In the shot blasting process of the shot blasting machine, the steel shot is projectile with a high speed, it will collide and friction with the workpiece. After passing through the recovery system, dust will be generated. The dust collector is to remove the dust in the blasting chamber and other devices to prevent air pollution.
The dust collector can be divided into three levels: coarse purification, medium purification, and fine purification according to the size of the collected dust particles. Coarse purification is to capture dust particles larger than 100 microns, medium purification is to capture dust particles of 10-100 microns, and fine purification is to capture dust particles of 10 microns. Increasing the number of dust removal stages in the ventilation and dust removal device can obviously improve the dust removal efficiency, but the general dust removal system only uses two-stage dust removal; only the one-stage fine-purification dust collector is used for the cleaning work with the least dust.
The function of the dust collector is basically the same as that of the volumetric separator, but the structure is simpler. Its main function is to make the airflow to settle down the coarse particles in the airflow when it flows down in a roundabout way, so as to reduce the burden of the dust collector used in the second and third levels of dust removal and purification. The settling box is used for coarse purification, the second level dust collector is used for intermediate purification, and the third level dust collector is used for fine purification. The second level of dust removal generally uses the CLT/A cyclone dust collector, and its dust removal efficiency can reach up to 70-90. When dealing with large air volume, a large-diameter cyclone dust collector is required, but the dust removal efficiency will be reduced at this time. In order to maintain high dust removal efficiency, a two-stage cyclone dust collector with a concentrator of model CR205 can be used to remove dust. The efficiency is 85-90. The third level dust collector generally adopts LDM type pulse jet type filter cartridge dust collector. When the dust on the filter cartridge is removed, this kind of dust collector can clean the dust without stopping the wind. Its dust removal efficiency is 90. There is also a flat bag cylindrical rotary back-blowing dust collector. Its single machine capacity is large, which can make the piping system simple and occupy a small area. It is especially suitable for large air volume and high negative pressure ventilation and dust removal devices. In addition, a wet CCJ/A self-excited dust collector can also be used, with a dust removal efficiency of 98-99.
Dry dust collector finally solves the problem of ash transportation and treatment; wet dust collector must solve the problems of sludge treatment and sewage treatment. In the northern region, it also solves the problem of antifreeze, and the sewage treatment device is relatively large.
In ventilation and dust removal devices, high-pressure centrifugal fans are usually used. The exhaust noise and mechanical noise produced by high-pressure centrifugal fans will cause harsh working environments. For this reason, a silencer can be installed on the exhaust spring of the fan. To reduce exhaust noise. In order to reduce the mechanical noise, the ventilator can be placed in the ventilator room with sound insulation device, or the sound insulation material can be hidden outside the ventilator casing.