A pressure breakdown orifice is required to control the fluid flow rate for pump minimum bypass flow. This orifice is located at the pump discharge, prior to the pump bypass valve. Sizing is critical for protecting the centrifugal pump from overheating during pump operation.
Hunt Valve’s pressure breakdown orifices are specially designed for maximum life and ease of maintenance. These orifices are individually created to handle the pressure drop and pressure/flow rate requirements of each pump. A series of heat-treated stainless steel orifice plates are used to reduce the pressure from the inlet to the outlet. Each orifice plate is designed to provide a small pressure drop, which spreads the wear throughout the components. O-rings with Teflon™ back-up rings seal the orifice plates to the stainless steel housing. A stainless steel liner protects the piping from erosion due to the high-velocity turbulent flow exiting the orifice plates.
At Hunt Valve, each breakdown orifice assembly is designed for the customer’s specific application, considering inlet/outlet pressure and flow requirements. The following flange connections are available: ANSI, SAE 4-bolt or DIN. Special flanges and configurations can also be designed. Pressure test ports can be included to easily monitor wear. Installation is allowed in the horizontal or vertical position. The orifice assembly is mounted between piping flanges; no mounting brackets or additional supports are required.
The pressure breakdown orifice can be used in any application where the system pressure needs to be reduced at a constant rate with a constant flow. A typical descale system can include the breakdown orifice for both pump bypass and header pre-fill applications.