Gas Applications
The Equilibar® back pressure regulator (BPR) is well suited for a variety of gas applications. With its precision performance across a wide range of flow rates and its superior accuracy at low flow rates and low pressure setpoints, the Equilibar BPR is an excellent choice for a number of critical gas control applications such as:
- Tank blanketing
- Gas chromatography
- Sanitary tank blanketing
- Cryogenics using helium gas
- Oxygen and hydrogen pressure control in electrolysis
Because the Equilibar BPR is dome-loaded and gets its setpoint from the pressure exerted its dome, the setpoint can be positive pressure, atmosphere or vacuum pressure. Equilibar vacuum regulators (EVR) work similarly to the BPR, but use a vacuum regulator to set the pilot pressure on the dome. Because of its wide flow range and fast response, EVRs are also used in a wide variety of vacuum applications.
Equilibar Gas Application Highlights
Precision Gas Pressure Supply: Substitution for Standard Pressure Regulator
At low to medium gas flowrates, it is possible to place the Equilibar BPR into applications that normally call for a standard pressure regulator. By placing a flow restrictor upstream of the Equilibar®, any excess flow not required by the application is simply vented by the regulator.
The resulting precision significantly exceeds that of standard pressure regulators. This approach is especially economical for compressed air and low flow rates of other gases.
A variable area flowmeter with needle valve (i.e. “rotameter”) is typically recommended for the flow restricting device. The optimum setpoint for the rotameter is just greater than the maximum flow rate anticipated by the application. The overall consumption of gas is therefore approximately equal to the maximum requirement of the application.
Nitrogen Padding: Process Vessel Pressure Control
The Equilibar® Pressure Regulator is ideally suited to precisely control the pressure in a process vessel. Today’s Process industry requires quick and reliable control of process pressures from centralized or distributed control systems.
There are many situations in the Chemical Industry where nitrogen or other gases are metered into the gas space of process vessels to minimize oxidation or moisture contamination.
The Equilibar® is able to precisely control the resulting pressure in the vessel by precisely controlling the outflow to match the reference pressure. This reference can be supplied by a manually controlled regulator or an electro-pneumatic regulator for computer automation of vessel pressure.
Relief Valve: 2-way Process Vessel Pressure Control
The Equilibar® Pressure Regulator is ideally suited to precisely control the pressure in a process vessel. Today’s Process industry requires quick and reliable control of process pressures from centralized or distributed control systems.
While electro-pneumatic transducers do a good job of sending air pressure to a process vessel, things can get very sticky when the process vessel needs relieving. First of all, E/P transducers have very limited sensitivity and capacity in the relief mode. Second, you don’t want foam, mist, liquid overflow, or corrosive vapors getting back into these expensive devices.
The Equilibar® pressure regulator can work with your E/P transducer to provide an exceptionally robust and sensitive vessel pressure control system.
GloveBox Pressure Control: HVAC Control
The Equilibar® is now available in a lightweight HVAC style that is perfect for controlling positive chamber pressure in gloveboxes and other critical process environments.
In the schematic at right, a rotameter is used to control gas in flow into a glovebox or positive pressure chamber. A set-point regulator is used to provide a precision set-point for the Equilibar Precision Back Pressure Regulator. Equilibar offers set-point regulators that control from 0.25 in H20 (0.01 psig / .68 bar(g)) up to 500 psig / 34 bar(g).
An electro pneumatic regulator can provide easy computer automation for the pressure set-point, as shown in the second diagram at right. A small blower is shown as gas supply.
See also:
- BioGas Generator uses Equilibar to improve engine control.
- Fuel Cell and Fuel Cell Testing Applications page.
Contact our engineers to discuss your unique application.
