Page 145 - Content.pmd

COMMERCIAL DRILL SIZES ISO INCH (UNIFIED) THREAD

NC National Coarse NF National Fine

Tap size Tharads Tap dirll size Tap size Therads Tap drill size
per inch per inch

5 40 38 5 44 37

6 32 36 6 40 33
8 32 29 8 36 29
10 24 25 10 32 21

12 24 16 12 28 14
1/4 " 20 7 1/4 " 28 3
5/16 " 18 F 5/16 " 24 1

3/8 " 16 5/16 " 3/8 " 24 0
7/16 " 14 U 7/16 " 20 25/64 "

1/2 " 13 27/64 " 1/2 " 20 29/64 "
9/16 " 12 31/64 " 9/16 " 18 33/64 "
5/8 " 11 17/32 " 5/8 " 18 37/64 "

3/4 " 10 21/32 " 3/4 " 16 11/16 "
7/8 " 9 49/64 " 7/8 " 14 13/16 "

1" 8 7/8 " 1 " 14 15/16 "
1 1/8 " 7 63/64 " 1 1/8 " 12 1 3/6 "
1 1/4 " 7 17/64 " 1 1/4 " 12 1 11/6 "

1 3/8 " 6 17/32 " 1 3/8 " 12 1 19/64
"

1 3/4 " 5 1 9/16 "
2 " 4 1/2 1 25/32 "

NPT National pipe thread
1/8 " 27 11/32 " 1 " 11 1/2 1 5/32 "

1/4 ' 18 7/16 " 1 1/4 " 11 1/4 1 1/2 "

3/8 " 18 19/32 " 1 1/2 " 11 1/2 1 23/32 "

1/2 " 14 23/32 " 2 " 11 1/2 2 23/16 "

3/4 " 14 15/16 " 2 1/2 " 8 2 5/8 "

£_õ & Gm: @©hPo (NSQF - Revised 2022) R.T. for Ex.1.2.39 - 41
124