Downhole pipes. Well pipes

Comfortable conditions living in summer cottages is living with all amenities, including constant access to water, which is impossible without the use of specialized wells for water. The well construction process involves the use of casing pipes. The main purpose of their application is to prevent the collapse of the well wall.

When ordering drilling, everyone asks such a question as the choice of casing for their well. And at these moments, many companies come up with their proposals. But you should always remember that the choice of a suitable casing pipe for you is carried out depending on the specifics of your area, key features soil, well depth, width according to your project. And the calculations directly depend on the number household appliances which is powered by water washing machine, Dishwasher, then a kitchen, a bathroom, a bathroom, whether water is required for watering the site - all this is taken into account. For all pipes used in well drilling, there are certain characteristics. When choosing, you should follow correct form, wall size, thickness and diameter, it is very important that they do not go beyond the norm. Our company uses specialized, high-quality casing pipes, which are necessary for high-quality well construction. You can choose for yourself a steel version, anodized, metal-plastic, plastic. In order for the choice of casing to suit you, it is better to familiarize yourself with the existing options and their features:

Steel pipes

One affordable option that has excellent performance is steel pipes. Steel pipes have been used in well drilling for a long time. They are known for their reliability and durability. A steel pipe with a wall thickness of about 5 mm can last more than 40 years without any complaints. In some cases, well drilling is only possible using steel products. According to the manufacturing method, they are divided into electric-welded (seam) and seamless (seamless).

Seamless ones are obtained by punching a hole in hot solid steel billets. A seamless pipe is stronger than an electric-welded pipe, but in relation to well casing, this difference does not play a special role. Seamless seamless steel pipe perfectly withstands ground pressure, the estimated service life of such a pipe will be an interval of more than 50 years. On such pipes with a wall thickness of 4.5 mm, high-quality connecting threads are perfectly cut, due to the homogeneity of the material, galvanic couples are not formed. You can list the pros for a long time, if not for one minus - the cost.

Anodized pipes are produced according to the manufacturing technology of thinner-walled pipes than other pipes. The best anti-corrosion property of these pipes appears when the surface is protected with zinc. It would seem that a very good option - the pipe does not rust, it lasts longer in the well ... If it were not for a few disadvantages, it is impossible to cut a high-quality conical thread for connection on such a pipe with a thin wall. When connecting by welding, zinc burns out at the junction, exposing the metal. Salt battery has simple design- a zinc cup is taken, filled with a saline solution, into which a carbon electrode is lowered. During operation, the glass is destroyed. An almost absolute analogue is obtained with a galvanized column in the well. One element of the galvanic couple is an open metal in the areas of a threaded or welded joint, the other is zinc protective covering. Zinc compounds get into the water, which, when taken from a well, is most often used for drinking purposes ...

Reinforced pipes are a kind of hybrid of a metal electric-welded pipe with a wall of 4 mm and a solid-drawn pipe with a wall of 5 mm, which is called reinforced casing. It looks like an ordinary electric welded pipe, but threaded ends from a seamless pipe are welded to it. This eliminated the problem with a weak weld on the thread. Our company produces steel casing pipes with reinforced threaded tips. The innovative design combines high strength seamless and low price seam pipe. The most critical parts of the casing pipe are located at the ends, where the powerful torque of the drilling rig is applied to the threaded connections and maximum strength is required.

metal-plastic pipes, which are obtained using the technical process of coating a reinforced pipe with a protective anti-corrosion polymer coated. The technological process consists of two stages: at the first stage, the metal pipe is cleaned on a machine in automatic mode, where rust, dirt, oxide layer are removed, and the surface required in terms of roughness is created. Next, hardening is created, which seals the upper layer of metal, and thereby, to some extent, creates its own, metal-sealed surface that prevents corrosion. At the second stage: the already cleaned, degreased, prepared pipe enters the line, where it is first heated in the inductor to a temperature of 180 degrees, and then the extruder applies adhesion - an adhesive composition in an annular manner. Then polyethylene pipes are sent for cooling.

Pipes made of HDPE or PVC-U

PVC-U is a pipe made of unplasticized polyvinyl chloride. They have a margin of safety several times greater than HDPE and are able to withstand a load of more than 5 tons. uPVC is a rigid material and in the calculations of "hydraulics", according to the designers, it is very close to metal. They cost more than HDPE pipes. The service life of uPVC wells is only limited natural conditions and human factor, such as: depletion of the source, decrease in production rate, or complete drainage of limestone. Modern consumers choose pipes from more modern materials resistant to various influences, due to which, in terms of "price / quality", uPVC is in the lead. The durability of a PVC-U column under the manufacturer's warranty is 50 years. But, theoretically, life cycle uPVC products without reducing the physical properties can be 6 times more.

