012.0 . . . 5 x(C+N)mi
39、n -0.70max. . . 0.10 . . .8F, 8FA Type 303 S30300 0.15 2.00 0.20 0.15min1.00 17.019.0 8.010.0 . . . . . . . . . . . . . . .8F, 8FA Type303SeS30323 0.15 2.00 0.20 0.06 1.00 17.019.0 8.010.0 . . . . . . . . . Selenium,0.15 min8P, 8PA Type 305withrestrictedcarbonS30500 0.08 2.00 0.045 0.030 1.00 17.019
40、.0 11.013.0 . . . . . . . . . . . . . . .8N, 8NA Type304NS30451 0.08 2.00 0.045 0.030 1.00 18.020.0 8.011.0 . . . . . . . . . 0.100.168LN,8LNAType304LNS30453 0.030 2.00 0.045 0.030 1.00 18.020.0 8.011.0 . . . . . . . . . 0.100.168MN,8MNAType316NS31651 0.08 2.00 0.045 0.030 1.00 16.018.0 10.013.0 2.0
41、03.00 . . . . . . 0.100.168MLN,8MLNAType316LNS31653 0.030 2.00 0.045 0.030 1.00 16.018.0 10.013.0 2.003.00 . . . . . . 0.100.168R, 8RAFXM19 S20910 0.06 4.06.0 0.045 0.030 1.00 20.523.5 11.513.5 1.503.00 . . . 0.100.30 0.200.40 Vanadium,0.100.308S, 8SA S21800 0.10 7.09.0 0.060 0.030 3.54.5 16.018.0 8
42、.09.0 . . . . . . . . . 0.080.188MLCuN,8MLCuNAS31254 S31254 0.020 1.00 0.030 0.010 0.80 19.520.5 17.518.5 6.06.5 . . . . . . 0.180.22 Copper,0.501.009C, 9CA N08367 N08367 0.030 2.00 0.040 0.030 1.00 20.0-22.0 23.5- 25.5 6.0-7.0 0.18-0.25 Copper0.7516 ChromiumMolyb-denumVanadium0.360.47 0.450.70 0.03
43、5 0.040 0.150.35 0.801.15 . . . 0.500.65 . . . . . . . . . Vanadium,0.250.35AluminumB0.015AThe intentional addition of Bi, Se, Te, and Pb is not permitted except for Grades 6F, 8F, and 8FA, in which Se is specified and required.BTotal aluminum, soluble and insoluble.CMaximum, unless minimum or range
44、 is indicated.DWhere ellipses () appear in this table there is no requirement.EBecause of the degree to which sulfur segregates, product analysis for sulfur over 0.060 % max is not technologically appropriate.FAs described in Specification A 276.A 194/A 194M 08a38.1.1.1 All nuts shall meet the hardn
45、ess requirements speci-fied in Table 2.8.1.1.2 Sample nuts of Grades 1, 2, 2H, 2HM, 3, 4, 7, 7M,and 16 which have been given the treatment described in 8.1.5shall meet the minimum hardness specified in Table 2.8.1.2 Number of Tests (Grades 1, 2, 2H, 3, 4, 7, and 16and all types of Grade 6):8.1.2.1 T
46、ests on the number of sample nuts in accordancewith the following table shall be performed by the manufac-turer following all production heat treatments:Lot Size SamplesUp to 800 1801 to 8000 28001 to 22 000 3Over 22 000 58.1.2.2 In addition, a hardness test shall be performed by themanufacturer in
47、accordance with 8.1.5 on one sample nutselected from each nominal diameter and series from eachgrade and heat number following completion of all productionheat treatments.8.1.3 Number of Tests, Grades 2HM and 7M:8.1.3.1 Each nut shall be tested by Brinell or Rockwellmethods to ensure product conform
48、ance.58.1.3.2 In addition, 8.1.2.2 shall be met.8.1.4 Number of Tests, All Types of Grade 8Tests on thenumber of sample nuts in accordance with 8.1.2.1 shall beperformed by the manufacturer.8.1.5 Test 2In addition to the testing required by 8.1.2.1the manufacturer shall also perform hardness tests o
49、n samplenuts after the following test heat treatment.After completion ofall production heat treatments heat the specimen nuts to thetemperatures indicated below for 24 h, then slow cool. Test atroom temperature.GradeATemperature,F C1 850 4552, 2H, 2HM 1000 5403, 4, 7, 7M 1100 59016 1200 650ANuts intended to be coated with zinc or cadmium (marked in accordance withthe requirements of Supplementary Requirement S8) are not subjected to therequirements of 8.1.5 (Se
