Difference between high efficiency filters with and without partitions

The outer frame of high-efficiency filters without partitions is mainly used: aluminum alloy profile, multi-layer plate frame, aluminum plate frame, and galvanized steel frame, the most used aluminum alloy profile frame, mainly made into a square-shaped structure. Some foreign manufacturers use electrostatic polytetrafluoroethylene fibers (electret) to manufacture high-efficiency filters, commonly known as PTFE.


High-efficiency filters with partitions use ultra-fine glass fiber filter paper as the filter material, with materials such as glue board paper and aluminum foil board folded as the separator, sealed by new polyurethane sealant, with a galvanized sheet, stainless steel sheet, and aluminum alloy profile as the outer frame, and each unit is strictly tested. The filter media is made of ultra-fine glass fiber and PP high-efficiency paper.

The non-spacer plate mainly adopts hot-soluble glue as the separator of the filter element, which is convenient for mechanized production. With the advantages of small size, lightweight, easy installation, stable efficiency, and uniform air velocity, the filters required for large quantities in clean plants mostly adopt the structure without partitions. There are high-efficiency partitions, mostly made of aluminum foil and paper folded as cartridge separators to form air channels. The partition plate is made of high-quality kraft paper, hot rolled into shape or used offset paper as a partition plate. The main purpose is to prevent the divider from shrinking under the influence of hot and cold, dry and humid, thus emitting particles. In the event of changes in temperature and humidity, this partition paper may emit larger particles, resulting in a failed cleanliness test in the cleanroom. Therefore, for premises with high cleanliness requirements, customers should be recommended to use non-spacer HEPA filters. The price of foreign partitioned filters is higher than the price of partitionless ones, so fewer premises abroad use partitioned ones. In addition, the V-shaped passage of a partitionless filter further improves the uniformity of dust-holding capacity and extends the service life compared to the rectangular passage of a partitioned filter. Partitionless filters for ventilation avoid the use of metal parts and are easy to dispose of, meeting increasingly stringent environmental requirements. Apart from certain special applications where high-temperature resistance and high safety are required, partitionless filters can be used instead of partitioned filters.


The reason why there is a difference between the actual size and the nominal size of HEPA filters is that the nominal size is the filter that includes the outer frame and the filter media, while the actual size generally excludes the outer frame and only calculates the width, height, and depth of the filter media as well as the area of the filter media.


High-efficiency filters with partitions are made of ultra-fine glass fiber as filter media, glue board paper, and aluminum platinum as partitions, glued together with wooden or aluminum alloy frames, and have the advantages of high filtration efficiency, low resistance, and large air volume, and are widely used in various local purification equipment and clean plants.


Compared with high-efficiency filters with partitions, they have the advantages of small volume, lightweight, compact structure, and reliable performance under the same air volume.


The number of folds is mainly determined by the degree of tightness of the partition paper and the assembly of the filter paper and the partition paper. The number of filter paper folds without dividers is mainly determined by the height of the filter paper folds and the tightness of the filter paper.