1、BSI Standards PublicationBS 2A 266 to 2A 271:2016AEROSPACE SERIESBolt, 100 Countersunkhead, Hi-Torque speed driverecess, UNJF thread, split pinhole option, titanium alloy,various finishes,Classification: 80 Tf/in2(1 100 MPa) at TA/+315 CPublishing and copyright informationThe BSI copyright notice di
2、splayed in this document indicates when the documentwas last issued. The British Standards Institution 2016Published by BSI Standards Limited 2016ISBN 978 0 580 91579 6ICS 49.030.20The following BSI references relate to the work on this document:Committee reference ACE/12Draft for comment 15/3032988
3、9 DCPublication historyFirst published January 1977Second (current) edition February 2016Amendments issued since publicationDate Text affectedBS 2A 266 to 2A 271:2016 BRITISH STANDARDContentsForeword ii1 Scope 12 Normative references 13 General requirements 24 BS part number 125 Indentification and
4、marking 12Bibliography 13List of figuresFigure 1 Basic dimensions 2Figure 2 Dimensions: length and optional hole position variables 5Figure 3 Example of part number call up 12Figure4Typical dispersion of the various markings 12List of tablesTable 1 Dimensions (standard shank diameters) 3Table 2 Over
5、size shank diameters 5Table 3 Material and protective finish 5Table 4 Dimensions: lengths and optional hole position variables 6 Summary of pagesThis document comprises a front cover, an inside front cover, pages i to ii,pages 1 to 14, an inside back cover and a back cover.BRITISH STANDARD BS 2A 266
6、 to 2A 271:2016 The British Standards Institution 2016 iForewordPublishing informationThis British Standard is published by BSI Standards Limited, under licence fromThe British Standards Institution, and came into effect on 29 February 2016.It was prepared by Technical Committee ACE/12, Aerospace fa
7、steners andfastening. A list of organizations represented on this committee can be obtainedon request to its secretary.SupersessionThis British Standard supersedes BS A 266 to A 271:1977, which is withdrawn.Information about this documentThis British Standard has been prepared to provide a range of
8、80 Tf/in2(1 100 MPa) to 90 Tf/in2(1 250 MPa) titanium alloy bolts with UNJF profilethreads and close tolerance shanks for aerospace use. The lengths of the boltsare in fractional increments. Dimensions for oversize shank diameters are alsoincluded.When considering the use of cadmium plated titanium
9、bolts, attention is drawnto Def Stan 00-970 Pt.1/12 Section 4 Leaflet 8, which recommends certainlimitations on their use.When bolts are drilled for split pins, they are suitable for use with hexagonalcastle nuts specified in BS A 242 to 245.This is a full revision of the standard, and introduces th
10、e following principalchanges: updating and/or providing additional alternative reference documentnumbers; adding alternative materials to the existing BS TA 28; adding reference document numbers for flushness control and the driverecess; and specifying a temperature rating relating to the strength c
11、lass.Presentational conventionsThe provisions of this standard are presented in roman (i.e. upright) type.Its requirements are expressed in sentences in which the principal auxiliary verbis “shall”.Commentary, explanation and general informative material is presented insmaller italic type, and does
12、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.Compliance with a British Standard cannot confer immunity from legalobligations.BRITISH STA
13、NDARDBS 2A 266 to 2A 271:2016ii The British Standards Institution 20161 ScopeThis British Standard specifies the materials, dimensions, finish and inspectionrequirements for titanium alloy bolts with 100 countersunk heads and UNJFthreads for aerospace use.NOTE The values in Imperial British units ar
