Gear melt pump rubber extrusion

The advantages of using a gear melt pump for extrusion are the very efficient formation of pressure and constant output and hence the dimensional accuracy of the extrudate that is well known in the plastics and thermoplastic materials industry where effective use of gear pumps has been effective. However, it has only been applied to the rubber industry in recent years. The research work in this field has been increasing in recent 3 years.

The initial difficulties encountered in the rubber melt pump extrusion process were mainly the damage to the gear pump and the high viscosity of the compound. Therefore, many applications require that the rubber filter be filtered before the gear rubber melt pump to prevent the nails or internal mixer from getting into the gear pump and damaging the rotor. In addition, since the size of the gear melt pump has limited the output, the application in the past in the tire extrusion line has been limited. An extruder-gear pump combination designed specifically for new tire extrusion with the required strength and extrusion throughput has been developed and has been successfully tested. These tests demonstrated that extrusion of a standard SBR compound with an extrusion speed of 1800-2200 kg / h and a high viscosity NR compound (ML (1 + 4) )> 700) is from 1000 to 1600 kg / h, which corresponds to the extrusion of a conventional single screw 1500 mm extruder.