Views:0 Author:Shandong snyli Publish Time: 2020-07-04 Origin:Site
Folding wind speed control
The airflow in the clean shed is an important factor affecting the performance of the clean room. Generally, the airflow speed of the clean room is selected between 0.25~0.5m/s. This airflow speed belongs to the breeze area, which tends to be disturbed by the actions of people and machines. Chaos. Although increasing the wind speed can suppress the influence of this disturbance and maintain cleanliness, the increase in wind speed will affect the increase in operating costs. Therefore, when the required cleanliness level is met, it can be supplied at an appropriate wind speed. Achieve proper wind speed supply to achieve economy.
On the other hand, in order to achieve the stability of clean room cleanliness, the maintenance of uniform airflow is also an important factor. If uniform airflow cannot be maintained, it means that the wind speed is different. Especially on the wall, the airflow will generate vortex along the wall. High cleanliness is actually very difficult.
To maintain a uniform air flow in the vertical laminar flow direction, it is necessary to: (a) The wind speed of the blowing surface must not have a speed difference; (b) The wind speed of the suction surface of the floor return plate must not have a speed difference. If the speed is too low or too high (0.2m/s, 0.7m/s), there will be eddy currents. However, at a speed of 0.5m/s, the airflow is more uniform. Generally, the wind speed of a clean room is 0.25~0.5m. /s between.
influencesClean shedThere are many airflow factors, such as process equipment, personnel, clean room assembly materials, lighting fixtures, etc. At the same time, the diversion point of the airflow above the production equipment should also be considered.
Generally, the air flow diversion point on the surface of the operating table or production equipment should be located at 2/3 of the distance between the clean room space and the partition wall, so that the air flow can flow from the inside of the process area to the work area when the operator is working. The dust is taken away; if the diversion point is placed in front of the process area, it will become an improper air flow. At this time, most of the air flow will flow to the process area, and the dust caused by the operator's operation will be taken to the back of the equipment. As a result, Taiwan will be contaminated and the yield rate will inevitably drop.
Obstacles such as work desks in the clean room will have eddy currents at the junctions, and the cleanliness will be relatively poor near them. Drilling return air holes on the work desks will reduce the eddy currents; assembly Whether the selection of materials is appropriate and the layout of the equipment are perfect are also important factors for whether the airflow becomes a vortex phenomenon.
The fan sucks in air from the top of the FFU,Primary filter, High-efficiency filter, the filtered clean air is sent out to the clean shed at a uniform speed of 0.45m/s±20% on the entire air outlet surface. The uniform layer is formed to make the clean air flow in a vertical unidirectional flow, thus ensuring the cleanliness required in the working area.
Clean shedIt is a simple clean room that can be quickly built. It has the characteristics of fast installation, short construction period, low price, and convenient movement. It is also a good choice for clean room design to control the main production processes in a small environment.