MARYLAND METRICS
THREAD DATA CHARTS

PIPE THREAD -- BRITISH STANDARD PIPE PARALLEL -- BSPP/BSPF
PIPE THREAD -- JAPANESE PIPE PARALLEL -- PF
JAPANESE CONDUIT THREAD CTG (from 1/2" to 4")
British Pipe Thread ( Whitworth Form) -- Parallel (BSPP/BSPF) -- (G)

Click here to return to the thread data chart page index.

BS EN ISO 228-1: 2003 Table 1 Thread dimensions
British Pipe Thread ( Whitworth Form) -- Parallel (BSPP/BSPF) -- (G)

55 deg

  Tolerances on pitch diametera Tolerance on minor diameter Tolerance on major diameter
  Diameters Internal thread TD2 External thread Td2 Internal thread TD1 External thread Td
Desig-nation of thread Number of threads in 25.4 mm Pitch P Height of thread h major d = D pitch d2 = D2 minor d1 = D1 Lower deviation Upper deviation Lower deviation Class A Lower deviation Class B Upper deviation Lower deviation Upper deviation Lower deviation Upper deviation
1/16 28 0.907 0.581 7.723 7.142 6.561 0 0.107 -0.107 -0.214 0 0 0.282 -0.214 0
1/8 28 0.907 0.581 9.728 9.147 8.566 0 0.107 -0.107 -0.214 0 0 0.282 -0.214 0
1/4 19 1.337 0.856 13.157 12.301 11.445 0 0.125 -0.125 -0.25 0 0 0.445 -0.25 0
3/8 19 1.337 0.856 16.662 15.806 14.95 0 0.125 -0.125 -0.25 0 0 0.445 -0.25 0
1/2 14 1.814 1.162 20.955 19.793 18.631 0 0.142 -0.142 -0.284 0 0 0.541 -0.284 0
5/8 14 1.814 1.162 22.911 21.749 20.587 0 0.142 -0.142 -0.284 0 0 0.541 -0.284 0
3/4 14 1.814 1.162 26.441 25.279 24.117 0 0.142 -0.142 -0.284 0 0 0.541 -0.284 0
7/8 14 1.814 1.162 30.201 29.039 27.877 0 0.142 -0.142 -0.284 0 0 0.541 -0.284 0
1 11 2.309 1.479 33.249 31.77 30.291 0 0.18 -0.18 -0.36 0 0 0.64 -0.36 0
1 1/8 11 2.309 1.479 37.897 36.418 34.939 0 0.18 -0.18 -0.36 0 0 0.64 -0.36 0
1 1/4 11 2.309 1.479 41.91 40.431 38.952 0 0.18 -0.18 -0.36 0 0 0.64 -0.36 0
1 1/2 11 2.309 1.479 47.803 46.324 44.845 0 0.18 -0.18 -0.36 0 0 0.64 -0.36 0
1 3/4 11 2.309 1.479 53.746 52.267 50.788 0 0.18 -0.18 -0.36 0 0 0.64 -0.36 0
2 11 2.309 1.479 59.614 58.135 56.656 0 0.18 -0.18 -0.36 0 0 0.64 -0.36 0
2 1/4 11 2.309 1.479 65.71 64.231 62.752 0 0.217 -0.217 -0.434 0 0 0.64 -0.434 0
2 1/2 11 2.309 1.479 75.184 73.705 72.226 0 0.217 -0.217 -0.434 0 0 0.64 -0.434 0
2 3/4 11 2.309 1.479 81.534 80.055 78.576 0 0.217 -0.217 -0.434 0 0 0.64 -0.434 0
3 11 2.309 1.479 87.884 86.405 84.926 0 0.217 -0.217 -0.434 0 0 0.64 -0.434 0
3 1/2 11 2.309 1.479 100.33 98.851 97.372 0 0.217 -0.217 -0.434 0 0 0.64 -0.434 0
4 11 2.309 1.479 113.03 111.551 110.072 0 0.217 -0.217 -0.434 0 0 0.64 -0.434 0
4 1/2 11 2.309 1.479 125.73 124.251 122.772 0 0.217 -0.217 -0.434 0 0 0.64 -0.434 0
5 11 2.309 1.479 138.43 139.951 135.472 0 0.217 -0.217 -0.434 0 0 0.64 -0.434 0
5 1/2 11 2.309 1.479 151.13 149.651 148.172 0 0.217 -0.217 -0.434 0 0 0.64 -0.434 0
6 11 2.309 1.479 163.83 162.351 160.872 0 0.217 -0.217 -0.434 0 0 0.64 -0.434 0
Note: Class B applies only to external threads. Internal threads are Class A.
BS EN ISO 228-1: 2003 data chart above revised and updated 12/20/11