This article discusses the positive and negative aspects of the properties of pipes from various materials, as well as the main points that affect their choice when constructing a well. In any case, which pipe to choose - the decision is yours. But we really hope that the information we have provided will undoubtedly help you make the right decision, which is right for you, when choosing materials for casing. I wish you success!

Well drilling is a complex technological process that involves the use of additional Supplies. One of the cost items is the casing pipe. When it comes to material selection, there is a balance between quality and material price. Which casing pipe is better and more practical to use? The difference and selection criteria will be discussed in the article.

What is a casing pipe

Casing pipe is used in drilled wells. The wellbore passes through various layers of soil. Most of them are loose, so without proper care, the well will quickly become unusable. The purpose of the casing is to fix and hold the walls in their original state. This also applies to those moments when the displacement of the soil occurs. Separate sections of the casing pipe are firmly connected to each other. At the same time, they must form a sealed structure that will not allow rain or other water to enter the well. In addition, the casing pipe is able to raise the water table so that the pump does not lower to the bottom of the well. Due to the purpose of the casing pipe, it must have the following qualities:

• high strength;
• pressure resistance;
• resistance to corrosion.

These characteristics correspond to pipes that are made of iron, stainless steel and some types of plastic, asbestos-cement pipes are also used. The casing pipe must have a minimum diameter that the pump can fit in, in most cases it starts at 110 mm.

Metal variant

This option is one of the most common and used. Previously, cast iron casing pipes were used. If you choose a product with a wall thickness of 6 mm, you can be sure that the well will last up to 50 years or more without any problems. In this case, the pipes will not lose their strength and will not have a negative effect on water quality. In modern practice, steel pipes are used. They can be called environmentally friendly. Water, when interacting with metal, does not form harmful chemical compounds that could harm human health. During prolonged use, rust may appear in the water, but it does not dissolve and is therefore easily removed with a conventional fine filter.

The round shape of the steel nozzle provides it with excellent mechanical strength. It easily supports the weight of the entire structure, as well as the mounted pump. Steel will protect the well when the soil layers are shifted in a small range. A well that has such a casing string is perfectly cleaned by pressure washing. In case of large silting, a drilling mechanism can be used to deepen. Metal columns are great for artesian wells, which can be drilled to a depth of over a hundred meters.

The main disadvantage that stops many from using this type of casing is its high cost. With a sufficient budget, it is better to choose this option, if it is limited, then it is worth weighing all the indicators and considering if there are more profitable option. Pipes that are made without a seam have greater strength. They are harder to bend and last longer. These are often used for the construction of gas pipelines.

Corrosion resistant pipes

Installing stainless pipes as casing is an excellent option. There are two types of such products: galvanized steel and stainless steel. Each has its own advantages and disadvantages. But it is worth thinking about the appropriateness of their use. If the service life of an artesian well is on average 50 years, and ordinary metal pipes can serve the same amount, then is it worth investing unreasonably additional funds. Galvanized pipes are a poor candidate for this application. The reason lies in the zinc itself. If you pay attention to galvanized roofs, then over time they become rusty due to exposure to sedimentary moisture. The same situation awaits branch pipes in the casing string. But at the same time, harmful components will get into the water, which will adversely affect health.

Some experts suggest using enamel coated casing. The same is true for some types of dishes. It really protects the surface perfectly and has no negative effect on the body. But everyone has seen what happens to an enamel pot if it is accidentally dropped. The enamel is chipped and the place under it begins to rust. Since nozzles in the well can experience an impact that is several times greater than the force of a normal fall, the feasibility of such a solution should be seriously considered. The destruction of an enameled pipe occurs faster than a conventional metal one. This is due to the fact that the thickness of the metal in such pipes is less.

Advice! Given the above information, you should not follow the lead of marketers and overpay for something that cannot be fully used.

Is asbestos cement good

Another option that is widely used for casing wells and wells is asbestos cement pipe. Not every drilling company will decide to use such material, because it has some features that not everyone knows how to work with. The cost of such a casing string is somewhat lower than that of a metal one. The advantages include the environmental friendliness of the material. Asbestos cement does not react with impurities that may be contained in water, which means that no emissions occur. harmful substances. It is widely believed that asbestos cement stimulates growth cancer cells, but this has not been proven in studies. With pressure, a small part of the fibers can really be lifted, but if a cleaning filter is installed, then they will remain in it.

