Arrangement of a well on a country site will provide its owners with water. But without proper preparation, it cannot be used for cooking and drinking purposes. For pre-cleaning, you can make a filter for the well with your own hands. Practical home-made cost will be much less than the sales proposal. And this is a lot, agree?
You can get acquainted with the noteworthy information based on the requirements of the standards by reading the presented article. The information contained in it will be useful both for independent masters and customers of drillers services. Knowledge of the design of the filtering device and the specifics of caring for it will also serve during the operation.
The article lists the types of downhole filters that will help determine the best option. The construction technology has been scrupulously analyzed; technical details of the manufacturing and installation process are listed. For a better perception of impressive information material, photos, diagrams and videos are shown.
The content of the article:
- Device and purpose of the downhole filter
Materials for filtration equipment
- Nuances of using stainless steel
- Features of the use of plastic
- Subtleties of using ferrous metals
Construction varieties of filters
- Option # 1 - Perforated Filter
- Option # 2 - slot models
- Option # 3 - strainers
- Option # 4 - Wire Filter
- Option # 5 - gravel backfill
- Conclusions and useful video on the topic
Device and purpose of the downhole filter
All filters for wells have a similar structure. They work in a single and multi-level water purification systems. They are responsible for mechanical cleaning, preventing particles of soil, grains of sand and other relatively large debris from getting inside the casing.
Filters consist of three main elements, located from top to bottom:
- Overfilter area. The part that serves as a kind of fitting when attaching the device to the casing.
- Filter element. A baffle with holes that prevents dirt particles from penetrating inside the filter.
- Sump. Capacity for collecting large particles, managed to penetrate into the casing.
To improve cleaning, a multi-level system can be used, suggesting the presence of additional flow filtersthat are already installed in front of the crane.
A well filter prevents large mineral particles from entering the inside of the column. Due to this, clean water is supplied to the surface, and downhole equipment is protected from overloads
The devices used for primary cleaning are divided into two groups:
- Pre-filtered. Between the outer wall of the well and the surface of the casing there is a layer of marble chips or gravel that “collects” dirt and prevents the filter from silting up quickly.
- Without pre-filtering.
The filter element of the variant without prior filtration is in contact directly with the aquifer.
The filtering part of the well filter “covers” only the aquifer, plus half a meter higher and lower. Throughout the remaining casing height, the pipes are not permeable, the links of the links are tight
The main purpose of the downhole filter is to purify water from unnecessary impurities. However, the device removes only large pollution, after-treatment is obligatory after it. This is the only way to reduce mineralization and hardness, reduce the concentration of fluorine, manganese and iron.
The choice of the type of additional filtration system depends on the chemical composition of the water coming from the well. In addition to the main task, the well filter performs minor functions.
With the arguments in favor of the use of well filters will introduce a selection of photos:
A photo of
Filters are installed in the wellbore on the sand, because in the process of pumping a lot of sand suspension gets into the water
When pumping water from a sand well that is not equipped with a filter, the pump must be cleaned ten times more often, it serves less because of the increased load on the engine
Extremely low quality water flows from the well to the sand, in which no filter is installed.
Non-filtered water clogs pipes, before the time promised by the manufacturer, disables heating equipment
Pumping out muddy water with grains of sand.
Breakage of pumps in sandy slopes
Dirty water from a well without filter
Untreated water wears equipment
It provides long life of the well and equipment immersed in it, because it protects them from impurities that can quickly fill the barrel. In this case, the well will be silted up, become inoperable and need cleaning.
It is important to understand that pump equipment It is not intended for long-term work with increased load, which is inevitable when water rises with solid particles dissolved in it.
In such conditions, the pump is experiencing overload and very quickly fails. In addition, the filter supports the walls of the well, protecting them from collapse and rockfall.
Materials for filtration equipment
The materials used are stainless steel, plastic and ferrous metals. Let us consider in more detail the features and characteristics of each of them.
