1、Designation: F912 11 (Reapproved 2017)Standard Specification forAlloy Steel Socket Set Screws1This standard is issued under the fixed designation F912; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision. A nu
2、mber in parentheses indicates the year of last reapproval. A superscriptepsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This specification covers the requirements for que
3、nchedand tempered alloy steel socket-set screws (SSS) in nominaldiameters 0.060 through 2 in. having hardnesses 45 to 53 HRC.1.2 These set screws are intended for compression applica-tions only and are not customarily subjected to embrittlementtests. For tensile applications, consult with the manufa
4、cturerfor proper alloy and hardness.1.3 The values stated in inch-pound units are to be regardedas standard. No other units of measurement are included in thisstandard.NOTE 1A complete metric companion to Specification F912 has beendevelopedF912M; therefore, no metric equivalents are shown in thisSp
5、ecification.1.4 The hazard statement pertains only to the test methodsection, Section 11 of this specification. This standard does notpurport to address all of the safety concerns, if any, associatedwith its use. It is the responsibility of the user of this standardto establish appropriate safety an
6、d health practices anddetermine the applicability of regulatory limitations prior touse.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,
7、 Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2A751 Test Methods, Practices, and Terminology for Chemi-cal Analysis of Steel ProductsE3 Guide for Preparation of Metallographic SpecimensE112 Tes
8、t Methods for Determining Average Grain SizeE384 Test Method for Microindentation Hardness of Mate-rialsF606/F606M Test Methods for Determining the MechanicalProperties of Externally and Internally ThreadedFasteners, Washers, Direct Tension Indicators, and RivetsF788 Specification for Surface Discon
9、tinuities of Bolts,Screws, and Studs, Inch and Metric SeriesF1470 Practice for Fastener Sampling for Specified Me-chanical Properties and Performance InspectionF2328 Test Method for Determining Decarburization andCarburization in Hardened and Tempered Threaded SteelBolts, Screws, Studs, and Nuts2.2
10、ASME Standards:3B18.3 Socket Cap, Shoulder and Set Screw, Inch Series4B18.24 Part Identifying Number (PIN) Code System Stan-dard for B18 Fastener Products3. Ordering Information3.1 Orders for material under this specification shall includethe following information:3.1.1 Quantity (number of screws).3
11、.1.2 Dimensions, including nominal thread designation,threads per inch, nominal screw length (inches) and pointconfiguration. A standard part number may be used for thisdefinition.3.1.3 Name of the screw (SSS).3.1.4 Coating, if required. See 4.4.3.1.5 Certification, if required. See 14.1.3.1.6 ASTM
12、designation and year of issue.3.1.7 Any special or supplemental requirements.3.1.8 For establishment of a part identifying system, seeASME B18.24.4. Materials and Manufacture4.1 The screws shall be fabricated from alloy steel made tofine grain practice. In the event of controversy over grain size,1T
13、his specification is under the jurisdiction of ASTM Committee F16 onFasteners and is the direct responsibility of Subcommittee F16.02 on Steel Bolts,Nuts, Rivets and Washers.Current edition approved June 1, 2017. Published June 2017. Originallyapproved in 1986. Last previous edition approved in 2011
14、 as F912 11. DOI:10.1520/F0912-11R17.2For referenced ASTM standards, visit the ASTM website, 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
15、 Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Two Park Ave., New York, NY 10016-5990, http:/www.asme.org.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.*A Summary of Changes section appears at
16、the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for
17、 theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1referee tests on finished screws conducted in accordance withTest Methods E112 shall prevail.4.2 The screws may be forged, formed, extruded, mach
18、ined,or ground to meet the dimensional characteristics and perfor-mance requirements.4.3 Set screws shall be heat treated by quenching in oil fromabove the transformation temperature and then tempered byreheating to meet the hardness range specified in 6.2.4.4 Standard FinishesUnless otherwise speci