British Pipe Thread ( Whitworth Form) -- Parallel (BSPP/BSPF) -- (G)
55 deg

  Major Dia     External Thread   Internal Thread  
Size Size pitch     Major Dia Pitch Dia Minor Dia     Minor Dia Pitch Dia Major Dia Tap Drill
Thread
Designation
mm mm TPI Class Max Min Max Min Max Min   Class Min Max Min Max Min Max mm
G 1/16 7.723 0.907 28 A 7.723 7.509 7.142 7.035 6.561       6.561 6.834 7.142 7.249 7.723   6.8
G 1/16 7.723 0.907 28 B 7.723 7.509 7.142 6.928 6.561                    
G 1/8 9.728 0.907 28 A 9.728 9.514 9.147 9.040 8.566       8.566 8.848 9.147 9.254 9.728   8.8
G 1/8 9.728 0.907 28 B 9.728 9.514 9.147 8.933 8.566                    
G 1/4 13.157 1.337 19 A 13.157 12.907 12.301 12.176 11.445       11.445 11.89 12.301 12.426 13.157   11.8
G 1/4 13.157 1.337 19 B 13.157 12.907 12.301 12.051 11.445                    
G 3/8 16.662 1.337 19 A 16.662 16.412 15.806 15.681 14.950       14.95 15.395 15.806 15.931 16.662   15.25
G 3/8 16.662 1.337 19 B 16.662 16.412 15.806 15.556 14.950                    
G 1/2 20.955 1.814 14 A 20.955 20.671 19.793 19.651 18.631       18.631 19.172 19.793 19.935 20.955   19
G 1/2 20.955 1.814 14 B 20.955 20.671 19.793 19.509 18.631                    
G 5/8 22.911 1.814 14 A 22.911 22.627 21.749 21.607 20.587       20.587 21.128 21.749 21.891 22.911   21
G 5/8 22.911 1.814 14 B 22.911 22.627 21.749 21.465 20.587                    
G 3/4 26.441 1.814 14 A 26.441 26.157 25.279 25.137 24.117       24.117 24.658 25.279 25.421 26.441   24.5
G 3/4 26.441 1.814 14 B 26.441 26.157 25.279 24.995 24.117                    
G 7/8 30.201 1.814 14 A 30.201 29.917 29.039 28.897 27.877       27.877 28.418 29.039 29.181 30.201   28.25
G 7/8 30.201 1.814 14 B 30.201 29.917 29.039 28.755 27.877                    
G 1 33.249 2.309 11 A 33.249 32.889 31.770 31.590 30.291       30.291 30.931 31.77 31.95 33.249   30.75
G 1 33.249 2.309 11 B 33.249 32.889 31.770 31.410 30.291                    
G 1 1/8 37.897 2.309 11 A 37.897 37.537 36.418 36.238 34.939       34.939 35.579 36.418 36.598 37.897   35.5
G 1 1/8 37.897 2.309 11 B 37.897 37.537 36.418 36.058 34.939                    
G 1 1/4 41.910 2.309 11 A 41.910 41.550 40.431 40.251 38.952       38.952 39.592 40.431 40.611 41.910   39.5
G 1 1/4 41.910 2.309 11 B 41.910 41.550 40.431 40.071 38.952                    
G 1 3/8 44.323 2.309 11   44.323 limited data available 41.365 42.005 limited data available 41.75
G 1 1/2 47.803 2.309 11 A 47.803 47.443 46.324 46.144 44.845       44.845 45.485 46.324 46.504 47.803   45.25
G 1 1/2 47.803 2.309 11 B 47.803 47.443 46.324 45.964 44.845                    
G 1 5/8 52.000 2.309 11   52.000 limited data available 49.030 49.670 limited data available 49.5
G 1 3/4 53.746 2.309 11 A 53.746 53.386 52.267 52.087 50.788       50.788 51.428 52.267 52.447 53.746   51
G 1 3/4 53.746 2.309 11 B 53.746 53.386 52.267 51.907 50.788                    
G 2 59.614 2.309 11 A 59.614 59.254 58.135 57.955 56.656       56.656 57.296 58.135 58.315 59.614   57
G 2 59.614 2.309 11 B 59.614 59.254 58.135 57.775 56.656                    
G 2 1/4 65.710 2.309 11 A 65.710 65.276 64.231 64.014 62.752       62.752 63.392 64.231 64.448 65.710   63.3
G 2 1/4 65.710 2.309 11 B 65.710 65.276 64.231 63.797 62.752                    
G 2 1/2 75.184 2.309 11 A 75.184 74.750 73.705 73.488 72.226       72.226 72.866 73.705 73.922 75.184   72.8
G 2 1/2 75.184 2.309 11 B 75.184 74.750 73.705 73.271 72.226                    
G 2 3/4 81.534 2.309 11 A 81.534 81.100 80.055 79.838 78.576       78.576 79.216 80.055 80.272 81.534   79.1
G 2 3/4 81.534 2.309 11 B 81.534 81.100 80.055 79.621 78.576                    
G 3 87.884 2.309 11 A 87.884 87.450 86.405 86.188 84.926       84.926 85.566 86.405 86.622 87.884   85.5
G 3 87.884 2.309 11 B 87.884 87.450 86.405 85.971 84.926                    
G 3 1/4 93.980 2.309 11   93.984 limited data available 91.022 91.660 limited data available 91
G 3 1/2 100.330 2.309 11 A 100.330 99.896 98.851 98.634 97.372       97.372 98.012 98.851 99.068 100.330   97.75
G 3 1/2 100.330 2.309 11 B 100.330 99.896 98.851 98.417 97.372                    
G 3 3/4 106.680 2.309 11   106.680 limited data available 103.722 104.300 limited data available 104
G 4 113.030 2.309 11 A 113.030 112.596 111.551 111.334 110.072       110.072 110.712 111.551 111.768 113.030   110.5
G 4 113.030 2.309 11 B 113.030 112.596 111.551 111.117 110.072                    
G 4 1/2 125.730 2.309 11 A 125.730 125.296 124.251 124.034 122.772       122.772 123.412 124.251 124.468 125.730   123
G 4 1/2 125.730 2.309 11 B 125.730 125.296 124.251 123.817 122.772                    
G 5 138.430 2.309 11 A 138.430 137.996 136.951 136.734 135.472       135.472 136.112 136.951 137.168 138.430   136
G 5 138.430 2.309 11 B 138.430 137.996 136.951 136.517 135.472                    
G 5 1/2 151.130 2.309 11 A 151.130 150.696 149.651 149.434 148.172       148.172 148.812 149.651 149.868 151.130   148.5
G 5 1/2 151.130 2.309 11 B 151.130 150.696 149.651 149.217 148.172                    
G 6 163.830 2.309 11 A 163.830 163.396 162.351 162.134 160.872       160.872 161.512 162.351 162.568 163.830   161.5
G 6 163.830 2.309 11 B 163.830 163.396 162.351 161.917 160.872                    
Note: Class B applies only to external threads. Internal threads are Class A.
data chart above revised and updated 9/28/09


