GEHO® DHC
This GEHO® DHC pump is an industrial design hydraulically
driven piston pump capable of handling extremly viscous slurries,
sludge and paste, both organic and mineral, on a 24/7 operational
basis. These pumps have excellent suction capabilities, are
designed to handle large objects and to minimize wear. The DHC
pump range is developed and manufactured by Weir Minerals
Netherlands b.v.
Features / Benefits
- capacities up to 150 m3/h
- pressures up to 120 bar
- high viscosities up to 50.000 cP (mPas)
- moderate to high abrasiveness
- mild corrosiveness
- up to 50 mm particle size
- up to 90% solids content
Where slurry consistency and particle size are beyond the handling
capability of a crankshaft driven pump, consideration is given to
hydraulically driven piston pumps. These are two cylinder,
single-acting pumps with continuous water flush on the backside of
the piston. These pumps are designed with a prerequisite low stroke
rate, a low piston velocity and large flow areas, which also help
to minimize wear. Cartridge mounted sensors are provided at either
end of the hydraulic drive cylinders. Signals from opposed
sensors/pistons enable a plc controlled stroke reversal and either
piston to complete a full stroke. This method of leakage
compensation enables the use of standard hydraulic piston seals,
which afford a 5 to 100% capacity adjustment range.
Larger size pumps use a linear transducer in lieu of sensors. It
reduces the length and weight of the piston and cylinder and
enables a full stroke length independent of the stroke rate. The
drive cylinder design, oil hydraulic flow sheet and plc programming
aim to obtain a relatively smooth piston reversal and reduce
hydraulically and mechanically induced loads. The larger size pumps
accomplish piston pump stroke reversal by reversing the swash plate
angle of the main oil pump(s) in lieu of manipulating a control
valve. A detailed review of the slurry consistency, performance
indicators and project requirements determines the choice for
either of the two available piston pump models.
DHC - Piston pump with actuator assisted valves
The model DHC piston pump is fitted with large diameter, high lift,
actuator assisted suction and discharge valves and handles rather
viscous pastes and particles typically not larger than 50 mm. It
uses the valve design from the diaphragm pump, except that the
valve cone bolts directly onto the actuator rod. The actuator load
and activation sequence is arranged such that a valve will not open
against the pump discharge pressure. As a result the system is
inherently protected against backflow, even if a valve is jammed
open.