19、fied, thescrews shall be furnished with one of the following standardsurfaces as manufactured, at the option of the manufacturer; (1)bright uncoated; (2) thermal black oxide; or (3) chemical blackoxide. Hydrogen embrittlement tests shall not be required forscrews furnished in these conditions.4.5 Pr
20、otective Coatings:4.5.1 When a protective finish other than as specified in 4.4is required, it shall be specified on the purchase order with theapplicable finish specification.4.5.2 When protective or decorative coatings are applied tothe screws, precautions specified by the coating requirementsto m
21、inimize embrittlement shall be exercised.5. Chemical Composition5.1 The chemical composition of the screw material shallconform to the heat analysis specified in Table 1.5.2 One or more of the following alloying elements:chromium, nickel, molybdenum, or vanadium shall be presentin the steel in suffi
22、cient quantity to assure the specific strengthproperties are met after oil quenching and tempering. The steelshall meet the AISI definition of alloy steel, that is, maximumand minimum element content requirement or minimum ele-ment limits specified.5.3 Alloy steel to which bismuth, selenium, telluri
23、um, orlead has been intentionally added to improve machinabilityshall be permitted.5.4 Material analysis may be made by the purchaser fromfinished products and the chemical composition shall conformto the requirements specified for the product analysis in Table1.6. Mechanical Properties6.1 Socket se
24、t screws when subjected to a torque test inaccordance with 11.2 shall withstand application of the testtightening torque specified in Table 2 without evidence of thesocket reaming or the screw bursting.6.2 Socket set screws shall have a hardness of 45 to 53HRC. The hardness limits shall apply throug
25、hout the screwfrom core to surface.7. Other Requirements7.1 Decarburization:7.1.1 There shall be no evidence of gross decarburization ofthe surfaces of the heat-treated screws when measured inaccordance with 11.4.7.1.2 The depth of partial decarburization shall be limited tothe values in Test Method
26、 F2328 (Class 3 Product) whenmeasured as described therein.8. Dimensions8.1 Unless otherwise specified, the product shall conform tothe requirements of ASME B 18.3.9. Workmanship, Finish, and Appearance9.1 Surface Discontinuities:9.1.1 The surface discontinuities for these products shallconform to S
27、pecification F788 and the additional limitationsspecified herein.9.1.2 Processing defects that connect the socket to theperiphery of the screw are not permissible. Defects originatingon the periphery and with a traverse indicating a potential tointersect are not permissible.9.1.3 Quench cracks of an
28、y depth, any length, or in anylocation are not permitted.10. Number of Tests10.1 Practice F1470 shall be used to determine the neces-sary sampling plan and the number of tests that must beperformed to demonstrate all the requirements of this specifi-cation are met for each lot.11. Test Methods11.1 C
29、hemical analysis shall be conducted in accordancewith Test Methods, Practices, and Terminology A751.11.2 For socket strength torque test, the test screw shall beassembled into a tapped hole of 2B tolerance class in a steelblock (see Fig. 1) until the face of the screw is flush with thetop surface of
30、 the test block and the set screw bears against afirm base, such as a hardened screw installed from the oppositeside of the block. The applicable hexagon key bit in accordancewith ASME B 18.3 shall be inserted to the full depth of the setscrew socket and the test torque listed in Table 2 applied bym
31、eans of a torque wrench. The screw shall be disassembledfrom the block and examined for compliance to the require-ments of 6.1.11.3 Hardness shall be determined in accordance with TestMethods F606/F606M.11.4 Decarburization and carburization tests shall be con-ducted in accordance with Test Method F
32、2328, Class 3.11.4.1 Screw threads greater than 48 threads per in., evalu-ation by the optical method as described Test Method F2328shall determine conformance to specification requirements.TABLE 1 Chemical RequirementsNOTE 1Plus alloys in accordance with 5.2.ElementComposition, %Heat Analysis Produ
33、ct AnalysisCarbon 0.30 to 0.48 0.28 to 0.50Phosphorus, max 0.035 0.040Sulfur, max 0.040 0.045F912 11 (2017)212. Inspection12.1 The inspector representing the purchaser, upon reason-able notice, shall have free entry to all parts of the manufac-turers works that concern the manufacture of the materia
