ASTM F704-81 (Reapproved 2014)

Designation: F704 − 81 (Reapproved 2014) An American National StandardStandard Practice forSelecting Bolting Lengths for Piping System FlangedJoints1This standard is issued under the fixed designation F704; 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 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. Scope1.1 This practice covers bolt and stud bolt lengths,quantities, and thread series for pipe to pipe and pipe to valveflanged joints (Note 1) in the nominal pipe size ranges of1⁄2- through 48-in. (12.7- through 1219-mm) diameter andpressure range of 125 through 2500 psi (0.8 through 17 236kPa).NOTE 1—This is applicable when flange of valve has the same thicknessas mating flange.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ANSI Standards:2B1.1 Unified Screw ThreadsB16.1 Cast Iron Pipe Flanges and Flanged Fittings (25, 125,250, and 800 lb)B16.5 Steel Pipe Flanges and Flanged Fittings (150, 300,400, 600, 900, 1500, and 2500 lb Including Reference toValves)B16.24 Bronze Flanges and Flanged Fittings (150 and 300lb)B18.2.1 Square and Hex Bolts and ScrewsB18.2.2 Square and Hex Nuts2.2 MSS Standards:3MSS SP-44 Steel Pipe Flanges3. Bolting Criteria3.1 Bolt and stud bolt lengths are computed using thefollowing (see Annex A1):3.1.1 Includes maximum nut thickness in accordance withANSI B18.2.2.3.1.2 Does not include washer thickness.3.1.3 Does not include bolt or stud bolt point height.3.1.4 Includes allowance for up to1⁄8-in. (3.2-mm) thickgaskets, except butterfly valves.3.1.5 Includes1⁄4-in. (6.3-mm) raised face in addition toflange thickness listed in tables for flanges rated at 400 psi (2.8kPa) and above.3.1.6 Includes use of heavy hex nut and bolt design.3.1.7 Includes plus tolerance for flange thickness in accor-dance with ANSI B16.5.3.2 All bolts and stud bolts have threads in accordance withANSI B1.1, Class 2A dimensioning and nuts Class 2B.3.3 The material requirements for bolts, stud bolts, and nutsare obtained from the material specifications of individualsystem diagrams.3.4 Alloy steel bolting 1-in. (25.4-mm) nominal diameterand smaller and all carbon steel bolting has threads of the UNCSeries; alloy steel bolting above 1-in. nominal diameter hasthreads of the 8-UN Series.3.5 For detailed descriptions of flange bolting assemblies,butterfly valve bolting assemblies, and