What is shotcrete machine

1 What is shotcrete machine

A shotcrete machine is a small concrete pump equipment, which spray concrete mixture onto the construction surface. The shotcrete machine mainly consists of compressed air system, spray system, pumping delivery system, and control system.

 

Compressed air system

The compressed air system is the core part of the concrete shotcrete spraying machine, which is mainly composed of a compressor, air tank, pressure gauge, etc. 

Spraying system

The spraying system is the key part of the shotcrete spraying machine, which is mainly composed of gunite gun, shotcrete nozzle, shotcrete hose, rotating disk, guide plate, etc. 

Pumping delivery system

The pumping delivery system is an important part of the concrete spraying machine, which is mainly composed of concrete hopper, delivery cylinder, concrete piston, wear plate etc. 

Control system

The control system is an important part of the shotcrete spraying machine, which is mainly composed of electrical control box, buttons, switches, etc.

2 Shotcrete machine brand

Well-known brands such as Putzmeister, turbosol, zoomlion, jiuhe, xcmg, reed, CIFA, sany, sika, liebherr, schwing, normet in global.


These brands have taken the leading position in the market, and their influence and popularity are all over the world. In addition to shotcrete spray machine, their business scope covers construction machinery, concrete pump parts and accessories, concrete machinery, concrete pump, lifting machinery, compressors and other fields.


These brands represent the top level of the shotcrete machinery industry, not only excelling in performance, but also reaching extremely high standards in design and craftsmanship.


In today's engineering construction field, shotcrete machines are indispensable construction machinery, and their brand selection is crucial to the smooth progress of the project. When buying shotcrete spray machine, brand positioning is very important. Buying the right brand is basically half the battle.


They have been committed to product research and development and innovation to provide users with better quality shotcrete machine. High efficiency and energy saving, reliability and durability, and easy operation are also the direction they strive for.

3 Classification

3.1 Dry, wet and semi-wet shotcrete machine

According to the different methods of adding water to concrete mix, it can be divided into three types: dry, wet and semi-wet.


Dry shotcrete spray machine

After mixing cement and aggregate in proportion, they are evenly mixed and blown to the nozzle by compressed air, mixed with the pressure water from the pressure water tank and then sprayed out. This method is simple in construction and fast in speed.


Wet shotcrete spray machine

The concrete mixture that enters the spraying machine is already watered. Therefore, the dust content in the spraying is low and the rebound is also reduced, which is an ideal spraying method. However, wet materials are easy to condense in the material tank and pipeline, causing blockage and cleaning troubles.


Semi-wet shotcrete spray machine

Semi-wet type. Also known as wet type, the concrete mixture is a wet material with a moisture content of 5% to 8%. This material reduces dust when sprayed. Because it has less adhesion than wet materials and does not stick to the tank.

3.2 Trailer, truck mounted shotcrete machine


Trailer shotcrete machine are suitable for medium and short distance transportation. Truck mounted shotcrete machines are suitable for long distance transportation and require high-power engines.


Truck mounted shotcrete machine

A truck-mounted shotcrete machine is a concrete conveying device that installs a moved device on a truck chassis. It has both the mobility of a truck chassis and the function of concrete shotcrete spray. 


The truck mounted shotcrete machine has a wide range of applications and can be widely used in large-scale construction projects and water conservancy projects. Good construction quality, ensuring the uniformity and consistency of concrete, and ensuring the accuracy and density of concrete pouring positioning


Trailer shotcrete machine

Trailer shotcrete pump is a mobile concrete spraying machine, which consists of a conveying system, a hydraulic system, a lubrication system, etc. Trailer pump is suitable for medium and short distance concrete spraying.

3.3 Tank, spiral and rotor shotcrete machine


Tank shotcrete machine

The tank shotcrete machine is strong and durable. However, the machine body is too heavy, and the opening and closing of the upper and lower bell valves require heavy manual operations, which is labor-intensive and easy to cause pipe blockage.


Spiral shotcrete machine 

The spiral shotcrete machine has a simple structure, small size and good maneuverability. However, when the conveying distance exceeds 30 m, it is easy to backflow, and the productivity is low and unstable. It is suitable for small tunnels shotcrete spraying.


Rotor shotcrete machine

The rotor spraying shotcrete machine has the advantages of large production capacity, long conveying distance, continuous and stable discharging, low loading height, easy operation, and suitability for mechanized supporting operations. It can be used for various spraying methods such as dry spraying, semi-wet spraying and wet spraying.

