1、Designation: A 194/A 194M 07aEndorsed 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 (e) indicates an editorial change since the last re
3、vision 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 s
4、tainless 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 fu
5、rther 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-po
7、und 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. Within the text, theSI uni
8、ts 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 ASTM Standards:3A 153/A 153M Specif
9、ication 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 Faste
10、ner 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-miumE11
11、2 Test 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 Standard
12、s:4B 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
13、 A01 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 March 1, 2007. Published April 2007. Origin
14、allyapproved in 1936. Last previous edition approved in 2007 as A 194/A 194M07.2For 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
15、serviceastm.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 10036.1*A Summary of Changes section appears at the end of this s
16、tandard.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 specified (see Discuss
17、ion 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 quantity of all the n
18、uts 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 batch ifbatch-type
19、 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 chemistry and bymanufa
20、cturing 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 Information4.1 The
21、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),4.1.4 Options in
22、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 Appendix X2 i
23、s thoroughly under-stood.4.3 See Supplementary Requirement S3 for nuts to be usedin low temperature applications (SpecificationA 320/A 320M).5. Common Requirements5.1 Material and fasteners supplied to this specification shallconform to the requirements of Specification A 962/A 962M.These requiremen
24、ts include test methods, finish, thread dimen-sions, marking, certification, optional supplementary require-ments, 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 s
25、pecification and Specification A 962/A 962M, thisspecification shall prevail.6. Manufacture (Process)6.1 Stainless 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 fu
26、rnace, or6.1.3 Either of the above followed by electroslag remelting,or consumable-arc remelting.6.2 The steel producer 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 shallb
27、e machined from hot-forged, hot-rolled, or cold-drawn bars.6.3.1 All Grade 1 and 2 nuts made by cold forging or bymachining 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
28、-rolled bars need not be givenany stress relief annealing treatment.6.4 Grades 2H, 2HM, 3, 4, 6, 6F, 7, 7M, and 16 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 sh
29、all bereheated above the critical range of the steel, quenched in asuitable medium, and then tempered at a temperature 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 he
30、at treated in accordance with thisspecification need not be reheat-treated. For Grade 2HM and7M nuts, a final stress 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 Gra
31、de 6 and 6F nuts shall be tempered for a minimumof1hatthetemperature.6.5 Grades 8, 8C, 8M, 8T, 8F, 8P, 8N, 8MN, 8R, 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,
32、8SA, 8LNA, 8MLNA, 8MLCuNA, and 9CA nuts shallbe hot- or cold-forged or shall be machined from hot-forged,hot-rolled, 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
33、 a rate sufficient to prevent reprecipitation of thecarbides.7. Chemical Composition7.1 Each alloy shall conform to the chemical compositionrequirements prescribed in Table 1.A 194/A 194M 07a2TABLE 1 Chemical RequirementsA,B,CGradeSymbolMaterialUNSNumberCarbon,%Manga-nese,%Phospho-rus,%Sulfur,D%Sili
34、con,%Chromium,%Nickel,%Molyb-denum,%Tita-nium,%Colum-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
35、0.700.90 0.035 0.040 0.150.35 . . . . . . 0.200.30 . . . . . . . . . . . .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.
36、014.0 . . . . . . . . . . . . . . . . . .6F Type416SeS41623 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 0.04
37、5 0.030 1.00 18.020.0 8.011.0 . . . . . . . . . . . . . . .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.
38、045 0.030 1.00 17.019.0 9.012.0 . . . 5 x(C+N)min -0.70max. . .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 305withrestrictedcarbonS30
39、500 0.08 2.00 0.045 0.030 1.00 17.019.0 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
40、.045 0.030 1.00 16.018.0 10.013.0 2.003.00 . . . . . . 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, 8RAEXM19 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
41、 7.09.0 0.060 0.030 3.54.5 16.018.0 8.09.0 . . . . . . . . . 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 ChromiumMoly
42、b-denumVanadium0.360.47 0.450.70 0.035 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 insolu
43、ble.CMaximum, unless minimum or range is indicated.DBecause of the degree to which sulfur segregates, product analysis for sulfur over 0.060 % max is not technologically appropriate.EAs described in Specification A 276.A 194/A 194M 07a38. Mechanical Requirements8.1 Hardness Test:8.1.1 Requirements:8
44、.1.1.1 All nuts shall meet the hardness 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 1
45、6and all types of Grade 6):8.1.2.1 Tests 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
46、 be performed by themanufacturer in 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 Rockw
47、ellmethods to ensure product conformance.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
48、 shall also perform hardness tests on 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
49、, 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 (See Appendix X2).8.1.5.1 Special Requirement, Grades 2HM and 7MPreparation of Grades 2HM and 7M nuts for hardness test andthe hardness test itself shall be performed with consideration to(1) protect legibility of markings; (2) minimize exterior dimen-sional changes; an