tapped lug-type butter-fly valve bolting assemblies, refer to Figs. 1–7.4. List of Tables4.1 The tables are arranged in the following sequence:150-lb Steel Flanged Joints Table 1300-lb Steel Flanged Joints Table 2400-lb Steel Flanged Joints Table 31This practice is under the jurisdiction of ASTM Committee F25 on Ships andMarine Technology and is the direct responsibility of Subcommittee F25.11 onMachinery and Piping Systems.Current edition approved Nov. 1, 2014. Published November 2014. Originallyapproved in 1981. Last previous edition approved in 2009 as F704 – 81 (2009).DOI: 10.1520/F0704-81R14.2Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http://www.ansi.org.3Available from Manufacturers Standardization Society of the Valve and FittingsIndustry (MSS), 127 Park St., NE, Vienna, VA 22180-4602, http://www.mss-hq.com.Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1600-lb Steel Flanged Joints Table 4900-lb Steel Flanged Joints Table 51500-lb Steel Flanged Joints Table 62500-lb Steel Flanged Joints Table 7150-lb Bronze Flanged Joints Table 8300-lb Bronze Flanged Joints Table 9150-lb Steel Flat Face to 150-lbBronze Flanged JointsTable 10300-lb Steel Flat Face to 300-lbBronze Flanged JointsTable 11125-lb Cast Iron to 150-lb Steel FlatFace Flanged JointsTable 12250-lb Cast Iron to 300-lb Steel FlatFace Flanged JointsTable 13800-lb Cast Iron to 600-lb SteelFlanged JointsTable 14Wafer-Type Butterfly Valve and150-lb Steel FlangesTable 15Wafer-Type Butterfly Valve and150-lb Bronze FlangesTable 16Bolting Lengths for Tapped Lug-Type Butterfly Valve and 150-lbSteel Flanges to ANSI B16.5Table 17Bolting Lengths for Tapped Lug-Type Butterfly Valve and 150 lbBronze Flanges to ANSI B16.24Table 185. Keywords5.1 bolting lengths; cover bolt; flange joint(s); marine tech-nology; ships; stud boltsTABLE 1 Bolting Lengths for 150-lb Steel Flanged Joints to ANSI B16.5 and MSS SP-44 (see Fig. 1 and Fig. 2)NominalPipe Size,in.BoltDiameter,in.AQuantityper JointFlangeThickness,in.ABolt StudBolt ThreadBolt LengthCarbonSteel,in.AStud BoltLengthCar-bon Steel,in.A1⁄21⁄2 47⁄161⁄2-13 UNC-2A 13⁄4 21⁄43⁄41⁄2 41⁄21⁄2-13 UNC-2A 2 21⁄211⁄2 49⁄161⁄2-13 UNC-2A 2 21⁄211⁄41⁄2 45⁄81⁄2-13 UNC-2A 21⁄4 23⁄411⁄21⁄2 411⁄161⁄2-13 UNC-2A 21⁄4 23⁄425⁄8 43⁄45⁄8-11 UNC-2A 23⁄4 31⁄421⁄25⁄8 47⁄85⁄8-11 UNC-2A 3 31⁄235⁄8 415⁄165⁄8-11 UNC-2A 3 31⁄231⁄25⁄8 