How to solve the leakage of the DOP HEPA box?

DOP HEPA box is a high-efficiency air outlet with a replaceable high-efficiency filter in a liquid-sealed manner. DOP HEPA box is an intermediate device in the clean space air supply system of the purification project. The purpose is to ensure that the air obtains the ideal static pressure before passing through the high-efficiency filter so that the high-efficiency filter can be used and protected reasonably.
When encountering problems such as leakage in the DOP HEPA box, how to deal with it? After installing the HEPA box, we generally need to perform leak detection on the surrounding areas of the HEPA box. These main parts need to be checked one by one:
(1) The weld area around the box shell, especially the joint area of ​​the high-efficiency filter outlet box, must be fully welded or glued inside and outside the seam.
(2) The sealing knife edge position inside the box should have four straight edges and the knife surface should be basically on the same plane. It can also be checked with an aluminum plate, plexiglass plate, or PVC plate.
(3) The corner where the blade meets the blade: The weld should be continuous and polished, and there should be no welding slag, nodules, pits, etc.
The following points are generally required for the leakage inspection of the DOP HEPA box frame:
(1) The sealing of the joints at the frame joints (two-way, three-way, and four-way) is the most critical point and one of the biggest difficulties.
(2) The overall flatness of the frame: First, the whole needs to be adjusted to be flat. Secondly, after being subjected to force by people, the joints will become loose and the frame will deform. At this time, it needs to be adjusted again.
(3) After the adjustment, all the joint sections of the frame need to be sealed with glue, not only the contact surface of the high-efficiency filter.
Finally, the gel seal HEPA filter needs to be re-inspected to check the leakage one by one:
Generally speaking, high-efficiency filters are leak-tested before leaving the factory, and the focus of the inspection is on the quality of the filter paper itself and the sealing quality of the filter paper and the frame. However, due to the special structure of the liquid tank's high-efficiency filter, sometimes it is difficult to take care of the situation, resulting in leakage during the high-efficiency air outlet inspection. Therefore, it is necessary to conduct a visual inspection of the process requirements for glue injection and interface sealing:
(1) The interface section joints around the tank must be pre-applied with silicone before glue injection.
(2) The joints of the high-efficiency filter frame, especially the corners around the edges, must be sealed with glue around the edges.
(3) During the installation of the gel seal filter, it should be installed quickly and at one time. The gel seal air filter that has been repeatedly disassembled is prone to needing to be refurbished.