What should be noted when using the polyurethane high pressure foaming injection machine?

1. Safety protection and operating specifications

Personal protection

When operating the polyurethane high pressure foaming injection machine, you need to wear protective glasses, rubber gloves and work clothes to avoid polyurethane A/B materials from contacting the skin or splashing into the eyes. If A material contacts the skin, it must be washed with soapy water immediately; if B material splashes into the eyes, it must be rinsed with clean water for 15 minutes and seek medical attention.

The working environment must be ventilated to prevent the accumulation of volatile gases (such as foaming agent vapor). In high temperature environments, exhaust and pressure reduction must be performed before opening the sealing cover.

Equipment safety inspection

Before starting the equipment, check whether the pipeline is leaking, whether the nozzle is blocked, and whether the pressure gauge and thermometer are normal. Ensure that each switch is in the initial state and the electrical system is well insulated.

2. Parameter control and process optimization

Temperature and pressure setting

Temperature control: The heating temperature of the material tank is usually set to 40-60℃, and the water temperature is controlled at 20-30℃ (too high will easily lead to low foam density and defoaming).

Pressure regulation: The air pressure of material tank A is recommended to be 0.25-0.3MPa, and that of material tank B is 0.15-0.2MPa. The pressure difference between the two should be ≤5bar to prevent cross-material or uneven mixing.

Flow and mixing ratio

Accurately adjust the A/B material flow valve to ensure that the ratio meets the formula requirements.

When using a self-cleaning mixing head, ensure that the residual mixture is automatically cleaned after each injection to avoid blockage.

3. Equipment maintenance and fault prevention

Daily cleaning

Immediately clean the nozzle and mixing chamber with a special cleaning agent after operation to prevent the residue from solidifying.

Regularly check the lubrication system: the self-lubricating gun head needs to clean the DOP filter, and the non-self-lubricating gun head needs to be manually filled with DOP lubrication 3-4 times a day.

Maintenance of key components

Check the hydraulic station return oil filter to prevent clogging by foaming residue; replace the hydraulic oil regularly.

Avoid using a metal scraper to clean the nozzle to prevent scratching the piston rod or inner wall, which may cause seal failure.

4. Environment and material management

Raw material storage and handling

Polyurethane raw materials need to be stored in a sealed manner to prevent moisture absorption or volatilization. Stir before use to prevent deposition and stratification.

If flame retardant properties are required, flame retardants can be added, but their compatibility with the raw materials must be ensured.

Environmental adaptability

During spraying, the nozzle should be 30-50cm away from the working surface and move at a constant speed. Multi-layer spraying should be carried out after the previous layer is cured.

Avoid working in high temperature (>30℃) or low temperature (<10℃) environments to affect the quality of foam molding.

5. Emergency handling

Blocking or abnormal pressure: stop the machine immediately, check for blockage in the mixing chamber or pipeline, and force operation is strictly prohibited.

Leakage or fire: cut off the power supply, use a dry powder fire extinguisher, and do not use water to extinguish electrical fires.

Comparison with other foaming technologies