Back Pressure Regulators for Liquid Pressures

Liquid Pump Applications

The Equilibar® back pressure regulator offers many advantages for liquid pressure control in the industrial environment.

The elegance and simplicity of the device’s design make it highly suitable for corrosive or sanitary applications.

Its unparalleled precision and ultra fast response time make it highly suitable for closed-loop process control systems by utilizing an electro-pneumatic regulator.

liquid back pressure regulator

Pump Pressure Control
(Coating, Injection, Dosing, etc.)

The Equilibar® back pressure regulator can be used in concert with low-cost pumps to provide a sophisticated pressure control system. This pressure regulator can be placed in a recirculating loop with virtually any type of pump to allow your control system to explicitly command system pressure. Or use a fixed reference pressure signal for precisely constant pressure across widely varying flow rates.

Typical pump pressure control applications:

  • Precision spray coating
  • Precision die coating
  • Hydraulic test stands
  • Military avionics test stands
  • Industrial pump recirculation control

See also discussion of pressure bypass regulators and high resolution flow control valves.

pump pressure control regulator schematic

Raising Pump Discharge Pressure

Often centrifugal pumps cannot be used to stop the flow of fluid because of high supply head pressures. In other applications, VFD drives (variable frequency drives)cannot control the pump to low discharge flow rates because the output pressure of the pump is too low.

In these cases and Equilibar back pressure regulator is used to raise the pump’s output head to always exceed its supply head.

back pressure valve used to raise pump dischage head

Precision Control with Closed Loop Control

( Electro-Pneumatic Regulator w/ External Feedback)

For most applications, the Equilibar is precise enough to be used with a simple set-point pressure input. However, for some automation applications, it is useful to have closed loop control using an external pressure transmitter. By using an electronic pressure regulator  (E/P, I/P) with external feedback, it is possible to match the reading of your process pressure transmitter exactly to your desired set-point.

The Equilibar provides numerous benefits over traditional control valves in these closed-loop applications. Such benefits include extremely wide flow range, ultra fast reaction times, and ease of PID tuning.

electronic back pressure regulator with closed loop control

Automatic Vessel Level Control

The precision and simplicity of the Equilibar make it ideal to control the level in vessels and baths. For example, a 60 inch aqueous level could easily be achieved from a batch control recipe by sending a 2.2 psi reference signal to the Equilibar. This provides a particularly elegant solution for automatic bath level control system where persistent water inflows are present.

automatic vessel level control regulator

Shear Sensitive Fluid Handling

The Equilibar® pressure regulator can tackle tough shear sensitive fluids and dispersions where traditional fluid controls fail. The elastomeric diaphragm throttles fluid pressure in a less abrupt manner than traditional valve seats. The self adjusting nature of the membrane valve seat allows the valve to easily ingest and pass particulate matter.

The biggest advantage of this device for shear sensitive applications, however, is how this devices complements the strengths of diaphragm pumps. These pumps excel in the handling of shear sensitive fluids, emulsions, and dispersions. However, problems with pulsation and output pressure make these pumps difficult to use in automated applications. The Equilibar® Pressure Regulator not only controls the pressure of these sensitive solutions, but also modulates the pressure pulsations.. The result is an extremely elegant and cost-effective solution for handling these difficult solutions.

shear sensitive fluid