Yeary Controls Multi-Port Resistance Plates are custom fabricated to meet individual flow, pressure and noise requirements. Depending on the fluid type and pressure drop ratio, the plates may be up to four stages, though most common are one or two stage plates. Our diffusers are usually made from ASTM 304, or 316 Stainless Steel plate for installation between standard raised face flanges. Other materials of construction are available on request.

Usually, resistance plates are added downstream of control valves and absorb up to 85% of the required pressure drop at MAX conditions They do this by creating backpressure on the valve which allows the control valve to operate within its most efficient range of control in services that exceed the ability of the valve to meet noise and  cavitation limits.

Resistance plates may be used for number of reasons. Such as when the valve Mach Number (valve outlet velocity) is too high and must be slowed down by creating backpressure through the diffuser plate, or when cavitating liquids might otherwise cause noise, or damage to the control valve and downstream piping.

Current Installations include pump bypass control, pipeline start-up, liquid and gas pressure reducing stations, downstream of steam pressure reducing valves, gas vent and flare systems, turbo expander bypass.