This swing check valve is manufactured in accordance with API 594 and ASME B16.34 American industrial standards. The valve body is integrally cast with WCB carbon steel, adopting bolted bonnet swing disc structure. Driven by fluid flow pressure and gravity, the swing disc opens automatically for medium forward flow and closes tightly to block reverse flow, which effectively protects pipeline pumps, instruments and other equipment from backflow impact damage. The metal hard sealing surface achieves reliable zero leakage under high-pressure working conditions.