How should polyurethane foaming equipment be maintained in winter? Manufacturers recommend paying close attention to daily cleaning. After production, clean the discharge and feed ports so no material is left to affect heat dissipation and later production. Clean the machine surface with a soft brush or damp cloth, and add lubricating oil between moving parts to reduce wear and extend service life.
During maintenance, regularly check switches, wiring and values: make sure wiring is safe with no tangles or damaged insulation, values are in the correct position and switches work. Test current and voltage regularly to prevent sudden failures. If the machine is idle for a while, note the following.
Downtime Maintenance Steps
- Store the machine in a cool, ventilated place, never in direct sunlight; keep the surface and electrical panel clean.
- Change the hydraulic oil after 6 months of use, and clean the tank interior at the same time.
- Regularly check oil circuits and pump connections for looseness.
- Replace the O-rings in the gun head regularly, and the pump shaft seal as needed.
- Short idle of about 7 days needs no special treatment.
- For medium idle of 10–20 days, run the machine for 3–5 minutes every 10–20 days to keep the raw materials circulating under pressure.
- For long idle, flush the entire isocyanate (black material) system; if regular circulation is possible, flushing is not needed.
Flushing Procedure
- Drain the raw material from the tanks, then open the discharge port under the pump to drain the pump.
- Add a cleaning agent of about 20% dichloromethane and 80% dioctyl phthalate (enough for machine recirculation), circulating at low and high pressure.
- Circulate with pure DOP and then drain.
- Circulate with pure dioctyl phthalate; the last batch can be left in the machine and drained before the next production day.