ASTM F835-2016 Standard Specification for Alloy Steel Socket Button and Flat Countersunk Head Cap Screws《合金钢凹圆头螺钉和平沉头螺钉的标准规格》.pdf

1、Designation: F835 16Standard Specification forAlloy Steel Socket Button and Flat Countersunk Head CapScrews1This standard is issued under the fixed designation F835; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last

2、revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () 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 requiremen

3、ts for quenchedand tempered alloy steel hexagon socket button (SBHCS)0.060 through 0.625 thread sizes and flat countersunk (SFHCS)0.060 through 1.5 thread sizes head cap screws having materialproperties for high-strength requirements.1.2 Fasteners meeting this specification are intended forshear-typ

4、e applications and have tensile requirements rangingfrom 122 to 150 ksi.1.3 The values stated in inch-pound units are to be regardedas standard. No other units of measurement are included in thisstandard.1.4 The hazard statement applies only to the test methodsection, Section 11, of this specificati

5、on. This standard doesnot purport to address all of the safety concerns, if any,associated with its use. It is the responsibility of the user of thisstandard to establish appropriate safety and health practicesand determine the applicability of regulatory limitations priorto use.2. Referenced Docume

6、nts2.1 ASTM Standards:2A751 Test Methods, Practices, and Terminology for Chemi-cal Analysis of Steel ProductsD3951 Practice for Commercial PackagingE3 Guide for Preparation of Metallographic SpecimensE18 Test Methods for Rockwell Hardness of Metallic Ma-terialsE112 Test Methods for Determining Avera

7、ge 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 Discontinuities of Bolts,Screws, and

8、Studs, Inch and Metric Series2.2 ASME Standards:3B18.3 Socket Cap, Shoulder and Set ScrewsInch SeriesB18.24 Part Identifying Number (PIN) Code System Stan-dard for B18 Fastener Products3. Ordering Information3.1 Orders for material under this specification shall includethe following:3.1.1 Quantity (

9、number of screws).3.1.2 Dimensions, including nominal thread designation,thread pitch, and nominal screw length (inches). A standardpart number may be used for this definition.3.1.3 Name of the screw: SBHCS or SFHCS.3.1.4 Coating, if required. If a protective finish other thanblack oxide is required

10、, it must be specified on the order orproduct standard.3.1.5 Lot testing, if required (see 10.3).3.1.6 Certification, if required (see 14.1).3.1.7 ASTM designation and year of issue.3.1.8 Any special requirements.3.1.9 For establishment of a part identifying system, seeASME B18.24.3.2 Example1000 pi

11、eces 0.250 20 0.375 SBHCS lottensile test. ASTM F835XX.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 accordance withTest Methods E112 shall prevail.

12、4.2 Screws shall be hot or cold upset or extruded, or both.1This 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 Dec. 1, 2016. Published January 2017. Or

13、iginallyapproved in 1986. Last previous edition approved in 2013 as F835 13. DOI:10.1520/F0835-16.2For 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 Docu

14、ment Summary page onthe ASTM website.3Available from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Three Park Ave., New York, NY 10016-5990, http:/www.asme.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr H

15、arbor 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 theDevelopment of International Standards, Guides and Recommend

16、ations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.14.3 Unless otherwise specified, threads shall be rolled fordiameters through 0.625 in. and for screw lengths through 4 in.For diameters and lengths other than this, threads may berolled, cut or ground.4.4 Scre

17、ws shall be heat treated by quenching in oil fromabove the transformation temperature and then tempering byreheating to at least 650F to be within the hardness rangespecified in Table 1.4.4.1 The minimum tempering temperature may be verifiedby submitting screws to 635F for 30 min at temperature. The

18、average cross-section hardness of three readings on the screwbefore and after retempering shall not differ by more than 20DPH.4.5 When protective or decorative coatings are applied tothe screws, precautions as required by the coatings shall betaken to prevent embrittlement.5. Chemical Composition5.1

19、 The chemical composition of the screw material shallconform to the heat analysis specified in Table 2.5.2 One or more of the following alloying elements,chromium, nickel, molybdenum, or vanadium, shall be presentin the steel in sufficient quantity to ensure the specific strengthproperties are met a

20、fter 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 Steel to which bismuth, selenium, tellurium, or lead hasbeen added intentionally shall not be permitted.5.4 Mater

21、ial analysis may be made by the purchaser fromfinished products and the chemical composition thus deter-mined shall conform to the requirements specified for theproduct analysis in Table 2.6. Mechanical Properties6.1 The finished screws shall conform to the mechanicalrequirements specified in Table

