Type 77 industrial vacuum pressure regulator monitors and controls pressures from 29 in.-Hg vacuum to 150 psi. It offers flow capacities to 40 scfm. Fixed negative 15 psig bias spring maintains vacuum outputs and controls system pressure. Adjustable opposing range spring increases controlled pressure outputs. They are available with 1⁄4 or 3⁄8 NPT and 1⁄4 or 3⁄8 BSPT port size. Balanced supply valve keeps output virtually unaffected by supply pressure changes. Stack-up construction allows for disassembly and repair without disconnecting from air line.
They feature aluminum die-cast construction with weather-resistant vinyl paint finish. Output pressure droop under varying downstream flow conditions is minimized by aspirator tube, which adjusts the air supply valve opening in accordance with flow velocity. The dampening action of the aspirator tube maintains continuous and stable output pressure.
It provides precise vacuum pressure control within sub-atmospheric monitoring applications. It can be installed upstream or downstream from the vacuum pump. Upstream installation is preferred for applications in which the rapid evacuation of a vessel or system is required, because pump exhaust capacity is normally greater than that of the regulator. In all other applications, the regulator can be located between the pump and the vessel. Units may be either pipe-, panel- or bracket-mounted to suit particular application needs.
The Precision Controls Division of Marsh Bellofram Corp., (304) 387-1200, www.marshbellofram.com