MANUAL PUMP submersible (Monolift) 45m
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MANUAL PUMP submersible (Monolift)
Definition
Positive displacement pump that moves fluid by trapping a fixed volume between rotor and stator, forcing the fluid into the discharge pipe.
Performance:
- flow rates up to 12 l/min
- depths up to 100 meters
- direct drive head pumps: for boreholes up to 60 metre
- geared head: for boreholes up to 100 metre
Synonym
Positive displacement pump , progressive cavity pump, helical rotor pump or eccentric screw pump.
Specifications
Progressive cavity pump:
The water is raised by the rotation of an eccentric screw. The pump consists of a spiralling helical rotor (similar to a corkscrew), sitting tightly inside a rubber stator/sleeve. As the rotor turns inside the stator, it forms a set of fixed-shaped cavities that progress along the length of the stator and force the fluid inside to move along with them as they turn.
This type of pump is a very reliable hand pump. However, any maintenance task that requires removal of the rods and rotor assembly requires special lifting equipment.
Specifications:
- the flow rate depends on water level:
- at 25 metre : 16 l/min
- at 45 metre: 16 l/min
- at 60 metre: 9 l/min
- output is proportional to speed
- maintenance: difficult
- corrosion resistance: good
- abrasion resistance: good
Instructions for use
Before installing:
- the need to arrange maintenance and a supply of spare parts must be taken into account from the beginning
- before the pump is installed, the borehole should be cleaned, disinfected and protected
- the water used for priming must be free of contamination
- pumping sand will damage the pump and should be avoided
- to ensure proper installation and operation of a hand pump, proceed according to the instructions provided by the manufacturer
- for more information, refer to "Community Water Supply: The Handpump Option", UNDP & World Bank
- see also the preliminary remarks section
Main criteria to choose hand pumps:
- availability of pumps and spare parts; try to use models available in the region
- pump's type of use, i.e. use in family, small community, village, clinic...
- the depth of the well or borehole (an increasing length of the water column requires more effort to draw water as water is heavy)
- delivery head
- desired discharge rate
- quality of water (turbidity, corrosive matter...)
- price range of pump and spare parts
- ease of maintenance routine (are any special tools required, access to maintenance, e.g. replacing seals)
- ask your technical referent if you have any doubt in choosing and/or operating hand pumps