SOVEMA Universelle Extra Deep Hand Pump

The Universelle Extra Deep Well Handpump is a reciprocating level action pump for deep wells. The pump functions by lifting water via a piston that is raised and lowered inside a cylinde. The piston (or plunger) is moved by a pump rod connected directly to the lever handle at the pump head. The increased length of the water column in deep boreholes requires more effort to draw water and the lever of the handle makes the operation easier. The function of the reciprocating pump is based on the principle that water flows from areas of high pressure to areas of low pressure. The reciprocating pump creates an area of sufficiently low pressure above the body of water, causing it to flow upward. The Universelle delivers discharge rate of 1000 liters per hour at 70m with a pace of 40 strokes per minute.

The Universelle has the following unique design features:

-Modified pistons which are placed every 3 meters and adapt to slightly non-vertical bore-holes and possible strain of rising pipes. The permanent self-centering which occurs between piston skirts and rising pipes improves hydraulic joint’s tightness thus increasing pump’s efficiency

-Cylinder free design that reduces mechanical wear inside the riser. The tightness between the pipe and the pistons is naturally ensured by the hydraulic natural seal which is ensured by each rod’s upward stroke.

-Pump is self-priming at all depths.

-Coupling a ‘single mobile pulley’ to a modular counterweight, to increase piston stroke and allow adjustment of the required pumping strength to decrease the effort applied by the user.

-Corrosion resistant materials for all parts which are directly in contact with water. Specifically:

Riser/ PVC cylinder;
Riser plastic couplings;
Rods and nuts in stainless steel;
Pistons and foot valve in PVC and ABS.

The Universelle Extra Deep Well Handpump was designed to be a “village level operation maintenance” (VLOM) pump. The installation and maintenance are carried out in the village without any hoisting or extraction system. Human strength is sufficient to pull out the 2” rising pipe during periodic maintenance.

The pump requires minimal maintenance. Its infrastructure includes pistons, which are self-centering and devoid of joints, thus suppressing all frictions inside the riser. The annual maintenance cost was validated by the Agence Française de Développement and is estimated to be <$52.00 USD (30000 CFA) (including spare parts). ^{Interview with representative}

A certified discharge rate of 1000 liters per hour at 70m with a pace of 40 strokes per minute.

No known hazards