The PS2I-D rotor concrete spraying machine has the characteristics of advanced technology, reasonable structure, stable performance, convenient operation and maintenance, and long service life. It is a micro-spraying machine specially designed for refractory materials and new thin spraying materials. It is widely used in the spraying construction of tunnels, culverts, subways, hydropower projects, underground projects and coal mines.

1. Machine structure and working principle
The structure of the PS2I-D rotor concrete spraying machine is shown in Figure 1. The mixed material is sent into the spraying machine hopper from the discharge port of the batching mixer (or manual mixing and feeding), injected into the T-shaped inner cavity of the rotor, and swirls with the rotor to the discharge port. Here, compressed air is introduced from the air chamber to blow the material into the discharge elbow, blow the material away, accelerate it, and make it float, enter the feed pipe, reach the nozzle, and then add a small amount of water to spray it out.
2. Machine structure
PS2I-D rotor concrete spraying machine is mainly composed of drive device, rotor assembly, air circuit system, injection system, electrical system and other parts.
The machine adopts a unique T-shaped rotor cavity, which improves the machine's ability to handle materials and reduces the workload of cleaning and maintenance. Made of high-grade alloy tool steel, the overall quenching hardness is HRC48-54, and the service life is long.
Joint plate: There are two upper and lower pieces, which are made of special rubber pressed on the skeleton plate, with good wear resistance and excellent sealing effect. The air circuit system is divided into two routes:
One of the air routes is supplied to the rotor assembly hopper seat through the air distributor to ensure its working air pressure and air volume; so that the material can be smoothly transported and sprayed to the sprayed surface.
The other air route is connected to the hopper vibrator through the air distributor to facilitate vibration unloading. The two ball valves in the pipeline are used to control the upper air route of the spraying and the hopper vibrator. A pressure gauge is installed on the air distributor to monitor the pressure of the external air source and the working air pressure of the conveying pipe.
The injection system consists of a feed hose and a nozzle.