What are the pre-post jobs for foam machinery usually?
When the foam is mechanically ventilated, try not to make the wind pressure too large. The inner wall of the air duct should be lubricated as much as possible, and the bending radius should be as large as possible. The pipeline should be a good conductor of electricity. All lines should be grounded to prevent static ignition. The conveying speed should not exceed 8m/s to prevent damage to the beads.
The beads are all moist. After being released from the pre-expansion machine, the foaming agent in the honeycomb cells is condensed due to the sudden cooling of the air, so that negative pressure is formed in the cells. Therefore, the beads should be placed for a period of time after pre-expansion. Balance the internal pressure and external pressure in the cells, avoid cell collapse, and make the beads elastic.
Aging improves the further expansion of pre-formed beads in the molding process, the fusion between beads and the elasticity of beads, which is conducive to improving the quality of foam machinery production.
The beads are cooled by air, and the foaming agent and water vapor in the pores of the cells are condensed into liquid, so that a negative pressure is formed in the cells.
The air penetrates into the inside of the cell through the cell membrane, so that the pressure in the cell is balanced with the external pressure, which will make the pre-expanded beads elastic. After the pre-release of the foam machinery, the corresponding preparations should be made.