Shotblasting installation: operating principle

The mechanical action of fine-grained abrasives has long proved its effectiveness in the processing of various surfaces. Even a small pneumatic gun allows cleaning of complex traces of corrosion damage, scale and consequences of chemical burns. However, in conditions of large-scale construction or industrial production of capacities and coverage of hand sandblasters may not be enough. In such situations, a shot blasting machine is used, which can act on the same principle of abrasive feed, but with different operating parameters.

What is a shot blasting?

To understand the purpose and features of such units, it is worth considering the principle of the action of abrasive blasting machines as such. Through a special nozzle, small guns deliver sand to the working surface, which, when collided with the material being processed, ensures its cleaning. The abrasive force can be provided by different methods. The most common supply of compressed air, which provides a compressor installation. Less popular is the direction of the water jet, 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 unit is used, acting on the principle of mechanical feeding of abrasives with special blades. The specific features of aggregates of this type include the use of metallic particles as an active purification component.

General device of shot blasting aggregates

Virtually any shot blasting machine contains a working wheel provided with blades supplying 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-alloyed cast iron, which has an increased resistance to abrasion. In addition, the shot blasting unit is equipped with strong bearings, the material of which is also designed for operation under conditions of intense mechanical impact. The fact is that the wheel and the working units adjacent to it directly interact with working abrasives made of metal. The work is carried out at high speed, so the loads on the materials are considerable. In this case, the wheel is 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.

Main characteristics of the equipment

The quality of cleaning, as in the case of hand sandblasters, is determined by the capacity of the unit. But if the performance of a conventional pneumatic device depends on the function of the compressor, the performance of the fractions is determined by the power of the electric motor that drives the wheel with the blades. The power potential of the motor is on the average 10-15 kW. Such power, for example, has a shot blasting unit for cleaning sheet metal and construction metal structures, available for placement in the chamber. Thus, 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 the loaded parts - as a rule, the maximum weight reaches 1 ton. With regard to the performance of the plant itself, it reaches an index of 100-150 kg / min. In this case, one camera can serve several devices at once.

Principle of operation of suspended installations

These are units with tunnels in which the blanks are cleaned. Suspended principle of operation is effective due to the fact that operations can be carried out from different sides. The construction fixing the product is a special conveyor, which moves in the tunnel. The operator can use shot-blasting installations of a hanging type on the principle of flow, that is, perform serial processing of parts. True, the possibility of such exploitation depends on the system for collecting discarded metal particles - abrasives. The fact is that the classical shot blasting machine is designed for a one-time operation.

At least after processing one element requires a small amount of time to perform the collection of hardware. Moreover, time takes also the process of separating the abrasive mass from the impurities that were discarded as a result of the supply of the active material. Sometimes automatic work is also envisaged for shot blasting plants, in which a continuous process of collecting, cleaning and ejecting metal products takes place.

The principle of running models

This is the basic model, which is part of the group of continuous operations. Its functional basis is made up of a metal mesh conveyor, which moves the billet into the cleaning chamber. The process is carried out in a closed working chamber, which can be provided with a different number of turbines. The merits of a shot blasting machine of the through-type type include the ability to provide thorough and even processing of parts. Most importantly, the workflow does not require the element to be turned over. Due to the blind system, as well as the blowdown mechanisms, it is possible to count on a high quality of cleaning. Passing aggregates are now actively used for machining parts in machine building, for cleaning building metal sheets, in the manufacture of aluminum alloys, and so on.

Principle of operation of drum drobets

This is a fairly practical unit, which is most often used in the metallurgical industry for the final processing of the resulting alloys. For example, such a system can rid the surface of traces of molding solutions, scales and fumes. Moreover, provided that a suitable abrasive is selected, it is possible to provide a surface roughness with the desired characteristics. So, in the working process, two main components are involved: a hydraulic hoist, which falls asleep work pieces, and the drum itself, where the cleaning takes place. In the course of the operation, a container made of perforated metal tape rotates, allowing the products to be processed from different sides. Accordingly, the shot blasting unit of the tympanic type also makes it possible to obtain at the exit qualitatively purified articles. The operator can carry out the movement of the drum turbine manually or by means of special control panels. However, the control system should be considered separately.

Equipment management system

The latest versions of such equipment provide for the use of special controllers based on a programmable module. This means that the user can pre-set operating parameters for the operation of the mechanisms. The main indicators that can be controlled in this way are: the feed rate, the intensity of movement inside the working chamber, and the interval of finding one workpiece in the vehicle. The way the operator interacts with the controller depends on the design of the shot blasting machine itself. The principle of operation can provide for small dimensions, which allow to equip the control station with the main structure. If the equipment is included in a common production line, the control room in the form of a cabinet can be located at a considerable distance from the place of operation.

What to consider in the choice of installation?

To pay attention to the choice of shotmaker follows several parameters. First of all, the capacity and design of the equipment is determined. It is important to understand with what materials the unit will work - it can be both sheet metal, and wire, as well as small parts that require delicate cleaning. With regard to the design, it can assume integration in the production complex or act as a separate technological area. For example, shot blasting passages are suitable for serial machining of parts of different sizes, so it is advisable to use them in large production environments. Also it is necessary to take into account the availability of additional functions, among which automatic assembling of the released abrasive and cleaning of the parts during processing.

Conclusion

Typical for many auto mechanics and painters, sandblasting machines in the quality of processing in some versions correspond to the shot blasting. The main difference from the point of view of the characteristics of the result obtained is reduced to the coverage area. That is, the quality of processing can be equal, but in one session the shot blasting unit will service several times more parts than traditional pneumatic devices. This is the reason for the prevalence of abrasive blasting equipment of this kind in industry and large construction projects. In the small-scale format of cleaning, the use of such equipment is inappropriate, primarily for energy efficiency reasons.