British
Pipe Thread ( Whitworth Form) -- Taper (BSPT)
Thread
Designation
BSPT
Nominal
Size
BSPT
Thread
Form
Type
Major
Diameter
mm
d=D
Pitch
mm
p
Threads
per
inch
tpi
Pitch
Diameter
mm
d2=D2
Minor
Diameter
Male Thd.
d3
Thread
Height
H1
Rounding
r
Tap
Drill
Diameter
mm
R 1/16
1/16"
BSPT
7.723
0.907
28
7.142
6.561
0.581
0.125
6.4
R 1/8
1/8"
BSPT
9.728
0.907
28
9.147
8.566
0.581
0.125
8.4
R 1/4
1/4"
BSPT
13.157
1.337
19
12.301
11.445
0.856
0.184
11.2
R 3/8
3/8"
BSPT
16.662
1.337
19
15.806
14.950
0.856
0.184
14.75
R 1/2
1/2"
BSPT
20.955
1.814
14
19.793
18.631
1.162
0.249
18.25
R 3/4
3/4"
BSPT
26.441
1.814
14
25.279
24.117
1.162
0.249
23.75
R 1
1"
BSPT
33.249
2.309
11
31.77
30.291
1.479
0.317
30
R 1 1/4
1 1/4"
BSPT
41.910
2.309
11
40.431
38.952
1.479
0.317
38.5
R 1 1/2
1 1/2"
BSPT
47.803
2.309
11
46.324
44.845
1.479
0.317
44.5
R 2
2"
BSPT
59.614
2.309
11
58.135
56.656
1.479
0.317
56
R 2 1/2
2 1/2"
BSPT
75.184
2.309
11
73.705
72.226
1.479
0.317
71
R 3
3"
BSPT
87.884
2.309
11
86.405
84.926
1.479
0.317
85.5
R 4
4"
BSPT
113.030
2.309
11
111.551
110.072
1.479
0.317
110.5
R 5
5"
BSPT
138.430
2.309
11
136.951
135.472
1.479
0.317
136
R 6
6"
BSPT
163.830
2.309
11
162.351
160.872
1.479
0.317
161.5
Disclaimer
This data is provided for general information only. The intention is to provide accurate information; regardless; errors may exist in the supplied information. If accuracy is critical, base your final decisions on the data provided in the root document: ISO 7; which is a copyrighted document. To purchase a copy visit an Authorized Reseller.
Comments:
Original Posting: 2/28/2008
Last Revision: 2/13/2013
Error corrections in, or comments about, the above data can be sent to: office@gagecrib.com
Gage Crib Worldwide, Inc.
6701 Old 28th St SE, Suite B
Grand Rapids, MI 49546-6937
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