IS 2643 : 2018

Dimensions of Pipe Threads Where Pressure Tight Joints Are Not Made on the Threads

ISO 228-1
CurrentFrequently UsedSpecificationMEP · Plumbing Fixtures and Valves
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Summary

IS 2643 covers BSP parallel (G) threads for mechanical joints where sealing is by gasket or O-ring, not by thread interference. Complement to IS 554 (taper threads for pressure joints).

Specification for parallel (G) pipe threads where sealing is by gasket or washer, not by thread interference.

Key Values
Thread angle55° Whitworth
Thread typeParallel (G)
Size rangeG1/8 to G6
Practical Notes
! G threads seal by washer/O-ring, NOT by thread tightening. R (taper) threads from IS 554 seal by thread interference.
! Used for: hose connections, gauge ports, caps, and non-pressure joints.
! G threads mate with Rp (parallel internal) threads. Do NOT mate G external with R taper internal.
Cross-Referenced Codes
IS 554:1999Pipe Threads Where Pressure-Tight Joints Are ...
→
IS 2065:1996Code of Practice for Plumbing Services
→
pipe threadBSP parallelG threadmechanical joint