The disadvantage of asbestos-cement pipes is their mechanical instability. With strong compression or impact, they can lose their strength and tightness. Unlike metal pipes, when using asbestos-cement pipes, it is impossible to make an additional deepening after some time. For asbestos-cement pipes, a well with a larger diameter will be required than for metal pipes. This is due to the design of the pipe. For its stability it is necessary to make thick walls. Pipes of this type are suitable only for limestone wells, while its depth should not exceed one hundred meters. The disadvantages of the material include poor sealing of the seams. This is due to the absence of any fixing elements, except for the expansion of the neck.

Note! Concrete is a porous material. Various debris and silt can clog into the pores, which is almost impossible to clean out from there.

Can plastic be used

Many well drilling companies like to use plastic casing pipes. The basis for such pipes can be low-pressure polyethylene, unplasticized PVC and polypropylene. The service life of such pipes can reach hundreds of years. Polymers do not interact with well water, therefore they do not decompose and do not corrode. The bacteria found in the soil are also unable to decompose plastic into short time. The listed types of polymers do not release any substances into the water, so there is no danger to health. But this is only on condition that the pipes are purchased from a responsible manufacturer. Delivery and installation of pipes made of polymers are much easier than metal counterparts.

The limitation on the use of plastic casing pipes is the maximum depth of the well. Products are suitable for a maximum sand well, which does not exceed 60 meters. Plastic also does not tolerate low temperatures well. It becomes brittle and can be easily damaged. A plastic casing can be installed if it is known that the area is free of heavy ground movement.

Combined options

For some types of wells, combined casing strings are used. The essence of this design is that the main casing is carried out using a metal pipe, and a plastic one is laid inside. The advantage of this solution is the minimum amount of rust in the water. Extends the service life of the metal pipe. In addition, the plastic casing can be replaced if required. It is allowed to deepen the well when dismantling the plastic component. A video of the installation of the casing is below.

Conclusion

As you can see, the choice of material for the casing should be approached very carefully. This will protect the health of your family. In addition, high-quality casing has a positive effect on the life of the well. Wells with good casing are easy to maintain.

When planning the organization of an independent water supply at home, it is necessary to study the technology and the nuances of creating a well. One of key points arrangement of an autonomous water supply - the choice of casing.

The wellbore performs diverse tasks and largely determines the durability, uninterrupted operation autonomous system water supply. Agree, having invested a lot of money and effort in the construction of a well, the last thing you want to do is fix the problems associated with the poor quality of water intake.

Therefore, at the design stage, it is necessary to approach the selection of the casing string with all responsibility. We will tell you which pipes are best for the well, what material and type of connection of the wellbore segments is preferable to use in a given situation. The knowledge gained will save you from buying the wrong product.

The arrangement of an individual source of drinking water is a costly and time-consuming process. Investing in, each owner suburban area or a private house expects a long-term result.

Service life, well head and qualitative composition The produced water largely depends on the characteristics of the pipes used to create the casing string.

When drilling in the thickness of the soil, a channel is formed, where pumping equipment is subsequently placed. To ensure the isolation of the vertical shaft from earth's crust, casing pipes are immersed in the well. The gap between the earth and the walls of the channel is filled with concrete or gravel-sand mixture

The water-lifting pipeline solves a number of important tasks:

• protects trench walls from collapse into the well space;
• ensures well integrity under pressure and ground movements;
• prevents pollution– ingress of untreated sewage and ground water(top water) into the trunk;
• prevents silting wells.

When drilling in one pipe, the casing string is also operational - it accumulates water from the aquifer, which the pump transports upwards.

Generally, drilling a well personal plot, if it is intended exclusively for irrigation and other household needs, it is performed in one column. For drinking water supply, the trunk includes two pipes: a casing and a carrier filter.

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Therefore, high requirements are put forward for the quality and material of the pipes used:

• high strength and resistance to deformation during the entire period of operation (about 20 years);
• complete tightness walls and joints;
• resistance to corrosion and negative impact chemically active elements;
• environmental friendliness- the material should not affect the composition of the produced water;
• straightness production column.

For standard applications, distortion along the length of the casing pipe within 0.7 mm per linear meter is acceptable.

Evenness deviation threshold for a high-precision channel: 0.5 mm - with a pipe diameter in the range of 108-146 mm, 0.3 mm - for pipes with a diameter of 33.5-89 mm. The data are given per 1 m.p.

