Single-valve-seat sand-prevention large-drift-diameter high-pressure gate valve

The invention discloses a single-valve-seat sand prevention type large-drift-diameter high-pressure gate valve which comprises a valve body and an executing mechanism. Wherein a valve seat is arranged in a valve cavity of the valve body; a sand baffle is arranged on the valve seat and close to the end part of the gate plate; sealing pieces matched with the valve seat holes of the valve body are respectively arranged on the peripheral wall and the end face of the valve seat; a wave spring is further arranged between the rear end face of the valve seat and the inner wall of the valve cavity. The single-valve-seat structural design is adopted, the wave spring is installed on the rear end face of the valve seat, so that the valve seat and the gate plate can be attached more tightly, a steel-to-steel structure sealing mode is formed, and fracturing sand is prevented from entering a valve body cavity when the valve is opened under pressure; and invasion of fracturing sand under the pressure environment can be more