Ref: BS 2779 - 1973, BS 21 - 1973, ISO R 228-1961, ISO R 7 - 1954, DIN 2999 -
1983. BSP: British Standard Pipe Thread - Parallel - Where pressure tight joints ...
Section 10 Useful Information BRITISH STANDARD PIPE THREADS Ref: BS 2779 - 1973, BS 21 - 1973, ISO R 228-1961, ISO R 7 - 1954, DIN 2999 - 1983 BSP: British Standard Pipe Thread - Parallel - Where pressure tight joints are obtained with a sealer ring BSPT: British Standard Pipe Tapered Thread - Where pressure tight joints are made on the threads
BRITISH ASSOCIATION SCREW THREAD - MINIATURE BA Form - Ref: BS 93 - 1951 BA = British Association Screw thread form is recommended for all screws smaller that 1/4 inch in diameter. In the selection of sizes, preference has been given to even numbered BA sizes. BA is symmetrical thread of 47 1/2 º. Crests and roots are rounded in equal radii. P = Pitch of thread, H = Dept of thread, R = Radius at root and crest, S = Root and crest truncation. H = 0.600 x P, R = 0.18083 x P, S = 0.26817 x P NOM. THREAD DESIGNATION
P PITCH mm
DEPTH OF THREAD mm
0 BA 1 BA 2 BA 3 BA 4 BA 5 BA 6 BA 8 BA 10 BA
1.00 0.90 0.91 0.73 0.66 0.59 0.53 0.43 0.35
0.60 0.54 0.48 0.44 0.39 0.35 0.32 0.26 0.21
BOLT AND NUT mm MAJOR DIA. 6.00 5.30 4.70 4.10 3.60 3.20 2.80 2.20 1.70
