BSPP Thread Ring Gages

Thread Check Inc. offers a complete line of British parallel pipe threads per ISO 228 and BS ‐2779. In March 2003 the British Standards Institute withdrew BS‐2779 and replaced it with ISO‐228. ISO 228 ‐ 1 covers pipe threads where pressure‐tight joints are not made on the threads. ISO 228 ‐ 2 covers the limit gages for pipe threads where pressure‐tight joints are not made on the threads. ISO 1179, pipe connection, threaded to ISO 228‐1 and gauged with ISO 228 ‐ 2 gauges for plain end steel and other metal tubes in industrial applications. BSPP Thread gages have a 55 degree thread profile. The specification covers several Go and several No Go gauges designed to verify different elements of the thread. The threaded Go gages ensure that the profile of the machined piece does not exceed the maximum of material provided for by the tolerances applied to the dimensions of the profile defined by ISO 228‐1. The threaded No Go gauges for the threads of the pieces fix the minimum material limit on the flanks of the thread. Thread Check offers both the full form style as called out in the ISO specification as well as a modified version manufactured in the U.S.A. Full form thread ring gages are designed in a solid style and may be calibrated with a wear check plug gage. Ring gages are available in Class A and B. Class A Go ring gages are also valid for class B threads. No Go class B rings are quoted as special. Thread Check’s expert sales engineer can assist you with selecting the correct gauges for your application.

All British gages include a calibration certificate.

go no go gauges