14、e to be regarded as the standard.CAUTION. A269 has cadmium as a plating material, which has been restrictedand/or banned for use in many countries owing to environmental and healthconcerns; they should not be used in new product designs. Local officialsshould be consulted about any concerns on using
15、 cadmium-plated parts.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in thisdocument and are indispensable for its application. For dated references, onlythe edition cited applies. For undated references, the latest edition of thereferenced document (i
16、ncluding any amendments) applies.AMS 4967, Titanium alloy, bars, wire, forgings and rings, 6.0Al 4.0V, annealed,heat treatableBS A 346 (ISO 3161), UNJ threads General requirements and limit dimensionsBS A 101, Specification for general requirements for titanium boltsBS A 242 to 245, Specification fo
17、r hexagonal castle nuts (of class 3B UNJ thread)BS A 272, Specification for Hi-torque speed drive recesses Dimensions andgauging for countersunk head fastenersBS A 273, Specification for gauging practice for 100 countersunk head fastenersfor flushness controlBS EN 2133, Cadmium plating of steels wit
18、h specified tensile strength 1450 MPa, copper, copper alloys and nickel alloysBS EN 2808, Anodizing of titanium and titanium alloysBS EN 3813, Titanium alloy TI-P64001 (Ti-6AI-4V) Annealed Bar and wire forforged fasteners De 50 mmBS M 58 (ISO 8080), Specification for anodic coating of titanium and t
19、itaniumalloys by the sulphuric acid processBS TA 28, Specification for forging stock and wire oftitaniumaluminiumvanadium alloy (tensile strength 11001300 MPa) (limitingruling section 20 mm)DTD 942, Anodizing of titanium and titanium alloysSAE AMS 03-19, Electro-deposition of cadmiumSAE AS5272, Lubr
20、icant, solid film, heat cured, corrosion inhibiting procurementspecificationSAE ITC RS678, Fasteners, rolled threads, chamfers, lead threads and runoutsBRITISH STANDARD BS 2A 266 to 2A 271:2016 The British Standards Institution 2016 13 General requirements3.1 The bolts shall be manufactured, inspect
21、ed and tested in accordance withthe requirements of BS A 101.3.2 All bolts shall conform to the dimensions and tolerances given in Table 1,Table 2, Table 4 and Figure 1. Unless otherwise specified, the dimensions arethose before the application of the protective finish.3.3 The principles of flushnes
22、s control and recommended gauging practice shallbe in accordance with BS A 273.3.4 The dimensions of the Hi-torque speed drive recesses shall be as specified inBS A 272.3.5 The material and protective finish requirements shall be as specified inTable 3.Figure 1 Basic dimensionsa) Dimensions of boltb
23、) Enlarged view of headNotes1)The thread lead and runout shall conform to the requirements of SAE ITC RS678.2)See Figure 2 and Table 4 for length dimensions “E”, “L” and “M”.3)The split pin hole option was originally designed to suit the hexagonal castle nuts specified in BS A 242 to 245.4)Holes sha
24、ll have the sharp edges removed.5)For flushness control and gauging of head and drive recess, see BS A 272 and BS A 273.BRITISH STANDARDBS 2A 266 to 2A 271:20162 The British Standards Institution 2016Table1Dimensions(standardshankdiameters)Dimensionsininches1234567891011DiacodeThreadsizeA)ShankdiaAA
25、2PitchThreadlead&runoutTVType:A266A267A268B)Type:A269C)RefUNJFNomMaxMinMaxMinMaxMinMaxMin031032.190.1895.189.1895.1885.063.381.385.376041/428.250.2495.249.2495.2485.071.443.507.497055/1624.3125.312.3115.312.311.083.506.635.625063/824.375.3745.374.3745.3735.083.615.762.752077/1620.4375.437.4365.437.4
