What are the characteristics of and differences between primary filters, intermediate filters, and high efficiency filters used in clean rooms in factories?

Factory clean room usePrimary filterWhat are the characteristics and differences between medium- and high-efficiency filters?

Primary filterApplicable to the primary filtration of air-conditioning system, mainly used for filtering dust particles above 5μm. There are three types of primary filters: plate type, folded type and bag type, with paper frame, aluminum frame and galvanized iron frame, non-woven fabrics, nylon mesh, activated carbon filter material and metal hole mesh, etc., and the protective mesh is made of double-side sprayed iron wire mesh and double-side galvanized iron wire mesh.

Characteristics of primary filters:
Inexpensive, lightweight, versatile and compact.

Primary filters are mainly used for:
Pre-filtration for central air-conditioning and centralized ventilation systems
Pre-filtration for large air compressors
Clean return air system
Pre-filtration of localized high efficiency filtration units
High temperature resistant air filter with stainless steel frame, high temperature resistant 250-300°C filtration efficiency
Primary filters, commonly used in the primary filtration of air conditioning and ventilation systems, are also suitable for simple air conditioning and ventilation systems that require only primary filtration.

G series primary air filters are divided into eight varieties, namely: G1, G2, G3, G4, GN (nylon mesh filters), GH (metal mesh filters), GC (activated carbon filters), and GT (high-temperature-resistant primary filters).

Medium-efficiency filters belong to the F series of air filters, and the F series of medium-efficiency air filters are divided into bagged and non-bagged types, of which the bagged types include F5, F6, F7, F8, and F9, and the non-bagged types include FB (plate-type medium-efficiency filters), FS (spacer-type medium-efficiency filters), and FV (combination-type medium-efficiency filters).

Application of medium efficiency filters:
It is mainly used in the intermediate filtration of central air-conditioning ventilation system, pharmaceuticals, hospitals, electronics, food, and other industrial purification; it can also be used as the front-end filtration of high-efficiency filtration in order to reduce the load of high-efficiency overconsideration, and prolong its service life; because of the large wind surface, it has a large amount of empty dust and low air velocity, and it is considered to be the best intermediate-effect filter structure at present.

Characteristics of medium efficiency filters:
1. Capture 1-5um particles of dust and all kinds of suspended matter.
2. Adopting hot melt process to stabilize the structure and reduce the risk of breakage and leakage.
3. High air volume.
4. Low resistance.
5. High dust capacity.
6. Can be cleaned and used repeatedly.
7. Type: frameless and framed bag type.
8. Filter material: special non-woven fabric or glass fiber.
9. Efficiency: 60%～95%@1～5um.
10. Maximum temperature and humidity for use: 80°C, 80%.

High-efficiency filters are mainly used to capture particles of dust and various suspended matters below 0.5um. It adopts ultrafine glass fiber paper as the filter material, offset paper, aluminum film and other materials as the dividing plate, and is glued with aluminum alloy of wooden frame.

High-efficiency filters are characterized by high filtration efficiency, low resistance and large dust capacity.

High-efficiency air filters can be widely used in the air conditioning end air supply of clean rooms in such industries as optical electronics, LCD manufacturing, biomedicine, precision instruments, beverage and food, PCB printing, etc. The high-efficiency and ultra-high-efficiency filters are both used in the end of clean rooms, and can be categorized by their structure. High-efficiency and ultra-high-efficiency filters are used at the end of clean rooms, and can be categorized by their structural forms: high efficiency filters with partition, high efficiency filters without partition, high efficiency filters with large air volume, ultra-high efficiency filters, and so on.
In addition there are three kinds of high-efficiency filters, a kind of ultra-high-efficiency filters, can do to purify 99.9995%. a kind of antimicrobial type high efficiency air filter without partition, has the effect of antibacterial, to prevent bacteria from entering the clean room, a kind of sub-high-efficiency filters, the price is cheaper than before, more used in the purification of the space of the requirements of the not very high.

Air filters are generally used in clean workshops, clean factories, laboratories and clean rooms, or for dust control of electronic machinery and communication equipment. It adopts ultra-fine glass fiber paper as material, adhesive version of paper, aluminum mold and other materials as split board, and aluminum alloy glued with wooden frame.