Conical thread ring gauge inspection: standard temperature of 20 ° C, standard condition with zero force measurement. The single diameter of the threaded plug gauge is measured using a "three needle method" on a length gauge. Use a tool microscope to detect pitch, half angle, small diameter, and clearance grooves. The threaded ring gauge (T) is inspected with calibrated plug gauges TT and TZ at the through end; Check the end (Z) with calibrated plug gauges ZT and ZZ; Ensure the pitch and half angle with machining tools.

Use of thread plug gauges: A. Production workshops use new or less worn through end thread plug gauges and near worn end thread plug gauges; The acceptance department uses nearly worn through end thread plug gauges and new or less worn end thread plug gauges. B. If the thread plug gauge that determines the qualified working thread meets the corresponding standard, then the working thread is qualified. C. There are no other agreements, and the acceptance of thread ring gauges shall be based on the verification of thread plug gauges, and shall comply with the provisions of Articles A and B.