The square drill pipe plug valve is a manual control valve in the drill string circulation system and is one of the effective tools to prevent blowouts. The square drill pipe plug valve can be divided into upper square drill pipe plug valve and lower square drill pipe plug valve. The upper square drill pipe plug valve is used between the lower end of the faucet and the square drill pipe; The lower square drill pipe plug valve is used between the lower end of the square drill pipe and the protective joint of the square drill pipe. The drilling fluid can flow freely through the square drill pipe plug valve without pressure drop. Use a specialized wrench to rotate 90 ° according to the instructions to achieve the switch.

characteristic; The upper and lower plugs of the square drill pipe are composed of a body, a lower ball seat, a spring, an operating key, a ball valve, an opening retaining ring, an upper ball seat, a blocking ring, an elastic retaining ring, seals, and accessory wrenches. The sealing principle is that the ball seat is supported by a spring to position the ball and provide a certain degree of pre tension. The ball is in close contact with the sealing element of the ball seat. When released, the water hole is unobstructed, and when closed, the spherical surface completely seals the water hole. The pressure of the inner annular part acts on the ball, causing it to be in a high-pressure sealing state with the ball seat