4 Shotcrete machine spare parts

Shotcrete machine spare parts included but not limited: shotcrete hose, shotcrete clamp, shotcrete nozzle assembly, shotcrete seal kits etc.


4.1 Shotcrete rubber hose

Shotcrete hose is a tube for applying at wet machine equipment. The shotcrete hose is spray mortar, plaster by connect with gunite nozzle. The shotcrete hose bears high pressure, which effectively reduces the plug rate and enhances the injection performance.


4.2 Shotcrete clamp

Shotcrete clamp is a connection device, which is using for fix concrete pipe and shotcrete hoses. The concrete clamps play an important role in the pipeline system, shotcrete clamp has the advantages of simple structure, easy use, firm and durable.


4.3 Shotcrete gunite nozzle assembly

Shotcrete nozzle assembly is including chamber body, air compressor connector, polyurethane nozzle tips, concrete hose clamp etc. Shotcrete nozzle is applying for concrete spray in engineering civil. The gunite gun is the part that sprays the concrete mixture onto the construction surface, and the nozzle tip is used to adjust the flow and shape of the spray.

5 Shotcrete machine advantages 

Shotcrete machine is a special equipment for spraying concrete, which is often used in large-scale construction such as tunnels and water conservancy projects. It has the advantages of fast spraying speed, high construction speed and good construction quality.


High pumping pressure: hydraulic pumping, stable performance, strong reliability, and adaptable to difficult construction environments.


Simple operation: The construction method is simple, the transportation distance is long, and labor is saved.


High strength: Shotcrete is dense, homogeneous and high in strength. Shotcrete is sprayed at high speed, so that the aggregate and cement are compacted by continuous impact, thus having higher strength. 

Anti penetrate: Sprayed concrete has fewer voids, less water-cement, and better anti-penetation properties.


Environmentally friendly: No formwork is required, saving wood and steel. 

Wide range of applications: Shotcrete machine widely used in underground engineering, geotechnical engineering, municipal engineering, water conservancy engineering, civil engineering.

6 Shotcrete machine application


Concrete shotcrete machine is a kind of construction equipment, Shotcrete machine has high working efficiency, low rebound, high degree of concrete hydration, and can greatly improve the quality of shotcrete and improve the homogeneity of concrete etc.


Shotcrete machine is widely used in mines, tunnels, rock slopes, building foundation pits, building structure reinforcement and other projects. It is widely used in the lining construction of tunnels, culverts and other projects.


Spray machine can be used to repair aged or damaged building structures. By spraying concrete onto cracks or damaged structures, the shotcrete machine can repair and enhance their bearing capacity. 


Wet shotcrete can be sprayed directly onto the rock surface to form a solid tunnel wall, improving the stability and safety of the tunnel.


Shotcrete machines spray concrete into formwork to quickly create building structures of various shapes and sizes.

7 Selection principles


Whether the selection of shotcrete spraying machine is reasonable directly affects the construction progress and project quality. Therefore, the type and quantity of shotcrete machine should be correctly selected according to the size of the project, the length of the construction period, the specific construction conditions, etc. The specific selection should be carried out according to the following principles:


It is suitable for the size of the project and the length of the construction period. If the amount of concrete is not large and the construction period is not too long, a small mobile concrete mixer can be selected. If the amount of concrete is large and the construction period is long, a medium or large concrete spraying machine group should be selected.


If the conveying distance is far and the working wind pressure is low, dry spraying is suitable. When the spraying working surface has water seepage or a wet base surface, a dry spraying machine should be used.


For large-section tunnels and large caverns, the wet-mix spraying method should be used for shotcrete support. For foundation pits and slopes, the dry-mix spraying method should be used for shotcrete support.

8 Maintenance

 Since the shotcrete machine is often used in harsh construction environments, it is very easy to malfunction, so it must be carefully maintained. In order to better protect the shotcrete spraying machine, reduce the failure rate and reduce the maintenance cost, it is recommended that operators develop a maintenance record sheet for the shotcrete spraying machine. The record sheet should include the following contents: 


Daily maintenance records: including cleaning, checking lubricating oil, checking electrical appliances, cleaning filters and other daily maintenance records.


Maintenance records: including maintenance items, maintenance date, maintenance personnel and maintenance status, etc.


Fault record: including fault time, fault cause, fault repair and inspection status, etc.


By establishing a maintenance record sheet for shotcrete spraying machines, users can timely understand the maintenance and fault conditions of machines, and perform maintenance on the machines and repair faults according to the record sheet. At the same time, the record sheet is also conducive to the management personnel to formulate maintenance plans for shotcrete spraying machines and improve the efficiency and service life of the machines.