The Model BQ back pressure regulator is designed for lower flow installations to control flow rates not covered by Model 123. It is often used in economizer circuits. It is also a popular cryogenic regulator and widely used in chemical process services.
Cashco manufactures a proprietary line of self-contained regulators and control valves. The regulators are self-sufficient valves that control the flow based on line pressure at the regulator. By contrast, control valves control flow based on an external signal coming from a controller. Cashco regulators control liquids and gases in industrial applications.