815⁄165⁄8-11 UNC-2A 3 31⁄245⁄8 815⁄165⁄8-11 UNC-2A 3 31⁄253⁄4 815⁄16 33⁄4-11 UNC-2A 31⁄4 33⁄463⁄4 813⁄4-10 UNC-2A 31⁄4 483⁄41⁄83⁄4-10 UNC-2A 31⁄2 41⁄4107⁄8 12 13⁄167⁄8-9 UNC-2A 33⁄4 41⁄2127⁄8 12 11⁄47⁄8-9 UNC-2A 4 43⁄414 1 12 13⁄8 1-8 UNC-2A 41⁄4 51⁄416 1 16 17⁄16 1-8 UNC-2A 41⁄2 51⁄418 11⁄8 16 19⁄16 11⁄8-7 UNC-2A 53⁄420 11⁄8 20 111⁄16 11⁄8-7 UNC-2A 51⁄4 61⁄424 11⁄4 20 17⁄8 11⁄4-7 UNC-2A 53⁄4 63⁄426 11⁄4 24 211⁄16 111⁄16-7 UNC-2A 71⁄4 81⁄228 11⁄4 28 213⁄16 11⁄4-7 UNC-2A 71⁄2 83⁄430 11⁄4 28 215⁄16 11⁄4-7 UNC-2A 73⁄4 932 11⁄2 28 33⁄16 11⁄2-6 UNC-2A 83⁄4 1034 11⁄2 32 31⁄4 11⁄2-6 UNC-2A 83⁄4 1036 11⁄2 32 39⁄16 11⁄2-6 UNC-2A 91⁄2 103⁄438 11⁄2 32 37⁄16 11⁄2-6 UNC-2A 91⁄4 101⁄240 11⁄2 36 39⁄16 11⁄2-6 UNC-2A 91⁄2 103⁄442 11⁄2 36 313⁄16 11⁄2-6 UNC-2A 10 111⁄444 11⁄2 40 4 11⁄2-6 UNC-2A 101⁄4 111⁄246 11⁄2 40 41⁄16 11⁄2-6 UNC-2A 101⁄2 113⁄448 11⁄2 44 41⁄4 11⁄2-6 UNC-2A 103⁄4 121⁄4A1 in. = 25.4 mm.F704 − 81 (2014)2TABLE 2 Bolting Lengths for 300-lb Steel Flanged Joints to ANSI B16.5 (see Fig. 1 and Fig. 2)NominalPipe Size,in.BoltDiameter,in.AQuantityper JointFlangeThickness,in.ABolt StudBolt ThreadBolt LengthCarbonSteel,in.AStud BoltLengthCar-bon Steel,in.A1⁄21⁄2 49⁄161⁄2-13 UNC-2A 2 21⁄23⁄45⁄8 45⁄85⁄8-11 UNC-2A 21⁄4 315⁄8 411⁄165⁄8-11 UNC-2A 21⁄2 311⁄45⁄8 43⁄45⁄8-11 UNC-2A 21⁄2 31⁄411⁄23⁄4 413⁄163⁄4-10 UNC-2A 3 31⁄225⁄8 87⁄85⁄8-11 UNC-2A 3 31⁄221⁄23⁄4 813⁄4-10 UNC-2A 31⁄4 433⁄41⁄83⁄4-10 UNC-2A 31⁄2 41⁄431⁄23⁄43⁄163⁄4-10 UNC-2A 33⁄4 41⁄443⁄4 811⁄43⁄4-10 UNC-2A 33⁄4 41⁄253⁄43⁄83⁄4-10 UNC-2A 4 43⁄463⁄4 12 17⁄163⁄4-10 UNC-2A 41⁄4 43⁄487⁄8 12 15⁄87⁄8-8 UNC-2A 43⁄4 51⁄210 1 16 17⁄8 1-8 UNC-2A 51⁄4 61⁄412 11⁄8 16 2 11⁄8-7 UNC-2A 53⁄4 63⁄414 11⁄8 20 21⁄8 11⁄8-7 UNC-2A 6 716 11⁄4 20 21⁄4 11⁄4-7 UNC-2A 61⁄4 718 11⁄4 24 23⁄8 11⁄4-7 UNC-2A 61⁄2 73⁄420 11⁄4 24 21⁄2 11⁄4-7 UNC-2A 7 824 11⁄2 24 23⁄4 11⁄2-6 UNC-2A 73⁄4 9A1 in. = 25.4 mm.TABLE 3 Bolting Lengths for 400-lb Steel Flanged Joints to ANSI B16.5 (see Fig. 3 and Fig. 4)NominalPipe Size,in.BoltDiameter,in.AQuantityper JointFlangeThickness,in.ABolt StudBolt ThreadBolt LengthAlloySteel, in.AStud BoltLength Al-loySteel, in.A1⁄2BBB B BB3⁄4111⁄4BBB B BB11⁄2221⁄2BBB B BB331⁄247⁄8 813⁄87⁄8-9 UNC-2A not used 51⁄257⁄81⁄27⁄8-9 UNC-2A not used 53⁄467⁄8 12 15⁄87⁄8-9 UNC-2A not used 681127⁄8 1-8 UNC-2A not used 63⁄410 11⁄8 16 21⁄8 11⁄8-8 UN-2A not used 71⁄212 11⁄4 16 21⁄4 11⁄4-8 UN-2A not used 814 11⁄4 20 