Do you want to know what is the most effective corrosion protection for steel pipes? During operation, metal pipes are constantly exposed to various unfavorable factors. To solve this problem, comprehensive protection of pipelines against corrosion has been specially developed in accordance with SNiP 2.03.11-85 “Protection building structures from corrosion."

External polymer coating — reliable protection against corrosion of steel pipes

Corrosion control methods

This article invites the reader detailed instructions, which describes in detail the basic principles of anti-corrosion protection for metal products. I will tell you how to protect any metal surface from corrosion.

Classification of harmful factors

According to the mechanism of occurrence and the degree of destructive impact, all harmful factors can be divided into several types.

1. Atmospheric corrosion occurs when iron interacts with water vapor contained in the surrounding air, as well as as a result of direct contact with water during precipitation. During the chemical reaction, iron oxide is formed, or, more simply, ordinary rust, which significantly reduces the strength of metal products, and over time can lead to their complete destruction.

Electrochemical corrosion underground destroys even thick-walled pipes

1. Chemical corrosion occurs as a result of the interaction of iron with various active chemical compounds (acids, alkalis, etc.). At the same time, leaking chemical reactions lead to the formation of other compounds (salts, oxides, etc.), which, like rust, gradually destroy the metal.
2. Electrochemical corrosion occurs in cases where an iron product is in an electrolyte environment for a long time ( water solution salts of varying concentrations). In this case, anodic and cathodic areas are formed on the surface of the metal, between which an electric current flows. As a result of electrochemical emission, iron particles are transferred from one area to another, which leads to the destruction of the metal product.
3. Impact negative temperatures in cases where pipes are used to transport water, it leads to freezing. Upon transition to a solid state of aggregation, a crystal lattice is formed in water, as a result of which its volume increases by 9%. Being in a confined space, water begins to put pressure on the walls of the pipe, which ultimately leads to their rupture.

Note!

A significant difference in average annual and average daily temperatures leads to significant fluctuations in the total length of the pipeline, which are caused by the linear thermal expansion of the material. To prevent pipe rupture and damage load-bearing structures, after a certain distance on the line it is necessary to install thermal compensators.

Soil analysis

In order to choose the most effective method protection, it is necessary to have accurate information about the nature of the environment and specific operating conditions steel pipeline. In case of laying internal or overhead line this information can be obtained on the basis of subjective observations, as well as based on the average annual climate regime for a given region.

In the case of laying an underground pipeline, the corrosion resistance and durability of the metal largely depend on the physical parameters and chemical composition soil, so before digging a trench with your own hands, you need to submit soil samples for analysis to a specialized laboratory.

The most important indicators that need to be clarified during the analysis process are the following soil qualities:

1. Chemical composition and salt concentration various metals V groundwater. The density of the electrolyte and the electrical permeability of the soil largely depend on this indicator.
2. Qualitative indicator of acidity soil, which can cause both chemical oxidation and electrochemical corrosion metal
3. Electrical resistance of the earth. The lower the electrical resistance value, the more susceptible the metal is to the destructive effects caused by electrochemical emission.

Note!

To obtain objective analysis results, soil samples must be removed from the soil layers in which the pipeline will pass.

Low temperature protection

In the case of underground or overhead installation of water and sewer networks, the most important condition for their uninterrupted operation is to protect the pipes from freezing and maintain the water temperature at a level not lower than 0°C during the cold season. To reduce the negative impact temperature factor environment, the following technical solutions are used:

1. Laying an underground pipeline at depth, exceeding maximum depth soil freezing for a given region.
2. Thermal insulation air and underground lines with help various materials with low thermal conductivity (mineral wool, foam segments, foam propylene sleeves).

Foil sleeves made of mineral wool for pipe insulation

1. backfilling pipeline trenches bulk material with low thermal conductivity (expanded clay, coal slag).
2. Drainage adjacent layers of soil in order to reduce its thermal conductivity.
3. Pad underground communications in rigid closed boxes made of reinforced concrete, which ensure the availability air gap between the pipe and the ground.

The most progressive method of how to protect pipes from freezing is to use a special casing consisting of a shell made of thermal insulation material, inside of which an electric heating element is placed.

Note!

The depth of soil freezing for each specific region, as well as the methodology for its calculation, is regulated regulatory documents SNiP 2.02.01-83* “Foundations of buildings and structures” and SNiP 23-01-99* “Building climatology”.

External waterproofing coating

The most common way to combat metal corrosion is to apply a thin layer of durable, waterproof protective material to its surface.

