BSP British Straight and Taper Pipe Taps BSP and BSPT

Note: The information contained here is for referance only of common standards and and may not accurately reflect actual product dimensions.

Please check the product details or ask if any dimension is critical

UNIFIED SCREW THREADS FINE SERIES, UNF, BASIC SIZES

BSP British Straight and Taper Pipe Taps
BSP and BSPT

Nominal Size
(inches)
T P I Major Diameter
(inches)
1/8″ 28 0.383
1/4″ 19 0.518
3/8″ 19 0.656
1/2″ 14 0.825
5/8″ 14 0.902
3/4″ 14 1.041
7/8″ 14 1.189
1″ 11 1.309
 1-1/4″
11
 1.650
 1-1/2″
11
1.882
1-3/4″
11
2.116
2″
11
2.347
2-1/4″
11
2.587
2-1/2″
11
2.960
3″
11
3.460

 

Suggested tap drill sizes

British Standard Pipe
Parallel or Taper
BSP or BSPT

Nominal Size
(inches)
T P I Major Diameter
(inches)
Tapping Drill Size Tapping Drill Size
BSP
BSPT
1/16
28
0.304
6.6 mm
 Letter drill G
1/8
28
0.383
8.8 mm  8.4mm
 11/32 inch 21/64″
1/4
19
0.518
11.8 mm 11.2mm
 29/64″
7/16″
3/8
19
0.656
15.25 mm  14.75mm
 19/32″ 37/64″
1/2
14
0.825
19.00mm 18.25mm

3/4″
23/32″
5/8
14
0.902
21 mm
 53/64″
3/4
14
1.041
24.5 mm 23.75mm
 31/32″ 15/16″
7/8
14
1.189
28.25 mm
 1-7/64″
1 inch
11
1.309
30.75 mm 30mm
 1-13/64″ 1-11/64″
 1-1/4″
11
 1.650
 39.50 mm
38.5mm
 1-35/64″ 1-33/64″
 1-1/2″
11
1.882
45.5 mm
44.5mm
 1-25/32″ 1-3/4″
1-3/4″
11
2.116
51.00 mm
 2″
2″
11
2.347
57 mm
56mm
 2-1/4″ 2-3/16″