Ring and Plug Thread Gauge

  • Manufactured from high quality alloy carbon steel
  • Heat treated and hardened to 58-60 HRC for optimal durability
  • Thread ring gauges are used to inspect external screw threads on shafts and spindles.
  • Thread plug gauges are used to inspect internal screw threads on bores.
  • Provided in sets of GO and NO-GO
  • Provided with calibration certificates traceable to National standards on request.
Ring and Plug Thread Gauge


Bearing Steel

Use of thread gauges

Thread gauges are used to inspect the screw threads of components and to ensure that they are within the permissible limits. Different gauges are available for different thread profiles like metric, unified, NPT, NPTF, Stub Acme, buttress, BSW, BSF, BA, BSP, BSCY etc. A thread ring gauge is used for checking the diametre and the pitch of threaded shafts whereas a plug gauge is used for the inspection of threaded bores. 

The thread gauges are supplied in sets of Go and No-Go. The Go gauge shall engage with the the threaded component without any excessive efforts whereas the No-Go shall not surpass the first three threads of the component. The threading on the component deems acceptable if it satisfies these two conditions.

Thread gauge standards

  • ACME: ANSI/ASME B1.5-1997
  • BA: BS 93-1951
  • BSCY: BS 811-1950
  • BSPP: IS:2643-2005
  • BSW/BSF: BS 84-2007
  • Buttress: BS 1657-1950
  • Metric: DIN 13-1999
  • NPT: ANSI/ASME B1.20.1-1983
  • Trapezoidal: ISO 7008-1988
  • Unified: BS 1580

Thread profiles

Some of the common thread profiles are shown below:

 Size  action
Metric sizes from 2mm-300mm