34、lordered. The manufacturer shall afford the inspector all rea-sonable facilities to satisfy him that the material is beingfurnished in accordance with this specification. All tests andinspections required by the specification that are requested bythe purchasers representative shall be made before sh
35、ipment,and shall be so conducted as not to interfere unnecessarily withthe operation of the works.13. Rejection and Rehearing13.1 The disposition of nonconforming lots shall be inaccordance with Practice F1470.14. Certification14.1 Upon request of the purchaser in the contract or order,the manufactu
36、rer or supplier, as applicable, shall furnish a testreport or certificate of conformance as specified by the pur-chaser.14.2 When a test report is specified, it shall include the heatnumber and the results of chemical composition, mechanicalproperties, metallurgical requirements, and workmanship re-
37、quirements.14.3 When a certificate of conformance is specified, it shallinclude a statement certifying the fasteners have beenmanufactured, tested, and inspected, and that they conform ordo not conform to the requirements of this specification.15. Responsibility15.1 The party responsible for the fas
38、tener shall be theorganization that supplies the fastener to the purchaser.16. Packaging and Package Marking16.1 Packaging:16.1.1 Unless otherwise specified, packaging shall be inaccordance with the manufacturers practice to prevent damagebefore and during shipment.16.1.2 When special packaging requ
39、irements are required,they shall be defined at the time of the inquiry and order.16.2 Package Marking:16.2.1 Each shipping unit shall include or be plainly markedwith the following information:16.2.1.1 ASTM designation,TABLE 2 Torsional Strength RequirementsNominalSizeShortest Nominal Screw Lengths
40、Subject to Torque Testing for Test TorqueCup and FlatPointsCone andOval PointsHalf DogPointsin.-lb, min0 0.060 0.109 0.125 0.109 1.11 0.073 0.125 0.141 0.125 2.12 0.086 0.125 0.141 0.141 2.13 0.099 0.141 0.156 0.156 6.04 0.112 0.141 0.172 0.156 6.05 0.125 0.156 0.188 0.172 116 0.138 0.172 0.203 0.18
41、8 118 0.164 0.188 0.219 0.203 2310 0.190 0.188 0.250 0.234 4014 0.250 0.250 0.312 0.297 94516 0.312 0.312 0.391 0.359 18338 0.375 0.375 0.438 0.438 317716 0.437 0.438 0.547 0.484 50212 0.500 0.500 0.609 0.547 75058 0.625 0.625 0.766 0.672 146034 0.750 0.750 0.906 0.797 252078 0.875 0.875 1.125 0.984
42、 57501 1.000 1.000 1.266 1.125 8000118 1.125 1.125 1.391 1.188 8000114 1.250 1.250 1.500 1.312 11 000138 1.375 1.375 1.656 1.438 11 000112 1.500 1.500 1.797 1.562 18 100134 1.750 1.750 2.219 1.953 38 0002 2.000 2.000 2.391 2.078 38 000FIG. 1 Typical Torque Test FixtureF912 11 (2017)316.2.1.2 Size,16
43、.2.1.3 Name and brand or trademark of the manufacturer,16.2.1.4 Number of pieces,16.2.1.5 Purchase order number (when specified in theorder), and16.2.1.6 Country of origin.17. Keywords17.1 alloy; set; socket; steelSUMMARY OF CHANGESCommittee F16 has identified the location of selected changes to thi
44、s standard since the last issue(F912041) that may impact the use of this standard.(1) Revised- Section 1, Scope, to clarify “nominal” diameterand remove .000 from 2 in. size.(2) Revised-sections 2.1 and 5.4, to clean up grammar andcorrect names of standards. Removed section 3.1.5 (lot testingis now
45、always required and not an option).(3) Revised section 7.1.2.(4) Complete revision of Section 10 (referred to F1470).(5) Revised section 11.3 to Test Methods F606/F606M andadded Test Methods F606/F606M to 2.1.(6) Revised section 11.4 decarburization test methods (re-ferred to F2328) and added F2328
46、to 2.1.(7) Revised 11.4.1.(8) Removed sections 11.4.2 to 11.4.4.2.(9) Section 13, revised to refer to F1470 and added F1470 to2.1.(10) Revised section 14.1; added sections 14.2 and 14.3.(11) Revised section 16.1.1 and 16.2.1.5.(12) Removed existing Figure 1 and Table 3.(13) Renumbered existing Figur
47、e 2 to Figure 1.(14) Renumbered figure in section 11.2.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
48、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 five years andif not revised, either reapproved or withdrawn. Your comments are invited either
49、for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single o
