SPECIFICATION FOR
CARBON AND ALLOY STEEL NUTS FOR BOLTS FOR HIGH-PRESSURE AND
HIGH-TEMPERATURE SERVICE
SA-194/SA-194M
SA-194/SA-194M1998SECTION II
E18Test Methods for Rockwell Hardness and Rockwell Superficial Hardness of Metallic Materials
E381Method of Macroetch Testing,Inspection,and Rating Steel Products,Comprising Bars,Billets, Blooms,and Forgings
2.2American National Standards:
B1.1Unified Screw Threads
B1.2Gages and Gaging for Unified Screw Threads
B18.2.2Square and Hex Nuts
2.3AIAG Standard:
AIAG B-502.00Primary Metal Identification Tag Appli-cation Standard
3.Terminology
3.1Descriptions of Terms Specific to This Standard:
3.1.1Lot:
3.1.1.1Unless otherwi specified(e3.1.1.2),
a lot is the quantity of nuts of a single nominal size and grade produced by the same manufacturing process.
3.1.1.2When Supplementary Requirement S6is invoked on the purcha order,the following definitions
of a lot shall apply:
For Grade8Nuts—The quantity of all the nuts
of a single nominal diameter and grade made from the same heat of steel and made by the same manufacturing process.
For All Other Grade Nuts(e7.2and7.1.2.1)—
All the nuts of a single nominal diameter and grade made from the same heat number and heat treated in
the same batch if batch-type heat treating equipment
is ud or heat treated in the same continuous run of
not more than8h under the same conditions if continu-ous-type heat treating equipment is ud.
佛国
3.1.2Type:
3.1.2.1For Grade8Nuts—Variations within
the grade designated by a letter and differentiated by chemistry and by manufacturing process.
3.1.2.2For Grade6Nuts—Variations within
the grade designated by the letter F as differentiated
by chemical additions made for machineability.
3.1.3Series—The dimensional relationship and geometry of the nuts as described in ANSI B18.2.2.
2724.Ordering Information
4.1The inquiry and order for material under this specification shall include the following as required to describe the material adequately:
4.1.1Specification designation and grade,
4.1.2Quantity,number of pieces,
4.1.3Dimensions(e Section9),
4.1.4Options in accordance with6.1,7.2.2.1,9.1, 9.2,10.3,11,12,and13,and
4.1.5Supplementary Requirements,if any.
5.Manufacture(Process)
5.1The steel shall be produced by any one of the following process:open-hearth,basic-oxygen,electric-furnace,or vacuum-induction melting(VIM).The pri-mary melting method may incorporate parate degass-ing or refining.The molten steel may be vacuum-treated prior to or during pouring of the ingot or strand casting.The basic-oxygen process shall be limited to steels containing not over6%chromium.
5.1.1Quality—To ensure soundness,ferritic steel bars shall be tested in accordance with Method E381, or other suitable method as agreed upon between the purchar and the producer.Either the bar producer or the nut producer,as agreed upon between them,shall perform the test.Quality control procedures shall be sufficient to demonstrate that the testing was performed and that the results were acceptable.A bar lot consisting of one heat or10000lbs,whichever is smaller,shall be reprente
d by a minimum of one macroetch.Visual examination of transver ctions shall show no imper-fections wor than the macrographs of Method E381 S4-R4-C4or equivalent as agreed upon.Distinct zones of solidification shall not be prent.
5.2Stainless steels for all types of Grade6and8 nuts shall be made by one of the following process:
5.2.1Electric-furnace(with parate degassing and refining optional),
5.2.2Vacuum induction furnace,or
5.2.3Either of the above followed by electroslag remelting,or consumable-arc remelting.
5.3The steel producer shall exerci adequate control to eliminate excessive unhomogeneity,nonmetallics, pipe,porosity,and other defects.
PART A—FERROUS MATERIAL SPECIFICATIONS SA-194/SA-194M
5.4Grades1and2nuts shall be hot or cold forged,
or shall be machined from hot-forged,hot-rolled,or cold-drawn bars.
5.4.1All Grade1and2nuts made by cold forging
or by machining from cold-drawn bars shall be stress-relief annealed at a temperature of at least1000°F [538°C].
5.4.2Grade1and2nuts made by hot forging or
by machining from hot-forged or hot-rolled bars need
not be given any stress relief annealing treatment.
5.5Grades2HM,2H,3,4,6,6F,7,7M,and16 nuts shall be hot or cold-forged or shall be machined from hot-forged,hot-rolled,or cold-drawn bars and shall be heat treated to meet the required mechanical properties.However,nuts machined from heat-treated bars need not be reheat treated.See Supplementary Requirement S4for nuts to be ud in low-temperature applications(Specification A320/A320M).The grades of nuts shall be reheated above the critical range
of the steel,quenched in a suitable medium,and then tempered at a temperature not less than the following:
Minimum Tempering嗜睡
Grade and Type Temperature,°F[°C]
2H850[455]
2HM1150[620]
31050[565]
41100[595]
6and6F1100[595]
7and7M1100[595]
161200[650]
5.5.1Grade6and6F nuts shall be tempered for
a minimum of1h at the temperature.