Nuances of using stainless steel
The best material for the manufacture of downhole filters is stainless steel. It is able to withstand high crushing and bending effects, and doping makes it impervious to oxidation.
Stainless steel pipes are characterized by a long service life, but their cost is quite high.
All the performance characteristics of stainless steel are also characteristic of the filter mesh and wire used for winding onto the part.
For the manufacture of the downhole filter uses a special mesh of metal or synthetic fibers
Features of the use of plastic
Plastic is another material that is widely used to make filters. Plastic is absolutely inert, therefore not subject to oxidation. It is very easy to handle and has a long service life.
The cost of plastic parts is low, which attracts well owners.
Plastic pipe downhole filters are very easy to process and are inexpensive. However, they can only be used at shallow depths, due to the small margin of safety
The main disadvantage of plastic is low strength. As a result, it is not able to withstand severe compressive loads, which are characteristic of great depths.
Subtleties of using ferrous metals
Ferrous metals as filters can only be used for wells that provide water for technical purposes. This is due to the fact that they are oxidized by water, as a result of which iron oxide appears in it. Doctors have not proved that it is harmful to the body.
However, if the concentration of this substance is greater than 0.3 mg / l, water will leave unpleasant yellow spots on plumbing, dishes and underwear. Galvanized ferrous metals are also subject to oxidation.
Visually, water with a small amount of impurities looks practically transparent. But the plaque formed on the plumbing, makes you think about the health risks of using such water as drinking water.
As a result, not only iron oxide, but also zinc oxide appears in the water. The latter irritates the mucous membranes and leads to indigestion.
Thus, experts strongly do not recommend the use of ferrous metals for the manufacture of filters for the well, including galvanized metals.
This applies not only to the basics, but also to the filter screen, the lower sections of the casing, as well as the wire that is used in fastening and fabricating the structure. Otherwise, water obtained from a well with such a filter can only be used for technical purposes.
Thus, for deep wells it is best to use stainless steel parts, and for shallow depths or in the case of additional casing, it is optimal to mount plastic accessories.
Construction varieties of filters
There are several types of downhole filters, each of which is designed to operate in certain conditions. The choice of design is determined by the geological characteristics of the aquifer.
Artesian wells are drilled in stable and hard calcareous rocks, which makes it possible to operate them without a filter. The barrel is simply left open.
Good water pressure, which is typical for such wells, allows you to set submersible pump at an impressive distance from the bottom, so the flowing water does not need coarse treatment.
There are almost no fine-grained impurities in the limestone, and the ingress of large particles of rock into it is practically impossible. If the well is made in unstable gravel, saline or pebble rocks from large and fine particles, a filter is necessary.
Accordingly, the pump should be installed close enough to the water intake, which makes it necessary to have a filter. Most often it is a perforated or slotted filter, which is designed only for coarse cleaning. If there is no sand in the aquifer, the device will work efficiently and will last a very long time.
The most "capricious" are wells made in sandy soils. They deliver the maximum trouble to their owners and drillers. Practice shows that they are most common, since sandy water carriers most often are located closest to the surface.
Wells on the sand can not be operated without mesh type filter. Moreover, the life of the well depends on the quality of its manufacture and the material from which it is made. Let us consider in detail each of the types of downhole filters.
There are various types of downhole filters. The figure shows a few of them used in the construction of the well-needle
Option # 1 - Perforated Filter
Perforated structures are also called perforated because they are a pipe with holes arranged in a specific order. Such filters are able to withstand fairly high loads, since the annular rigidity of the pipe is not reduced.
That is why they are allowed to be used at great depths, even with a high likelihood of soil movements. Experts recommend installing perforated filters on wells with little pressure.
Over time, the performance of such a filter inevitably decreases, since the holes in the pipe are silted.
The diameter of the holes of the perforated filter should be less than the average particle size of the rock in which the well is being drilled.
