PM-HF

The Pressure/vacuum relief valve Pressure/vacuum relief valve is an umbrella term that includes pressure or vacuum relief valve as well as pressure and vacuum relief valve. PROTEGO® Type PM-HF pilot-controlled diaphragm Diaphragm A diaphragm is a thin layer of material, which has a large surface area. valve is a highly developed valve for pressure and vacuum Vacuum Vacuum is the pressure in an enclosed space that is lower than the ambient pressure. relief. Primarily used as a device Device A device is a pipe component that influences the media flow by opening, closing, or partially shutting off the flow channel or by dividing or mixing the media flow. for outbreathing in tanks, vessels, and process engineering equipment Equipment Machines, appliances, fixed or mobile devices, control parts and accessories, and warning and prevention systems, whether separate or combined, intended for the generation, transfer, storage, measurement, control, and conversion of energy, and for the processing of materials, which have their own potential source of ignition and may cause an explosion. it also offers reliable protection from vacuum and overpressure Overpressure Overpressure refers to an increase in pressure in a system or vessel above the normal operating pressure. . It prevents intake of air and unacceptable product Product Includes equipment, protective systems, devices, components and combinations of these. vapor loss up to and until the set-to-operate pressure is reached. The valve can be used as an inbreathing device as well. In such an application, the main valve is directly controlled when exposed to a vacuum, i.e. it functions as a weight-loaded diaphragm valve.

As the working pressure rises, the closing force acting on the main valve increases, i.e. the valve's tight-sealing is enhanced until the set-to-operate pressure is reached, thus preventing leakage. Once the valve has commenced to lift Lift Lift is the actual travel of the valve pallet from the main valve out of the closed position. it opens fully within a 10% pressure rise or the opening pressure difference and the nominal volumetric fl ow is discharged through a fully open valve. If and when this level is exceeded the pressure increase will follow the performance curve (Δp/V.curve). From set pressure Set pressure Set pressure is the gauge pressure at the device inlet at which the relief device is set to start opening under service conditions. to full capacity (fully open valve) the pressure increase is 100% in case of vacuum venting/inbreathing function.