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Electronic industry clean room FFU structure brief introductio

Industrial modular Clean Room time:2021/05/13 17:51:05 click:603

Electronic industry clean room FFU structure brief introduction

I. The appearance of FFU

At present, the FFU produced by all the manufacturers in the world can be divided from the appearance: 1. There are two kinds of FFU from the shape, one is cuboid, the other is slope. The upper part of FFU is made into a slope shape, which plays a role of diversion and is conducive to the flow and uniform distribution of airflow. FFU generally relies on alternative methods to equalize the flow (more on this later). 2. There are two kinds of structure, one is the whole and the other is the split. The split shape FFU has the following advantages: (1) The filter replacement becomes convenient; ② reduces the labor intensity in the installation process; The overall shape of the FFU has the following advantages: ① increased the sealing of the FFU, effectively prevent leakage. ② is beneficial to reduce noise. ③ is conducive to reducing vibration.

Head filter

II. Components of FFU

At present, a variety of FFU is composed of the following parts at most (from top to bottom, from inside to outside order), depending on different manufacturers components may be reduced. 1. Pre-filter; 2. Outer shell; 3. Air duct connecting parts; 4. Motor 5. Impeller; 6, air balance device; 7. Filter; 8, metal protective net; 9, knife edge; 10. Control components.

Below, we analyze and introduce each component:

1. the pre-filter: generally can be cleaned polyurethane foam, mainly to prevent the construction, maintenance or other accidents caused by debris and may cause damage to the filter.

2. outer shell: composition materials are aluminum plate, aluminum alloy, hard plastic, stainless steel and so on, different manufacturers and different use environment have different choices, thickness of about 1.2~2.0, depending on the thickness of some can be manned.

3. the air duct connecting parts: in the clean level is low (≤1000 federal standard 209E) occasions, at this time there is no hydrostatic box on the upper ceiling, with the air duct connecting parts of the FFU makes the connection between the air duct and the FFU very convenient.

4. Motor: At present, AC motor and DC motor are used in FFU. DC motor has large volume, high cost, easy control and high energy consumption. The size of the AC motor is small, the cost is low, the control needs the corresponding technology, and the energy consumption is low. The motor life of today's FFU ranges from 40,000 to 100,000 hours. Some excellent motors have corresponding technology, such as oil-free lubrication, sealed bearings, with overheat protection, commutator life significantly increased, etc.

5. impeller: impeller has two forms, forward leaning and backward leaning, forward leaning is conducive to increase the vector flow of air distribution, enhance the ability of dust removal. Tilting back helps to reduce energy consumption and noise.

6. air balance device: with the continuous popularity of FFU, most manufacturers have begun to assemble air balance device, used to adjust the FFU outlet airflow, so as to improve the air distribution of clean room. At present, this balancing device is divided into about three kinds: one is the orifice plate, mainly through the density distribution of the holes on the plate to adjust the FFU outlet airflow. One is the grille, mainly through the density of the grille to adjust the FFU outlet airflow. The other is the dynamic curve, which mainly induces the flow of air through the shape of the curve and adjusts the flow through the density distribution of holes on the curve.

7. Filters: The filters used by FFU are the same as other filters used in clean houses, and will not be described here.

8. metal protective net: metal protective net mainly plays a protective role in the filter, most of them are anti-static.

9. knife edge: when the FFU is used in some special occasions, the FFU with the knife edge can be used to seal the tank, so as to meet the requirements of high sealing.

10. control unit: the control of FFU can be roughly divided into multi-file switch, continuous adjustment, computer control and other functions, at the same time to achieve a single control, partition control, alarm, running state display and so on.

The control of FFU system includes multi-shift switch control, stepless speed control, remote control, computer group control and other control methods. Generally, according to the control mode of the central air conditioning system in the clean room, the number of FFU in the clean room and the requirements of Party A on the FFU control system to choose an economic and reasonable control mode.

In summary: with the rapid development of modern electronic industry, the air cleanliness level of clean rooms will be required to be higher and higher. With the maturity of HEPA, UHEPA filter technology, the improvement of FFU system theory and the accumulation of practical application experience, as well as the development of manufacturing level, make the FFU system meet ISO3∽ISO9 (that is, 1 level ∽1 million level) clean room air clean grade use requirements at the same time, It provides a better direction for the upgrade of clean room in the future. The FFU system consumes less energy than the AHU system and reduces the cost of energy for enterprises, which is in line with the current mainstream direction of energy conservation. Through the analysis of the characteristics and control mode of FFU, we believe that the application of FFU in clean room will have a broader prospect.