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British Standard Pipe Threads (BSPP, BSPF) PDF Download

Dash SizeNominal 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)
-11/16-28.0229.304.2812.25836.606.80
-21/8-28.0229.383.3601.33728.608.80
-41/4-19.0337.518.4843.450611.5011.80
-63/8-19.0337.656.6223.588615.0015.25
-81/2-14.0457.825.7793.733618.5019.00
-105/8-14.0457.902.8563.8106-21.00
-123/4-14.04571.041.9953.949624.0024.50
-147/8-14.04571.1891.14331.0976-23.25
-161-11.05821.3091.25081.192630.2530.75
-201 1/4-11.05821.6501.59181.533639.0039.50
-241 1/2-11.05821.8821.82381.765645.0045.00
-281 3/4-11 .05822.1162.05781.9996-51.00
-322-11.05822.3472.28882.230656.5057.00
-362 1/4-11 .05822.5872.52882.4706No Sizes of B.S. (British Standard) drills are recommended in B.S. 1157:1975 for this range
-402 1/2-11 .05822.9602.90182.8436
-442 3/4-11 .05823.2103.15183.0936
-483-11.05823.4603.40183.3436
-523 1/4-11 .05823.7003.64183.5836
-563 1/2-11 .05823.9503.89183.8336
-603 3/4-11 .05824.2004.14184.0836
-644-11.05824.4504.39184.3336
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 SeriesLL Series L Series S SeriesA SeriesAG SeriesDIN 7631 60 degree cone
4M 8 X 0.75M 8 X 1.0--------M 10 X 1.5----M 12 X 1.5
6M 10 X 1.0M 10 X 1.0M 12 X 1.5M 14 X 1.5M 12 X 1.5----M 14 X 1.5
8M 12 X 1.0M 12 X 1.0M 14 X 1.5M 16 X 1.5M 14 X 1.5----M 16 X 1.5
10M 14 X 1.0M 14 X 1.0M 16 X 1.5M 18 X 1.5M 16 X 1.5----M 18 X 1.5
12M 16 X 1.0M 16 X 1.0M 18 X 1.5M 20 X 1.5M 18 X 1.5----M 22 X 1.5
13--------------------M 20 X 1.5----
14M 18 X 1.0--------M 22 X 1.5M 20 X 1.5--------
15M 20 X 1.0----M 22 X 1.5----M 22 X 1.5--------
16M 22 X 1.0--------M 24 X 1.5M 24 X 1.5----M 26 X 1.5
17--------------------M 24 X 1.5----
18M 24 X 1.0----M 26 X 1.5----M 27 X 1.5--------
20M 25 X 1.0--------M 30 X 2.0M 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 2.0M 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 2.0M 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 2.0M 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 SizeNominal 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)
-11/16 - 27.0296.3125.2712.28126.30
-21/8 - 27.0296.405.3635.37368.70
-41/4 - 18.0444.540.4774.491611.10
-63/8 - 18.0444.675.6120.627014.50
-81/2 - 14.0571.840.7584.778418.00
-123/4 - 14.05711.050.9677.988923.25
-161 - 11-1/2.06961.3151.21361.238629.00
-201 1/4 - 11-1/2.06961.6601.55711.583438.00
-241 1/2 - 11-1/2.06961.9001.79611.822344.00
-322 - 11-1/2.06962.3752.26902.296356.00
-402 1/2 - 8.10002.8752.71952.762267.00
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 SizeNominal Size Threads per In.Male Thread O.D.Female Thread I.D.
-47/16207/1625/64
-51/2201/229/64
-69/16189/161/2
-83/4163/411/16
-107/8147/813/16
-121-1/16121-1/1631/32
-161-5/16121-5/161-15/64
-201-5/8121-5/81-35/64
-241-7/8121-7/81-51/64
-322-1/2122-1/22-27/64

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

Dash SizeNominal Size Threads per In.Male Thread O.D.Female Thread I.D.
-47/16207/1625/64
-51/2201/229/64
-69/16189/161/2
-83/4163/411/16
-107/8147/813/16
-121-1/16121-1/161-63/64
-161-5/16121-5/161-15/64
-201-5/8121-5/81-35/64
-241-7/8121-7/81-51/64
-322-1/2122-1/22-27/64

SAE Flat Face O-Ring (ORFS) PDF Download

Dash SizeNominal Size Threads per In.Male Thread O.D.Female Thread I.D.
-49/16189/161/2
-611/161611/165/8
-813/161613/163/4
-10114115/16
-121-3/16121-3/161-3/32
-161-7/16121-7/161-11/32
-201-11/16121-11/161-19/32
-2421221-29/32

SAE Thread with 45° Flare PDF Download

Dash SizeNominal Size Threads per In.Male Thread O.D.Female Thread I.D.
-47/16207/1625/64
-51/2201/229/64
-65/8185/89/16
-83/4163/411/16
-107/8147/813/16
-121-1/16141-1/1663/64

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