What is the difference between a laminar flow hood and FFU?

    Many people think that FFU is a laminar flow hood, and laminar flow hood is the Chinese meaning of FFU. This is not the case. They are two things. Today I will talk about the difference between a laminar flow hood and FFU.
The full English name of FFU is Fan Filter Unit, and the Chinese professional term is fan filter unit (unit), while laminar flow hood refers to purification equipment that can form a vertical one-way flow. Structurally speaking, FFU is hoisted, while the laminar flow hood is a bracket installation. The laminar flow hood can be regarded as an evolved version of the FFU. It is flexible to install and the filter replacement is more convenient.
    FFU can be widely used in clean rooms, clean workbenches, clean production lines, assembled clean rooms and local 100-level workbenches, and can be connected in a modular manner. FFU is equipped with primary and high-efficiency two-stage filters. The fan sucks the air from the top of the FFU and filters it through primary and high-efficiency filters. The filtered clean air is sent out at a constant wind speed of 0.45M/S±20% on the entire air outlet surface. Suitable for obtaining a high-level clean environment in various environments.
    Laminar flow hoods are currently widely used in precision machinery, electronics, pharmaceuticals, food, fine chemicals, and other departments. The structure is more complex than FFU. It is a local purification equipment with relatively low environmental conditions. It is used to provide relatively high local cleanliness and is suitable for Renovation projects, and the overall requirements are not very high, but only meet local requirements. It can be used alone or in parallel in a large area. It is mainly composed of a box, a fan, a primary air filter, a damping layer, lamps, etc. The outer shell is spray-cast. This product can be hung and supported on the ground. It has a compact structure and is easy to use. It can be used individually or connected in multiple units to form a strip-shaped clean area.
    FFU can provide high-quality clean air for clean rooms and micro-environments of different sizes and cleanliness levels. In the renovation and renovation of new clean rooms and clean factory buildings, the cleanliness level can be improved, noise and vibration can be reduced, and the cost can be greatly reduced. It is easy to install and maintain, making it an ideal component for clean environments. It is used in large areas to provide a clean environment. It is mostly used for level 100 or higher. Generally, the floor form is required to be a raised floor with return air ducts, and the cleanliness of the lower level must also be ensured around this level.
    The laminar flow hood adds a flow-equalizing plate, which improves the uniformity of the air outlet, protects the filter to a certain extent, and has a more beautiful appearance. The air return locations are also different. The FFU returns air from the ceiling, while the laminar flow hood returns air from indoors. There are differences in structure and installation location, but the principle is the same, they are all air-purifying equipment. However, the application range of the laminar flow hood is not as wide as FFU.