1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS 4A 116:2012Incorporating Corrigendum No. 1Steel pan head bolts(Unified threads), cadmiumplated, for aircraftPublishing and copyright informationThe BSI copyright notice displa
2、yed in this document indicates when the documentwas last issued. The British Standards Institution 2012Published by BSI Standards Limited 2012ISBN 978 0 580 79467 4ICS 49.030.20The following BSI references relate to the work on this standard:Committee reference ACE/12Draft for comment 11/30252412 DC
3、Publication historyFirst published February 1954Second edition February 1956Third edition June 1962Fourth (current) edition March 2012Amendments issued since publicationDate Text affected30 June 2012 This corrigendum incorporates a number of typographicalcorrections including the capitalization of “
4、Unified” and thecorrection of “indentifier” to “identifier” in Clause 8.BS 4A 116:2012 BRITISH STANDARDContentsForeword ii1 Scope 12 Normative references 13 General requirements 24 Material and manufacture 25 Dimensions 26 Screw threads 37 Protective finish 38 Identification and marking 39 Inspectio
5、n procedure 3AnnexesAnnex A (informative) Table for conversion of inches to approximate millimetreequivalents 10Bibliography 11List of figuresFigure 1 Basic dimensions 3Figure 2 Bearing length, clamping length and overall length dimensions 5List of tablesTable 1 Dimensions 4Table 2 Bearing length L,
6、 clamping length M and overall length E6Table A.1 Table for conversion of inches to approximate millimetreequivalents 10Summary of pagesThis document comprises a front cover, an inside front cover, pages i to ii,pages 1 to 12, an inside back cover and a back cover.BRITISH STANDARD BS 4A 116:2012 The
7、 British Standards Institution 2012 iForewordPublishing informationThis British Standard is published by BSI Standards Limited, under licence fromThe British Standards Institution, and came into effect on 31 March 2012. It wasprepared by Technical Committee ACE/12, Aerospace fasteners and fastenings
8、ystems. A list of organizations represented on this committee can be obtainedon request to its secretary.SupersessionThis British Standard supersedes BS 3A 116:1962, which is withdrawn.Information about this documentThis new edition of this British Standard incorporates technical changes only. Itdoe
9、s not represent a full review or revision of the standard, which will beundertaken in due course.CAUTION. BS A 116 bolts have cadmium as a plating material which has beenrestricted and/or banned for use in many countries owing to environmentaland health concerns; they should not be used in new produ
10、ct designs. Localofficials should be consulted about any concerns on using cadmium-platedparts.Presentational conventionsThe provisions of this standard are presented in roman (i.e. upright) type. Itsrequirements are expressed in sentences in which the principal auxiliary verb is“shall”.Commentary,
11、explanation and general informative material is presented insmaller italic type, and does not constitute a normative element.Contractual and legal considerationsThis publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application.C
12、ompliance with a British Standard cannot confer immunity from legalobligations.BRITISH STANDARDBS 4A 116:2012ii The British Standards Institution 20121 ScopeThis British Standard specifies the materials, dimensions, finish and inspectionrequirements for steel pan head bolts with Unified threads, cad
13、mium plated, foraircraft.NOTE 1 The values in British units are to be regarded as the standard. Table A.1provides a ready means of calculating the approximate millimetre equivalents of theinch dimensions. More accurate conversions should be based on the tables in BS 350.NOTE 2 In place of the custom
14、ary, but incorrect, use of the ton as a unit of force,the unit called a ton force (abbreviation tonf) is used in this British Standard. It isthe force which, when acting on a body of mass one ton, gives an acceleration equalto that of standard gravity.2 Normative referencesThe following referenced d
