This paper introduced the working principle of electric curved valve, double curved electric-hammer valve and pneumatic-hammer flap valve. The weakness of these traditional valves has been analyzed in practical production. Base on the above research, we developed a new type of double-layer pneumatic gate valve. The double-layer pneumatic gate valve is composed of two upper and lower body and "middle box". It has the characteristics of flexible switch and good airlock effect. The valve is provided with an "escape" mechanism to prevent the clinker powder from blocking the valve plate. The opening and closing time of the gate can be adjusted by the PLC controller, and so the automatic control function of "automation, zero failure, zero leakage and maintenance-free" is realized.