Horizontal Collector Wells (HCW)
Horizontal collector wells are used to collect ground water from higher aquifers through drilled filter strings. A drilling machine was specially designed for this purpose by Anger’s. This horizontal drilling machine injects horizontal strings into ground water aquifers with a pushing force of up to 1500 kN. As a rule, several horizontal filter strings are produced from one vertical, impermeable shaft.
Vertical filter wells are not always suitable for all geological conditions, at least not from an economical point of view. Often aquifers are found in limited horizontal layers. In this case, several vertical filter wells would be needed to develop these thin, but productive deposits. Besides, these vertical wells pass through several layers of aquifers so that ground waters of different quality can get mixed.
A possible solution to these special demands can be the construction of a horizontal collector well, such as Anger’s has constructed for some years now.
The development and construction of a horizontal drilling machine has opened up a completely new field of activity to Anger’s. The special thing about our plant is this: the machine is powered entirely by water hydraulics. Consequently, no oil-substances are used and, thus, sensible ecosystems in the surroundings of aquifers are protected. Furthermore, the device is also a genuine innovation when it comes to occupational safety: there is no necessity to carry out works under hanging loads anymore.
Technical data of our horizontal drilling unit:
- pushing force up to 1500 kN at 160 bar
- horizontal filter strings at an angle of up to 360°
- filter strings can be arranged radially and at different layers of depth
- strings with a borehole diameter of up to 464 mm
- closed water-hydraulic cycle
- integrated crane-/ lift-system for handling of materials
HAS was already able to successfully carry out some initial projects with this self-developed horizontal drilling machine, for example the construction of a collector well in Munich. This string was drilled from an existing transition well as a substitute for a groundwater transition facility. Following the pushing method, the strings were completed using the gravel-pack method. Technical data of the strings:
- length of lateral hole 3 m
- screen diamter DN 200
- Drill pipe diameter 464 mm (Da)
At the moment the horizontal drilling machine operates in Oberhausen, where a HCW is constructed in immediate vicinity to housing in order to lower the ground water. Planned data of the HCW:
- Shaft with a diameter of 3370 mm and a depth of approx. 12 m
- Four planned strings at 80 m each with a drilling diameter of 464 mm (Da)
- Subsequently, completion with gravel-pack method and a screen diameter of DN 200