15、ocuments are indispensable for the application ofthis document. For dated references, only the edition cited applies. For undatedreferences, the latest edition of the referenced document (including anyamendments) applies.BS 4A 100:2003, Specification for general requirements for bolts and freerunnin
16、g nuts of tensile strength not exceeding 1 249 MPaBS EN 2133, Cadmium plating of steels with specified tensile strength 1 450MPa, copper, copper alloys and nickel alloysBS S 95, Specification for 112 per cent nickel-chromium-molybdenum steel(90/110 kgf/mm)BS S 102, Specification for carbon-molybdenu
17、m steel (bar for the manufacture offorged bolts only)BS S 105, Specification for carbon steel (bar for the manufacture of forged boltsonly)BS S 114, Manganese-Molybdenum Steel (55/65 tonf/sq in: limiting ruling section212 inches)BS S 116, Specification for aircraft material. 40 Carbon Steel Bright B
18、ars forMachining (55-65 tonf/sq in: limiting ruling section34inch) (Primarily Intendedfor the Manufacture of Machined Bolts)BS S 117, Specification for aircraft material. 1 per cent chromium steel (55/65tonf/sq in: limiting ruling section 1! inch)BS S 147, Specification for 0.5% nickel-chromium-moly
19、bdenum steel bars for themanufacture of forged bolts and forged nutsBS S 148, Specification for low nickel-chromium steel (bar for the manufactureof forged bolts only)BS S 149, Specification for 1.75% nickel-chromium-molybdenum steel bars forthe manufacture of forged bolts and forged nutsBS S 154, S
20、pecification. 212% nickel-chromium-molybdenum steel billets, bars,forgings and parts (880-1080 MPa: limiting ruling section 150 mm)BS S 158, Specification for 1% chromium-molybdenum steel bars for themanufacture of forged bolts and forged nutsDef Stan 03-19, Electro-deposition of cadmiumBRITISH STAN
21、DARD BS 4A 116:2012 The British Standards Institution 2012 13 General requirementsThe bolts shall conform to the relevant requirements of BS 4A 100:2003 inrespect of manufacture, screw threads, anti-corrosion treatment, identificationand marking.4 Material and manufactureThe bolts shall be manufactu
22、red by one of the following methods:a) Machined from bright drawn alloy steel bars that conform to one of thefollowing:1) BS S 952) BS S 1143) BS S 1164) BS S 117; or5) BS S 154.NOTE Material conforming to BS S 96 may be used until stocks are exhausted.b) Forged from alloy steel that conforms to one
23、 of the following:1) BS S 102;2) BS S 105;3) BS S 147;4) BS S 148;5) BS S 149; or6) BS S 158.NOTE Material conforming to BS S 103 may be used until stocks are exhausted.c) In the finally head-treated condition, the mechanical properties of thematerial used for forged bolts shall be as follows:0.1 pe
24、r cent proof stress not less than 43 tonf/in2(664 MPa)Tensile strength not less than 55 tonf/in2(850 MPa)not more than 65 tonf/in2(1003 MPa)Elongation on 5.65area not less than 18%Izod impact value not less than 40 ft lbf (54 J)5 DimensionsAll finished bolts, after the application of the protective
25、finish, shall conform tothe dimensions and tolerances given in Table 1, Table 2, Figure 1 and Figure 2.The clamping length of the bolt shall conform to the dimensions and tolerancesgiven in Table 2, and shall be such that, when a standard nut withoutcountersink or ring gauge without countersink has
26、been screwed on as far aspossible by hand, its leading face is within the distance M from the underside ofthe bolt head. The runout of thread shall not exceed twice the pitch.The nominal length of the bolt shall be the minimum bearing length, L, which isdetermined by the minimum clamping length, M,
27、less two thread pitches.BRITISH STANDARDBS 4A 116:20122 The British Standards Institution 20126 Screw threadsThe bolts shall have Unified threads of the form and class of fit specified in therelevant requirements of BS 4A 100:2003. After coating, the bolt threads shallnot exceed the basic size (maxi
28、mum material condition) for the thread size andclass of fit.7 Protective finishAll bolts shall be coated with cadmium in accordance with Def Stan 03-19 orBS EN 2133.8 Identification and markingBolts shall have the appropriate Unified thread identification applied inaccordance with BS 4A 100:2003, 8.
