Thread ring gauges for G pipe thread (BSP)

G is the parallel British pipe thread. It does not seal in the thread itself but through a gasket on the seating face, which is why diameter and pitch stay the same over the whole length. A ring gauge checks an external thread on the same principle as a plug gauge checks an internal one: the go ring must run on, the no-go ring must not.

VÖLKEL offers 38 versions, from G 1/8 x 28 to G 4" x 11.