Which of the following is best gauge/machine to inspect the parallel screw ring gauges?

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ALP CBT 2 Fitter Previous Paper: Held on 23 Jan 2019 Shift 1

Answer 1

Explanation:

Limit gauges are used in inspection because they provide a quick means of checking.
The Go and No-Go principals of gauging are that the Go-end of the gauge must go into the feature of the component being checked and the NOGO end must not go into the same feature.
There are various measuring instruments used for checking the thread.

Screw pitch gauge	Used to check the pitch of external and internal threads
Screw thread plug gauge	Used to check the internal threads
Screw thread ring gauge	Used to check the external thread for its accuracy
Screw thread calliper gauge	Used for checking external threads. This is a highly efficient type gauge and uses more than ring gauge.

Fitter 34 20Q Hindi - Final images q13b

Pitch Diameter Measurement of Ring gauge

The measurement of the pitch diameter of individual ring screw gauges is undertaken only when necessary. Instead, they use of check plugs is quicker and preferred.
The direct mechanical measurement of the pitch diameter of parallel screw ring gauges is practeciable only by the use of measuring machines of special design.
The NPL displacement method is used for measuring the pitch diameter of internal screw threads.
The basis is to measure the pitch diameter of a screw ring gauge by comparison with the "Pitch diameter" of a precision annular grooves in a solid cylindrical plug, i.e. comparators are used to inspect the parallel screw ring gauges