Extrusion Pumps  Manufacturers, Traders, Suppliers

WITTE offers pumps for applications in borderline areas. We develop durable, standardised or customised solutions of the highest precision. For more than 35 years WITTE has specialised in the development of gear pumps for industrial applications. It is our endeavour to always guarantee the customer the highest level of process reliability and to match the pumps exactly to the application and the process. In this way we guarantee the best efficiency and durability of our pumps. Reduced maintenance costs and intervals due to matched material pairings guarantee a fast payback the investment costs. We have been working successfully for many years with well-known companies and innovation drivers from the industry and are constantly developing new solutions. Should we not have the right solution at hand, we develop together with our customers the suitable product. We accompany our customers during the entire project from the prototype to the final product. Experts from sales, project management and design form the project and development team and keep us informed of the project status at all times. More than 35 years of experience and the knowledge of our competence team flow into each of our pumps.

Housing
Heat resistant carbon steel, e.g. 1.6582 · rust-free stainless steel 1.4313 · with optional coating
Gears
Tool steel · nitrated steel · special steel · with optional surface coating · helical gearing · herringbone gearing (for extremely low-pulsation conveyance)
Friction Bearings
Tool steel · NiAg (nickel-silver) · Al-bronze · special materials · with optional surface coating
Shaft Seal
Viscoseal · stuffing box
Heating Systems
Electrically, by means of heating cartridges · optional cover heating
Operating Parameters
Viscosity
up to 40000 Pas
Temperature
up to 400°C (752°F)
Inlet pressure
Up to max. 120 bar (1740 psig)
Differential Pressure
Up to 250 bar (3625 psig) · special models also available for higher pressure differentials
The values listed are maximum values and must not coincide under certain circumstances.
Pump Sizes
From 22/22 (4.7 cm3/U - 10 kg/h) up to 280/280 (12000 cm3/U). Intermediate sizes, with narrower gear wheels for higher differential pressure, are possible, e.g. 140/90 (690 cm3/U).

Polymers
PS · PET · PVC · PC · PA · PMMA · HDPE · LDPE · LLDPE · PP · Polysulphones · PEEK
Food industry
Liquorice · chewing gum
Viscoseal (VS)
The viscoseal is the standard seal for WITTE EXTRU and BOOSTER pumps. This is a dynamic seal for high viscosities and suction pressures. It can be provided with heating or cooling. The dynamic seal is suitable for high pressures and temperatures. Its range of use is limited by the suction pressure and the viscosity of the medium being conveyed (at least 10 Pas). The viscosity can be increased by an additional cooling system if necessary.
max. temperature: 450°C (850°F)
Viscosity: 10000 to 40000000 mPas (cP)
Stuffing Box
The stuffing box is a simple (static) seal for WITTE gear pumps. It can be provided with buffering if so desired. The range of application is similar to that of the viscoseal. The standard material used for the packing rings is made of expanded pure graphite with structural textile fibes. But it goes without saying, that other materials are also available.
max. temperature: 350°C (660 °F)
Viscosity: up to 40000000 mPas (cP)