The device can be made independently. To do this, you need: a drill, a grinding material, a plug of moisture-resistant wood and a pipe of the desired diameter. It is better if it is from an oil or exploration assortment.
If plastic is chosen, make sure it is safe for humans. The size of the holes depends on the type of rock, so the diameter of the drill is selected on the basis of its grain size indicators. The holes on the pipe body can be arranged in a linear or staggered manner.
Their number is chosen in the ratio of 1: 4, that is, a quarter of the entire pipe must have perforations. Holes are placed with a minimum step of 2-3 cm.
The operations for the production of the perforated filter are performed in the following sequence:
- We lay the pipe on a horizontal surface and proceed to the markup. From one end we mark the length of the settler, approximately 50 cm. Directly behind it is the filter part, on which we mark the holes. Do not forget that it occupies of the entire pipe.
- We drill the first hole. We have a cutting tool relative to the pipe surface at an angle of from 30 to 60 °. We drill in the bottom-up direction relative to the proposed vertical placement. The result is an oval hole of a larger area.
- Similarly, we perform all the necessary holes in accordance with the markup.
- Using a grinding material, gently clean all the holes.
- Raise the pipe, set it vertically. Carefully release the internal cavity of the filter from the chips that could remain in it and close the holes.
- We take a wooden cap and close the lower part of the pipe with it.
Homemade perforated filter for the well is ready.
Option # 2 - slot models
Slot-holes are very similar to perforated filters, but instead of holes they are equipped with slots.
Which can be located as follows:
- Staggered horizontally. The slot segment is executed, the block following it is cut with a 45 ° rotation. This makes it possible to provide the necessary structural strength without performing special stiffeners.
- Upright. The distance between the slits must be at least 10 mm. Such systems are similar to wire filters for a well on sand.
- Horizontally with multiple slots segments. The distance between the perforated sections, which is called the stiffness belt, should not be less than 20 mm, otherwise the pipe will lose the necessary strength. The slot pitch is at least 10 mm.
Slotted filters are used in unstable soil, where the percentage of pebbles, crushed stone or gravel is high. They can also be used in case of a high risk of rock collapse. A distinctive feature of the slotted filter is a higher well debit.
This is due to the fact that the area of the slot located on the core frame is about a hundred times larger than the hole area of the perforated filter. The main disadvantage of the design is a high probability of blocking the gaps with fine-grained sand.
Slot-type downhole filters are distinguished by high performance. Their use has virtually no effect on well debit.
For independently manufacturing a slot-type filter you will need: a pipe, a metal or plastic, a wooden plug and a tool for milling, or cutting torch (torch). It all depends on how the slits are made.
Operations are performed in the following sequence:
- We lay the pipe on a horizontal surface and mark it. We deviate from one edge of about 50 cm, it will be a sump. Then we outline the location of the slots, not forgetting the stiffness belt, if the slots are located horizontally.
- On the basis of the marking in any suitable way we make slots.
- Raise the pipe and free it from the inside of chips and dirt that could get there in the process.
- Install the stub.
The filter is ready for operation.
With the order of execution of works on the construction of the well filter, a photo gallery will present:
A photo of
The first step is perforation of the pipe. The diameter of the holes 10 - 12 mm, the distance between them is about 10 - 15 cm
Aluminum wire is wound on a pre-perforated pipe. Between adjacent turns 5 cm
We fasten a synthetic mesh to the turns of aluminum wire, which used to clean milk on farms
Grid tightly wrapped pipe of the future filter, fastened to the wire with a fishing line
The net is once again firmly fastened and connected to the seam with a wire.
