Leak detection methods for high efficiency filters
Leak detection methods for high efficiency filters1. First check whether the level of DOP solvent in the aerosol generator used is higher than the low level. If it is insufficient, it should be added in time.2. Then connect the nitrogen cylinder to the aerosol generator and turn on the temperature control switch of the aerosol generator until the red light changes to green to indicate that the temperature has reached the required value (approximately 390 - 420°C). 3. Connect one end of the test hose to the upstream test port of the aerosol photometer and place the other end on the inlet side of the filter being tested. If the DOP generator is small at this point and does not reach the required concentration, it can be placed in the static pressure box of the filter being tested procedure, while the laminar flow bench can be placed directly at the suction inlet of the fan. Then turn on the control switch of the photometer and set the test value to 100. 4. Open the control switch of the nitrogen gas, control the pressure in it between 0.05 - 0.15Mpa, slowly open the oil valve of the aerosol generator, control the test value of the photometer between 10 - 20, and wait until the test value is stable, enter the concentration measured upstream and you can carry out subsequent scanning, inspection and other operations. 5. Connect one end of the test hose to the downstream test port of the aerosol photometer and use the other end to scan the air outlet side of the filter, bracket, etc., remembering to be approximately 3 - 5cm away from the filter, then scan back and forth along the internal sides of the filter, etc., keeping the speed below 5cm/s. 6. The whole test covers the filter media, the connection between the filter media and the interior, the connection between the frame gasket and the support frame, the connection between the support frame and the roof, etc. The main check is for any damage or leakage of small pinholes in the filter media, the frame seal, the gasket seal, etc. 7. The value displayed by the instrument on the photometer is the penetration rate of the filter. When the efficiency of the filter is below the controllable standard, you can use epoxy silica gel to plug the leak or tighten the bolt, suspend the operation if necessary and replace the filter, and check again after the replacement, knowing that the value displayed by the instrument is within the acceptable range, indicating that the equipment can operate normally. |