Safety valve should be set maintenance platform. To consider the layout of the safety valve after a large weight lifting may dismantle the safety valve, Baoji mixer repair, if necessary set up boom. Valve inlet pipe should be long radius elbows. Design of safety valve outlet pipe backpressure shall not exceed a certain value considering the constant pressure of the safety valve. For ordinary spring safety valve, mixer maintenance organizations, which does not exceed 10% of the back pressure valve constant pressure value. Compared with purely mechanical and hydraulic transmission, hydraulic transmission main advantage is the flexibility of its ease of adjustment and layout, can be the shape and construction machinery working conditions, the engine, wheel, work organization and other parts are arranged in a reasonable position, engine speed in either a work scheduling, mixer maintenance unit, the transmission system can play a greater traction, and transmission over a wide range of output speed to maintain a higher efficiency, and can easily obtain a power transmission characteristics of various optimized to suit the load status of various jobs.