P20/P20D is a kind of mechanical equipment that can be used for both shotcreting and grouting. The shotcrete uses the thrust generated by a hydraulic pump to make two oil cylinders alternately move back and forth to send dense flow materials from the conveying pipe to the mixed flow pipe. The compressed air forms a thin stream and is sent to the nozzle through the pipeline. A certain proportion of accelerator is added to the nozzle and sprayed directly onto the sprayed surface; grouting directly sends dense flow materials to the pouring body from the conveying pipe; widely used in houses Construction, highways, railways, tunnels, hydropower stations and other projects are under construction.