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British Standard Pipe Threads (BSPP, BSPF) PDF Download

Dash Size Nominal Thread Size - t.p.i. Basic depth of thread (h) (in.) Basic Major Dia. (in.) Basic effective Dia. (in.) Basic Minor Dia. (in.) Recommended tap drill size
size Rp (mm) Size G (mm)
-1 1/16-28 .0229 .304 .2812 .2583 6.60 6.80
-2 1/8-28 .0229 .383 .3601 .3372 8.60 8.80
-4 1/4-19 .0337 .518 .4843 .4506 11.50 11.80
-6 3/8-19 .0337 .656 .6223 .5886 15.00 15.25
-8 1/2-14 .0457 .825 .7793 .7336 18.50 19.00
-10 5/8-14 .0457 .902 .8563 .8106 - 21.00
-12 3/4-14 .0457 1.041 .9953 .9496 24.00 24.50
-14 7/8-14 .0457 1.189 1.1433 1.0976 - 23.25
-16 1-11 .0582 1.309 1.2508 1.1926 30.25 30.75
-20 1 1/4-11 .0582 1.650 1.5918 1.5336 39.00 39.50
-24 1 1/2-11 .0582 1.882 1.8238 1.7656 45.00 45.00
-28 1 3/4-11 .0582 2.116 2.0578 1.9996 - 51.00
-32 2-11 .0582 2.347 2.2888 2.2306 56.50 57.00
-36 2 1/4-11 .0582 2.587 2.5288 2.4706 No Sizes of B.S. (British Standard) drills are recommended in B.S. 1157:1975 for this range
-40 2 1/2-11 .0582 2.960 2.9018 2.8436
-44 2 3/4-11 .0582 3.210 3.1518 3.0936
-48 3-11 .0582 3.460 3.4018 3.3436
-52 3 1/4-11 .0582 3.700 3.6418 3.5836
-56 3 1/2-11 .0582 3.950 3.8918 3.8336
-60 3 3/4-11 .0582 4.200 4.1418 4.0836
-64 4-11 .0582 4.450 4.3918 4.3336
British Standard Pipe(BSPP, BSPF)
Thread Form

r = Basic Radius = * 137329 p

h = Basic Depth of Thread = *640327 p

p = Pitch = 1/t.p.i. (Threads per Inch)

ISO 228, DIN 259, BS2779, JIS B0202

In Japan this thread is known as (PF)

Use prefix G for parallel thread. Example: G1/2

Metric Threads PDF Download

Tube Size (mm) AL Series LL Series L Series S Series A Series AG Series DIN 7631 60 degree cone
4 M 8 X 0.75 M 8 X 1.0 ---- ---- M 10 X 1.5 ---- M 12 X 1.5
6 M 10 X 1.0 M 10 X 1.0 M 12 X 1.5 M 14 X 1.5 M 12 X 1.5 ---- M 14 X 1.5
8 M 12 X 1.0 M 12 X 1.0 M 14 X 1.5 M 16 X 1.5 M 14 X 1.5 ---- M 16 X 1.5
10 M 14 X 1.0 M 14 X 1.0 M 16 X 1.5 M 18 X 1.5 M 16 X 1.5 ---- M 18 X 1.5
12 M 16 X 1.0 M 16 X 1.0 M 18 X 1.5 M 20 X 1.5 M 18 X 1.5 ---- M 22 X 1.5
13 ---- ---- ---- ---- ---- M 20 X 1.5 ----
14 M 18 X 1.0 ---- ---- M 22 X 1.5 M 20 X 1.5 ---- ----
15 M 20 X 1.0 ---- M 22 X 1.5 ---- M 22 X 1.5 ---- ----
16 M 22 X 1.0 ---- ---- M 24 X 1.5 M 24 X 1.5 ---- M 26 X 1.5
17 ---- ---- ---- ---- ---- M 24 X 1.5 ----
18 M 24 X 1.0 ---- M 26 X 1.5 ---- M 27 X 1.5 ---- ----
20 M 25 X 1.0 ---- ---- M 30 X 2.0 M 27 X 1.5 ---- M 30 X 1.5
21 ---- ---- ---- ---- ---- M 30 X 1.5 ----
22 ---- ---- M 30 X 2.0 ---- M 30 X 1.5 ---- ----
25 ---- ---- ---- M 36 X 2.0 M 33 X 1.5 ---- M 38 X 1.5
27 ---- ---- ---- ---- ---- M 36 X 1.5 ----
28 ---- ---- M 36 X 2.0 ---- M 36 X 1.5 ---- ----
30 ---- ---- ---- M 42 X 2.0 M 39 X 1.5 ---- ----
32 ---- ---- ---- ---- ---- ---- M 45 X 1.5
33 ---- ---- ---- ---- ---- M 45 X 1.5 ----
35 ---- ---- M 45 X 2.0 ---- M 45 X 1.5 ---- ----
38 ---- ---- ---- M 52 X 2.0 M 48 X 1.5 ---- ----
40 ---- ---- ---- ---- M 52 X 1.5 ---- M 52 X 1.5
42 ---- ---- M 52 X 2.0 ---- ---- M 52 X 1.5 ----
45 ---- ---- ---- ---- M 54 X 2.0 ---- ----
48 ---- ---- ---- ---- M 58 X 2.0 ---- ----
49 ---- ---- ---- ---- ---- M 58 X 2.0 ----