Casing Selection Options

There is no single true standard for drilling. The method is determined on an individual basis.

Many indicators are taken into account: the structure of the soil, the height of groundwater and aquifers, water quality, the diameter and depth of drilling.

Well design is best entrusted to a specialized company. Employees will compare all the parameters, offer the optimal design, calculate the flow rate of the well, taking into account the static and dynamic water levels (+)

Any drilling company will offer its own version of the project and recommend, in their opinion, the best type of pipe. The final decision on the choice of casing string is made by the customer.

The performing organization, first of all, defends its own interests, so their decision is not always objective. Some contractors specialize in any one type of downhole system device and try to "impose" a profitable option for them.

Only the right decision- decide in advance which pipe to choose and use for the well, comparing all the pros and cons, and after that - apply for the development and implementation of the project.

When making a decision, you should take into account the main parameters for choosing a riser pipe:

1. Manufacturing material. This parameter determines the budget for installation work, the bearing capacity for reservoir loads, maintainability and longevity of the well.
2. The method of joining the elements of the column. The choice of method depends on the pipeline material, drilling depth and casing diameter. In any case, the connection must be completely sealed, otherwise the water quality will deteriorate over time, and the pump and the well as a whole will fail.
3. The calculation of the value is made taking into account the maximum possible water consumption per day.

The larger the diameter of the supply pipeline, the higher the productivity of the well.

Types of materials and their characteristics

Borehole pipes are produced from metal, asbestos cement or plastic. Very rarely used in the organization of water intake wooden crafts– they are absolutely environmentally friendly, but despite protective treatment susceptible to soil moisture and prone to deformation.

View # 1 - the strength and durability of the metal

Metal supply pipes are available in two versions:

• cast iron;
• steel, which can be enamelled, galvanized, made of stainless steel.

Very rarely, cast-iron analogues are used for casing. Among the metal counterparts, these pipes are the most affordable, but the material is very fragile and heavy.

Many companies refuse to work with cast iron because of the complexity of installation. In addition, it is impossible to guarantee the safety and tightness of the pipe - when the soil layer moves, the metal can crack

Steel is a traditional casing material that has been proven for decades. Steel almost 100% meets the requirements for downhole pipes.

Products made of ferrous metal adequately withstand tests in wells of different depths, regardless of the type of soil.

The standard wall thickness is 5-6 mm, the service life is about 50 years. Durability is determined by the corrosion rate of the steel sheet - 0.1 mm per year

• structural rigidity– the material is equally good for small wells (50 m) and for deep drilling (up to 300 m);
• precise axial alignment assembly and reliability of pipe joints;
• material stability- in contact with water, steel does not emit harmful substances;
• serviceability– due to the mechanical strength and resistance to vibration in the installed casing string, cleaning of the borehole channel, re-drilling in case of silting or clogging is acceptable.

The main disadvantage of the steel line is the high cost of the material. Manufacturers of cheaper analogues, extolling their products, appeal to another disadvantage of steel - the formation of rust.

There is an opinion that the pollution that has appeared worsens the quality of water and increases the content of iron in it. However, this is shown to be a myth.

Rust is insoluble in water. Particles of oxidized metal are able to delay even household filter. A possible nuisance due to rust is a breakdown of pumping equipment designed to run clean water

Rolled metal with corrosion protection is more expensive than conventional steel pipes, but the technical and operational features of the materials cast doubt on the expediency of overpaying.

The coating prevents corrosion, but it is very fragile and it is unlikely that it will be possible to avoid damage during casing. The places of chipping and microcracks in the enamel are the points of appearance of rust.

In the process of destruction, through corrosion can form in the damaged area, since metal of a smaller thickness is used in the production of enameled pipes.

The enamelled pipeline meets all sanitary and hygienic standards and does not change palatability water. The disadvantage of the material is the impossibility of a full cleaning of the line due to the fragility of the enamel

Galvanized pipeline. With regular contact with water, zinc oxide is formed on the walls of the pipe - a substance hazardous to health. The use of galvanizing is permissible only during the construction of a technical well.

The standard thickness of a galvanized pipe is 2-2.5 mm - this is not always enough to ensure structural rigidity. Such a highway is subject to deformation due to ground movements.

Stainless steel. The material has all the advantages of rolled steel and even higher cost. Stainless steel is distinguished by the presence of anti-corrosion resistance, which has a positive effect on its period of operation.