The edges of the wire wound on the screws screwed into the tube on both sides
In order to install a filter in the well and to build up the barrel of the inner pipe to the required length, a collar is necessary to stop the column in the barrel, or, for example, bags of soil
Much easier, but more expensive to use products for the construction of wells, manufactured in production. They are also produced with a geotextile winding, which in the example was replaced by a grid
Stage 1: Making a filter for a water well
Stage 2: Winding the wire onto a perforated tube
Stage 3: Fixing the mesh to the perforated pipe
Stage 4: Fine Filter Device
Step 5: Duplicating the fastener synthetic mesh
Step 6: Fixing the fixing wire to the tube
Stage 7: Installing a homemade filter in the well
Well Well Filters
Option # 3 - strainers
Such systems are designed for installation on clay-sandy water carriers.
The strainer is a base in the form of a perforated or slit construction, on which a fine-mesh mesh is attached to perform finer filtration. The size and shape of its cells may vary.
Mesh filters for wells are designed for use in sandy rocks. Small cells delay grains of sand
Such a system is considered to be quite durable and durable. Its main disadvantage is the reduced performance, because the small holes in the grid create a fairly strong resistance to flow.
In hard water, such filters quickly become clogged with particles of iron compounds.
The grid that covers the structure can be:
- standard with square-shaped cells;
- keeperconsisting of several layers;
- galloon with cells of complex shape.
The type of soil determines the choice of grid. For gravel and coarse sand pick up a keeper or standard mesh, for fine and medium-grained rocks - galloon. Cell sizes can vary from 0.12 to 3 square meters. mm To correctly determine the size using the method of testing.
Gather the soil from the well, then sift it through different mesh patterns. The one that will delay at least half of the soil particles can be considered suitable for work. To determine the size of the cells and, accordingly, of soil particles, a handful of soil is poured onto the millimeter paper from the well.
Filter screens can be made of different materials:
- Metal - brass or stainless steel. Such products are durable, their cells, if necessary, can be easily cleaned. The main disadvantage of brass products is a high probability that when installing the mesh cells can be deformed, making it difficult for water to enter the inside of the filter column.
- Fiberglass or carbon fiber. They are not deformed during installation, differ in long service life. The main difficulty in operation is to clean the grid.
Regular washing will not be enough, you will have to use more complex methods: chemical reagents, electrical discharges or hydrodynamic shock.
Stainless steel wire braid weave. Suitable for working on medium to fine grained soils.
For self-manufacturing mesh filter will need: a pipe made of plastic or metal, wooden plug, mesh, wire with a cross section of at least 3 mm, a soldering iron and a drill or milling tool, depending on the chosen method perforation.
- We place the pipe on a flat horizontal surface and mark it under the perforation.
- In accordance with the marking we make holes or slots.
- We impose a wire over the perforation. Wind it under an inclination of 30-45 °, while the distance between adjacent turns should be 2 ± 0.5 cm. Every 5-10 cm we perform a point soldering, fixing the wire to the base.
- We check the quality of the winding made, if necessary, repeat the soldering.
- We impose a wire on the wire and wrap the body of the pipe with it and fasten it.
In the case of metal mesh, we use soldering, soldering the web to the wire, plastic parts are fixed with metal wire.
A photo of
The diameter of the filter for the well is chosen so that its maximum dimensions together with the protruding elements are smaller than the diameter of the casing. It should be possible to remove the filter for cleaning.
The length of the well filter is calculated based on the geological conditions of a particular site. Its top should be above the groundwater mirror by 0.5 - 1 m and the same distance below the base of the aquifer
Before installing the filter in the well, the production is flushed until the extracted water is completely clarified.
For arranging shallow sand wells a plastic filter can be used that is installed in a steel casing.
The diameter of the filter for the arrangement of wells
Well filter lengths
Preparing to install the filter in the barrel
Plastic filter in steel casing
Option # 4 - Wire Filter
Such a device can be considered a kind of mesh filter with the difference that instead of a mesh, a special wedge-shaped wire is wound on the base of a spiral. The size of the particles retained by such a filter is determined by the shape of the wire and the winding pitch.
Filters of this type compare favorably with mesh counterparts with high strength and long service life, due to the greater thickness of the wire compared to the grid. It is clear that we are talking about high-quality frame-core products, which are almost impossible to perform independently.
