A check valve, also known as a non-return valve, one-way valve, reflux valve, or isolation valve, is an automatic valve that relies on the pressure of the medium itself and the weight of the valve disc to automatically prevent backflow, belonging to the category of automatic valves. The movement of its valve disc is categorized into lift type, swing type, butterfly type, etc. Among these, the lift type resembles the structure of a globe valve but lacks a valve stem, while the swing type employs an inclined disc that rotates around a shaft. This valve is widely used in petrochemical industries, water supply and drainage systems, and as a bottom valve in pumping installations. It helps prevent water hammer effects and medium backflow. When combined with a globe valve, it can achieve safe isolation functionality.
