Discharge pumps [POLY]

Gear pumps for the discharge of highly viscous media

Polymer discharge pumps

Reliable and robust pumps are needed to empty reactors and containers particularly during the polymerization process. The pumps transport the melt throughout the process. The highly viscous material must be transported from a reactor under vacuum. Discharge pumps from the POLY series from WITTE are specifically created for this task. The customer can choose between a standard design or an individual design according to their requirements.


Design versions for Polymer discharge pumps

Discharge pumps for polymerization production

These pumps achieve the best efficiency through optimized shaft and bearing geometry. The need for energy is kept low allowing the operating costs to be optimized. The POLY is offered in different variations. Versions with classic or shortened inlet geometries are just as possible as versions in the LowNPSH Design.

Pumps with shortened inlets guarantee the quick feed of melt to the gear pumps. All POLY discharge pumps have the largest possible inlet openings with optimized flow geometry to avoid increased friction, decelerated inlet of the medium into the pumps as well as to reduce additional heat input. Different material combinations make these pumps reliable partners in the polymer industry, which can also be operated reliably under the most extreme of conditions.

Request for a polymer discharge pump [POLY] quotation

Please fill out the following form so we can create an offer that is exactly customized to your needs. One of our sales engineers will examine your request and contact you to discuss your application in detail.

Request a quote

Advantages at a glance:

  • Seals
  • Housing
  • Tempering
  • Bearings

  • Seal variations

    Different seal variations for the secure and non-leaking operation of the pump, and also for difficult applications, conditions and processes.

  • Housing variations

    We can offer the housing from the POLY series in different variations specific to your application. The flange can be round or square, long or short, horizontal or vertical, screwed or clamped, to ensure the best possible connection to the reactor.

  • Tempering

    The POLY is extremely flexible and can be used for different areas of application. All components such as seals, housings and endplates are tempered separately.

  • Bearings

    The lubricant flow can be changed through a setting screw. Depending on the medium, process or viscosity, the seal from the pump is regulated through the threaded shaft seal. The customer is therefore flexible and can quickly react to changes as needed.

[Translate to American:] Polymer discharge pumps in classic design

Technical data

Unalloyed and alloyed steel · Cast steel · optional with coating
Nitrided steel · Tool steel · Special steel · optional with coating · Helical gearing · Herringbone gearing
Axial shaft seals
(Vacuum) threaded shaft seal · Stuffing box · Combination of threaded shaft seal and stuffing box · double, locked mechanical seal
Heat transfer oil · Steam
Friction bearings
Tool steel · NiAG (nickel-silver) · Al bronze · Special materials · optional with coating

Operating parameters

Up to 40.000.000 mPas
Up to 350 °C
Suction pressure
Vacuum up to max. 15 bar
Transport pressure / differential pressure
Up to 250 bar (4642 psig). The values listed are standard values and must not coincide under certain circumstances. Other values are available upon requests.
From 4.7-22-22 (4.7 ccm/rev – 10 kg/h) to 25,000-360-360 (25,000 ccm/rev – 52,000 kg/h). Sizes with wider gear pumps for lower differential pressures are available by default, for example, 3,170-152-254 (3,170 ccm/rev).

Application examples for WITTE polymer discharge pumps from the POLY series


References POLY

POLY discharge pump with fitter
POLY discharge pump standing
Picture of a POLY discharge pump
WITTE fitters with POLY discharge pump