5.6Grades8,8C,8M,8T,8F,8P,8N,8MN,8R,
8S,8LN,8MLN,and8MLCuN nuts shall be hot or cold forged,or shall be machined from hot-forged,hot-rolled or cold-drawn bars.
5.7Grades8A,8CA,8MA,8TA,8FA,8PA,8NA,
8MNA,8RA,8SA,8LNA,8MLNA,and8MLCuNA nuts shall be hot or cold-forged or shall be machined from hot-forged,hot-rolled,or cold-drawn bars and the nuts shall subquently be carbide-solution treated by heating them for a sufficient time at a temperature to dissolve chromium carbides followed by cooling at a rate sufficient to prevent reprecipitation of the carbides.
6.Chemical Composition
6.1An analysis of each heat of steel ud for nuts shall be made by the manufacturer during the pouring
游戏名字伤感273of the steel.For strand cast materials,the requirements of8.2and8.3of Specification A788shall be met. Should the purchar deem it necessary to have the transition zone of two heats quentially cast discarded, the purchar shall invoke Supplementary Requirement S3of Specification A788.
6.2The heat analysis of the nut materials shall conform to the chemical composition requirements for
the grade ordered as specified in Table1.Nuts that are normally furnished from stock are not identified by heat number,and thus heat analysis cannot normally be reported to the purchar.(See Supplementary Re-quirement S2.)Supplementary Requirement S6is pro-vided for u when heat analysis control is required.
6.3Steels with added lead shall not be ud.
6.4Product analys may be made by the purchar from a sample nut lected by the purchar or the purchar’s reprentative from each item in the ship-ment which shall meet the product analysis requirements for the grade ordered in Table 1.Product analysis tolerances are found in Tables5and6of Specification A29/A29M,and Table1of Specification A484/A 484M.
6.5A starting material that specifically requires the addition of any element beyond tho listed in Table 1is not permitted.This does not preclude the u of deoxidizers.
通草的作用6.6Chemical analysis shall be performed in accord-ance with Test Methods A751.他人眼中的自己
7.Mechanical Requirements
7.1Hardness Test:
7.1.1Requirements:
7.1.1.1All nuts shall be capable of meeting the hardness requirements specified in Table2.
7.1.1.2Sample nuts of Grades1,2,2H,2HM, 3,4,7,7M,and16which have been given the treatment described in7.1.5.2shall meet the minimum hardness specified in Table2.
7.1.2Number of Tests(Grades1,2,2H,3,4,7, and16and all types of Grade6):
7.1.2.1Tests on the number of sample nuts in accordance with the following table shall be performed in accordance with7.1.5.1by the manufacturer follow-ing all production heat treatments:
SA-194/SA-194M1998SECTION II
Lot Size Samples
Up to8001
801to80002
道德经第十一章8001to220003
Over220005
7.1.2.2In addition,a hardness test shall be performed by the manufacturer in accordance with 7.1.5.2on one sample nut lected from each nominal diameter and ries from each grade and heat number following completion of all production heat treatments.
7.1.3Number of Tests,Grades2HM and7M:
7.1.3.1The maximum hardness of Grade2HM and7M shall be235HB or99HRB(conversion in accordance with Table2B of Test Methods and Defini-tions A370).Conformance to the maximum hardness shall be insured by testing the hardness of each nut
by Brinell or Rockwell B methods as described in the ctions on Brinell Test,Portable Hardness Test,and Rockwell Test of Test Methods and Definitions A370. Surface preparation for hardness testing shall be in accordance with Test Methods E18.Product which has been100%tested and found acceptable shall have
a line under the“M.”
7.1.3.2In addition,7.1.2.2shall be met.
7.1.4Number of Tests,All Types of Grade8—Tests on the number of sample nuts in accordance with 7.1.2.1shall be performed in accordance with7.1.5.1
by the manufacturer.
7.1.5Test Methods:
7.1.5.1Test1—The manufacturer shall perform
the hardness tests in accordance with Annex A3,Para-graph A3.5.2of Test Methods and Definitions A370.
7.1.5.2Test2—The manufacturer shall perform hardness tests in accordance with7.1.5.1to sample nuts after the following test heat treatment.After com-pletion of all production heat treatments heat the speci-men nuts to the temperatures indicated below for24 h,then slow cool.Test at room temperature.
Temperature
Grade°F[°C]
1850[455]
2,2H,2HM1000[540]
3,4,7,7M1100[590]
161200[650]
7.1.5.3Special Requirement,Grades2HM and
7M—Preparation of Grades2HM and7M nuts for hardness test and the hardness test itlf shall be
274performed with consideration to(1)protect legibility of markings;(2)minimize exterior dimensional changes; and(3)maintain threadfit.
7.2Proof Load Test:
7.2.1Requirements—All nuts shall be capable of withstanding the proof loads specified in Table3. However,nuts manufactured to dimensions and config-urations other than tho covered by ANSI B1.1and B18.2.2are not subject to the proof load test.
