PPH Single Union Swing Check valves are non-return valves. When the medium flows in the designated direction, the valve disc opens under the force of the medium; when the flow reverses, the valve disc and sealing surface close tightly due to the weight of the disc and reverse medium force. This prevents backflow. Made from high-grade materials with excellent impact resistance and stable chemical properties, these valves are commonly used in metallurgy, electronics, and other industries. In applications such as pickling tanks or electrolyzers, they help reduce maintenance and prolong equipment life, making them essential in the chemical industry.