PNEUMATIC AIR RELAY (Type 72 HR)

Type 72 and Type 72HR Positive Bias Booster Pneumatic Air Relays are positive bias booster pneumatic relays are used when high flow capacity is required. Offered in four adjustable ranges with exceptionally high flow capacity of up to 50 SCFM (1400 LPM) with minimal pressure droop, output pressure of the Type 72 & Type 72HR are accurately maintained under varying flow conditions by means of an aspirator tube, which adjusts the air supply valve opening in proportion to flow velocity.

A balanced supply valve utilizing a Bellofram patented internal rolling diaphragm makes the relay virtually immune to changes in supply pressure, while offering reliable performance over millions of cycles. Simple design makes maintenance easy, and the relay can be serviced without removing it from the line. The standard signal-to-output ratio is 1:1, but 1:2, 1:4 and 1:6 ratios are available on special request. An optional high-relief version (72HR) is also available.