7.2.2Number of Tests:
7.2.2.1Tests on the number of sample nuts in accordance with7.1.2.1shall be performed by the manufacturer following all production heat treatments except that,unless proof load testing or Supplementary Requirement S1is specified in the order,nuts which would require a proof load in excess of120000lbf [530kN]may be furnished on the basis of minimum hardness requirements.Proof load testing of nuts requir-ing a proof load of over120000lbf[530kN]is covered in Supplementary Requirement S5.
7.2.3Test Method—The test shall be in accord-ance with Annex A3,Paragraph A3.5.1,of Test Methods and Definitions A370.
7.3Cone Proof Load Test:
7.3.1Requirements—This test shall be performed only when visible surface discontinuities become a matter of issue between the manufacturer and the purchar.The requirements specified in Table4shall be met for the size range1⁄4to11/2in.[6.4to38.1 mm].Nuts not in this size range and all types of Grade8nuts are not subject to this test.Also,nuts manufactured to dimensions and configurations other than tho covered by ANSI B1.1and B18.2.2are not subject to the cone proof l
oad test.
7.3.2Number of Tests—Sample nuts in accord-ance with7.1.2.1shall be tested by the manufacturer.
7.3.3Test Method—The test shall consist of asmbling a hardened cone(e Fig.1)and the nut to be tested on a hardened steel mandrel,and applying the proof load specified in Table4.The mandrel shall conform to the requirements of Annex A3,Paragraph A3.5.1of Test Methods and Definitions A370except that the threads shall be in accordance with ANSI B1.1 of the appropriate thread ries,Class3Afit.The hardened cone shall be as described in Fig.2.The lot shall be considered acceptable if the sample nut with-stands application of the proof load without failure.
PART A—FERROUS MATERIAL SPECIFICATIONS SA-194/SA-194M
8.Retests
8.1Provisions for retests by the purchar and his reprentative are specified in Supplementary Require-ment S3.
9.Dimensions
9.1Nuts shall be hexagonal in shape,and in accord-ance with the dimensions for the hex or heavy hex ries,as required,by ANSI B18.2.2.Unless otherwi specified,the American National Standard Heavy Hex Series shall be ud and nuts shall be either double chamfered or have a machined or forged washer face,
初春小雨
at the option of the manufacturer,and,conform to the angularity requirements of ANSI B18.2.2.
9.2Unless otherwi specified,threads shall be in accordance with ANSI B1.1and shall be gaged in accordance with ANSI B1.2as described in9.2.1 and9.2.2.
9.2.1Nuts up to and including1in.[25.4mm] nominal size shall be UNC Series Class2Bfit.
9.2.2Nuts over1in.[25.4mm]nominal size shall be either UNC Series Class2Bfit or8UN Series Class2Bfit.Unless otherwi specified,the8UN ries shall be furnished.
10.Workmanship,Finish,and Appearance
10.1Nuts shall be free of defects and shall be good commercialfinish.
10.2If visible surface imperfections in size1⁄4thru
11⁄2in.[6.4thru38.1mm]and in any grade other than Grade8become a matter of issue between the manufacturer and the purchar,the cone proof load test described in7.3shall be employed.
10.3If a scale-free brightfinish is required,this shall be specified on the purcha order.行政复议决定书
11.Inspection
11.1The manufacturer shall afford the purchar’s inspector all reasonable facilities necessary to satisfy him that the material is being produced and furnished
in accordance with this specification.Mill inspection
by the purchar shall not interfere unnecessarily with
the manufacturer’s operations.All tests and inspections shall be made at the place of manufacture,unless agreed otherwi.
27512.Rejection
12.1Unless otherwi specified,any rejection bad on tests made in accordance with6.4shall be reported to the manufacturer within30days from the date of tests.
13.Certification
13.1When agreed upon in writing between the manufacturer and the purchar,a certification that the nuts were manufactured and tested in accordance with this specification may be the basis of acceptance of the nuts.
13.2When specified on the order,the manufacturer shall supply a test report showing the results of the mechanical and/or macroetch inspection tests performed in accordance with this specification.The specification designation included on test reports shall include year of issue and revision letter,if any.
13.3When required in the order,the chemical analysis requirements and the minimum tempering temperature for nuts of Grades2H,2HM,3,4,6,6F,7,and7M shall be furnished on the certification.See6.2for heat analysis identification.(See Supplementary Require-ment S2.)
14.Product Marking
14.1All nuts shall bear the manufacturer’s identifica-tion mark.
14.2Nuts shall be legibly marked to indicate the grade and the process of the manufacturer,as prescr
ibed in Table5.
14.3For purpos of identification marking,the manufacturer is considered the organization that certifies the fastener was manufactured,sampled,tested,and inspected in accordance with the specification and the results have been determined to meet the requirements of this specification.
14.4Bar Coding—In addition to the requirements in14.1,14.2,and14.3,bar coding is acceptable as a supplementary identification method.Bar coding should be consistent with AIAG Standard B-502.00.If ud on small items,the bar code may be applied to the box or a substantially applied tag.
15.Keywords
15.1bolting;chemical analysis;marking on fasteners
