Page 722 - Yamawa_European_Catalogue_YEU21

24. Drill size and recommended hole size for cutting taps

Intro

American Pipe Threads (NPSC) Unit: mm American Pipe Threads (NPSM) Unit: mm
SP
Minor Diameter Minor Diameter
Size Drill Recommended Size Drill Recommended
Size Hole Size Size Hole Size
Max. Min. Max. Min.
NPSC 1/16 - 27 6.604 6.300 6.50 6.53 NPSM 1/16 - 27 6.898 6.747 6.80 6.86
SL NPSC 1/8 - 27 8.940 8.636 8.80 8.86 NPSM 1/8 - 27 9.246 9.094 9.20 9.21
NPSC 1/4 - 18 11.633 11.227 11.50 11.53 NPSM 1/4 - 18 12.217 11.888 12.10 12.13
NPSC 3/8 - 18 15.087 14.656 14.90 14.98 NPSM 3/8 - 18 15.554 15.317 15.50 15.49
NPSC 1/2 - 14 18.643 18.161 18.50 18.52 NPSM 1/2 - 14 19.278 18.974 19.20 19.20
PO NPSC 3/4 - 14 24.003 23.495 23.75 23.88 NPSM 3/4 - 14 24.638 24.334 24.50 24.60
NPSC 1 - 11.5 30.073 29.490 29.80 29.93 NPSM 1 - 11.5 30.759 30.506 30.60 30.70
NPSC 1 1/4 - 11.5 38.836 38.253 38.50 38.69 NPSM 1 1/4 - 11.5 39.497 39.269 39.40 39.40
NPSC 1 1/2 - 11.5 44.907 44.323 44.75 44.76 NPSM 1 1/2 - 11.5 45.567 45.339 45.50 45.50
NPSC 2 - 11.5 56.946 56.363 56.75 56.80 NPSM 2 - 11.5 57.607 57.379 57.50 57.60
ST

Dryseal American Pipe Threads (NPSF) Unit: mm
ROLL
Minor Diameter
Size Drill Recommended
Size Hole Size
Max. Min.
NPSF 1/16 - 27 6.482 6.305 6.40 6.44
CARBIDE
NPSF 1/8 - 27 8.740 8.652 8.70 8.72
NPSF 1/4 - 18 11.363 11.232 11.30 11.33
NPSF 3/8 - 18 14.803 14.672 14.75 14.77
NPSF 1/2 - 14 18.288 18.118 18.25 18.20
LONG NPSF 3/4 - 14 23.634 23.465 23.50 23.50
NPSF 1 - 11.5 29.669 29.464 29.50 29.60
NPSF 1 1/4 - 11.5 38.514 38.220 38.30 38.40
NPSF 1 1/2 - 11.5 44.584 44.290 44.50 44.50
HAND NPSF 2 - 11.5 56.621 56.328 56.50 56.50
TAPS

EG (STI)

SPECIAL
THREADS,
GAUGES

THREAD
MILLS

DIES

CENTER
DRILLS

Technical
info

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