Use of go-no go fixed gauges:
Use two ring gauges separately to screw on the external thread to be detected (in any order).
(1) However, the middle diameter of the thread is large, and the product is not qualified.
(2) The stop gauge is passed, the middle diameter is small, and the product is unqualified.
(3) The pass gauge can rotate freely at any position of the thread, the stop gauge is twisted one to two or three rings, and may sometimes be twisted one or two more rings, but the thread head is not screwed out of the ring gauge end face, which indicates that the diameter of the external thread detected is just in the "tolerance zone", which is a qualified product.
A go/no-go gauge refers to an inspection tool used to check a workpiece against its allowed tolerances via a go/no-go test. Its name is derived from two tests: the check involves the workpiece having to pass one test (go) and fail the other (no-go).
A go/no-go gauge is an integral part of the quality process that is used in the manufacturing industry to ensure interchangeability of parts between processes or even between different manufacturers. It does not return a size or actual measurement in the conventional sense, but instead returns a state, which is either acceptable (the part is within tolerance and may be used) or unacceptable (the part must be rejected).
