Check valve, a one-way flow control device, prevents reverse flow in pipelines. Widely used in water systems, oil/gas, and chemical industries. Composed of a valve body, disc (swing/lift type), spring, seat, and optional hinge or lift mechanism. Durable materials ensure corrosion resistance. Automatically opens under forward flow pressure and closes upon flow cessation. Features quick response to prevent backflow, minimize water hammer, and enhance system safety. Ideal for HVAC, water treatment, and industrial fluid control.