Is it worth buying stainless steel if the service life of a high-yielding well is equal to the service life of a steel pipe? It is necessary to build on financial capabilities and the purpose of the well

The installation of a metal line is economically justified when arranging a deep artesian well, designed for regular use.

"Surface" sand channels for seasonal use should be made from more accessible materials.

View # 2 - corrosion resistance of asbestos cement

Asbestos-cement pipes, which have been used in the organization of wastewater disposal for more than 70 years, have also been tested for years.

The material is characterized by some positive qualities:

• asbestos cement is absolutely not subject to corrosion;
• neutral composition of the material - the components do not enter into chemical reactions;
• unlimited service life - more than 60-70 years;
• low cost.

Despite significant advantages, asbestos-cement elements are rarely used today in the development of a "water source".

The main disadvantage of asbestos cement is brittleness. In order to strengthen the walls of the pipe, they make it thicker, which increases the weight of the product and forces you to dig a well of a larger diameter.

The negative aspects of asbestos cement include:

1. Installation difficulties. Installing a fragile line requires highly qualified performers. The work is carried out with the help of lifting equipment.
2. No thread. The sections of the line are interconnected end-to-end - it is problematic to achieve complete tightness of the fixation points without threads.
3. Questionable security. There is a theory that asbestos fibers contain chrysotile - a source carcinogens that adversely affect health. However, this assertion has not been proven in practice.
4. Difficult cleaning. Concrete is a porous material in which dirt accumulates in microcracks. To perform high-quality cleaning of the walls of the casing string, the well will have to be completely drained.

After installing the asbestos-cement casing string, subsequent drilling operations in the well are excluded.

The technical characteristics of the material do not allow the use of asbestos-cement pipes for a "sandy" source. Such casing is applicable for artesian wells with a depth of no more than 100 m.

Type #3 - durable and affordable plastic

Relatively recently, the market for casing products has replenished with plastic pipes. Modern technologies made a worthy competition to traditional steel pipes.

Comparative advantages of elements made of polymers:

• immunity to water - even with constant contact with a humid environment, corrosion does not form on the plastic;
• retain their structure for a long time and do not collapse;
• do not affect the composition of drinking water;
• the material does not provoke the development of pathogens;
• ease of installation and transportation due to low weight;
• it is possible to use a threaded connection to assemble the column, which ensures absolute tightness of the joints;
• economy - a well with plastic pipes will cost an order of magnitude cheaper than metal or asbestos-cement casing.

The estimated service life of a polymer water line is about 50 years. This theory is based on the corrosive inertness of the material.

The main disadvantage of plastic is low strength. That's why, polymer pipes it is permissible to install only in single-pipe wells, not exceeding a depth of 50 m, or in two-pipe wells as an internal casing

An additional argument against the use of plastic elements is sensitivity to temperature extremes and mechanical stress. Plastic casing will not withstand ground movements and is deformed in severe frosts.

Polymeric water intake pipes are made of different types raw materials: unplasticized polyvinyl chloride (UPVC), frost-resistant polypropylene (MPP) and low-pressure polyethylene (HDPE).

As a rule, the plastic production pipe passes through the limestone and deepens into the aquifers. Thus, the steel does not come into contact with the feed drinking water. The disadvantage of the "double" highway - an increase in the cost of the project

Which column assembly option is better?

A set of requirements for casing pipes and technologies for connecting well string segments is displayed in GOST 632-80. The regulation allows the use different methods assemblies.

Based on the docking method, the appropriate type of pipe is selected, so this issue must be resolved at the well design stage.

No. 1 - one-piece contact of pipes for welding

Welding provides the most rigid connection of metal pipes. The main advantage of the method is now being questioned by representatives of a number of drilling companies.

Arguments against using welding:

• the probability of insufficient tightness of the weld;
• the possibility of deflecting the pipe along the vertical axis, which makes it difficult to install the string in the well;
• insufficient corrosion protection of the seam.

However, with a high level of professionalism of the welder, there will be no listed defects. Majority building structures(bridges, farms, oil pipelines) are built of steel and, as a rule, they are welded.

Another issue is that high-quality work requires welding equipment and the involvement of a qualified electric welder. These measures increase the cost of the work performed, reducing the profit and competitiveness of the executive organization.

In welding electrodes, a protective coating is used, which provides alloying of the weld. This increases the strength of the metal and increases the corrosion resistance of the joint.

