What is a shotcrete pump？A shotcrete pump, also known as a concrete spraying machine, is a device used to spray concrete or mortar onto a surface at high velocity. This process is commonly used in construction and tunneling projects to create a durable and protective layer of concrete.

　　How does a shotcrete pump work?

　　Here's how it works:

　　1. Mixing the Concrete: The process begins with the mixing of the concrete or mortar. This is typically done in a mixer or batching plant, where the dry ingredients (cement, sand, and aggregate) are combined with water to form a wet concrete mix.

　　2. Feeding the Pump: The wet concrete mix is then fed into the shotcrete pump. The pump is designed to handle the thick and abrasive nature of the concrete mix.

　　3. Pressurizing the Mix: The pump uses a piston or a rotor-stator mechanism to pressurize the concrete mix. This pressurization is what allows the concrete to be sprayed at high velocity.

　　4. Spraying the Concrete: The pressurized concrete mix is then forced through a hose and out of a nozzle. The nozzle is designed to atomize the concrete mix, breaking it into small droplets that can be easily sprayed onto the surface.

　　5. Accelerating the Setting: In some cases, an accelerator may be added to the concrete mix just before spraying. This helps the concrete to set more quickly, which is especially useful in tunneling applications where rapid support is needed.

　　6. Applying the Concrete: The sprayed concrete is then applied to the surface in a controlled manner. The operator of the shotcrete pump can adjust the spray pattern and velocity to ensure an even application.

　　7. Curing the Concrete: After the concrete has been sprayed, it needs to be cured to reach its full strength. This typically involves keeping the concrete moist for a period of time, which can be achieved through the use of curing compounds or by covering the sprayed surface with plastic sheeting.

　　Types of Shotcrete Pumps

　　There are two main types of shotcrete pumps:

　　1. Dry-Mix Shotcrete Pumps: These pumps are used with a dry concrete mix. The water is added at the nozzle, which helps to control the amount of water in the mix and can improve the quality of the sprayed concrete.

　　2. Wet-Mix Shotcrete Pumps: These pumps are used with a pre-mixed wet concrete. The advantage of wet-mix shotcrete is that it can provide a more consistent mix and better quality control.

　　Features of a Shotcrete Pump

　　- Pump Pressure: Determines how far and at what speed the material can be applied.

　　- Hose Length: Affects the reach of the application.

　　- Output Capacity: Defines how much material the pump can handle per hour.

　　- Portability: Varies from small, portable units to large, trailer-mounted machines.

　　Shotcrete pumps are used in a variety of applications, including:

　　- Tunnel construction

　　- Mine shaft lining

　　- Slope stabilization

　　- Swimming pool construction

　　- Architectural concrete finishes

　　 A shotcrete pump is used to spray concrete (shotcrete) onto surfaces at high velocity, often for construction projects like tunnel linings, swimming pools, or slope stabilization.