BS 3643-1:2007

This part of BS 3643 gives a compilation of principles and basic data for single-start, parallel screw threads having the ISO basic profile for triangular screw threads.

The clauses in this standard have been so arranged that each relates directly to the relevant ISO standard. Each clause maintains as far as possible the ISO format, to enable direct cross reference with the ISO standards.

BS 3643-1:2007 contains:

• Terms and definitions and symbols
• Basic profile
• General plan
• Basic dimensions
• Tolerances – Principles and basic data
• Tolerances – Deviations for constructional thread
• Tolerances – Limits of sizes for hot-dip galvanized external screw threads to mate with internal screw threads tapped with tolerance position H or G after galvanizing
• Tolerances – Limits of sizes for internal screw threads to mate with hot-dip galvanized external screw threads with maximum size of tolerance position h before galvanizing

This part of BS 3643 supersedes BS 3643-1:1981, which is withdrawn.

This part of BS 3643 has been revised to bring it up to date. The 1981edition of the standard was based on ISO 68:1963, ISO 261:1973, ISO 724:1968, ISO 965-1:1980 and ISO 965-3:1980. These standards have all been withdrawn and superseded and this part of BS 3643 has been revised to reflect the latest editions of these standards