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FEATURE
Types of pumps
• Velocity pumps: Rotodynamic pumps (or dynamic
pumps) are a type of velocity pump in which kinetic
energy is added to the fluid by increasing the flow velocity.
This increase in energy is converted to a gain in potential
energy (pressure) when the velocity is reduced prior to or
as the flow exits the pump into the discharge pipe.
• Positive displacement pumps: The positive
displacement principle applies in these pumps:
○ Rotary lobe pump
○ Progressive cavity pump
○ Rotary gear pump
○ Piston pump
○ Diaphragm pump
○ Screw pump
○ Gear pump
○ Hydraulic pump.
• Impulse pumps: A device for forcing running water
to a higher level by using the kinetic energy of flow;
the flow of water in the supply pipeline is periodically
stopped so that a small portion of water is lifted by
the velocity head of a larger portion. Also known as a
hydraulic pump.
• Gravity pumps: A pump deals more with differences
in pressure than with gravity itself. At ground level, the
pressure is said to be atmospheric pressure (about
10^5 pascals). A pump sucks some air from a pipe,
with a piston reducing the pressure inside the pipe (less
than the standard atmosphere).
• Buoyancy pumps: The basic principle of buoyant energy
(buoyant hydraulic energy storage system) is based on the
well-established technology behind pumped hydro-energy
storage plants. The major difference is the arrangement
and location of reservoirs at such plants.
One of the leading pump hire companies in Southern
Africa, Ian Dickie, says it prides itself on its ability to adapt,
respond and provide tailored solutions to customer pumping
requirements, quickly, safely and efficiently. Ian Dickie’s
specialist Pump Hire Division offers a full range of both Low
and High Head pumps to clients requiring a fast and efficient
pump solution anywhere in Southern Africa.
Its range of general purpose and specialist prime assisted
centrifugal pumps are available in a variety of forms, with
diesel, petrol or hydraulic drive options, ensuring the most
effective pump solution for every requirement, in terms of:
• Comprehensive pump service, from technical advice to
full installation
• Demonstrations of equipment to show the capabilities
of its pumps
• Carrying out site surveys to advise customers on best
pumping solutions
• Offering technical advice
• Training client staff on how to use and maintain its
pumps if required
• Offering a comprehensive range of accessories and
fittings