No. 2 - threaded water-lifting channels

When casing a well with rolled metal, 90% of drilling companies use a threaded connection, pointing to the GOST standards. It sounds convincing enough, but managers of organizations are often silent about the fact that the standards are relevant for pipes with a diameter of 146 mm and a wall thickness of at least 6 mm.

The use of threaded technology significantly reduces the life of the casing string.

In a pipe with a thickness of 4.5 mm, the thread size does not always reach 1.2-1.5 mm. Knowing the rate of corrosion (0.1 mm/year), it can be assumed that in 12-15 years the pipe will rot at the junction

The use of a threaded connection on plastic lines does not have such deplorable consequences, but, on the contrary, is considered the most reliable.

There are several options for joining polymer pipes:

1. Nipple. The thread is cut with inside plastic pipes. The two elements are connected through a nipple with an external thread. The hole diameter does not increase.
2. Coupling. Both ends of the pipe have external threads. Docking takes place with the help of an overhead coupling, which increases the diameter of the penetration.
3. Socket threaded. Segments with threads on the outer and inner surfaces are used - docking is carried out without additional elements.

In the case of a socket joint, a slight expansion of the diameter at the joints is permissible.

The socket method of docking without a thread is not used in wells - it is impossible to control the process of installing a pipe into a pipe. In addition, the connection does not provide the necessary tightness of the column and eventually sags.

Pressure or non-pressure pipeline?

The only true option is the use of pressure pipes. Only such products are able to withstand double-sided pressure. From the outside, the walls of the column are affected by the buoyancy of soils, and from the inside - by water pressure.

The arrangement of the pressure line will protect the aquifer system from premature failure. When choosing a water pipe, the indicator of its working pressure is compared with the estimated flow rate of the well

The video reviews below will help you decide on the most optimal well casing option.

Conclusions and useful video on the topic

Comparison of the quality of a threaded connection on PVC-U pipes:

The best option is a two-pipe column made of steel and plastic. The polymer is suitable for a shallow mine when arranging a "seasonal" well.

Looking for suitable option well pipes? Or have you already made your choice? Please leave comments on the article and ask your questions. The feedback form is located below.

Owners of summer cottages and capital private houses are always concerned about bringing all the necessary communications to the house: water and sewerage.

Unfortunately, it is far from always possible to connect these communications to centralized networks, and people have to independently solve the issues of supplying their homes with all these benefits, without which it is difficult to imagine modern life.

One of the main issues is the organization of water supply of the site. For most property owners, it is solved by drilling a water well within the local area.

It would seem, what is the problem? One has only to call any company that provides the relevant services, and the issue will be resolved. Yes, the problem will be solved, but the cost of solving it in different companies can vary significantly. And it depends on the materials used for the construction of the well, which will be offered to you by the specialists of a particular company.

Therefore, first you need to figure out which pipes are used when drilling wells, what advantages and disadvantages they have. And only then, having already sorted out your preferences, look for a suitable company.

If it seems to someone that a well is just a hole in the ground from which water flows and there is nothing to understand here, then he is deeply mistaken.

A well is a narrow well of great depth competently arranged in the ground, and water will not flow from it just like that.

In order to be able to receive our own water from the earth for many years, it is necessary to approach the issue of drilling a well with full responsibility otherwise, in subsequent periods, you can meet with various unpleasant phenomena.

• shedding of the walls of the well;
• well silting;
• getting into drinking water Wastewater.

Moreover, any of these phenomena leads to impossibility. In order to avoid all these problems, when constructing a water well, its walls are fixed by inserting a pipe into a narrow well, which forms the outer walls of the well and is called the "casing string".

• in one pipe, when the casing string is also a production pipe;
• into two pipes, when the production pipe, which directly supplies water, is located in a casing pipe of a larger diameter (this is done in cases where polluted waters from the overlying soil layers can penetrate into the aquifer, and also when quicksands are found during the study of the soil conditions of the site).

Most often, wells are drilled in one column, so the material of the pipes used for this must be taken seriously.

The main parameters of the well casing are:

• diameter;
• method of connecting pipe sections to each other as they sink;
• the material from which it is made.

The first two parameters can be left to the company that will drill your well, but the decision to use pipes from a certain material is purely your prerogative.

It will depend on this decision which company you choose to carry out the work, and how much it will cost you. The fact is that each specialized company has its own preferences for materials. It is unlikely that you will find one that can work with products from any materials. Therefore, it is necessary to make a decision on the material of the pipes “on the shore”.

Materials recommended for casing pipes:

• wood;
• cast iron;
• asbestos cement;
• plastic;
• steel.

