1、Designation: F912 11Standard 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 number in parenthese
2、s 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 Department of Defense.1. Scope*1.1 This specification covers the requirements for quenchedand tempered alloy
3、 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 manufacturerfor proper alloy
4、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 thisSpecification.1.4 The haz
5、ard 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 and health practices andd
6、etermine the applicability of regulatory limitations prior touse.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 Test Methods for Determining Average Grain SizeE3
7、84 Test Method for Knoop and Vickers Hardness ofMaterialsF606 Test Methods for Determining the Mechanical Prop-erties of Externally and Internally Threaded Fasteners,Washers, Direct Tension Indicators, and RivetsF788/F788M Specification for Surface Discontinuities ofBolts, Screws, and Studs, Inch an
8、d 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 and Studs2.2 ASME Standards:3B18.3 Socket Cap, Shoulder and Set S
9、crew, 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).3.1.2 Dimensions, including nominal thread designatio
10、n,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 designation and year of issue.3.1.7 Any special or s
11、upplemental 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,referee tests on finished screws conducted in accordan
12、ce withTest Methods E112 shall prevail.4.2 The screws may be forged, formed, extruded, machined,or ground to meet the dimensional characteristics and perfor-mance requirements.1This specification is under the jurisdiction of ASTM Committee F16 onFasteners and is the direct responsibility of Subcommi
13、ttee F16.02 on Steel Bolts,Nuts, Rivets and Washers.Current edition approved Nov. 1, 2011. Published November 2011. Originallyapproved in 1986. Last previous edition approved in 2004 as F912 041. DOI:10.1520/F0912-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AST
14、M 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 York, NY 10016-5990, http:
15、/www.asme.org.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 end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1942
16、8-2959, United States.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 specified, thescrews shall be furnished with one of the following st
17、andardsurfaces 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 Protective Coatings:4.5.1 When a protective finish other than as
18、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 minimize embrittlement shall be exercised.5. Chemical Compositio
19、n5.1 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: chro-mium, nickel, molybdenum, or vanadium shall be present inthe steel in sufficient quantity to assure the specific strengthproperties are
20、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, tellurium, orlead has been intentionally added to improve machinabil
21、ityshall 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 set screws when subjected to a torque test inaccordance with 11
22、.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 throughout the screwfrom core to surface.7. Other Requirements7.1 D
23、ecarburization: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 F2328 (Class 3 Product) whenmeasured as described therein.8.
24、 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 Specification F788/F788M and the additionallimitations specifi
25、ed 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 any depth, any length, or in anylocation are not permitte
26、d.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 Chemical analysis shall be conducted in accordancewith T
27、est 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 the test block and the set screw bears against afirm b
28、ase, 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 bymeans of a torque wrench. The screw shall be disassemble
29、dfrom the block and examined for compliance to the require-ments of 6.1.11.3 Hardness shall be determined in accordance with TestMethods F606.11.4 Decarburization and carburization tests shall be con-ducted in accordance with Test Method F2328, Class 3.11.4.1 Screw threads greater than 48 threads pe
30、r in., evalu-ation by the optical method as described Test Method F2328shall determine conformance to specification requirements.12. 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 manuf
31、acture of the materialordered. 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 sh
32、all be made before shipment,and shall be so conducted as not to interfere unnecessarily withthe operation of the works.TABLE 1 Chemical RequirementsNOTE 1Plus alloys in accordance with 5.2.ElementComposition, %Heat Analysis Product AnalysisCarbon 0.30 to 0.48 0.28 to 0.50Phosphorus, max 0.035 0.040S
33、ulfur, max 0.040 0.045F912 11213. 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 manufacturer or supplier, as applicable, shall furnish a testreport or certif
34、icate 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-quirements.14.3 When a certificate of conformance is specified, it s
35、hallinclude a statement certifying the fasteners have been manu-factured, tested, and inspected, and that they conform or do notconform to the requirements of this specification.15. Responsibility15.1 The party responsible for the fastener shall be theorganization that supplies the fastener to the p
36、urchaser.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 requirements are required,they shall be defined at the time of the inq
37、uiry 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,16.2.1.2 Size,16.2.1.3 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
38、theorder), and16.2.1.6 Country of origin.17. Keywords17.1 alloy; set; socket; steelTABLE 2 Torsional Strength RequirementsNominalSizeShortest Nominal Screw Lengths 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.
39、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 0.188 118 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
40、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 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 0001
41、12 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 113SUMMARY OF CHANGESCommittee F16 has identified the location of selected changes to this standard since the last issue (F912041)that may impact the use of this
42、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 always required and not an option).(3) Revised section 7.1.2.(4) Complete
43、 revision of Section 10 (referred to F1470).(5) Revised section 11.3 to Test Methods F606 and added TestMethods F606 to 2.1.(6) Revised section 11.4 decarburization test methods (re-ferred to F2328) and added F2328 to 2.1.(7) Revised 11.4.1.(8) Removed sections 11.4.2 to 11.4.4.2.(9) Section 13, rev
44、ised 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 Figure 2 to Figure 1.(14) Renumbered figure in section 11.2.ASTM International takes no po
45、sition 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 responsibi
46、lity.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 for revision of this standard or for additional standardsand should be addressed to A
47、STM 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 addres
48、s 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 or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).F912 114
