The Equilibar back pressure regulator can be used to reduce pulsations in circulating liquid systems, such as used with positive displacement pumps.
A very common use of back pressure regulators is to control pump pressure in a loop where a portion of the flow can be returned to the supply reservoir. The outlet pressure of any type of pump can easily be controlled in this manner. Where the pump is a positive displacement type, the higher pressure spikes will be preferentially reduced by the back pressure regulator due to its essential nature.
The Equilibar back pressure regulator uses very thin diaphragms loaded with compressible gas, making the device more sensitive to small changes in pressure than traditional spring-loaded BPRs. Most Equilibar BPRs are sensitive to pressure changes as small as 0.01% of overall set-point.
The Equilibar gas-loaded diaphragm also provides a very significant pulsation dampening effect just upstream of the valve orifice. Traditional pulsation dampeners consist of a flexible membrane (typically rubber) with a pre-loaded air charge on the non-wetted side. The Equilibar back pressure regulator provides a very similar geometry, allowing the diaphragm to absorb a portion of the pulsations through the very close agreement between the wetted fluid pressure and the gas charge pressure.
Integrated Lab Solutions addresses pulsation problem with LF Series Back Pressure Regulator
Berlin-based Integrated Lab Solutions, Gmbh (ILS) builds high-throughput test systems for catalyst research around the world. Project Leader Claudia Berger-Karin successfully addressed a critical challenge caused by pulsations coming from an HPLC pump in a liquid reactant injection system. A Bronkhorst Cori-flo mass flow controller was being used to control the injection, and the HPLC pump was needed only to supply the pressurized reactant. She replaced the spring-loaded back pressure regulator with Equilibar LF BPR and was able to remove virtually all of the flow variation in the system.