 

PIPE THREAD -- BRITISH STANDARD PIPE TAPER -- BSPT
PIPE THREAD -- JAPANESE PIPE TAPER -- PT
55 deg

MARYLAND METRICS -- THREAD DATA CHART:
British Pipe Thread ( Whitworth Form) -- Taper (BSPT) -- (R)
Thread Nominal Thread Major Pitch Threads Pitch Minor Thread Rounding Effective Tap
Designation Size Form Diameter mm per Diameter Diameter Height r Thread Drill
    Type mm p inch mm Male Thd. H1   Length mm Diameter
BSPT BSPT   d=D   tpi d2=D2 d3     External mm
R 1/16 1/16" BSPT 7.723 0.907 28 7.142 6.561 0.581 0.125 2.5 6.4
R 1/8 1/8" BSPT 9.728 0.907 28 9.147 8.566 0.581 0.125 2.5 8.4
R 1/4 1/4" BSPT 13.157 1.337 19 12.301 11.445 0.856 0.184 3.7 11.2
R 3/8 3/8" BSPT 16.662 1.337 19 15.806 14.95 0.856 0.184 3.7 14.75
R 1/2 1/2" BSPT 20.955 1.814 14 19.793 18.631 1.162 0.249 5 18.25
R 3/4 3/4" BSPT 26.441 1.814 14 25.279 24.117 1.162 0.249 5 23.75
R 1 1" BSPT 33.249 2.309 11 31.77 30.291 1.479 0.317 6.4 30
R 1 1/4 1 1/4" BSPT 41.91 2.309 11 40.431 38.952 1.479 0.317 6.4 38.5
R 1 1/2 1 1/2" BSPT 47.803 2.309 11 46.324 44.845 1.479 0.317 6.4 44.5
R 2 2" BSPT 59.614 2.309 11 58.135 56.656 1.479 0.317 7.5 56
R 2 1/2 2 1/2" BSPT 75.184 2.309 11 73.705 72.226 1.479 0.317 9.2 71
R 3 3" BSPT 87.884 2.309 11 86.405 84.926 1.479 0.317 9.2 85.5
R 4 4" BSPT 113.03 2.309 11 111.551 110.072 1.479 0.317 10.4 110.5
R 5 5" BSPT 138.43 2.309 11 136.951 135.472 1.479 0.317 11.5 136
R 6 6" BSPT 163.83 2.309 11 162.351 160.872 1.479 0.317 11.5 161.5
Click here to return to the thread data chart page index.

THINK!- MARYLAND METRICS - The One-Stop Source For Metric And British Sized Fasteners, Wrenches, Cutting, & Measuring Tools, Metal Shapes, Oil Seals, O-Rings, Mechanical Power Transmission Equipment, Bearings, Hydraulic And Pneumatic Fittings & Tubing, Workholding Components, Plumbing Fittings, & Some Electrical & Electronic Components. Click to go to Maryland Metrics home page


Phones: (800) 638-1830 or (410) 358-3130 are available Monday-Friday 8:30 AM to 5:30 PM Eastern time.
Faxes: (800) 872-9329 or (410) 358-3142 & E-mail are available anytime.
Warehouse & showroom hours are Monday-Friday 10 AM to 5:30 PM.
[ To: Maryland Metrics home page ] [ To: Maryland Metrics Product Guide ] [ e-mail to Maryland Metrics ]
Please note that all Trademarks and Tradenames are the property of their respective owners.
copyright 1998, 2000, 2001, 2002, 2006, 2007, 2009, 2011, 2012 maryland metrics -- all rights reserved -- ver gg22f thddat7.htm