26、36.100.631.890.880081/220.500.4995.499.4995.4985.100.7571.0171.007BRITISH STANDARD BS 2A 266 to 2A 271:2016 The British Standards Institution 2016 3(1 of 2)Table1Dimensions(standardshankdiameters)12131415161718192021222324Dia codeBDD)NGauging diameterHeadprotrusionRGChamJholeDriverandrecessnumberPro
27、trusionabovegaugingdiameterPFlushness toleranceAbsolute minimumRefBasicMaxMinMaxMin.020tol03.328.080.3147.029.0263.0027.025.015.130.073+.00550304.449.106.4245.0342.0316.0026.025.015.184.083405.577.133.5389.0395.037.0025.025.015.239.104506.704.160.6532.045.0426.0024.025.015.302.125+.0070607.832.188.7
28、676.0503.0481.0022.025.020.354.146708.959.215.882.0557.0537.002.025.020.416.1678A)Thescrewthreadsshallconformtothebasicthreadform,diameterandrelatedpitchesspecifiedinBSA346forclass3A.B)Beforeapplicationofprotectivefinish.C)Afterapplicationofprotectivefinish.D)Appliestostandardboltshankdiameteronly.H
29、eadheightdimensionsarereducedwithoversizeshanks.Reductionis:.0065in.for.05156in.oversizeboltsand.013in.for.0312in.oversizebolts.BRITISH STANDARDBS 2A 266 to 2A 271:20164 The British Standards Institution 2016(2 of 2)Table 2 Oversize shank diametersDimensions in inches12 345678910DiacodeThreadsizeFir
30、st oversize (code X) Second oversize (code Y)A A A AType:A 266A 267A 268A)Type:A 269B)Type:A 266A 267A 268A)Type:A 269B)UNJF Max Min Max Min Max Min Max Min03 1032 .2026 .2021 .2026 .2016 .2182 .2177 .2182 .217204 1/428 .2651 .2646 .2651 .2641 .2807 .2802 .2807 .279705 5/1624 .3276 .3271 .3276 .3266
31、 .3432 .3427 .3432 .342206 3/824 .3901 .3896 .3901 .3891 .4057 .4052 .4057 .404707 7/1620 .4526 .4521 .4526 .4516 .4682 .4677 .4682 .467208 1/220 .5151 .5146 .5151 .5141 .5307 .5302 .5307 .5297A)Before application of protective finish.B)After application of protective finish.Table 3 Material and pro
32、tective finishBasicBS numberMaterial Mechanical properties Protective finishA266 Titanium alloyTi-6Al-4V toBS TA 28 orBS EN 3813 orAMS 49670.2% proof stress:not less than70 Tf/in2(970 MPa)NoneA267 Anodized in accordance withDTD 942 or BS EN 2808 orBS M 58 (ISO 8080)A268 Tensile strength:not less tha
33、n80 Tf/in2(1100 MPa) andnot more than90 Tf/in2(1250 MPa)Anodized in accordance withDTD 942 or BS EN 2808 orBS M 58 (ISO 8080) + MoS2dry filmlube (heat cured) in accordance withSAE AS5272, Type 1 (Joint ServicesDesignation ZX-34, NATO S-1738)A269A)Cadmium plated in accordance withSAE AMS 03-19 or BS
34、EN 2133 onnickel strikeA270Elongation on 5.65Sonot less than 8%Not yet allocatedA271 Not yet allocatedA)Inactive for new design.Figure 2 Dimensions: length and optional hole position variablesUnallocated diameter/length codes shall not be used.BRITISH STANDARD BS 2A 266 to 2A 271:2016 The British St
35、andards Institution 2016 5Table4Dimensions:lengthsandoptionalholepositionvariablesDimensionsininches1032UNJF1/428UNJF5/1624UNJFDia/length codeL.010E.015M.010Dia/length codeL.010E.015M.010Dia/length codeL.010E.015M.0100302.125.531.3960303.188.594.4590403.188.656.4910503.188.719.5490304.250.656.521040
36、4.250.718.5530504.250.781.6110305.312.718.5830405.312.780.6150505.312.843.6730306.375.781.6460406.375.843.6780506.375.906.7360307.438.844.7090407.438.906.7410507.438.969.7990308.500.906.7710408.500.968.8030508.5001.031.8610309.562.968.8330409.5621.030.8650509.5621.093.9230310.6251.031.8960410.6251.0
37、93.9280510.6251.156.9860311.6881.094.9590411.6881.156.9910511.6881.2191.0490312.7501.1561.0210412.7501.2181.0530512.7501.2811.1110313.8121.2181.0830413.8121.2801.1150513.8121.3431.1730314.8751.2811.1460414.8751.3431.1780514.8751.4061.2360315.9381.3441.2090415.9381.4061.2410515.9381.4691.29903161.000
