The mechanical action of fine-grained abrasives has long been proven to be effective in treating various surfaces. Even a small-sized pneumatic gun allows you to clean complex traces of corrosion damage, scale and the effects of chemical burns. However, in conditions of large-scale construction or industrial production of capacities and the coverage of manual sandblasting machines may not be enough. In such situations, a shot blasting machine is used, which can operate according to the same principle of feeding abrasives, but with different operating parameters.
What is a shot thrower?
To understand the purpose and features of such units, it is worth considering the principle of operation of abrasive blasting machines as such. Through a special nozzle, small guns feed sand onto the working surface, which, in a collision with the material being processed, ensures its cleaning. The force for feeding the abrasive can be provided by different methods. The most common supply of compressed air, which provides a compressor unit. Less popular is the direction of the water stream, which contains the same particles of sand. However, to work with large volumes, both technologies are not suitable. In solving such problems, a shot blasting machine is used, operating on the principle of mechanical feeding of abrasive with special blades. The features of units of this type include the use of metal particles as an active component of purification.
The general structure of shot blasting units
Almost any shot blasting machine contains an impeller based on the blades that feed the abrasive. This is the main functional component, which is also subjected to the greatest physical stress. Therefore, the blades and wheel base are made of high-alloy cast iron, which has increased resistance to abrasion. In addition, the shot blasting machine is equipped with durable bearings, the material of which is also designed for operation in conditions of intense mechanical stress. The fact is that the wheel and the working units adjacent to it directly interact with metal working abrasives. The work is performed at high speed, therefore, the load on the materials is considerable. In this case, the wheel is located in a special chamber made on the basis of a steel alloy. The target object is placed in this camera, after which the processing process is started.
Key Features
The quality of cleaning, as in the case with manual sandblasting, is determined by the power of the unit. But if in the operation of conventional pneumatic devices the performance depends on the function of the compressor, then the operation of the shot blades is determined by the power of the electric motor, which drives the wheel with blades. The power potential of the motor averages 10-15 kW. Such a power, for example, has a shot blasting machine for cleaning sheet metal and building metal structures available for placement in the chamber. So, the average parameters of products available for cleaning in such equipment are about 700 x 700 x 1200 mm. There are also restrictions on the mass of loaded parts - as a rule, the maximum weight reaches 1 t. As for the productivity of the installation itself, it reaches 100-150 kg / min. At the same time, several cameras can serve one camera at once.
The principle of operation of suspended installations
These are aggregates with tunnels in which the workpieces are cleaned. The suspended principle of action is effective due to the fact that work operations can be carried out from different sides. The design fixing the product is a special conveyor, which moves in the tunnel. The operator can use suspended shot blasting machines according to the principle of flow, that is, perform serial processing of parts. True, the possibility of such operation depends on the collection system of discarded metal particles - abrasives. The fact is that the classic shot blasting machine is designed for a one-time operation.
At least after processing one element, a short period of time is required to complete the collection of hardware. Moreover, the process of separating the abrasive mass from contaminants that were discarded as a result of the supply of active material also takes time. Sometimes automatic work is also provided for in shot blasting plants, in which there is a continuous process of collecting, cleaning and ejecting hardware.
The principle of operation of passing models
This is the basic model that is part of the continuous shot blast group. Its functional basis is a metal mesh conveyor, which moves the workpiece inside the cleaning chamber. The process is carried out in a closed working chamber, which can be provided with a different number of turbines. The advantages that a shot-through type shot blasting machine possesses include the ability to ensure thorough and uniform processing of parts. Most importantly, the workflow does not require the element to be turned over. Thanks to the blinds system, as well as the blowing mechanisms, you can count on high quality cleaning. Feed-through units today are actively used for machining parts in machine-building production, in the cleaning of building metal sheets, in the manufacture of aluminum alloys, etc.
Principle of Operation of Drum Shotguns
This is a fairly practical unit, which is most often used in the metallurgical industry for the final processing of the obtained alloys. For example, such a system can save surfaces from traces of molding solutions, scale and burns. Moreover, provided that a suitable abrasive is selected, a surface roughness with the desired characteristics can be ensured. So, in the workflow, two main components are involved: a hydraulic lift, which falls asleep the workpiece, and directly the drum, where the cleaning takes place. During the operation, the container made of perforated metal tape rotates, allowing you to process products from different sides. Accordingly, the drum-type shot blasting machine also makes it possible to obtain high-quality cleaned products at the output. In this case, the operator can carry out the movement of the drum turbine manually or through special control panels. However, control systems should be considered separately.
Equipment management system
The latest versions of such equipment include the use of special controllers based on a programmable module. This means that the user can pre-set the operating parameters of the operation of the mechanisms. The main indicators that can be controlled in this way include: feed rate, the intensity of movement inside the working chamber, as well as the interval of finding one workpiece in the vehicle. The way the operator interacts with the controller depends on the design in which the shot blasting machine itself is made. The principle of operation may include small dimensions, allowing to equip the main structure with a control point. If the equipment is part of a common production line, then the control point in the form of a cabinet can be located at a considerable distance from the place of operation.
What to consider when choosing an installation?
When choosing a shot thrower, one should pay attention to several parameters. First of all, the power and design of the equipment are determined. It is important to understand what materials the unit will work with - it can be sheet metal, wire, as well as small parts that require delicate cleaning. As for the design, it may involve integration into the production complex or act as a separate technological section. For example, shot blasting plants are suitable for serial processing of parts of different sizes, so it is advisable to use them in large-scale production. It is also worth considering the presence of additional functions, including automatic assembly of the released abrasive and cleaning of parts during processing.
Conclusion
Sandblasting machines, which are usual for many car mechanics and painters, correspond to shot blasters in terms of the quality of processing. The main difference in terms of the characteristics of the result is reduced to the coverage area. That is, the quality of processing can be equal, but in one session, the shot blasting machine will service several times more details than traditional pneumatic devices. This determines the prevalence of abrasive blasting equipment of this kind in industry and large construction projects. In a small-scale format for cleaning, the use of such equipment is impractical, primarily for reasons of energy efficiency.