23⁄8 11⁄4-8 UN-2A not used 81⁄416 13⁄8 20 21⁄2 13⁄8-8 UN-2A not used 83⁄418 13⁄8 24 25⁄8 13⁄8-8 UN-2A not used 920 11⁄2 24 23⁄4 11⁄2-8 UN-2A not used 91⁄224 13⁄4 24 3 13⁄4-8 UN-2A not used 101⁄2A1 in. = 25.4 mm.BFor dimensions of these pipe sizes, refer to Table 4.F704 − 81 (2014)3TABLE 4 Bolting Lengths for 600-lb Steel Flanged Joints to ANSI B16.5 (see Fig. 3 and Fig. 4)NominalPipe Size,in.BoltDiameter,in.AQuantityper JointFlangeThickness,in.ABolt StudBolt ThreadBolt LengthAlloySteel, in.AStud BoltLength Al-loySteel, in.A1⁄21⁄2 49⁄161⁄2-13 UNC-2A not used 33⁄45⁄8 45⁄85⁄8-11 UNC-2A not used 31⁄215⁄8 411⁄165⁄8-11 UNC-2A not used 31⁄211⁄45⁄8 413⁄165⁄8-11 UNC-2A not used 33⁄411⁄23⁄4 47⁄83⁄4-10 UNC-2A not used 41⁄425⁄8 815⁄8-11 UNC-2A not used 41⁄421⁄23⁄41⁄83⁄4-10 UNC-2A not used 43⁄433⁄41⁄43⁄4-10 UNC-2A not used 531⁄27⁄8 813⁄87⁄8-9 UNC-2A not used 51⁄247⁄81⁄27⁄8-9 UNC-2A not used 53⁄451 83⁄4 1-8 UNC-2A not used 61⁄261127⁄8 1-8 UNC-2A not used 63⁄4811⁄8 12 23⁄16 11⁄8-8 UN-2A not used 71⁄210 11⁄4 16 21⁄2 11⁄4-8 UN-2A not used 81⁄212 11⁄4 20 25⁄8 11⁄4-8 UN-2A not used 83⁄414 13⁄8 20 23⁄4 13⁄8-8 UN-2A not used 91⁄416 11⁄2 20 3 11⁄2-8 UN-2A not used 1018 15⁄8 20 31⁄4 15⁄8-8 UN-2A not used 103⁄420 15⁄8 24 31⁄2 15⁄8-8 UN-2A not used 111⁄424 17⁄8 24 4 17⁄8-8 UN-2A not used 13A1 in. = 25.4 mm.TABLE 5 Bolting Lengths for 900-lb Steel Flanged Joints to ANSI B16.5 (see Fig. 3 and Fig. 4)NominalPipe Size,in.BoltDiameter,in.AQuantityper JointFlangeThickness,in.ABolt StudBolt ThreadBolt LengthAlloySteel, in.AStud BoltLength Al-loySteel, in.A1⁄2BBB B BB3⁄4111⁄4BBB B BB11⁄2221⁄2BBB B BB37⁄8 811⁄27⁄8-9 UNC-2A not used 53⁄4411⁄83⁄4 11⁄8-8 UN-2A not used 63⁄4511⁄4 821⁄4-8 UN-2A not used 71⁄2611⁄8 12 23⁄16 11⁄8-8 UN-2A not used 71⁄2813⁄8 12 21⁄2 13⁄8-8 UN-2A not used 83⁄410 13⁄8 16 23⁄4 13⁄8-8 UN-2A not used 91⁄412 13⁄8 20 31⁄8 13⁄8-8 UN-2A not used 1014 11⁄2 20 33⁄8 11⁄2-8 UN-2A not used 103⁄416 15⁄8 20 31⁄2 15⁄8-8 UN-2A not used 111⁄418 17⁄8 20 4 17⁄8-8 UN-2A not used 123⁄420 2 20 41⁄4 2-8 UN-2A not used 133⁄424 21⁄2 20 51⁄2 21⁄2-8 UN-2A not used 171⁄4A1 in. = 25.4 mm.BFor dimensions of these pipe sizes, refer to Table 6.F704 − 81 (2014)4TABLE 6 Bolting Lengths for 1500-lb Steel Flanged Joints to ANSI B16.5 (see Fig. 3 and Fig. 4)NominalPipe Size,in.BoltDiameter,in.AQuantityper JointFlangeThickness,in.ABolt StudBolt ThreadBolt