Pressure Instruments – Bellows

A bellows pressure element expands when pressure is applied to the inside, actuating an indicator, transmitter or controller. Bellows elements are generally used in pressure ranges from 0 to 10 inches H2O and from 0 to 10 psig, and for vacuum ranges from 10 to 20 inches H2O. In pneumatic instruments, bellows usually operate at approximately 3 to 15 psig.