22、1.6.2 Screws having a nominal length equal to or greater than3 diameters shall be tested full size and shall conform to thefull-size tensile requirements specified in Table 3. Tensilefailures through the head are acceptable provided the loadrequirements are satisfied.6.3 Screws having a nominal thre

23、ad diameter-length com-bination as specified in 6.2 and a breaking load exceeding200 000 lb preferably shall be tested full size and shall meet thefull-size tensile properties in Table 3. When equipment ofsufficient capacity for such tests is not available or if excessivelength of the screws makes f

24、ull-size testing impractical, stan-dard round machined specimens may be used that shall meetthe machined test specimen tensile properties in Table 1.Ifdiscrepancy between full-size and machined specimen results,full-size tests shall be used as the referee method to determineacceptance.6.4 Screws tha

25、t are too short (lengths less than three timesnominal size) or that have insufficient threads for tensiontesting shall not be subject to tension tests but shall conform tothe hardness (minimum and maximum) requirements of Table1.6.5 All screws, regardless of size, shall conform to thehardness specif

26、ied in Table 1. Hardness shall be met anywhereon the cross section through the threaded portion one diameterfrom the screw point.7. Other Requirements7.1 Decarburization:7.1.1 There shall be no evidence of carburization or grossdecarburization on the surfaces of the heat-treated screws whenmeasured

27、in accordance with 11.5.7.1.2 The depth of partial decarburization shall be limited tothe values in Table 4 when measured as shown in Fig. 1, andin accordance with 11.5.7.2 EmbrittlementCoated screws shall withstand the em-brittlement test in accordance with 11.4 without showingindications of discon

28、tinuities. The loading shall be calculatedwith minimum screw tensile requirements.8. Dimensions8.1 Unless otherwise specified, the dimensions shall con-form to the requirements of ASME B 18.3.9. Workmanship, Finish, and Appearance9.1 Surface FinishThe screws shall have a black (thermalor chemical) o

29、xide finish, unless otherwise specified.9.2 Surface Discontinuities:9.2.1 The surface discontinuities for these products shallconform to Specification F788 and the additional limitationsspecified herein.TABLE 1 Mechanical RequirementsNominal Thread Size, in.0.500 andsmallerOver 0.500Full-size Screws

30、:Tensile, min, ksi 145 135Machined Test Specimen:Yield strength at 0.2 % offset, min, ksiA153Tensile strength, min, ksiA170Elongation in 4 D,min,%A8Reduction of area, min, %A35Product Hardness:Rockwell C 3944 3744Vickers DPH 382434 363434ANot applicable.TABLE 2 Chemical RequirementsElementCompositio

31、n, %HeatAnalysisProductAnalysisCarbon 0.30 to 0.48 0.28 to 0.50Phosphorus, max 0.035 0.040Sulfur, max 0.040 0.045Alloying elements see 5.2 see 5.2F835 1629.2.2 Forging defects that connect the socket to the periph-ery of the head are not permissible. Defects originating on theperiphery and with a tr

32、averse indicating a potential to intersectare not permissible. Other forging defects are permissible,provided those located in the bearing area, fillet and topsurfaces shall not have a depth exceeding 0.03 D or 0.005 in.,whichever is greater. For peripheral discontinuities, the maxi-mum depth may be

33、 0.06 D not to exceed 0.040 in. (seeFig. 2).9.2.3 Forging defects located in the socket wall within 0.1times the actual key engagement, T, from the bottom of thesocket are not permissible. Discontinuities located elsewhere inthe socket shall not have a length exceeding 0.25 T or amaximum depth of 0.

34、03 D not to exceed 0.005 in. (seeFig. 3).9.2.4 Seams in the shank shall not exceed a depth of 0.03 Dor 0.008 in., whichever is greater.9.2.5 No transverse discontinuities shall be permitted in thehead-to-shank fillet area.9.2.6 Threads shall have no laps at the root or on the flanks,as shown in Fig.

35、 4. Laps are permitted at the crest (Fig. 4c) thatdo not exceed 25 % of the basic thread depth and on the flanksoutside the pitch cylinder. Longitudinal seams rolled beneaththe root of the thread and across the crests of cut threads areacceptable within the limits of 9.2.4.9.2.7 Quench cracks of any

36、 depth, any length, or in anylocation are not permitted.10. Number of Tests10.1 The requirements of this specification shall be met incontinuous mass production for stock, and the manufacturershall make sample inspections to ensure that the productconforms to the specified requirements. Additional t

37、ests ofindividual shipments of material are not ordinarily contem-plated.Arecord of individual heats of steel in each test lot shallbe maintained. The container shall be coded to permit identi-fication of the lot.10.2 When specified in the order, the manufacturer shallfurnish a test report certified

