Gauges
Gauges are precision measuring instruments essential for quality control in fastener manufacturing. CYC supplies Thread Ring Gauges (Go/No-Go), Thread Plug Gauges, Plain Ring Gauges, Plain Plug Gauges, and specialized gauges for various thread standards — all calibrated to ensure accurate dimensional inspection.
Download Catalog (PDF)Gauge Types
Thread Plug Gauges
Taper Thread Ring Gauges
Thread Ring Gauges
Limit Gauges For Screw Thread
To determine thread standard and class of screw thread limit gauges, threads are tested by the two limit method GO and NOT GO system. For the NOT GO side there is a specified JIS method and standard, but no ISO classification.
Symbols of Gauges for Screw Thread
| Screw thread to be inspected | ISO | Current JIS | |||
|---|---|---|---|---|---|
| Gauge type | Symbol | Gauge type | Symbol | ||
External thread | Pitch diameter | Go screw ring gauge | GR | GO screw ring gauge | GR |
| Not go screw ring gauge | NR | NOT GO screw ring gauge for machine work | WE | ||
| NOT GO screw ring gauge for inspection | IR | ||||
| Major diameter | Plain GO ring gauge for major diameter | PR go | Limit snap gauge for machine work | WS | |
| Plain NOT GO ring gauge for major diameter | PR not-go | Limit snap gauge for inspection | IS | ||
Internal thread | Plain caliper gauge for major diameter | PC | |||
| Pitch diameter | GO screw plug gauge | GP | GO screw plug gauge | GP | |
| NOT GO screw plug gauge for machine work | WP | ||||
| NOT GO screw plug gauge | NP | NOT GO screw plug gauge for inspection | IP | ||
| Minor diameter | Plain plug gauge for minor diameter | PP | Limit plug gauge for machine work | WM | |
| Limit plug gauge for inspection | IM | ||||
Limit Gauges — Tolerance Position
Mutually related positions of external screw thread and internal screw thread limit gauge and gauge for checking explanation figure.
Example: M3 X 0.5 for ISO 6H 6g and current JIS class 2.
