BSI - BS 84
Parallel Screw Threads of Whitworth Form
|Publication Date:||26 September 1956|
|ICS Code (Inch screw threads):||21.040.20|
Form of thread defined. Tables: basic sizes, limits, tolerances for 'class' bolts, nuts; BS Whitworth range, 1⁄8 in to 6 in; BS Fine range, 3⁄16 in to 43⁄16 in (limits and tolerances up to 3 in only). Also a Selected Thread series more suitable than BS Pipe parallel series for extra fine pitch applications. Appendices: limits, tolerances for B.S.W. and B.S.F. truncated bolts and nuts; bases of tolerances and allowances, formulae; effects of pitch and angle errors, acceptability of error combination; form of Whitworth crests; limits and tolerances for (non-preferred) 'close class' nuts.