How it works – Equilibar back pressure regulators explained

Introduction to the operating principle of Equilibar® back pressure regulators

Watch this explanatory animation on Youtube – with German or English subtitles! 

Browse our product categories to find more in-depth information about the various types of back pressure regulators that we offer. 

Feel free to contact us for a quotation or trial delivery and convince yourself. We will help you configure the optimal product solution for your process requirements and pressure challenge!

Diaphragm sealed control valve

Equilibar dome-loaded back pressure regulators operate by using a diaphragm that acts as a seal: A reference pressure is set on the diaphragm, which pushes the diaphragm down to close the orifices. As long as the set pressure is higher than the inlet pressure, it remains sealed. When the pressure at the inlet exceeds the pressure set at the reference, the seating forces are overwhelmed and the diaphragm will lift to relieve pressure. The relieving pressure is just enough to maintain the pressure set at the dome in a tight equilibrium with the inlet pressure. This results in an incredibly fast response as well as high precision in maintaining the process pressure at the required level.

Unique pressure control features

Equilibar dome-loaded back pressure regulators offer high precision, repeatability, and reproducibility.

These back pressure regulators maintain the upstream pressure at their own inlet. They use patented technology to enable high precision and stability for controlling the pressure of your process. The regulators are particularly suitable for extreme temperatures, mixed-phase fluids, corrosive media and sanitary applications. Depending on process conditions, a wide range of materials is available for the body and the diaphragm. For the diaphragm this includes for example (glass reinforced) PTFE, stainless steel 316, Hastelloy, zirconium, and more. For the body, we can offer the same, along with other polymeric materials. Because of this, the performance of the Equilibar back pressure regulator is unparalleled in the industry!

The back pressure regulator typically holds its upstream pressure within 0.2% to 0.5% of the applied reference. Setting a stable reference pressure is key to get the most out of the performance of your back pressure regulator and thus the best performance of your process.

Applicable for demanding and even unknown process conditions

In practice, the conditions under which future processes will operate are often unknown when preparing to build such an application. Equilibar back pressure regulators can be operated with broad variations in design specifications and therefore enable a wide variety of process parameters.

Visit our products overview page on back pressure regulators to read more about the outstanding performance of our products compared to traditional devices and visit our applications page to learn more about the wide range of applications in which our products are being used.

Manual or electronic pressure control

There are different methods on how to supply the reference pressure to your dome-loaded back pressure regulator. First, it is good to know that the compressibility of the media that you use in the reference helps to get good performance. The most common methods are therefore based on applying a gas as a pilot media. In some applications, liquids can be used.

The precision of the Equilibar back pressure regulator is furthermore defined by the accuracy of the reference set-point on the dome. The reference set-point pressure can be applied by means of a manual forward pressure reducing regulator or an electronic pressure controller (single valve or dual valve, read more here). Electronic regulators provide more flexibility and the most accurate result, compared to manual regulators.

In sophisticated pilot plant and R&D processes where maximum performance, stability, accuracy, and reproducibility are required, we recommend closed-loop control between the actual process pressure and the reference pressure. Contact us for more information on closed-loop control.

In the video below we demonstrate using a (manual) forward pressure reducing regulator to set the pressure. This is connected to the reference port of the back pressure regulator and sets the required pressure on the dome of the back pressure regulator. The explanation for this can be seen from 0:33 to 0:43.