Ventilation improves the air environment of the workshop. On the one hand, the polluted air which does not meet the hygienic standards is discharged outdoors in some places or the whole workshop. On the other hand, fresh air or purified air which meets the hygienic requirements is sent into the room. We call the former exhaust and the latter intake.
If ventilation or supply is only carried out at local locations, that is, local ventilation; if ventilation or supply is carried out throughout the workshop, it is full ventilation. Generally, ventilation can be divided into local ventilation, comprehensive ventilation and accident ventilation according to the different scope of action of the ventilation system. Local ventilation system can be divided into local air intake and local air exhaust. Both of them make use of local air flow to protect local working places from harmful pollutants and create a good air environment.
(1) Local exhaust
In local places where harmful substances are concentrated, ventilation pipes in Shandong Province set up traps to remove harmful substances to control the indoor diffusion of harmful substances. This ventilation method is called local exhaust. This is the most effective ventilation method for anti-virus and dust removal.
Shandong Ventilation Pipeline
The local exhaust system consists of the following parts:
(1) Local exhaust hood
Local exhaust hood is used to trap harmful substances. Its performance has a direct impact on the technical and economic indicators of the local exhaust system. Local exhaust hood with good performance, such as airtight hood, can achieve good working effect as long as the air volume is small. Due to the difference of production equipment and operation, the forms of exhaust hood are various.
(2) Air duct
The pipeline that conveys gas in the ventilation system is called the air duct. It connects all kinds of equipment or components in the system into a whole. In order to improve the economy of the system, the gas velocity in the air duct should be selected reasonably, and the pipeline should be short and straight. Air ducts are usually made of smooth surface materials, such as thin steel plate, PVC board, and sometimes concrete, brick and other materials.
(3) Dust removal and purification equipment
In order to prevent air pollution, when the amount of harmful substances in the discharged air exceeds the discharge standard, it must be treated with purification equipment, after meeting the discharge standard, discharging into the atmosphere. The purification equipment can be divided into two categories: dust collector and harmful gas purification device.
The fan captures the power of air flow from the mechanical exhaust system. In order to prevent the wear and corrosion of the fan, it is usually placed behind the purification equipment.