Basic Introduction of Sandblasting Room

Sandblasting is the most common method for dedusting of medium thick plates, and acid pickling is no longer adopted. Sandblasting has the advantages of high productivity and low cost, which can improve the ambient environmental hygiene conditions, reduce the labor intensity,present uniform roughness on the plate surface after sandblasting, increase the surface area, increase the adhesion of the paint, prolong the use time of the paint, and enhance the protective effect of the film.

Sandblasting machine is divided into horizontal type and vertical type sandblasting machine. The steel plate of horizontal type sandblasting machine is placed horizontally, while that of vertical type sandblasting machine is placed vertically, and usually the both sides are sandblasted at the same time. The steel plate transportation of horizontal type sandblasting machine is more convenient, the production capacity is large and the application is wide, but it occupies a large area and the equipment is heavy. Vertical type sandblasting machine needs double vertical plate machine, and it is not suitable for wide sheet plates because it is easy to fall after standing up, while it only occupies a small area, does not need to remove the falling shots, and is light. Now it is rarely used because of its low processing capacity and narrow sandblasting room and difficult maintenance.

The horizontal type sandblasting room is equipped with 2-8 impeller ramming heads on the top and bottom of the steel plate. Each head is driven by the motor, which can make the impeller rotate at a high speed and impact steel or iron shots onto the derusting steel plate with a rotating centrifugal force of about 80 m/s. The oxide skin and rust on the plate surface will be removed by the impact of the shot and the friction with the steel plate.

The sandblasting machine booth is usually composed of conveying roller, sandblasting machine, sandblasting room, sandblasting recycling system, sandblasting blowoff device and dust collecting device, and so on. The wear resistance requirements of the roller under the ramming head should be considered; the inlet and outlet of the sandblasting booth should be sealed with the curtain to prevent the dust from spreading and affecting the working environment; the iron sheet residue should be blown off by the airbrush after being sandblasted; the shots should be collected and lifted into the distributor for reuse after filtration, and the dust and ash should be discharged and collected by the deduster. The consumed sand should be replenished regularly.

The cleaning degree of sandblasting should reach 100%. If not, it should be cleaned for the second time or be removed manually.

The surface roughness of the sandblasted plate should be less than 50 μm based on the calculation of hitting depth. The quality of the cleaning degree and roughness depends on the sandblasting speed. If the speed is high, the impact kinetic energy will be high, the cleaning effect will be good and the roughness will be high. The second is the size of the sandblasting particles. The finer the particles, the more the number of balls thrown per unit time, the greater the number of impacts, and the higher the density of pitting, so the degree of removal is higher. However, the larger the particles, the larger the roughness, the larger the number of sandblasting, the larger the flow, and the better the removal. In addition, the longer the ejection lasts, the higher the clearance, but it has little effect on the roughness.