Thread Geometry- British Standard Whitworth (BSW)

All Dimensions in inches unless otherwise stated

BSW Thread Geometry

d1 - Minor thread diameter male

d2 - Minor Thread diameter female

d3 - Pitch diameter

d4 - Major diameter

 
 
Thread Major Diameter Thread Per Inch Pitch Diameter Minor Diameter Male Thread
1/16 0.0625 60 0.0518 0.0413
3/32 0.0937 48 0.0804 0.0670
1/8 0.1250 40 0.1090 0.0930
5/32 0.1563 32 0.1362 0.1162
3/16 0.1875 24 0.1608 0.1341
7/32 0.2187 24 0.1920 0.1654
1/4 0.2500 20 0.2180 0.1860
5/16 0.3125 18 0.2769 0.2414
3/8 0.3750 16 0.3350 0.2950
7/16 0.4375 14 0.3918 0.3460

 

Thread Major Diameter Thread Per Inch Pitch Diameter Minor Diameter Male Thread
1/2 0.5000 12 0.4467 0.3933
9/16 0.5626 12 0.5091 0.4559
5/8 0.6250 11 0.5668 0.5086
3/4 0.7500 10 0.6860 0.6220
7/8 0.8750 9 0.8039 0.7327
1 1.0000 8 0.9200 0.8400
1 1/8 1.1250 7 1.0336 0.9421
1 1/4 1.2500 7 1.1586 1.0671
1 3/8 1.3750 6 1.2683 1.1616
1 1/2 1.5000 6 1.3933 1.2866

 

Thread Major Diameter Thread Per Inch Pitch Diameter Minor Diameter Male Thread
1 5/8 1.6251 5 1.4970 1.3689
1 3/4 1.7501 5 1.6220 1.4939
1 7/8 1.8751 4.5 1.7328 1.5905
2 2.0001 4.5 1.8578 1.7155
2 1/4 2.2501 4 2.0900 1.9299
2 1/2 2.5001 4 2.3400 2.1799
2 3/4 2.7501 3.5 2.5671 2.3842
3 3.0001 3.5 2.8172 2.6342
3 1/4 3.2501 3.25 3.0531 2.8561
3 1/2 3.5001 3.25 3.3031 3.1061

 

Thread Major Diameter Thread Per Inch Pitch Diameter Minor Diameter Male Thread
3 3/4 3.7502 3 3.5367 3.3232
4 4.0002 3 3.7867 3.5732
4 1/4 4.2502 2.875 4.0274 3.8047
4 1/2 4.5002 2.875 4.2774 4.0547
4 3/4 4.7506 2.75 4.5173 4.2766
5 5.0002 2.75 4.7673 4.5345
5 1/4 5.2502 2.625 5.0063 4.7623
5 1/2 5.5002 2.625 5.2563 5.0123
5 3/4 5.7502 2.5 5.4941 5.2379
6 6.0002 2.5 5.7441 5.4880


Note: Due to the fact that fastening applications differ greatly, the above information is for guidance only and is correct to the best of our knowledge. The customer must satisfy themselves with the performance of the fastener and validity of the data. TR Fastenings will not be held responsible for any failure that may occur from the use of this information.