20 signifies "20 threads per inch" =.050 pitch ( 1 divided by 20 ) or if you are measuring in metric. standards. - NPT Thread taper angle = 1/16 taper = 1 deg. In Japan this thread is known as (PF) Use prefix G … MM INCH MM INCH MM INCH 0.5 0.45720.0180.61380.024170.93860.03695 0.6 0.45720.0180.46230.018200.85200.03354 0.7 0.45720.0180.31070.012230.76540.03013 0.750.45720.0180.23490.009250.72210.02843 0.8 0.60960.0240.61640.024271.13600.04472 … For example, a 3/8-16 (coarse) thread has a 3/8" nominal major diameter and 16 threads per inch, while a 3/8-24 (fine) thread has the same nominal major diameter and 24 threads per inch. example 1/4-20" taps the. THREAD DATA CHART: British Thread (British Standard Fine) -- Fine Pitch: Nominal Size BSF: Thread Form Type: Major Diameter mm d=D: Pitch mm p: Threads per inch tpi NPT Pipe Thread Depth = Pitch x 0.76. Threads per inch: Pitch in inches: r = Basic Radius = * 137329 p. h = Basic Depth of Thread = *640327 p. p = Pitch = 1/t.p.i. 2. (Threads per Inch) ISO 228, DIN 259, BS2779, JIS B0202. THREAD CHART CONVERSION CHART FOR FOR ALL U.S.60° THREADS 60°METRIC THREADS. TPI = Threads Per Inch. Both the TPI (threads per inch) and OD (outside diameter) of the thread are required for positive identification of thread size because several sizes have the same TPI. threads (inches) Basic minor dia of int. Imperial Thread Chart (Threads per inch) Major Major BSF BSCY Brass BSW UNC UNF BA Size Dia " Dia mm 55° 60° 55° 55° 60° 60° 47.5° 0G 0.0600 1.524 80 1/16 0.0625 1.588 60 10BA 0.0669 1.699 72.6 1G 0.0730 1.854 64 72 9BA 0.0748 1.900 65.1 5/64 0.0781 1.984 56 2G 0.0860 2.184 56 64 8BA 0.0866 2.200 59.1 3/32 0.0938 2.381 48 7BA 0.0984 2.499 52.9 The Coarse Thread Series (UNC/UNRC) is the most common designation for general applications of screws and nuts. The designations of diameter and pitch combinations are covered by the different thread series, and are measured by counting how many threads per inch (TPI) exist in a single diameter. - The angle between the sides of the thread is 60 deg. - Thread Designation: The nominal pipe size, number of threads per inch and the thread series symbol in sequence. it should be 1.27mm . Male threads: Measure the outside diameter of the large portion of the thread at "A"; Find figure nearest this dimension in column 1 or 2 of chart. In the Unified National Series the ½ inch size has 13 threads per inch, but the American Standard was 12 threads per inch. Threads per inch, Pitch in inches, Pitch in mm. Threads per inch: Basic major dia (inches) Basic effective dia (inches) Basic minor dia of ext. Minimum Depth per Pass should not be less than 0.0003. Internal 60° Thread Depth = Pitch x 0.54. ACME Thread Depth = Pitch x 0.5. British Standard 1580 Unified (ISO, inch) screw threads: Parts 1 and 2 (1962); Part 3 (1965). All thread size chart pdf Thread diameter/height series cover markings measured by thread count per inch (TPI) applied to one diameter. British Standard Pipe (BSPP, BSPF) Thread Form. threads (inches) Drill size: 0-80: UNF: 80.0600.0519.0447.0465: 3/64: 1-64: UNC: 64.0730.0629.0538.0561 #54: 2-56: UNC: 56.0860.0744.0641.0667 #50: 2-64: UNF: 64.0860.0759.0668.0691 #50: 4-40: UNC: … The most common designation used for standard industrial bolts and nuts is Coarse Thread … Stub ACME Thread Depth = Pitch x 0.3. 47 min = 0.75 in./ft . Feed Rate = Pitch x Number of Thread Starts.