Low pressure reducing valve ZM-R/N50, SST

Negative pressure reducing valve (N)

Description

Low pressure reducing valves control secondary pressure (p2, behind valve). Low pressure reducing valves ZM-R/N50 are controlling protective gas or inert gas to isolate processes from contamination by atmospheric oxygen.

Technology

ZM-R/N50 is a spring loaded differential pressure regulator with reference to actual atmospheric pressure via a sensor hole to ambient. Under non operating conditions, the atmospheric pressure the adjustable range spring and a stem hold the double-valve open. Under operating conditions, gas enters from primary (p1) through the valve and reaches counter side of diaphragm via a pulse line. As a result, the differential pressure is exactly in balance with the force of adjustable range spring. Double-valve will be closed as soon as secondary pressure (p2) raises set point of adjustable range screw . Valves will be open again, with secondary pressure below set point. Valves seat tightness is at least according to VDI/VDE 2174. The pulse line is compensating dynamic pressure drop. Best performance with pick-up directly on process or at least 300 mm behind unit. Optional D-connection is used for pilot line connection in case of dome loaded service (high pressure blanketing). ZM-R/N50 is vacuum-proof, manufactured in decreasing design and uses no external energy. ZM-R/N50 units are performing with connected pulse line only.

Application

The low pressure reducer ZM-R/N works under vacuum conditions with back
pressure (p2) slightly below atmospheric pressure. Pressure ranges vary between -80 mbar relative and +5 mbar relative. ZM-R/N50 is a perfect pressure reducer for inertization applications under vacuum conditions.