how does fan filter unit work?

How does fan filter unit work？The working principle is to use the FFU fan filter unit's internal fan (motor + impeller) to suck in air (wind), and the absorbed air (wind) passes through the HEPA (high-efficiency air filter) or ULPA (ultra-high-efficiency filter) filter screen below the FFU, filtering out large particles and dust particles in the air, and finally uniformly delivering the clean air at a wind speed of 0.45m/s ±10% to the clean room.

Clean rooms that can use FFUs are generally above Class 1,000. The basic structure is that the air first enters the clean room from the MAU (first filter, medium-efficiency filter) at the top of the clean room, and then the wind is sent into the clean room through the FFU (second filter, HEPA or ULPA). The wind sent down passes through the raised floor and then enters the return air box to be sent to the top of the clean room.

FFU is a combination of a fan and a filter, also known as a "filtering device with a built-in fan." FFUs are usually installed at the end of the air supply in the clean room, typically placed on a suspended, "dry" gasket-sealed keel frame. The FFU system is characterized by easy installation, flexible wind speed adjustment, and easy change of the clean area, and has been applied in medical, electronic, chip, and biopharmaceutical fields.

FFUs are typically installed at the end of the air supply in the clean room, usually placed on a suspended, "dry" gasket-sealed keel frame. The upper part of the FFU is the fan module, and the lower part is the filter. According to the cleanliness requirements, the filter can be of different levels (HEPA) or ultra (ULPA) filters, providing clean air to the clean room. In addition to overcoming the resistance of the filter at the bottom of the FFU, the fan module also has to overcome the resistance of all the channel components of the entire circulating air to maintain the set operating wind speed. The FFU system is characterized by easy design and construction, flexible wind speed adjustment, and easy change of the clean area, making it one of the popular system forms for industrial clean rooms.