38、1.4061.27104161.0001.4681.30305161.0001.5311.36103171.0621.4681.33304171.0621.5301.36505171.0621.5931.42303181.1251.5311.39604181.1251.5931.42805181.1251.6561.48603191.1881.5941.45904191.1881.6561.49105191.1881.7191.54903201.2501.6561.52104201.2501.7181.55305201.2501.7811.61103211.3121.7181.58304211
39、.3121.7801.61505211.3121.8431.67303221.3751.7811.64604221.3751.8431.67805221.3751.9061.73603231.4381.8441.70904231.4381.9061.74105231.4381.9691.79903241.5001.9061.77104241.5001.9681.80305241.5002.0311.86103251.5621.9681.83304251.5622.0301.86505251.5622.0931.92303261.6252.0311.89604261.6252.0931.9280
40、5261.6252.1561.98603271.6882.0941.95904271.6882.1561.99105271.6882.2192.04903281.7502.1562.02104281.7502.2182.05305281.7502.2812.11103291.8122.2182.08304291.8122.2802.11505291.8122.3432.17303301.8752.2812.14604301.8752.3432.17805301.8752.4062.236BRITISH STANDARDBS 2A 266 to 2A 271:20166 The British
41、Standards Institution 2016(1 of 6)Table4Dimensions:lengthsandoptionalholepositionvariablesDimensionsininches1032UNJF1/428UNJF5/1624UNJFDia/length codeL.010E.015M.010Dia/length codeL.010E.015M.010Dia/length codeL.010E.015M.01003311.9382.3442.20904311.9382.4062.24105311.9382.4692.29903322.0002.4062.27
42、104322.0002.4682.30305322.0002.5312.36103342.1252.5312.39604342.1252.5932.42805342.1252.6562.48603362.2502.6562.52104362.2502.7182.55305362.2502.7812.61103382.3752.7812.64604382.3752.8432.67805382.3752.9062.73603402.5002.9062.77104402.5002.9682.80305402.5003.0312.86103422.6253.0312.89604422.6253.093
43、2.92805422.6253.1562.98603442.7503.1563.02104442.7503.2183.05305442.7503.2813.11103462.8753.2813.14604462.8753.3433.17805462.8753.4063.23603483.0003.4063.27104483.0003.4683.30305483.0003.5313.36103503.1253.5313.39604503.1253.5933.42805503.2153.6563.48603523.2503.6563.52104523.2503.7183.55305523.2503
44、.7813.61103543.3753.7813.64604543.3753.8433.67805543.3753.9063.73603563.5003.9063.77104563.5003.9683.80305563.5004.0313.86103583.6254.0313.89604583.6254.0933.92805583.6254.1563.98603603.7504.1564.02104603.7504.2184.05305603.7504.2814.11103623.8754.2814.14604623.8754.3434.17805623.8754.4064.23603644.
45、0004.4064.27104644.0004.4684.30305644.0004.5314.36103664.1254.5314.39604664.1254.5934.42805664.1254.6564.48603684.2504.6564.52104684.2504.7184.55305684.2504.7814.61103704.3754.7814.64604704.3754.8434.67805704.3754.9064.73603724.5004.9064.77104724.5004.9684.80305724.5005.0314.86103744.6255.0314.89604
46、744.6255.0934.92805744.6255.1564.98603764.7505.1565.02104764.7505.2185.05305764.7505.2815.11103784.8755.2815.14604784.8755.3435.17805784.8755.4065.23603805.0005.4065.27104805.0005.4685.30305805.0005.5315.36103825.1255.5315.39604825.1255.5935.42805825.1255.6565.48603845.2505.6565.52104845.2505.7185.5
47、5305845.2505.7815.61103865.3755.7815.64604865.3755.8435.67805865.3755.9065.736BRITISH STANDARD BS 2A 266 to 2A 271:2016 The British Standards Institution 2016 7(2 of 6)Table4Dimensions:lengthsandoptionalholepositionvariablesDimensionsininches1032UNJF1/428UNJF5/1624UNJFDia/length codeL.010E.015M.010D
48、ia/length codeL.010E.015M.010Dia/length codeL.010E.015M.01003885.5005.9065.77104885.5005.9685.80305885.5006.0315.86103905.6756.0315.89604905.6256.0935.92805905.6256.1565.98603925.7506.1566.02104925.7506.2186.05305925.7506.2816.11103945.8756.2816.14604945.8756.3436.17805945.8756.4066.23603966.0006.40
49、66.27104966.0006.4686.30305966.0006.5316.361BRITISH STANDARDBS 2A 266 to 2A 271:20168 The British Standards Institution 2016(3 of 6)Table4Dimensions:lengthsandoptionalholepositionvariablesDimensionsininches3/824UNJF7/1620UNJF1/220UNJFDia/length codeL.010E.015M.010Dia/length codeL.010E.015M.010Dia/length codeL.010E.015M.0100604.250.891.6760704.250.906.7410605.312.954.7390705.312.968.8030805.3121.094.9040606.3751.016.8010706.3751.031.86
