The best way to provide access to spring water is to have an aquifer at home. But his work also involves the need to replace pipes or clean them. Drilling an aquifer on a site is relevant in many country houses. But with the source, problems can arise both during drilling and during operation. What if the casing needs to be replaced or completely moved? How to pull a pipe out of the well with your own hands? This is one of the most difficult issues facing land owners.
There are various reasons to remove an old casing, and there are several methods for this.
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How is the problem solved in practice?
An aquifer resembles an ordinary small-diameter well, but its depth is many times greater. For the full functioning of the “water race”, its walls must be protected from soil displacement. To this end, they hammer in a drilled hole casing, and operational ones are inserted inside, so that spring water is always clean.
Accordingly, the diameter of the inner pipe is slightly narrower than the casing section. The best option is the use of double pipes, which is more economical. At the same time, they strengthen the soil, and do not allow ground sediment to come into contact with spring water, ensuring its purity.
Drilling a water well is a time-consuming process, and over time the casing becomes unusable and needs to be replaced. It is also possible:
- depletion of the spring;
- pipe corrosion;
- change in the chemical composition of water;
- the collapse of the walls of the mine.
Attention! Pulling steel pipes out of the well is quite possible. Asbestos-cement products are also used for wells in a suburban area, but they become fragile over time. It is almost never possible to get complete such columns.
Few are aware:
- how deep the horizon reaches the pipe;
- what processes occur in the aquatic environment;
- what is the degree of deterioration of the production and casing string and how to determine it.
It is easy to remove a steel or plastic pipe, but asbestos-cement casing can break during work
Well operation is also full of unexpected situations, including the ingress of foreign objects into it that can only be removed with casing. This time-consuming task involves additional material costs. If the question arose - how to remove the casing from the well, it is important to know what material it is made of. Steel - the most reliable and durable. Lightweight plastic and polymer are much more economical than steel and stronger than asbestos-cement products, therefore they occupy an average commodity position in their niche.
Common reasons for replacing casing:
- damage or corrosion;
- clogging of the well or reduction of its clearance;
- high degree of equipment wear.
It is desirable to break down the whole process into stages. A well is prepared for pipe extraction by removing surface water supply equipment.
How to extract an external pipe from a used well?
Without special devices and equipment that is traditionally used to pull out the outer (casing) pipe, this issue is indispensable. From deep wells, fragments of a cylindrical shape can be obtained using the so-called “pipes”. A winch and heavy lifting jacks may also be needed. Still needed flooring for the support, consisting of beams, rails or metal bars.
To extract the pipe, lifting equipment, for example, a winch, is required
When working with a jack, it is important to prepare the wellhead in advance in order to provide access and convenience in pipe extraction. The simplest way to retrieve damaged items involves using:
- metal clamps.
- swivel plugs;
- metal bars;
- welding machine;
- jack.
Hydraulic equipment with a jack is mounted above the prepared wellhead. Then the tool for gripping the pipe is installed by attaching special clamps. When the grip is organized correctly, it is not difficult to remove the casing using a jack. The remainder of the pipe, which does not need to be removed, can be cut in place by a welding machine. The extracted parts are stored in a previously prepared place, from where they are easy to ship and export.
Note! In order to simplify the extraction of equipment fragments, it is advisable to think over this process at the stage of laying the well. Before you remove the casing from the well or remove fragments of damaged equipment, it is important to measure the depth of the well.
What is a fishing tool?
Emergency work to remove stuck fragments of rusted pipes, a pump, large objects at the bottom of a deep and narrow well, a well or an abandoned column is carried out with 2 types of fishing tools:
- mortise bells for external capture;
- threaded tubes.
When eliminating accidents in wells, a fishing tool is used, one of which is a bell
You can get the old pipe from the well in parts or in whole. But at the same time, it is taken into account that a fracture of the formation, vertical displacement of the well or seasonal violation of the water circulation inside it is possible, which complicates the excavation of casing strings.
Fishing bells (tubes) are through and through. The specificity of the through bell implies the passage through its base of the extracted damaged fragment. Further, external equipment (threaded couplings) carry out a notch to get an extractable riser. External pipes are pulled out also by means of taps.
The tubes have a different design:
- collet type;
- sleeve and die;
- combined.
It is possible to use fishing milling cutters to lift up fragments stuck in an inclined well. This equipment allows capturing by tapping into a retrievable pipe. If fragments of the column are jammed, they are removed from the wells by means of hydraulic jars that create vibrating shocks. Such a tool is most often used by professionals from specialized companies.
Flushing method
Before attempting to pull the pipe out of the well, it is important to assess the amount of damage. Keep in mind that clogging a well and gradually destroying equipment is a normal process. A sediment forms at the bottom, and the casing rusts and gradually falls apart, since its surface is covered with cracks and splits. The chemical composition of the soil also matters - a too acidic environment is more destructive than neutral or alkaline.
If the casing is made of metal, then it will collapse under the influence of natural factors and it will be necessary to think about replacing it in a short time
Depending on the degree of neglect of the well, one of the methods that determine the scope of work is chosen:
- seating and flushing the entire riser;
- tension and replacement of structural parts;
- dismantling of casing and production pipes.
Tension is associated with the use of a hoist or winch to pry the pipe over the upper edge and pull it to a break. This part is taken out of the well, after which other fragments of the column are picked up by fishing equipment. It is important to work so that the fragile parts of the pipe do not get stuck in the well opening. It is best to use a hydraulic jack. Such equipment is not always effective, especially if the mine is drilled at an angle or formation displacement has occurred. The wide pipes and the considerable depth of the well also make it difficult to extract damaged fragments. The casing is often removed from such a well after flushing the water system with a pump and specialized equipment.
The column is connected to the pump and flushing equipment, starting work under minimal pressure, after which the pump load and the volume of water supply are gradually increased.
Attention! Removing fragments of the column is also possible in other ways, for example, by immersing a threaded tool that, when rotated counterclockwise, paces the column and rotates it until the extraction is completed.
Is it always appropriate to extract casing from an old well?
Extraction of a narrow casing from an old well with great depth requires great efforts and experience. When deciding whether to remove pipes, flush or drill a new well, it is important to consider:
- terms of use of the well;
- construction material;
- degree of pollution;
- reasons for dismantling;
- affordable fishing tools;
- depth of immersion equipment.
Lifting a pipe from a well is a laborious and costly process that is not always justified
In some cases, it is theoretically possible to decide how to get the pipe out of the well, but in practice this is not always possible. For example, if heavy worn equipment at a significant depth - with a noticeable vertical shift of the well. Winch breakage or loss of equipment at great depths occurs with an incorrect assessment of the scope of work. A specialist in this field always assesses the degree of risk in order to decide whether it is worth doing it at all.
Sometimes the question is solved in another way - it is easier to insert a smaller diameter product into a wide production pipe. Then the external riser will act as a casing string, and the collapsing base will become an additional barrier between the soil and the pipeline.
Even if the inspection of the well will be done by hand, expert advice is always helpful, which will evaluate the scope of work and the degree of risk. Dismantling the old structure is not always required, especially when it is obvious that it will fall to pieces when removed. Often the costs are not justified, and it is easier to make a new well.
