Screen tube well construction

What is a screen tube well?

A screen tube well, or a tube well, is a well solution implemented in soil. In tube wells, the water infiltrates to the well from the screens in its walls. Screen tube wells suit better in various soil conditions than shaft wells as the length of the screen can be adjusted based on the thickness of the soil layer with higher hydraulic conductivity to ensure the maximal yield from the well.

Structure of a screen tube well.

Screen tube well types and sizes

In the tube wells, we use FLUXSCREEN screen tubes that we have patented and that have been used for decades. They are the most used screen tube solution in Finland and the plastic used in them has been tested and certified for use in food industry by VTT.

There are three types of FLUXSCREEN screen tubes:

All FLUXSCREEN screen tubes have V-shaped slits that have larger opening points inwards. The slits stay open and usable even in long-term pumping.

Different sizes and types of our FLUXSCREEN screen tubes.

The yield of the screen tube wells and the yield guarantee

FLUXSCREEN screen tubes with large slit area and the use of modern machinery enable the implementation of high-yield wells. The tube wells are suitable to ensure the water supply of both large cities and small water services co-operatives. Our highest-yield well has so far has the yield of 18 000 cubic meters per day.

With our well location surveys, we can determine the yield of the well already before the construction of the well, and we give a yield guarantee for the determined yield. The yield guarantee means that we can implement a screen tube well to the location we have investigated with the yield we have guaranteed. The yield of the well means the momentary yield from the well, that depends on the soil types around the well. The long-term yield is dependent on the water yield of the aquifer, and it is typically assessed with test pumping. If the yield we have guaranteed is not fulfilled, the well is not charged to the customer. This ensures our customers that the outcome of their investment is predictable and the risks are minimized.

Flushing a well.

Dimensioning and testing of screen tube wells

The screen tube is dimensioned during the well drilling process based on the soil types noticed. The dimensioning aims to ensure that the well has a long-term maximum yield and to prevent sand from drifting to the well. Moreover, the dimensioning ensures that the screen is not installed to soil layers that do not supply water and that can cause opacity to the water.

The tube well is tested during the implementation process. The test pumping of the well is used for measuring the yield of the well. The results of the test pumping are written on the well card. We have developed a technique for measuring well yield and following the changes in it during the use of the well over the years. We have long experience in measuring the well yield since 1979.

Installing a short screen tube well.

Modern, efficient and powerful drilling machinery for Finnish soil types

Our company has long traditions in developing well drilling machinery. Our newest heavy hydraulic machine was completed in 2010, and it has enabled drilling deep tube wells also in demanding soil conditions. The machine weighs 34 tons and has a drilling power of 180 kW.

Modern drilling machine.