The use of ventilation methods to improve the air environment of the workshop, on the one hand in the local site or the entire workshop does not meet the health standards of dirty air discharged to the outside, on the other hand, the fresh air or purified health requirements into the room. We call the former exhaust, the latter known as the wind.

In the centralized place to produce harmful substances, set the capture device, the excretion of harmful substances to control the spread of harmful substances to the indoor, this ventilation method known as the local exhaust. This is the most effective way to prevent air and dust.

The local exhaust system consists of the following parts:

(1) local exhaust hood

Partial hood is used to catch harmful substances. Its performance has a direct impact on the technical and economic indicators of the local exhaust system. Good local exhaust hood, such as a closed cover, as long as the smaller air volume can get a good work results. Due to the different production equipment and operation, the form of exhaust hood is varied.

(2) ducts

Ventilation system in the pipeline to call the gas duct, which the system of various equipment or components into a whole. In order to improve the economy of the system, the gas flow rate in the duct should be selected reasonably, and the pipeline should be short and straight. Ducts are usually made of smooth material, such as: thin steel plate, PVC board, sometimes with concrete, brick and other materials.

(3) dust removal, purification equipment

In order to prevent air pollution, when the discharge of harmful substances in the air exceeds the discharge standards, must be treated with purification equipment, to meet the emission standards, the people discharged into the atmosphere. Purification equipment, sub-dust and harmful gas purification device two categories.