wherein the pressure intensifier comprises an electromagnetic valve seat, a pressurizing chamber, and a discharge flow pup joint fixedly connected in sequence along an axial direction;

an electromagnetic valve is arranged in the electromagnetic valve seat, and the electromagnetic valve is a two-position three-way electromagnetic valve; the electromagnetic valve seat is provided with a through electromagnetic valve seat flow channel, the electromagnetic valve seat flow channel is connected to a port P of the electromagnetic valve, a port A of the electromagnetic valve is connected to a pressurizing chamber inlet flow channel arranged in the electromagnetic valve seat, a port T of the electromagnetic valve is in communication with an annular space between a drill rod and a casing pipe;

a plunger is coaxially arranged in the pressurizing chamber, an upper end of the plunger is in sealed slide fitting with an inner wall of the pressurizing chamber, the plunger is in sealed slide fitting with a lower end of the pressurizing chamber; the upper end of the plunger separates the inner chamber of the pressurizing chamber into a non-rod chamber and a rod chamber; a first flow channel of the pressurizing chamber and a second flow channel of the pressurizing chamber are arranged on a cylinder wall of the pressurizing chamber; a one-way valve is arranged between the first flow channel of the pressurizing chamber and the rod chamber, a flow direction of the one-way valve is from the first flow channel of the pressurizing chamber to the rod chamber; the rod chamber is in communication with the second flow channel of the pressurizing chamber;

a conveying pipe is arranged inside the discharge flow pup joint, a flow channel is formed between an outer wall of the conveying pipe and an inner wall of the discharge flow pup joint;

the drill bit is connected to the discharge flow pup joint;

the electromagnetic valve seat flow channel, the first flow channel of the pressurizing chamber, the flow channel, and the bit water way are sequentially in communication with each other; the pressurizing chamber inlet flow channel is in communication with the non-rod chamber, the second flow channel of the pressurizing chamber, the conveying pipe, and the inner chamber of the drill bit are sequentially connected to each other; a high pressure valve is arranged between the second flow channel of the pressurizing chamber and the conveying pipe;

the electromagnetic valve seat comprises an electromagnetic valve upper seat and an electromagnetic valve lower seat which are fixedly connected;

the electromagnetic valve seat flow channel passes through the electromagnetic valve upper seat and the electromagnetic valve lower seat;

the pressurizing chamber comprises an upper plunger cylinder and a lower plunger cylinder which are fixedly connected, and the upper plunger cylinder is fixedly connected to the electromagnetic valve lower seat;

the first flow channel of the pressurizing chamber passes through the upper plunger cylinder and the lower plunger cylinder;

the upper end of the plunger is in sealed slide fitting with an inner wall surface of the upper plunger cylinder, the plunger is in sealed slide fitting with an inner wall surface of the lower plunger cylinder;

the second flow channel of the pressurizing chamber is arranged on the lower plunger cylinder;

the pressure valve comprises a valve body coaxially arranged at a lower end of the lower plunger cylinder, the valve body is provided with a valve body channel in communication with the conveying pipe;

an inner upper part of the valve body is fixedly provided with a sealing head, an inner lower part of the valve body is slidably fitted with a conical valve core; a lower part of the conical valve core is sleeved with a reset spring, and a lower end of the reset spring is pressed against support step on an inner side of the valve body;

a bottom of the sealing head is a conical structure with a narrow top and a wide bottom, a bottom conical surface of the sealing head and an upper conical surface of the conical valve core form a conical sealing structure under an action of the reset spring;

an inner cavity of the sealing head is in communication with the second flow channel of the pressurizing chamber; and

after the conical valve core is moved downwards, the inner cavity of the sealing head is in communication with the valve body channel.