High-pressure gas flow control
For gas flow control up to 200 bar, Bronkhorst has recently developed a new, directly driven control valve which makes mass flow controllers even more compact, offering even faster control.
Vary-P control valves have been available from Bronkhorst since 1985 for the control of high-pressure gas flow with high-pressure differences of up to 700 bar. The control valves – usually integrated in a mass flow controller (F-230 series) – are a more compact and much cheaper alternative to flow meters, which are combined with valves that are controlled pneumatically or using a servomotor. For controlling process pressure, Vary-P valves are often also applied in conjunction with Bronkhorst pressure meters. The Vary-P valve comprises a flow control section, along with a mechanism that keeps the differential pressure over this valve at a constant approx. 6 bar. As a result, the pressure at the inlet and outlet of the mass flow or pressure controller may vary without affecting the control performance. Industrial versions (IP65 rating) of all the company's mass flow controllers can also be supplied.>
Source: Control Engineering Europe - All Articles