Overall Thread Shank Size of Length of length length dia. square square L ℓ Ds K ℓk NPT (for blind hole) Spiral Fluted Taps Hand Taps for American Taper Pipe Threads Specification (for through hole) Spiral Fluted Taps E Oxide NPT 3/4 ~ Recommended Tapping Speed depending on Materials (for through hole) Spiral Pointed Taps Medium carbon steels 〜5 For icon explanation, refer to P.50 TYPE:1 TYPE:2 Hand Taps Carbide Taps Cemented Segment:1G Size Class Code Chamfer L ℓ Projection Ds K ℓk No. of Type Roll Taps (inch) (inch) (inch) (inch) (inch) (inch) flutes For American Pipe Threads Y83100 NPT 1/16-27 ANSI G 3P 2.125 0.687 0.312 0.312 0.234 0.375 4 1 Y83100BR Y83101 Simple Inspection Tools Pipe Taps 0.437 0.328 1 Y83101BR NPT 1/8-27 ANSI G 3P 2.125 0.75 0.312 0.375 4 Y83102 0.312 0.234 2 Y83102BR Y83103 NPT 1/4-18 ANSI G 3P 2.437 1.062 0.459 0.562 0.421 0.437 4 1 Y83103BR Y83104 NPT 3/8-18 ANSI G 3P 2.562 1.062 0.454 0.7 0.531 0.5 4 1 Y83104BR Y83105 Thread Mills NPT 1/2-14 ANSI G 3P 3.125 1.375 0.579 0.687 0.515 0.625 4 2 Y83105BR Y83106 NPT 3/4-14 ANSI G 3P 3.25 1.375 0.565 0.906 0.679 0.687 4 2 Y83106BR Y83107 Dies NPT 1-11.5 ANSI G 3P 3.75 1.75 0.678 1.125 0.843 0.812 5 2 Y83107BR Y83108 NPT 1 1/4-11.5 ANSI G 3P 4 1.75 0.686 1.312 0.984 0.937 5 2 Y83108BR Y83109 NPT 1 1/2-11.5 ANSI G 3P 4.25 1.75 0.699 1.5 1.125 1 6 2 Center Drills Y83109BR Y83110 NPT 2-11.5 ANSI G 3P 4.5 1.75 0.667 1.875 1.406 1.125 6 2 Y83110BR Centering Tools ANSI Pipe-4 305