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Water system pressure regulating valve is suitable for clean water, hot and cold circulating water and industrial water, widely used in building water supply and drainage, HVAC and fire fighting system. It is suitable for normal to medium temperature working conditions, and the working temperature is generally from 0℃ to 80℃. The valve stabilizes the system pressure by automatically adjusting the valve opening to prevent pressure fluctuations from damaging the equipment and pipe network. The valve body material usually adopts ductile cast iron, stainless steel or copper alloy, and the seals are made of wear-resistant rubber or polyurethane, which ensures corrosion resistance, good sealing, adapts to a variety of complex working conditions, reliable operation and easy maintenance.