Melt pumps [EXTRU]

Melt pumps for extrusion

The extrusion gear pump is mainly used in connection with extruders or kneaders. They lower the naturally existing pulsation and uneven transportation, particularly of single-screw extruders.

The extrusion pump is also used as a melt pump. It takes over the establishment of the required transport pressure, which is needed for the downstream equipment.

Efficient pressure build-up

In the gear pump, the pressure build-up occur significantly more efficiently than in the extruder itself. The extruder is relieved through the use of an extrusion pump. Significantly less energy or heat is added to the polymer. The melt pump thereby contributes to the gentlest possible transportation. The EXTRU pump is indispensable for the production of precise foils or micro-granulate.

Design examples for melt pumps [EXTRU]

Robust and flexible

The robust design and wear-resistant materials make the EXTRU indispensable for extrusion. It can also be used to transport natural rubber and soft PVC through different special designs.

The WITTE fast-changing color design is perfect for master batch applications with frequently changing colors.

Advantages:

Technical data

Housing	Heat-resistant carbon steel, for example, 1.6582 · Stainless steel 1.4313 · optional with coating · optional with coating
Gear Shafts	Tool steel · Nitriding steel · Special steel · optional with coating · Helical gearing · Herringbone gearing (for transportation with very low pulsation)
Shaft seals	Threaded shaft seal · Stuffing box
Heating	Electric through heating cartridges · Cover heating optional
Friction bearing	Tool steel · NiAG (nickel-silver) · Aluminum bronze · Special materials · optional with coating

Operating parameters

Viscosity	Up to 40.000.000 mPas
Temperature	Up to 400°C
Suction pressure	Vacuum up to max. 120 bar
Transport pressure / differential pressure	Up to 250 bar. Special designs also for higher differential pressures
Pump sizes	From 4,7-22-22 (4,7 cm3/U – 10 kg/h) to 12.000-280-280 (12.000 ccm/U). Sizes with smaller gears for higher differential pressures are possible, p.e. 690-140-90.