This part of this BS 3643 specifies the fundamental deviations,
tolerances and limits of size for the tolerance classes 4H, 5H, 6H and
7H for internal threads and 4h, 6g and 8g for external threads where
appropriate for:
• a coarse pitch series with the range 1 mm to 68 mm diameter;
• a fine pitch series with the range 1 mm to 33 mm diameter;
• a constant pitch series with the range 8 mm to 300 mm diameter.
For certain diameter/pitch combinations, the fundamental deviations,
tolerances and limits of size for tolerance class 4H for internal threads
and tolerance classes 6h and 4g for external threads, primarily for
aerospace use, are specified in Annex A.
BS 3643-2:2007 history
0000 BS 3643-2:2007(2014)
2007BS 3643-2:2007 ISO metric screw threads Part 2: Specification for selected limits of size
1981BS 3643-2:1981 ISO metric screw threads - Specification for selected limits of size