British Standard Pipe Parallel ISO-228

The official name of the parallel pipe screw thread standard ISO 228 is: Pipe Threads Where Pressure-Tight Joints Are Not Made On The Threads.

This parallel pipe screw thread standard ISO 228 comes in two parts:
ISO 228; 2000: Part 1 Dimensions, Tolerances and Designation
ISO 228; 1987: Part 2 Verification by Means of Limit Gauges

Older standards that define the same thread are: BS 2779; DIN 2999.

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