38、 to be the last complete set ofmechanical tests for each stock size in each shipment.10.3 When additional tests are specified on the purchaseorder, a lot, for purposes of selecting test samples, shall consistTABLE 3 Minimum Ultimate Tensile LoadsThread Size Stress Area, in.2Button and CountersunkHea

39、ds, Tensile Load,min lbACoarse Fine Coarse FineCoarseThreadSeriesFine ThreadSeries. . . 0.060-80 . . . 0.00180 . 2600.073-64 0.073-72 0.00263 0.00278 380 4000.086-56 0.086-64 0.00370 0.00394 540 5700.099-48 0.099-56 0.00487 0.00523 710 7600.112-40 0.112-48 0.00604 0.00661 880 9600.125-40 0.125-44 0.

40、00796 0.00830 1150 12000.138-32 0.138-40 0.00909 0.01015 1320 14700.164-32 0.164-36 0.0140 0.01474 2030 21400.190-24 0.190-32 0.0175 0.0200 2540 29000.250-20 0.250-28 0.0318 0.0384 4610 52750.3125-18 0.3125-24 0.0524 0.0580 7600 84500.375-16 0.375-24 0.0775 0.0878 11 200 127000.4375-14 0.4375-20 0.1

41、063 0.1187 15 400 170000.500-13 0.500-20 0.1419 0.1599 20 600 232000.625-11 0.625-18 0.226 0.258 30 500 345000.750-10 0.750-16 0.334 0.373 45 100 507000.875-9 0.875-14 0.462 0.509 62 400 692001.000-8 1.000-12 0.606 0.663 81 800 904001.125-7 1.125-12 0.763 0.858 103 000 1164001.250-7 1.250-12 0.969 1

42、.073 131 000 1460001.375-6 1.375-12 1.155 1.315 156 000 1790001.500-6 1.500-12 1.405 1.581 190 000 215000ABecause of the head critical configuration of these parts, the full size tensile loads are based on 80 % of the minimum heat treated material strength (180 ksi for sizes0.500 in. and smaller and

43、 170 ksi for sizes larger than 0.500 in.) and the stress areas for coarse thread screws.TABLE 4 Decarburization LimitsThreads/in.ThreadHeight, hs0.75 hsfromRoot toCrest, min0.1 hsatRoot, max48 0.013 0.010 0.00144 0.014 0.011 0.00140 0.015 0.011 0.00236 0.017 0.013 0.00232 0.019 0.014 0.00228 0.022 0

44、.017 0.00224 0.026 0.020 0.00320 0.031 0.023 0.00318 0.034 0.026 0.00316 0.038 0.029 0.00414 0.044 0.033 0.00413 0.047 0.035 0.00512 0.051 0.038 0.00511 0.056 0.042 0.00610 0.061 0.046 0.0069 0.068 0.051 0.0078 0.077 0.058 0.0087 0.088 0.066 0.0096 0.102 0.077 0.010F835 163of all screws offered for

45、inspection at one time of one diameterand length. From each lot, the number of samples for eachrequirement shall be as follows:Number of Pieces in LotNumber ofSamples800 and less 1Over 800 to 8000, incl 2Over 8000 to 22 000, incl 3Over 22 000 510.4 Should any sample fail to meet the requirements of

46、aspecified test, double the number of samples from the same lotshall be retested for the requirement(s) in which it failed.All ofthe additional samples shall conform to the specification or thelot shall be rejected.11. Test Methods11.1 Chemical analysis shall be conducted in accordancewith Test Meth

47、ods, Practices, and Terminology A751.11.2 Tensile properties shall be determined in accordancewith Test Methods F606/F606M.11.3 Hardness shall be determined in accordance with TestMethods E18.11.4 Embrittlement tests shall be conducted in accordancewith Test Methods F606/F606M except no wedge angle

48、shallbe used. The applied tension shall be axial. Tightening shall beapplied using a zinc plated nut with a minimum proof strengthof 150 000 psi tightened against a hardened washer and not bytorque applied through the recess. For screws too short toperform a torque-tension test, tightening values sh

49、all be calcu-lated using the formula: Torque5KdP where K is 0.22 if dry, dis the nominal diameter and P is 80% of the tabulatedminimum tensile value in this standard.11.5 Decarburization and carburization tests shall be con-ducted as follows:FIG. 1 Decarburization LimitsFIG. 2 Head and Body Discontinuity LimitationsFIG. 3 Socket Discontinuity LimitationsF835 16411.5.1 Section the thread area of the bolt longitudinallythrough the axis, mount, and polish it in accordance withPractice E3. Take measurements (1) at the minor diameter inthe center of the thread ridge,