As for the first two varieties, you should not pay attention to them. special attention for some reasons.

Main reasons:

• wood, being an absolutely harmless material for humans, even with special processing does not have sufficient resistance to wet soil and strength;
• cast iron is too heavy and brittle, which makes it difficult to work with it and does not guarantee the safety of the pipe even with small ground movements.

There are three main options, the features of which are worth exploring. To do this, consider the basic requirements for a casing pipe.

• it should maintain integrity and tightness as long as possible while in the ground;
• pipe material must be able to long time withstand the pressure of the soil and all its moving layers;
• the material must be safe for humans, that is, even with prolonged use, it should not affect the quality of water.

For almost a hundred years people have been using them.

And there are reasons for this:

• chemical neutrality of the material;
• resistance to corrosion;
• practically unlimited service life;
• cheapness of this type of product.

And for choice of this type pipes are mainly influenced by the last consideration - cheapness. True, some people complain about the harmfulness of asbestos fibers allegedly falling into the water. But there is no scientific evidence to back this up. In addition, these fibers are easily removed by a simple fine filter of the water coming from the well.

But this type of pipe also has more significant disadvantages that limit its use for wells.

• the fragility of the material, which requires caution when working with it;
• low strength of asbestos cement, which forces to increase the thickness of the pipe walls to achieve acceptable performance.

Therefore, only a few well drilling companies undertake to work with such pipes. If we take into account the possibility of well silting, to eliminate which it is necessary to work in a pipe with a drilling tool, then the use of a fragile asbestos-cement pipe generally loses its meaning.

The use of pipes made of polymers, including for the construction of wells, began relatively recently, so there are no reliable statistics on their use for a long time yet.

• pipes made of unplasticized polyvinyl chloride (UPVC);

All these products have the following advantages:

• they are cheap;
• they are light in weight, which facilitates their transportation and installation;
• do not emit any harmful substances into the water;
• the tightness of the connections of such pipes is quite high.

There are also disadvantages that limit their use:

• relatively low strength;
• sensitivity to mechanical influences.

• when drilling in one pipe - only for shallow wells(no more than 50 m) provided that there are no quicksands and other aquifers in the upper layers of the soil;
• when drilling in two strings as a production pipe located inside a casing string made of a more durable material.

This is a time-tested material for drilling wells.

The following types of steel pipes are used:

• stainless steel;
• galvanized pipes;
• enamelled pipes.

The last three types of pipe are used only to reduce the likelihood of rust in the water received from the well.

But the feasibility of such use is a big question:

• enameled pipes are so sensitive to mechanical stress that already during the assembly of the casing, the enamel is almost always damaged, which is the reason for the rapid development of corrosion;
• galvanized pipes are dangerous in terms of the appearance of zinc oxide in the water, which is harmful to human body;
• also do not guarantee against the appearance of rust, as well as pipes made of black steel.

And if we proceed from the fact that all these three types of pipes are much more expensive than conventional steel products, then their use is extremely limited.

Thus, ordinary steel pipes are most often used, which have advantages over products made from all other materials.

• the ability to maintain integrity for a sufficiently long time (at least 50 years), being in adverse conditions;
• sufficient strength to withstand ground movements;
• resistance to damage while drilling a well and working with a drilling tool in case of siltation.

The only disadvantage of steel products is their high cost, so steel pipes are more often used for casing deep wells, when the use of pipes made of other materials is not possible. Although, if you want to get a "long-playing" well, then the use of steel pipes is quite justified.

Whatever pipe material you choose for yourself, make sure that the pipes themselves are pressure. That is, their walls must withstand high both internal and external pressure. The cost of pressure pipes is higher, but their service life is much longer. Cheaper non-pressure pipes for well construction cannot be used.

When ordering the production of a water well from a drilling company, the owner country house expects to receive a completely ready-to-use source of pure natural water, which can last for decades.

However, it should be remembered that the qualitative composition of the produced water and the durability underground well largely depend on the material and workmanship of the pipes that make up the casing string. Therefore, when choosing a drilling contractor, it will be useful to know which well casing is best for use in each specific case.

Casing material selection

This article cannot be considered a complete instruction for installing casing pipes, because it is quite complicated. technological process, requiring the use special equipment. It is almost impossible to do it yourself at home, so for drilling a well and installing a casing string, it is best to turn to professionals for help, and further installation of pumping equipment can be done on your own.

Here we will try to understand what better pipes for the well to use as casing, and also consider basic properties pipes from various materials.

What is a casing pipe for?

