Name different parts of a pressure gauge. Explain the use of hair spring in the pressure gauge.

Pressure gauge includes following components: a. ‘C’ type bourdon tube. b. Connecting link c. Sector gear d. Pinion Gear e. Hair spring f. Pointer g. DialUse of hair spring: Hair spring is responsible for controlling torque. It is also used to eliminate any play into linkages.

Main parts of Pressure gauge are Bourden Tube, Mechanical Link, Gear and Sector, Pinnion, Hair Spring, Dial, Pointer, Body, Inlet port etc

Purpose of hair spring is to push pointer back to zero when there is no pressure in tube and to reduce play between gears. It is also called as backlash spring.