HI-TECH MELT PUMPS FOR EXTRUSION

ADVANTAGES OF MELT PUMPS

CONSTANT THROUGHPUT. Typically 0.1% stability when used with exclusive Harrel differential pressure controller.
CONSTANT EXTRUDATE DIMENSIONS. When combined with DIGISYNCH synchronization of haul-off speed, holds dimensions to very close tolerances.
LOWER MELT TEMPERATURE than with extruder used alone.
GREATER ENERGY EFFICIENCY. Total energy used by extruder + melt pump less than extruder used alone.
FREEDOM FROM PRESSURE CONSTRAINTS. Extruder screw can operate at pressure optimum for good mixing. Melt pump acts as a pressure transformer to raise or lower back pressure on screw.
BACKED BY HARREL'S 20 YEARS OF EXPERIENCE making precision melt pumps specifically designed for plastic extrusion.

STANDARD EXTRUSION MELT PUMP

Pressure to 10,000 PSI.
Extremely rugged
8 sizes from 0.14 cc/rev through 50 cc/rev.

PVC MELT PUMP

PVC runs great with a melt pump! Harrel developed a melt pump for PVC over 10 years ago; probably more PVC is used in Harrel melt pumps than any other polymer.

DESIGNED particularly for use with PVC.
NO DEGRADATION OF POLYMER in melt pump when used properly.

DUOSTREAM MELT PUMP

TWO SEPARATE METERING CHAMBERS and two sets of gears on single shaft.
GIVES TWO IDENTICAL STREAMS of plastic.
EFFECTIVELY DOUBLES output of line, where downstream equipment is limiting factor.
ALSO IDEAL FOR COEXTRUSION applications, where two layers need to be the same.

MELT PUMP UPGRADE SYSTEMS

COMPLETE SYSTEM FOR ADDING melt pump precision to existing lines. Includes:
- PRECISION HARREL MELT PUMP with pedestal support, if extruder cannot support weight.
- PRECISION GEAR REDUCER and drive motor, mounted on support stand. Double knuckle coupling accommodates shaft misalignment.
- DIFFERENTIAL PRESSURE CONTROLLER -- controls extruder speed to keep pressure across pump constant.
- DIGITAL SYNCHRONIZATION with puller speed optional -- gives one-button control.
- TEMPERATURE CONTROLLERS and power modules for control of temperature of melt pump and adapters

THE HARREL GEARTRUDER

PRECISION HARREL MELT PUMP mounted directly on rugged Harrel Extruder to form an integrated system.
HARREL DIGIPANEL CONTROLLER coordinates entire system.
MUCH EASIER TO REALIGN AFTER SCREW IS PULLED.
EXCLUSIVE HARREL DIFFERENTIAL PRESSURE CONTROL greatly increases throughput stability -- typically 0.1%.