INCH SIZES - NC - NATIONAL COARSE -------------------------------------------------------- TAP DRILL SIZE SIZE -------------------------------------------------------- #1-64 #53 #2-56 #51 #3-48 5/64 #4-40 #43 #5-40 #39 #6-32 #36 #8-32 #29 #10-24 #25 #12-24 #17 1/4-20 #7 5/16-18 F 3/8-16 5/16 7/16-14 U 1/2-13 27/64 9/16-12 31/64 5/8-11 17/32 3/4-10 21/32 7/8-9 49/64 1"-8 7/8 1-1/8-7 63/64 1-1/4-7 1-7/64 1-1/2-6 1-11/32 1-3/4-5 1-35/64 2"-4-1/2 1-25/32 |
INCH SIZES - NF - NATIONAL FINE -------------------------------------------------------- TAP DRILL SIZE SIZE -------------------------------------------------------- #0-80 3/64 #1-72 #53 #2-64 #50 #3-56 #46 #4-48 #42 #5-44 #37 #6-40 #33 #8-36 #29 #10-32 #21 #12-28 #15 1/4-28 #3 5/16-24 I 3/8-24 Q 7/16-20 W 1/2-20 29/64 9/16-18 33/64 5/8-18 37/64 3/4-16 11/16 7/8-14 13/16 1"-14 15/16 1-1/8-12 1-3/64 1-1/4-12 1-11/64 1-1/2-12 1-27/64 1-3/4-12 1-43/64 2"-12 1-59/64 |
TAPER PIPE SIZES - NPT -------------------------------------------------------- TAP DRILL SIZE SIZE -------------------------------------------------------- 1/8-27 NPT R 1/4-18 NPT 7/16 3/8-18 NPT 37/64 1/2-14 NPT 23/32 3/4-14 NPT 59/64 1"-11-1/2 NPT 1-5/32 1-1/4-11-1/2 NPT 1-1/2 1-1/2-11-1/2 NPT 1-47/64 2"-11-1/2 NPT 2-7/32 2-1/2-8 NPT 2-5/8 3"-8 NPT 3-1/4 3-1/2-8 NPT 3-3/4 4"-8 NPT 4-1/4 |
STRAIGHT PIPE SIZES - NPS -------------------------------------------------------- TAP DRILL SIZE SIZE -------------------------------------------------------- 1/8-27 NPS S 1/4-18 NPS 29/64 3/8-18 NPS 19/32 1/2-14 NPS 47/64 3/4-14 NPS 15/16 1"-11-1/2 NPS 1-3/16 1-1/4-11-1/2 NPS 1-33/64 1-1/2-11-1/2NPS 1-3/4 2"-11-1/2NPS 2-7/32 2-1/2-8 NPS 2-21/32 3"-8 NPS 3-9/32 3-1/2-8 NPS 3-25/32 4"-8 NPS 4-9/32 |