American National Pipe Taper (NPT) PDF Download

Dash Size Nominal Thread Size - t.p.i. Basic depth of thread (h) (in.) Outside dia. of pipe (in.) Effective diameter at small end of external thread (in.) Basic Minor Dia. (in.) Recommended tap drill size (mm)
-1 1/16 - 27 .0296 .3125 .2712 .2812 6.30
-2 1/8 - 27 .0296 .405 .3635 .3736 8.70
-4 1/4 - 18 .0444 .540 .4774 .4916 11.10
-6 3/8 - 18 .0444 .675 .6120 .6270 14.50
-8 1/2 - 14 .0571 .840 .7584 .7784 18.00
-12 3/4 - 14 .0571 1.050 .9677 .9889 23.25
-16 1 - 11-1/2 .0696 1.315 1.2136 1.2386 29.00
-20 1 1/4 - 11-1/2 .0696 1.660 1.5571 1.5834 38.00
-24 1 1/2 - 11-1/2 .0696 1.900 1.7961 1.8223 44.00
-32 2 - 11-1/2 .0696 2.375 2.2690 2.2963 56.00
-40 2 1/2 - 8 .1000 2.875 2.7195 2.7622 67.00
American National Pipe Taper (NPT)
Thread Form

h = Basic Depth of Thread = *8 p

p = Pitch = 1/t.p.i. (Threads per Inch)

SAE 24° Flareless Thread PDF Download

Dash Size Nominal Size Threads per In. Male Thread O.D. Female Thread I.D.
-4 7/16 20 7/16 25/64
-5 1/2 20 1/2 29/64
-6 9/16 18 9/16 1/2
-8 3/4 16 3/4 11/16
-10 7/8 14 7/8 13/16
-12 1-1/16 12 1-1/16 31/32
-16 1-5/16 12 1-5/16 1-15/64
-20 1-5/8 12 1-5/8 1-35/64
-24 1-7/8 12 1-7/8 1-51/64
-32 2-1/2 12 2-1/2 2-27/64

SAE Straight Thread with O-Ring (ORB) PDF Download

Dash Size Nominal Size Threads per In. Male Thread O.D. Female Thread I.D.
-4 7/16 20 7/16 25/64
-5 1/2 20 1/2 29/64
-6 9/16 18 9/16 1/2
-8 3/4 16 3/4 11/16
-10 7/8 14 7/8 13/16
-12 1-1/16 12 1-1/16 1-63/64
-16 1-5/16 12 1-5/16 1-15/64
-20 1-5/8 12 1-5/8 1-35/64
-24 1-7/8 12 1-7/8 1-51/64
-32 2-1/2 12 2-1/2 2-27/64

SAE Flat Face O-Ring (ORFS) PDF Download

Dash Size Nominal Size Threads per In. Male Thread O.D. Female Thread I.D.
-4 9/16 18 9/16 1/2
-6 11/16 16 11/16 5/8
-8 13/16 16 13/16 3/4
-10 1 14 1 15/16
-12 1-3/16 12 1-3/16 1-3/32
-16 1-7/16 12 1-7/16 1-11/32
-20 1-11/16 12 1-11/16 1-19/32
-24 2 12 2 1-29/32

SAE Thread with 45° Flare PDF Download

Dash Size Nominal Size Threads per In. Male Thread O.D. Female Thread I.D.
-4 7/16 20 7/16 25/64
-5 1/2 20 1/2 29/64
-6 5/8 18 5/8 9/16
-8 3/4 16 3/4 11/16
-10 7/8 14 7/8 13/16
-12 1-1/16 14 1-1/16 63/64

JIC (SAE Thread with 37° Flare) PDF Download

Nom. Tube O.D. (in.)

Dash Size

Nominal Size
Threads per In.
Male Thread O.D.
Female Thread I.D.
1/8
-2
5/16
24
5/16
17/64
3/16
-3
3/8
24
3/8
21/64
1/4
-4
7/16
20
7/16
25/64
5/16
-5
1/2
20
1/2
29/64
3/8
-6
9/16
18
9/16
1/2
1/2
-8
3/4
16
3/4
11/16
5/8
-10
7/8
14
7/8
13/16
3/4
-12
1-1/16
12
1-1/16
31/32
1
-16
1-5/16
12
1-5/16
1-15/64
1 1/4
-20
1-5/8
12
1-5/8
1-35/64
1 1/2
-24
1-7/8
12
1-7/8
1-51/64
2
-32
2-1/2
12
2-1/2
2-27/64
 

3000# Code 61 Flange PDF Download

Dash Size

Flange O.D.
Flange Thickness
-8
1-3/16
.265
-10 **
1.338 [34mm]
.276
-12
1-1/2
.270
-16
1-3/4
.320
-20
2
.322
-24
2-3/8
.325
-32
2-13/16
.390
** Komatsu

6000# Code 62 Flange PDF Download

Dash Size

Flange O.D.
Flange Thickness
-8
1-1/4
.312
-12
1-5/8
.348
-16
1-7/8
.380
-20
2-1/8
.420
-24
2-1/2
.500
-32
3-1/8
.500