Wellpoint Pumps

What is wellpoint dewatering?
Wellpoint dewatering is the most economical and widely employed dewatering system, especially where the water table does not have to be lowered too much (4,00 m - 4,50 m), although it is possible to achieve larger lowerings through special devices.

The most important elements of the system are vacuum and slotted screen: i.e. the wellpoint. Disposable wellpoints and compact resistant reusable wellpoints are in common use throughout the world. Each type of wellpoint has commercial advantages and disadvantages. In Latvia, the resistant reusable weelpoints are being used in most cases.

The wellpoint is made up of a piercing tip at one end and a series of metallic or plastic filters. It is being made in order to deliver the maximum quantity of water per unit time without removing the solid particles. This result has been achieved by accurately balancing the areas of the pipe and their interspaces. The external perforated shell allows less water to flow than the internal shell which is provided with a textile. This difference causes a drop in the pressure between the two walls. The pressure reduction on the internal filter and on the sand which is contained between the external mesh and the internal filter will determine a low inflow speed which will be maintainedconstant during the pumping. In this manner the water filtrates through the fluid bed of highly filtering sand.