Ultra-fine foreign material filter

Abstract

An ultra-fine foreign material filter belongs to the technical field of liquid filter. The ultra-fine foreign matter filter comprises a bucket body consisting of a heating jacket, an upper close cover arranged on the upper part of the bucket body, a filtering element device arranged in a bucket body cavity of the bucket body in a hanging way, a lower close cover arranged on the lower part of the bucket body, a secondary filter device, a first sealing and fixing device and a second sealing and fixing device; the upper close cover consists of an insulation jacket which is communicated with the heating jacket, the lower close cover is provided with a lower close cover insulation jacket which is communicated with the heating jacket, the lower close cover is further provided with a filtrate outlet and a heating medium introducing interface, the secondary filter device is clamped between the lower close cover and the lower edge of the bucket body, the first sealing and fixing device consists of a first seal ring and a first fastener, and the second sealing and fixing device consists of a second seal ring and a second fastener. The ultra-fine foreign matter filter is characterized in that the first seal ring and the second seal ring are wrapped seal washers with first U-shaped cavities. The ultra-fine foreign material filter has the advantages of having ideal filtering effect, avoiding seepage and gas leakage and facilitating the protection of the device and the prevention of environmental pollution.

Description

technical field [0001] The invention belongs to the technical field of liquid filters, and in particular relates to an ultrafine foreign matter filter, which is used for filtering out ultrafine foreign matters in liquid materials. Background technique [0002] For some liquid materials with extremely strict foreign matter requirements, such as liquid pyromellitic acid (PMA) and pyromellitic dianhydride (Pyromellitic Dianhydride, PMDA), the filtration of foreign matter must use ultra-fine foreign matter filtration This is because PMA and PMDA products are ultimately used to manufacture high-end electronic-grade polyimide films. The thinner the electronic-grade polyimide film, the stricter the requirements for foreign matter in PMA and PMDA. At present, the thickness of polyimide film has been processed to 1-1.5 μm abroad, and the number of foreign matter in PMA and PMDA is required to meet the following requirements: under a magnifying glass of 40 times, the number of ultra-f...

AI Technical Summary

Problems solved by technology

[0004] However, the technical solution of CN101269280A has a defect in the sealing aspect. The last line on page 4 to the second line on page 5 of the specification states: After the filter element device is set up, add a sealing ring, and use a fastening device such as a bolt to add a fastener The combination of the upper cover and the barrel is connected, and at the same time, the flange edge of the supporting basket and the first and second flanging clips are hung between the matching surface of the upper cover and the barrel

And then from the structure shown in the embodiment diagram (Fig. 2) of this patent, it can be known that the seal ring is an annular sheet seal ring, yet, due to the particularity of the solvent in the PMA, PMDA production process (volatile organic acid solvent) And the temperature is as high as above 120°C. Therefore, during the filtration process, the solvent seeps out from the filter medium, which not only causes corrosion of equipment and pollutes the environment, but also is not conducive to the health of workers in the workplace.

Therefore, although CN101269280A can meet the filtration requirements for ultra-fine foreign matter, and the filtration accuracy reaches 0.01-0.1 μm level, there is still a need for improvement in sealing

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