What are the preparations for the installation of high-efficiency filters? What are the requirements for filter installation?

High Efficiency FilterWhat are the preparations for installation? What are the filter installation requirements?

High Efficiency FilterIt is the key component of the clean air system. At present, the filter material used in China is ultra-fine glass fiber paper and ultra-fine asbestos fiber paper, which is used to filter the submicron particles that cannot be filtered by the coarse and medium filters, and the content of which is up to 1um or less, to ensure the clean requirements of the clean room. In order to ensure the filter efficiency and the clean effect of the clean system, the installation of high-efficiency filters must comply with the "Clean Room Construction and Acceptance Code" or the requirements of the design drawings.

1. Preparation before installation

In order to prevent the high efficiency filter from being contaminated, opening the box for inspection and installation must be carried out only after the installation of the air clean system is completed, the air conditioner, the high efficiency filter box, the air duct and the clean room have been cleaned, and the air conditioning system is stabilized only after the trial operation of the individual equipment and the amount of dust blown out of the air duct.

Before installation, check the straightness of the end face of the filter frame or side opening, and the permissible deviation of the end face flatness should not be more than 1mm each; if the end face flatness exceeds the permissible deviation, only the end face of the frame where the filter is installed is allowed to be modified or adjusted, and modification of the frame of the filter itself is not allowed, or the filter media or sealing part of the filter will be damaged, and the filtration effect will be reduced.

2. Installation requirements

When installing the high-efficiency filter, it should be ensured that the direction of airflow is consistent with the direction of the arrow mark on the outer frame. When the high-efficiency filter assembled with corrugated board is installed vertically, the corrugated board must be perpendicular to the ground and not reversed.

The sealing of high-efficiency filters and the frames for assembling high-efficiency filters generally adopts both the top-tightening method and the pressure-tightening method. For cleanliness requirements of strict clean system above level 5, some use knife frame type high efficiency filter liquid tank sealing device.

(1) Installation of the top-tightening and pressure-tightening methods The top-tightening method is characterized by its ability to install and replace high-efficiency filters in a clean room. The compression method is characterized by the ability to install and replace high-efficiency filters only in suspended ceilings or technical mezzanines.

When installing, the filter should be held gently and placed without contamination, and should not be knocked or hit with tools, and it is strictly prohibited to touch the filter paper with hands or tools to prevent damage to the filter material and sealant.

The sealing of the filter and the frame is generally made of closed-cell sponge rubber sheet or neoprene rubber sheet, and silicone rubber coated sealing is also used. The thickness of the sealing gasket is often 6~8mm, positioning paste on the filter frame, the compression rate after installation should be 25%~30%. the splicing method of the sealing gasket is the same as that of the flange connecting gasket of the duct of the air clean system, i.e., trapezoidal or vertebral splicing is used.

When sealing the filter to the frame with a double ring seal, do not block the eyelets on the ring cavity. Both the double ring seal and the negative pressure seal must keep the negative pressure pipe open. Double ring seal. In order to improve the sealing effect of the combination of "sealing and guiding", the openings on the ring cavity, such as the design does not require that the filter with a side length of 484mm or less, one hole on one side, it is appropriate to open holes on 1~2 sides; the filter with a side length of 630mm or less, one hole on one side, it should be opened on two sides; the filter with a side length of 630mm or more, two holes on one side; the filter with a side length of 630mm or more, two holes on one side; the filter with a side length of 630mm or more, two holes on one side. For filters with a side length of 630mm or less, one hole on one side should be opened on two sides.

Filter and frame sealing, such as the use of silicone rubber as a sealing material, in order to ensure good sealing, before applying silicone rubber, the filter and the frame should be cleaned of debris and oil, and then full and uniformly coated with silicone rubber.

(2) The installation of liquid tank sealing method of liquid tank sealing is to improve the cleanliness of the clean room and the development of a sealing method, which overcomes the compression method due to the poor flatness of the end face of the frame, so that the filter sealing is not tight or the sealing gasket layer aging leakage and replacement of the dismantling cycle and other shortcomings.

The device of liquid groove sealing is made of aluminum alloy plate pressed into two-way, three-way, four-way groove connectors, and assembled with screw connections to form a single unit. It is sealed with non-Newtonian sealing liquid in the form of sealant and is suitable for vertical unidirectional flow clean room. The non-Newtonian sealing liquid in the liquid tank is an inert liquid with non-volatile, non-oil creeping, non-corrosive, acid and alkali resistant, non-toxic, with a certain degree of fluidity and good dielectric properties and stable electrical insulation properties. Dip the knife-rack type high-efficiency filter into the sealing tank.

In the installation process, the lifting and connection of the skeleton components may have deviations in elevation and unevenness, which should be leveled as much as possible. In order to ensure that the high-efficiency filter knife frame can be installed smoothly in a limited space, the plane accuracy requires that the deviation of the vertical and horizontal centerline of the liquid tank in place should not be greater than 5mm; and the height difference of the vertical and horizontal centerline of the liquid tank in the vertical direction should not be greater than 3mm, in order to prevent the liquid tank system from running to the liquid level difference close to the maximum value, which will make the liquid tank show the bottom of the bulge and leakage or the local liquid overflow.

After the frame liquid tank is connected, silicone rubber or epoxy resin adhesive and other sealants should be used to seal all the joints and gaps. Then the sealing liquid with a water bath warmed to about 80C dissolved, quickly injected into the tank to reach the design depth, to be condensed after the sealing liquid, you can install high-efficiency filters. When installing the filter, the knife frame should avoid contacting the wall of the tank to avoid forming a leakage boundary; the knife frame should be gently inserted into the liquid tank to seal. The general operator should be on the frame and put down the filter from above, or according to the external dimensions of the filter, the filter can be held diagonally from below over the liquid tank and then aligned to put down.

If the installed filter needs to be moved, the filter can be lifted up a little and then gently lowered into the slot. The installed filter should not be pushed hard to avoid liquid overflow or damage to the filter. When replacing the filter, a pallet should be prepared in advance, and when the filter holder is removed from the liquid tank, the pallet should be placed under the filter immediately to avoid the liquid attached to the holder from dripping into the clean room or contaminating the installed filter.