Общий каталог OSG 2018 - 2019 - страница 661

Thread Limits, Tolerances & Formulas Ground Thread Taps (USCTI Table 331) The following tables and formula are used in determining the limits and tolerances for ground thread taps having a thread lead angle not in excess of 5˚, unless otherwise specified. LEAD TOLERANCE A maximum lead deviation of ±0.0005”, within any two threads not farther apart than 1” is permitted. ANGLE TOLERANCE Threads Per Inch Deviation in Half Angle 4 to 5-1/2 incl. ±20’ 6 to 9 incl. ±25’ 10 to 80 incl. ±30’ FORMULA Max. Major Dia. = Basic + A Max. Pitch Dia. = Min. + D Min. Major Dia. = Basic + B Min. Pitch Dia. = Basic + C In the above formula: A = Constant to add = 0.130P for all Pitches B = Major Diameter Tolerance = 0.087P for 48 Through 80 TPI = 0.076P for 36 Through 47 TPI = 0.065P for 4 Through 35 TPI C = Amount over basic for minimum pitch diameter D = Pitch diameter tolerance Note: When the tap major diameter must be determined from a specified tap pitch diameter, the maximum major diameter equals the minimum specified pitch diameter minus Constant C, plus 0.64952P, plus Constant A. C D ThreadsPer InchA B To 5/8” Incl. Over 5/8” to2 1/2 Incl.Over2 1/2” To Over 1” Over 1 1/2”1”toto 2 1/2”Over 2 1/2”Incl.1 1/2” Incl.Incl. 80 0.0016 0.0011 0.0005 0.0010 0.0015 0.0005 0.0010 0.0010 0.0015 72 0.0018 0.0012 0.0005 0.0010 0.0015 0.0005 0.0010 0.0010 0.0015 64 0.0020 0.0014 0.0005 0.0010 0.0015 0.0005 0.0010 0.0010 0.0015 56 0.0023 0.0016 0.0005 0.0010 0.0015 0.0005 0.0010 0.0010 0.0015 48 0.0027 0.0018 0.0005 0.0010 0.0015 0.0005 0.0010 0.0010 0.0015 44 0.0030 0.0017 0.0005 0.0010 0.0015 0.0005 0.0010 0.0010 0.0015 40 0.0032 0.0019 0.0005 0.0010 0.0015 0.0005 0.0010 0.0010 0.0015 36 0.0036 0.0021 0.0005 0.0010 0.0015 0.0005 0.0010 0.0010 0.0015 32 0.0041 0.0020 0.0010 0.0010 0.0015 0.0005 0.0010 0.0010 0.0015 28 0.0046 0.0023 0.0010 0.0010 0.0015 0.0005 0.0010 0.0010 0.0015 24 0.0054 0.0027 0.0010 0.0010 0.0015 0.0005 0.0010 0.0015 0.0015 20 0.0065 0.0032 0.0010 0.0010 0.0015 0.0005 0.0010 0.0015 0.0015 18 0.0072 0.0036 0.0010 0.0010 0.0015 0.0005 0.0010 0.0015 0.0015 16 0.0081 0.0041 0.0010 0.0010 0.0015 0.0005 0.0010 0.0015 0.0020 14 0.0093 0.0046 0.0010 0.0015 0.0015 0.0005 0.0010 0.0015 0.0020 13 0.0100 0.0050 0.0010 0.0015 0.0015 0.0005 0.0010 0.0015 0.0020 12 0.0108 0.0054 0.0010 0.0015 0.0015 0.0005 0.0010 0.0015 0.0020 11 0.0118 0.0059 0.0010 0.0015 0.0020 0.0005 0.0010 0.0015 0.0020 10 0.0130 0.0065 – 0.0015 0.0020 0.0005 0.0010 0.0015 0.0020 9 0.0144 0.0072 – 0.0015 0.0020 0.0005 0.0010 0.0015 0.0020 8 0.0162 0.0081 – 0.0015 0.0020 0.0005 0.0010 0.0015 0.0020 7 0.0186 0.0093 – 0.0015 0.0020 0.0010 0.0010 0.0020 0.0025 6 0.0217 0.0108 – 0.0015 0.0020 0.0010 0.0010 0.0020 0.0025 5 1/2 0.0236 0.0118 – 0.0015 0.0020 0.0010 0.0015 0.0020 0.0025 5 0.0260 0.0130 – 0.0015 0.0020 0.0010 0.0015 0.0020 0.0025 4 1/2 0.0289 0.0144 – 0.0015 0.0020 0.0010 0.0015 0.0020 0.0025 4 0.0325 0.0162 – 0.0015 0.0020 0.0010 0.0015 0.0020 0.0025 For intermediate pitches, use values for next coarser pitch for C and D, but use formulas for A and B. WWW.OSGTOOL.COM Threading Technical 661