The casing string pipes are lowered into the wellbore of a newly drilled well during its development, thereby protecting its walls from collapse, and the wellbore itself from falling rock from adjacent soil layers.

In addition, in an already finished well, the casing string pipes are tightly connected to each other, which prevents poorly treated groundwater (the so-called perched water) from entering its wellbore. Thus, only natural water deep cleaning from the artesian aquifer.

1. Steel is an environmentally friendly material that, in direct contact with water, does not emit any chemical elements. Common rust that forms on metal surfaces does not dissolve in water and, contrary to popular belief, does not increase iron levels. To remove it, it is enough to pass water through a regular household filter.
2. The high mechanical strength and toughness of the steel practically excludes the breakage or destruction of the casing string during its installation.

1. In case of clogging or silting of the well, as well as accidental ingress of foreign objects in it, it is allowed to perform additional drilling or other work using a drilling tool.
2. A well with such a casing can be installed even at a very deep level of the aquifer.

As for the negative qualities of this material, the main disadvantage is its rather high price. For this reason, you should carefully consider for what period of operation the installation of the well is calculated. The use of a steel casing in most cases is justified for deep artesian wells installed on the site of a capital house for permanent residence. For the arrangement of shallow wells for seasonal sand, it is better to use cheaper materials.

Advice! A seamless seamless pipe is of better quality, since the weld along the entire length is its weakest point, in which, when high loads cracks and breaks may occur.

Stainless Steel or Coated Pipe

As for the use of metal elements with additional corrosion protection, sometimes a controversial question arises: which pipes are better for a water well, galvanized or stainless steel?

In fact, answering it, you can ask a counter question: is it worth overpaying a significant amount for stainless steel, if an ordinary pipe made of black metal has a service life equal to the period of operation of the highest production well.

Separately, it should be said about galvanized black metal. The fact is that with prolonged exposure to water on zinc coating over time, zinc oxide is formed, which is considered hazardous to human health. For this reason, galvanized elements can only be used for service water.

Steel pipes with enamel coating fully comply with sanitary and hygienic standards, however, they have one significant drawback. The enamel coating has a low modulus of elasticity, so it is quite fragile. As a result, during the installation of the casing on the enamelled surface, a large number of chips and microcracks.

Water gets into them and the process of destruction begins, and through corrosion occurs even faster, because the thickness of the metal for enameled pipes is used less than for black metal.

Note! If the manager of a drilling company strongly recommends the use of any stainless materials that have a significant cost, this is more like a marketing ploy, in order to sell the client a more expensive product.

Asbestos cement pipe

Asbestos-cement pipes have been used for well casing for many years and are an inexpensive alternative to steel products, but not all drilling companies, due to the nature of this material, are able to mount them correctly.

1. Asbestos cement is environmentally friendly chemically neutral natural material and during operation does not emit any harmful substances into the water.
2. The claim that asbestos is carcinogenic is scientifically unfounded. In addition, the number of fibers that can get into the water is negligible, and given the peculiarities of their structure, they can be filtered out by any household filter.
3. Asbestos cement products are very fragile, so special care must be taken when installing them. For the same reason, it is unacceptable to perform drilling operations in an already finished well.
4. Due to the large wall thickness, the installation of asbestos-cement pipes requires a borehole of a larger diameter than steel pipes.
5. They cannot be used as a filtration column in sand wells, therefore they are used only in artesian sources.
6. Due to the physical features of this material, their installation is allowed only in wells whose depth does not exceed 100 m.

plastic pipe

Relatively new materials for casing can be considered pipes made of various polymers: uPVC (unplasticized polyvinyl chloride); HDPE (low pressure polyethylene) and PP (polypropylene). Among the advantages of these materials, the following properties can be noted:

1. Absolutely not subject to corrosion even with prolonged contact with water.
2. They do not break down in the soil and do not contribute to the development of pathogens.
3. They do not emit any harmful substances into the water.
4. The main advantage of plastic products is their low cost and light weight.

Given the low strength of polymer products, the maximum depth of the well with their use should not exceed 60 meters.

Advice! As for the question,which pipe is better for a well, of plastic products, the most optimal in terms of price and reliability is the nPVC polymer.

Conclusion

After reading the material in this article, you can more confidently seek help in installing a well from the specialists of a drilling company. A competent manager who sees that the client is at least a little versed in this issue will not frankly offer him a product of inadequate quality.

More detailed information on the issue of interest can be obtained by watching the video in this article or reading other materials in this section.