Plug Gauge


  • "Go and No-Go" Gauge ( for Checking bores )
  • Double-ended Plug Gauge

Selection & Ordering

To select the right sizes of Smitra Plug Gauges considered these points :

  • Specify the diameters of the bores to be measured and their manufacturing tolerances. Once the tolerances are specified the Plug Gauge designs are automatically selected as per IS, BS, DIN standards.
  • Specify the Gauges are to be used to measure ' blind ' holes, so that necessary air vents can be provided to prevent air locks.

Ordering Example :

  • Smitra Plug Gauge : 35H7 + 0.2 / Double - ended / Non - Reversible / with Air Vent.
  • Smitra Plug Gauge : 15 + 0.35 / Double - ended / Reversible.

Description & Features

  • Made out of Superior Quality High Chrome Alloy Steel .
  • Quality Heat Treated and hardened to 58-60 HRC, to provide a High Degree of Wear Resistance.
  • Finely Lapped to get Maximum Seating & Surface Finish.
  • Sub-zero treated to Take Care of distortion throughout a Long & Stable Life Span of Gauges.

Common Uses

  • The Plug gauges are used to measure holes and bores which are to be manufactured within a given tolerance.
  • The Plug gauges can be used to measure both ' blind ' holes and ' through ' holes, however, for ' blind ' holes a groove is provided to prevent air locks.
  • The Plug Gauges are mainly used in areas of mass production where the bores ( of components ) are machined for interchangeable fit with male parts.

Scope of Supply

The Smitra Plug Gauges up to 40 mm delta are available with two Plug fitted at both the ends of an Aluminum handle. At one end of the "Go" plug is fitted, and to the other end the "no - go" plug. For easy identification, all "no-go" plugs are provided with a groove marking. Depending on the way plugs are fitted, a Plug Gauge can be either Reversible or Non Reversible.

The Plug Gauges from 40 mm delta to 80 mm delta are available with the two Plugs fitted on a steel handle with ball - locking arrangement.

The Plug Gauges above 80 mm delta are made in the form of segments and are known as segmental type Plug Gauges. The " GO " and " NO -GO " plugs are fitted on separate steel handles.

A pilot entry can also be provided to reduce wear when Gauges are used in bores of close tolerances.