29、2.2. The British Standard identifier and partnumber (in accordance with Table 2) shall not be applied on the bolts, but shallbe clearly marked on the labels of parcels of bolts together with the batchidentification code. For example, A116-20C is a bolt with thread size 8-32 UNCand bearing length 2.0
30、 inches.9 Inspection procedureThe bolts shall be inspected in accordance with BS 4A 100:2003.Figure 1 Basic dimensions* For bearing length L, clamping length M and overall length E see Table 2.BRITISH STANDARD BS 4A 116:2012 The British Standards Institution 2012 3Table1Dimensions1234567891011121314
31、15161718DecimalnominalthreadsizeNominal threadsizeDiameterofplainportionofshankThreadrunout (2pitch)Length of threadedportion ofshankFDiameterofheadThicknessofheadRa- dius of headRadius underboltheadDepthofchamferSlotWidthDepthABDURGHJmax.min.max.min.ref.max.min.max.min.nom.max.min.max.min.min.max.n
32、om.0.112-40UNC(4)4-40UNC0.11150.10850.0500.3000.1940.1840.0680.0580.0420.0150.0050.0200.0150.0310.0390.0350.138-32UNC(6)6-32UNC0.13750.13450.0630.2770.2520.2420.0820.0720.0460.0150.0050.0300.0200.0390.0480.0430.164-32UNC(8)8-32UNC0.16350.16050.0630.3270.2830.2730.0960.0850.0520.0200.0100.0300.0200.0
33、450.0540.0510.190-32UNF(10)10-32UNF0.18950.18650.0630.3770.3190.3090.1100.0990.0610.0200.0100.0300.0200.0500.0600.0600.250-28UNF(E)1/4-28UNF0.24950.24650.0710.4590.4400.4200.1440.1300.0870.0300.0150.0400.0300.0640.0750.0780.3125-24UNF(G)5/16-24UNF0.31200.30900.0830.4970.5470.5270.1780.1620.0990.0300
34、.0150.0400.0300.0720.0840.095Thisdimensionisanabsoluteminimumassociatedwithmaximumlength,M,andminimumlength,E.Itisnotintendedforuseformanufacturingorinspectionpurposes. Tobemeasuredfromthetopoftheheadtothepointatwhichtheslotbreaksthrough.BRITISH STANDARDBS 4A 116:20124 The British Standards Institut
35、ion 2012Figure 2 Bearing length, clamping length and overall length dimensionsBRITISH STANDARD BS 4A 116:2012 The British Standards Institution 2012 5Table2BearinglengthL,clampinglengthMandoveralllengthENo.4-40UNCNo.6-32UNCNo.8-32UNCNo.10-32UNFPart No.*Lmin.M +0 0.03E +0.040Part No.*Lmin.M +0 0.03E
36、+0.040Part No.*Lmin.M +0 0.03E +0.040PartNo.*Lmin.M +0 0.03E +0.040inininininininininininin12A0.050.1300.4512B0.050.1430.4512C0.050.1430.5012D0.050.1430.551A0.10.1800.501B0.10.1930.501C0.10.1930.551D0.10.1930.602A0.20.2800.602B0.20.2930.602C0.20.2930.652D0.20.2930.703A0.30.3800.703B0.30.3930.703C0.3
37、0.3930.753D0.30.3930.804A0.40.4800.804B0.40.4930.804C0.40.4930.854D0.40.4930.905A0.50.5800.905B0.50.5930.905C0.50.5930.955D0.50.5931.006A0.60.6801.006B0.60.6931.006C0.60.6931.056D0.60.6931.107A0.70.7801.107B0.70.7931.107C0.70.7931.157D0.70.7931.208A0.80.8801.208B0.80.8931.208C0.80.8931.258D0.80.8931
38、.309A0.90.9801.309B0.90.9931.309C0.90.9931.359D0.90.9931.4010A1.01.0801.4010B1.01.0931.4010C1.01.0931.4510D1.01.0931.5011A1.11.1801.5011B1.11.1931.5011C1.11.1931.5511D1.11.1931.6012A1.21.2801.6012B1.21.2931.6012C1.21.2931.6512D1.21.2931.7013A1.31.3801.7013B1.31.3931.7013C1.31.3931.7513D1.31.3931.801
39、4A1.41.4801.8014B1.41.4931.8014C1.41.4931.8514D1.41.4931.9015A1.51.5801.9015B1.51.5931.9015C1.51.5931.9515D1.51.5932.0016A1.61.6802.0016B1.61.6932.0016C1.61.6932.0516D1.61.6932.1017A1.71.7802.1017B1.71.7932.1017C1.71.7932.1517D1.71.7932.2018A1.81.8802.2018B1.81.8932.2018C1.81.8932.2518D1.81.8932.301
40、9A1.91.9802.3019B1.91.9932.3019C1.91.9932.3519D1.91.9932.4020A2.02.0802.4020B2.02.0932.4020C2.02.0932.4520D2.02.0932.5021A2.12.1802.5021B2.12.1932.5021C2.12.1932.5521D2.12.1932.6022A2.22.2802.6022B2.22.2932.6022C2.22.2932.6522D2.22.2932.7023A2.32.3802.7023B2.32.3932.7023C2.32.3932.7523D2.32.3932.802
41、4A2.42.4802.8024B2.42.4932.8024C2.42.4932.8524D2.42.4932.9025A2.52.5802.9025B2.52.5932.9025C2.52.5932.9525D2.52.5933.0026A2.62.6803.0026B2.62.6933.0026C2.62.6933.0526D2.62.6933.1027A2.72.7803.1027B2.72.7933.1027C2.72.7933.1527D2.72.7933.20BRITISH STANDARDBS 4A 116:20126 The British Standards Institu
42、tion 2012Table2BearinglengthL,clampinglengthMandoveralllengthENo.4-40UNCNo.6-32UNCNo.8-32UNCNo.10-32UNFPart No.*Lmin.M +0 0.03E +0.040Part No.*Lmin.M +0 0.03E +0.040Part No.*Lmin.M +0 0.03E +0.040PartNo.*Lmin.M +0 0.03E +0.040inininininininininininin28A2.82.8803.2028B2.82.8933.2028C2.82.8933.2528D2.
