Explosion-proof air shower filter replacement procedure (primary efficiency + secondary efficiency, including explosion-proof safety regulations)
Key points: Full power-off explosion-proof operation, anti-static, explosion-proof dust environment must be free of dust flying, conduct leak detection and wind speed measurement after replacement. Proceed step by step according to the standard procedure and follow it directly.
1. Preparations before replacement (explosion-proof safety first, must be done)
Stop the machine and cut off the power supply
Turn off the main power supply, hang a sign and lock (LOTO), do not touch and disassemble with power on; Do not open the cover in dust / flammable and explosive areas with power on.
Personal protection
Wear anti-static clothing, gloves, mask, use dust-free tools, do not use iron tools to strike or rub to generate sparks.
Clear the site
Empty the internal debris of the air shower room, clean the return air duct and the surrounding dust of the nozzle, reduce dust flying.
Component verification
Primary efficiency: G4 plate-type filter
Secondary efficiency: H13/H14 with or without partitioned / without partitioned high-efficiency filter (size consistent with the original factory)
Do not use ordinary high-efficiency filters from non-explosion-proof areas as substitutes, the sealing rubber strip must be intact.
2. Replacement of primary efficiency filter (the simplest, once every 3-6 months)
Open the inspection panel of the air shower room return air inlet (lower part / side of the box).
Remove the old primary efficiency filter, wrap it in a sealed bag and take it out to avoid dust scattering.
Clean the accumulated dust in the filter frame.
Place the new primary efficiency filter flatly, with the arrow pointing towards the airflow direction (towards the fan side).
Press the clamps tightly, seal it tightly, and reinstall it on the inspection panel.
Explosion-proof workshop with lithium batteries, aluminum powder, dust: Replace once every 2-3 months, do not use repeatedly after long-term water washing.
3. Replacement of secondary efficiency filter (critical, once every 6-12 months, replace immediately if the pressure difference exceeds the limit)
Step 1: Open the inspection opening of the top static pressure box
After cutting off the power supply, open the top inspection cover of the air shower room (all explosion-proof screws evenly loosen, do not use violent knocking).
Do not use metal tools to forcefully collide the box body in an explosion-proof environment to prevent sparks.
Step 2: Remove the old secondary efficiency filter
Loosen the pressure strip / pressure plate, gently remove the old secondary efficiency filter.
The old secondary efficiency filter is sealed with a plastic bag and taken out, do not shake and cause dust flying in a dust / flammable and explosive environment.
Clean the dust, oil stains, and residual glue inside the static pressure box.
Step 3: Install the new secondary efficiency filter (focus on sealing)
Check that the edge frame and sealing strip of the filter are undamaged and undented.
The air flow direction arrow of the filter is facing down (towards the nozzle), align and center it.
Evenly tighten the screws around the pressure strip, tighten diagonally in turns, ensure no air leakage in all sides, do not allow unilateral pressure tightening.
Explosion-proof area: The screws must be tightened to prevent vibration and loosening from friction and static electricity.
Step 4: Restore the cover plate
Install the top inspection plate, evenly lock the explosion-proof screws, ensure the sealing pad is intact, and ensure the explosion-proof cavity is sealed.
4. After replacement, debugging and testing (explosion-proof + clean double acceptance)
Power on for trial operation, turn on the fan, check for air leakage and abnormal sounds.
Measure the blowing shower wind speed: standard 25–30m/s, if the wind speed is insufficient, check the secondary efficiency seal.
PAO leak detection (must be done in a clean workshop): Leak detection of the secondary efficiency filter and frame, no leakage.
Check the interlock of the double doors, explosion-proof electrical equipment, and normal grounding.
Make a replacement record: date, model, pressure difference, wind speed, test results.
5. Special prohibitions in explosion-proof environment (very important)
Do not replace the filter with power on, do not open the static pressure box with power on.
Dust explosion (lithium batteries, aluminum powder): During the replacement, dust must not be scattered, the old filter sealing tape must be taken out of the workshop for processing.
Do not use damaged, aged sealing strips, non-original factory size high-efficiency filters, which will cause air leakage, pollution + static electricity hazards.
After replacement, confirm that the box body is grounded normally, no explosion-proof static electricity problems.
6. Replacement cycle reference
Primary efficiency filter: ordinary environment 3–6 months; flammable and explosive dust environment 2–3 months
Secondary efficiency filter: ordinary environment 6–12 months; dust heavy / high cleanliness environment 4–6 months If the pressure difference gauge exceeds 200 Pa or the wind speed significantly decreases → Immediately replace it