LengthAlloySteel, in.AStud BoltLength Al-loySteel, in.A1⁄23⁄4 47⁄83⁄4-10 UNC-2A not used 41⁄43⁄43⁄4 413⁄4-10 UNC-2A not used 41⁄217⁄81⁄87⁄8-9 UNC-2A not used 511⁄47⁄81⁄87⁄8-9 UNC-2A not used 511⁄2 141⁄4 1-8 UNC-2A not used 51⁄227⁄8 811⁄27⁄8-9 UNC-2A not used 53⁄421⁄2 185⁄8 1-8 UNC-2A not used 61⁄4311⁄87⁄8 11⁄8-8 UN-2A not used 7411⁄4 821⁄8 11⁄4-8 UN-2A not used 73⁄4511⁄27⁄8 11⁄2-8 UN-2A not used 93⁄4613⁄8 12 31⁄4 13⁄8-8 UN-2A not used 101⁄4815⁄8 12 35⁄8 15⁄8-8 UN-2A not used 111⁄210 17⁄8 12 41⁄4 17⁄8-8 UN-2A not used 131⁄412 2 16 47⁄8 2-8 UN-2A not used 143⁄414 21⁄4 16 51⁄4 21⁄4-8 UN-2A not used 1616 21⁄2 16 53⁄4 21⁄2-8 UN-2A not used 171⁄218 23⁄4 16 63⁄8 23⁄4-8 UN-2A not used 191⁄220 3 16 7 3-8 UN-2A not used 211⁄424 31⁄2 16 8 31⁄2-8 UN-2A not used 241⁄4A1 in. = 25.4 mm.TABLE 7 Bolting Lengths for 2500-lb Steel Flanged Joints to ANSI B16.5 (see Fig. 3 and Fig. 4)NominalPipe Size,in.BoltDiameter,in.AQuantityper JointFlangeThickness,in.ABolt StudBolt ThreadBolt LengthAlloySteel, in.AStud BoltLength Al-loySteel, in.A1⁄23⁄4 413⁄163⁄4-10 UNC-2A not used 43⁄43⁄43⁄41⁄43⁄4-10 UNC-2A not used 517⁄83⁄87⁄8-9 UNC-2A not used 51⁄211⁄4 141⁄2 1-8 UNC-2A not used 611⁄2 11⁄8 413⁄4 11⁄8-8 UN-2A not used 63⁄42 1 8 2 1-8 UNC-2A not used 721⁄2 11⁄8 821⁄4 11⁄8-8 UN-2A not used 73⁄4311⁄45⁄8 11⁄4-8 UN-2A not used 83⁄4411⁄2 831⁄2-8 UN-2A not used 10513⁄45⁄8 13⁄4-8 UN-2A not used 113⁄462 841⁄4 2-8 UN-2A not used 131⁄28 2 12 5 2-8 UN-2A not used 1510 21⁄2 12 61⁄2 21⁄2-8 UN-2A not used 191⁄412 23⁄4 12 71⁄4 23⁄4-8 UN-2A not used 211⁄4A1 in. = 25.4 mm.F704 − 81 (2014)5TABLE 8 Bolting Lengths for 150-lb Bronze Flanged Joints to ANSI B16.24 (see Fig. 1 and Fig. 2)NominalPipe Size,in.BoltDiameter,in.AQuantityper JointFlangeThickness,in.ABolt StudBolt ThreadBolt LengthCarbonSteel,in.AStud BoltLengthCar-bon Steel,in.A1⁄21⁄2 45⁄161⁄2-13 UNC-2A 11⁄2 23⁄41⁄2 411⁄321⁄2-13 UNC-2A 13⁄4 21⁄411⁄2 43⁄81⁄2-13 UNC-2A 13⁄4 21⁄411⁄41⁄2 413⁄321⁄2-13 UNC-2A 13⁄4 21⁄411⁄21⁄2 47⁄161⁄2-13 UNC-2A 13⁄4 21⁄425⁄8 41⁄25⁄8-11 UNC-2A 2 23⁄421⁄25⁄8 49⁄165⁄8-11 UNC-2A 21⁄4 23⁄435⁄8 45⁄85⁄8-11 UNC-2A 21⁄4 331⁄25⁄8 811⁄165⁄8-11 UNC-2A 21⁄2 345⁄8 811⁄165⁄8-11 UNC-2A 21⁄2 353⁄4 83⁄43⁄4-10 UNC-2A 23⁄4 31⁄263⁄4 813⁄163⁄4-10 UNC-2A 3 31⁄283⁄4 815⁄163⁄4-10 UNC-2A 31⁄4 33⁄4107⁄8 12 17⁄8-9 UNC-2A 31⁄2 41⁄4127⁄8 12 11⁄67⁄8-9 UNC-2A 31⁄2 41⁄4A1 in. = 25.4 mm.TABLE 9 Bolting Lengths for 300-lb Bronze