Melt pumps and screen changers for foam production lines

XPS insulation board, PET foam, KT board, EPE pearl cotton special melt pump, also known as melt metering pump, for a variety of plastic, rubber, elastomer and other materials extrusion system. It is used for conveying, pressurizing and metering of high temperature and high viscosity polymer melt. Its main function is to pressurize and stabilize the high temperature melt from the extruder and keep the melt flow accurately and steadily into the extruder head.

Application of melt pump in XPS foam production line

1.Φ135 feeding screw parameters: 75KW motor, 8 temperature zones: 172℃, 156℃, 160℃, 160℃, 144℃, 218℃, 180℃ The temperature is 240℃ after the screen changer.

2.Φ150 extrusion screw parameters: 55KW motor, 8 temperature zones: 202℃, 162℃, 158℃, 146℃, 110℃, 66℃, 75℃, 93℃.

3. Die parameters: the plate specifications 60*2 60*2.5 60*3 60*3.5 60*5 60*10 Die temperature 150℃

4. gas injection parameters: foaming gas is CO, injection pressure is 20-25MPa.

The melt temperature affects the viscosity and strength of the material, which affects the outlet pressure of the melt pump and the foaming effect, under normal extrusion conditions, the lower the melt temperature, the better the foaming effect, the ideal temperature of foaming is 120-150℃.

The addition of melt pump can stabilize the extrusion outlet pressure fluctuations, so that uniform extrusion is possible, improve the hardness of XPS extruded sheet material, and can reduce the specific gravity.

Non-stop screen changer The plastic products process is special high foaming class, from the start to normal production needs a period of time, which is also a cooling process, in the middle of the non-stop waste waste and scrap is not good recycling. Traditional screen changer aggravate this phenomenon, and easy to leak material. kt board, EPE pearl cotton special screen changer for low temperature for the characteristics of the screen has a good solution, elastic sealing system and can automatically compensate, sealing pressure increases with the increase in melt pressure of the random head (proportional) never leak material. The net change time is short, the impact on production is small, the net changer normal use maintenance-free. Thickness of more than three millimeters of EPE pearl cotton production can also use a more innovative structure of the multi-station screen changer, due to the design of the "bypass pressure stabilization" system, can be achieved when the screen change without stopping, no pressure drop, no piece of film, completely avoid the interruption of various losses caused by the screen change.