43、82.8933.3029A2.92.9803.3029B2.92.9933.3029C2.92.9933.3529D2.92.9933.4030A3.03.0803.4030B3.03.0933.4030C3.03.0933.4530D3.03.0933.5031A3.13.1803.5031B3.13.1933.5031C3.13.1933.5531D3.13.1933.6032A3.23.2803.6032B3.23.2933.6032C3.23.2933.6532D3.23.2933.7033A3.33.3803.7033B3.33.3933.7033C3.33.3933.7533D3.
44、33.3933.8034A3.43.4803.8034B3.43.4933.8034C3.43.4933.8534D3.43.4933.9035A3.53.5803.9035B3.53.5933.9035C3.53.5933.9535D3.53.5934.0036A3.63.6804.0036B3.63.6934.0036C3.63.6934.0536D3.63.6934.1037A3.73.7804.1037B3.73.7934.1037C3.73.7934.1537D3.73.7934.2038A3.83.8804.2038B3.83.8934.2038C3.83.8934.2538D3.
45、83.8934.3014inUNF5/16inUNFPartNo.*Lmin.M +0 0.03E +0.040PartNo.*Lmin.M +0 0.03E +0.040inininininin12E0.050.1510.6512G0.050.1630.701E0.10.2010.701G0.10.2130.752E0.20.3010.802G0.20.3130.853E0.30.4010.903G0.30.4130.954E0.40.5011.004G0.40.5131.055E0.50.6011.105G0.50.6131.156E0.60.7011.206G0.60.7131.257E
46、0.70.8011.307G0.70.8131.358E0.80.9011.408G0.80.9131.459E0.91.0011.509G0.91.0131.5510E1.01.1011.6010G1.01.1131.65BRITISH STANDARD BS 4A 116:2012 The British Standards Institution 2012 7Table2BearinglengthL,clampinglengthMandoveralllengthE14inUNF5/16inUNFPartNo.*Lmin.M +0 0.03E +0.040PartNo.*Lmin.M +0
47、 0.03E +0.040inininininin11E1.11.2011.7011G1.11.2131.7512E1.21.3011.8012G1.21.3131.8513E1.31.4011.9013G1.31.4131.9514E1.41.5012.0014G1.41.5132.0515E1.51.6012.1015G1.51.6132.1516E1.61.7012.2016G1.61.7132.2517E1.71.8012.3017G1.71.8132.3518E1.81.9012.4018G1.81.9132.4519E1.92.0012.5019G1.92.0132.5520E2.
48、02.1012.6020G2.02.1132.6521E2.12.2012.7021G2.12.2132.7522E2.22.3012.8022G2.22.3132.8523E2.32.4012.9023G2.32.4132.9524E2.42.5013.0024G2.42.5133.0525E2.52.6013.1025G2.52.6133.1526E2.62.7013.2026G2.62.7133.2527E2.72.8013.3027G2.72.8133.3528E2.82.9013.4028G2.82.9133.4529E2.93.0013.5029G2.93.0133.5530E3.
49、03.1013.6030G3.03.1133.6531E3.13.2013.7031G3.13.2133.7532E3.23.3013.8032G3.23.3133.8533E3.33.4013.9033G3.33.4133.9534E3.43.5014.0034G3.43.5134.0535E3.53.6014.1035G3.53.6134.15BRITISH STANDARDBS 4A 116:20128 The British Standards Institution 2012Table2BearinglengthL,clampinglengthMandoveralllengthE14inUNF5/16inUNFPartNo.*Lmin.M +0 0.03E +0.040PartNo.*Lmin.M +0 0.03E +0.040inininininin36E3.63.7014.2036G3.63.7134.2537E3.73.8014.3037G3.73.8134.3538E3.83.9014.4038G3.83.9134.45NOTEBoltsbelowthehorizonta