Flanged Joints to ANSI B16.24 (see Fig. 1 and Fig. 2)NominalPipeSize, in.BoltDiameter,in.AQuantityper JointFlangeThickness,in.ABolt StudBolt ThreadBolt LengthCarbonSteel,in.AStud BoltLengthCarbonSteel, in.A1⁄21⁄2 41⁄21⁄2-13 UNC-2A 2 21⁄23⁄45⁄8 417⁄325⁄8-11 UNC-2A 21⁄4 23⁄415⁄8 419⁄325⁄8-11 UNC-2A 21⁄4 311⁄45⁄8 45⁄85⁄8-11 UNC-2A 21⁄4 311⁄23⁄4 411⁄163⁄4-10 UNC-2A 21⁄2 31⁄425⁄8 83⁄45⁄8-11 UNC-2A 21⁄2 31⁄421⁄23⁄4 813⁄163⁄4-10 UNC-2A 3 31⁄233⁄4 829⁄323⁄4-10 UNC-2A 3 33⁄431⁄23⁄4 831⁄323⁄4-10 UNC-2A 31⁄4 443⁄4 811⁄163⁄4-10 UNC-2A 31⁄4 453⁄41⁄83⁄4-10 UNC-2A 31⁄2 41⁄463⁄4 12 13⁄163⁄4-10 UNC-2A 31⁄2 41⁄487⁄8 12 13⁄87⁄8-9 UNC-2A 41⁄4 5A1 in. = 25.4 mm.F704 − 81 (2014)6TABLE 10 Bolting Lengths for 150-lb Steel Flat Face to Bronze Flanged Joints to ANSI B16.5 and B16.24(see Fig. 1 and Fig. 2)NominalPipe Size,in.BoltDiameter,in.AQuantityper JointFlange Thickness, in.ABolt StudBolt ThreadBolt LengthCarbonSteel, in.AStud BoltLengthCar-bon Steel,in.ASteel Bronze1⁄21⁄2 47⁄165⁄161⁄2-13 UNC-2A 13⁄4 21⁄43⁄41⁄2 41⁄211⁄321⁄2-13 UNC-2A 13⁄4 21⁄411⁄2 49⁄163⁄81⁄2-13 UNC-2A 13⁄4 21⁄411⁄41⁄2 45⁄813⁄321⁄2-13 UNC-2A 2 21⁄211⁄21⁄2 411⁄167⁄161⁄2-13 UNC-2A 2 21⁄225⁄8 43⁄41⁄25⁄8-11 UNC-2A 21⁄4 321⁄25⁄8 47⁄89⁄165⁄8-11 UNC-2A 21⁄2 31⁄435⁄8 415⁄165⁄85⁄8-11 UNC-2A 23⁄4 31⁄431⁄25⁄8 815⁄1611⁄165⁄8-11 UNC-2A 23⁄4 31⁄445⁄8 815⁄1611⁄165⁄8-11 UNC-2A 23⁄4 31⁄453⁄4 815⁄163⁄43⁄4-10 UNC-2A 3 33⁄463⁄4 8113⁄163⁄4-10 UNC-2A 3 33⁄483⁄41⁄815⁄163⁄4-10 UNC-2A 31⁄4 4107⁄8 12 13⁄16 17⁄8-9 UNC-2A 31⁄2 41⁄2127⁄8 12 11⁄4 11⁄167⁄8-9 UNC-2A 33⁄4 41⁄2A1 in. = 25.4 mm.TABLE 11 Bolting Lengths for 300-lb Steel Flat Face to Bronze Flanged Joints to ANSI B16.5 and B16.24(see Fig. 1 and Fig. 2)NominalPipe Size,in.BoltDiameter,in.AQuantityper JointFlange Thickness, in.ABolt StudBolt ThreadBolt LengthCarbonSteel, in.AStud BoltLengthCar-bon Steel,in.ASteel Bronze1⁄21⁄2 49⁄161⁄21⁄2-13 UNC-2A 2 21⁄23⁄45⁄8 45⁄817⁄325⁄8-11 UNC-2A 21⁄4 23⁄415⁄8 411⁄1619⁄325⁄8-11 UNC-2A 21⁄4 311⁄45⁄8 43⁄45⁄85⁄8-11 UNC-2A 21⁄2 311⁄23⁄4 413⁄1611⁄163⁄4-10 UNC-2A 23⁄4 31⁄225⁄8 87⁄83⁄45⁄8-11 UNC-2A 23⁄4 31⁄421⁄23⁄4 8113⁄163⁄4-10 UNC-2A 3 33⁄433⁄41⁄829⁄323⁄4-10 UNC-2A 31⁄4 431⁄23⁄4 813⁄1631⁄323⁄4-10 UNC-2A 31⁄2 443⁄4 811⁄4 11⁄163⁄4-10 UNC-2A 31⁄2 41⁄453⁄43⁄8 11⁄83⁄4-10 UNC-2A 33⁄4 41⁄263⁄4 12 17⁄1613⁄163⁄4-10 UNC-2A 33⁄4 41⁄287⁄8 12 15⁄8 13⁄87⁄8-9 UNC-2A 41⁄2 51⁄4A1 in. = 25.4 mm.F704 − 81 (2014)7TABLE 12 Bolting Lengths