Equilibar Flow Control | Precision Fluid Control Valves
  • fr
  • de
  • ja
  • es
  • ar
  • ar
  • ar

Equilibar Flow Control Valves

Precision Control Valves for Research and Industry

Precision control across an ultra-wide range of flow rates
for gases, liquids and mixed phase fluids.


The Equilibar® valve is a precision back pressure regulator that is easily configured to control flow in a control loop with an electronic controller and a flow meter. For demanding flow control applications where the supply pressure is largely stable, Equilibar customers have discovered significant benefits including wide Cv range capability, chemical compatibility and multiphase fluid handling.

How it Works

In a flow control configuration, the Equilibar® valve works with an electronic pilot pressure controller and a flow meter in a control loop. A proportional-integral-derivative (PID) controller monitors input from a flow transmitter (FT) and adjusts the pilot pressure to bring flow under control. An electro-pneumatic (E/P) pressure controller translates the electronic signal from the PID into a pressure signal for the pilot pressure. Flow is decreased by raising the pilot pressure and increased by lowering the pilot pressure.

schematic of how equilibar back pressure regulator works in flow control

An Equilibar flow control valve works in a PID control loop with a flow meter and an electronic pressure controller.

In this setup, and increase in actuation pressure decreases the flow so the PID control scheme will be set up differently than if using a traditional control valve. In flow control operations with an Equilibar valve, the PID controller must be used in direct mode instead of the more common inverse mode, because pressure must be increased in response to an increase in flow (see graph at right).

Equilibar flow control valve

An Equilibar GSD4 is paired with an electronic pilot regulator for use in flow control applications

Download a BrochureSpeak to an Engineer


Flow Response to Actuation Pressure for a Traditional Flow Control Valve and an Equilibar Valve

Graph showing opposite responses of a traditional globe valve (red) and an Equilibar valve (blue) in response to actuation pressure

Watch a video of flow control using Equilibar valves

When to Consider Using an Equilibar Valve for Flow Control

The Equilibar fluid control valve is well suited for demanding application requirements including:

  • Flow coefficient (Cv) ranges wider than traditional valves (>100:1)
  • Highly corrosive gases and liquids (available in exotic alloy bodies and diaphragms with FFKM)
  • High temperature (seals available up to 500ºC)
  • Sanitary and biopharmaceutical applications (available with USP Class VI diaphragms)
  • Extremely low flow rates (controls Cv down to 1E-9)
  • Two-phase, phase-change and supercritical states
  • Extremely low DP and extremely high DP

Contact an Equilibar engineer to discuss your flow control application today.

Application Pages Download a Brochure Contact Us

March 2019 Flow Control Magazine

Read our article in Flow control Magazine “Considering innovative direct-sealing diaphragm valves for highly demanding applications”

Valve Specifications

Equilibar flow control valve specifications

Equilibar News
interpret 2021

Q&A with Ryan Heffner following INTERPHEX, the conference for biopharmaceutical engineering

Equilibar’s Ryan Heffner and Jeff Jennings recently returned from the INTERPHEX global conference in New York City.  This was the first major conference Equilibar has participated in since COVID arrived in early 2020. INTERPHEX focuses on the biopharmaceutical market, which has been in the spotlight for the past two years as multiple vaccines and medications Read More

Read More