GB/T 3934-2025 specifies the symbols, classification, thread profiles, tolerances, technical requirements, inspection and acceptance methods, marking, and packaging requirements for gauges used with general-purpose screw threads.
The standard applies to 60-degree thread gauges with nominal diameters from 1 mm to 300 mm and pitches from 0.2 mm to 8 mm. It covers thread plug gauges, thread ring gauges, checking gauges, smooth limit gauges, dimensional formulas, measurement conditions, hardness and surface roughness requirements, and workpiece thread conformity assessment.
This edition replaces GB/T 3934-2003 and includes updated terminology, usage rules, functional and control requirements, inspection parameters, ring gauge inspection provisions, and hardness requirements.
Application Scope: Manufacturing, inspection, calibration, and acceptance of general-purpose screw thread gauges and threaded workpieces in mechanical engineering and dimensional metrology.