The wire borehole filter is the most durable and durable design. Diagram of the device is shown in the figure.
At the same time mesh filters transfer local damage more easily. In the case of the destruction of one or several cells of the grid, in this area, it will pass into the column larger particles of contamination. However, the rest of the filter will fully retain its properties.
For wire filters, it is otherwise. If the winding is damaged, the product loses filtering properties in the segment between two adjacent points of the winding fastening to the frame in the gust area. In addition, the cost of strainers is much lower. This is due to the fact that they are easier to manufacture.
Quality wire filters are almost impossible to make yourself. If you still really want to try, you will need a metal pipe of the desired diameter, plug, milling tool or gas cutter, metal rods, a soldering iron and a wedge-shaped wire.
First, the base is made in the form of a slotted filter, the width of the slots of which must correspond to the average diameter of the rock particles. We place 10 or 12 metal rods with a diameter of at least 5 mm on the prepared frame.
They will not allow the wire to lie directly on the frame and close its openings. The base is ready, you can start winding the wire. The peculiarity of the manufacture of the wire filter is that it is wound on the frame under tension. It will be easier to wind up using a lathe.
If this is not possible, the operation is performed manually, which is very time consuming and requires special care and patience. In the process of winding, the coils of wire laid with the required pitch are necessarily fixed to the base by soldering.
Gravel filter frame type. This design requires that the diameter of the well is larger than necessary only for the pipe.
Option # 5 - gravel backfill
Small in size smooth fragments of hard stone or gravel can be considered a natural filter with a sufficiently high cleaning effect.
He is able to retain even very small elements of pollution and has the ability to self-cleaning. On this basis, small gravel can be used as an additional filter.
To this end, it is placed in the zone of water intake wells. The effectiveness of such a filter depends on the characteristics of the gravel and the height of its layer. The more particles of pollution settle on the gravel, the less they fall into the main filter, which significantly prolongs the work of the well.
There are two types of gravel filters:
- Filling in. It is a layer of material, poured directly into the well through the annulus openings. It can be used only for structures whose diameter does not exceed 10 cm at the site of the filtering part.
- Assembled on the surface. Stuffing gravel mix is made in the cavity between the two layers of filter material from wire or mesh. Such a circuit after packing is lowered into the well. The width of its walls does not exceed 3 cm.
Only the first type of filter can be made independently. First of all, you need to prepare gravel. Work should be taken with great responsibility, since the quality of the filter depends on the quality of the material.
First choose the diameter of the gravel. It should be on average 5-10 times smaller than the diameter of the well pipe.
All items are selected in size, calibrate. It is desirable that they be the same size. If the material is very dirty, you may have to wash it. When setting up a gravel filter, the preparatory work begins at the stage well drilling.
You may also be interested in information about how well drilling and how rock it after drilling.
The hole for it is made with regard to future sprinkling, that is, slightly larger than the required diameter. After the well is ready, prepared gravel is poured from the wellhead. Spraying thickness - not less than 50 mm.
Carefully selected gravel is poured at the wellhead. The minimum width of dusting is 5 cm
Practice shows that even a novice home wizard will be able to make a filter for the well independently. Such designs are easy to manufacture and install. It is only important to correctly determine the type of filtering device and correctly select the material from which it will be made.
Conclusions and useful video on the topic
Step-by-step instructions for the fabrication of the mesh filter:
And this video will introduce the sequence of work on the production of a downhole filter from a plastic pipe:
If everything is done according to the rules, the filter will last for a very long time, clearing the water that flows into the house from contamination and protecting the well equipment from overloads and premature failure.
Do you have a self-made filter in the well, made according to one of the instructions discussed in the article? Tell us if it was difficult for you to collect it and what nuances you encountered.
Or in the process of building a filtering device do you have any questions? Feel free to ask for advice, leaving your question in the comments block - we will try to help you.