I will give simple examples:

1. The most common option protective coating is ordinary waterproof paint or enamel. For example, protection gas pipe passing through the air is always done using weather-resistant yellow enamel;
2. Underground water and gas communications are assembled from steel pipes, which are pre-coated on the outside with a thick layer bitumen mastic, and then wrapped in thick technical paper:
3. Also high efficiency have coatings made of composite or polymer materials;
4. Cast iron elements of sewer lines are covered inside and out with a thick layer of cement-sand mortar, which, after hardening, forms a homogeneous monolithic surface. This way you can protect the support.

To choose the right suitable material for external coating, you need to know that anti-corrosion protection of metal must simultaneously have several qualities.

1. Paintwork after drying it should have a continuous homogeneous surface with a high mechanical strength and absolute resistance to water;
2. Protective film waterproofing material, with the specified properties, must be elastic and not collapse under the influence of high or low temperatures;
3. Raw material to apply the coating it must have good fluidity, high covering ability, as well as good adhesion to the metal surface;
4. Anti-corrosion treatment applied to a dry, clean metal surface;
5. Electrical conductivity. Another indicator of a high-quality insulating material is that it must be an absolute dielectric. Thanks to this property, reliable protection of pipelines from stray currents, which enhance the adverse effects of electrochemical corrosion.

Note!

Most effective solutions For waterproofing metal, it is customary to consider compositions based on bitumen resins, two-component polymer compositions, as well as roll polymer materials on a self-adhesive basis.

Active and passive electrochemical protection

Underground engineering Communication are more susceptible to the occurrence of corrosion centers than air and internal pipelines, because they are constantly in an electrolyte environment, which is a solution of salts contained in groundwater.

In order to minimize the destructive effects caused by the reaction of iron with a water-salt electrolyte solution, active and passive methods of electrochemical protection are used.

1. Active cathode method consists in the directional movement of electrons in a constant circuit electric current:

• To do this, to the negative pole of the source direct current a pipeline is connected, and an anode grounding rod is connected to the positive one, which is buried in the ground nearby;
• After applying voltage, electrical circuit closes through the soil electrolyte, as a result of which free electrons begin to move from the ground rod to the pipeline;
• Thus, the grounding electrode is gradually destroyed, and the released electrons react with the electrolyte instead of the pipeline.

1. Passive tread protection pipelines is as follows:

• An electrode made of a more electronegative metal, such as zinc or magnesium, is placed near the iron in the ground;
• The steel pipe and the electrode are connected electrically through a controlled load;
• In the electrolyte environment they form a galvanic couple, which during the reaction causes the movement of electrons from the zinc protector to the protected pipeline.

3.Electrical drainage protection is also a passive method, which is performed by connecting the pipeline to the ground loop:

• The connection is made in accordance with the requirements of the PUE;
• This method helps to get rid of the occurrence of stray currents and is used if the pipeline is located near the contact electrical network of ground or rail transport.

Note!

A clear example passive protective protection is the well-known zinc coating of iron products, or, more simply, galvanization.

Conclusion

Each of the above methods has its own advantages and disadvantages, so they must be used depending on specific conditions. In conclusion, I can only say that regardless of the chosen method, the cost of repairing and replacing the pipeline will cost much more than the cost of the most complex and time-consuming protection.

Almost any internal infrastructure and life support system residential buildings, municipal and commercial buildings or industrial facilities, By by and large is a developed network of pipelines connecting certain system objects to each other in a certain order.

In most cases, for example, when installing a gas pipeline, hot and cold water supply, sewage or cable and ventilation, underground, air or internal installation is used metal pipes various diameters and size.

Depending on the operating mode and environmental conditions, metal pipes during operation may be subject to prolonged exposure to various adverse factors. To solve this problem, comprehensive protection of pipelines from corrosion has been specially developed in accordance with SNiP 2.03.11-85 “Protection of building structures from corrosion.”

Corrosion control methods

To help the reader understand how to ensure maximum pipeline longevity, this article will discuss some options for active and passive protection of metal products that are part of pipeline utilities.

There will also be detailed instructions that describe in detail the basic principles of anti-corrosion protection for metal products intended for use in aggressive conditions.

Classification of harmful factors

As mentioned above, the nature and degree of influence external factors largely depends on specific operating conditions, such as the location of the pipe, the chemical composition of the soil, the average annual temperature and relative humidity of the environment, the presence of nearby DC sources, etc.

According to the mechanism of occurrence and the degree of destructive impact, all harmful factors can be divided into several types.

1. Atmospheric corrosion occurs when iron interacts with water vapor contained in the surrounding air, as well as as a result of direct contact with water during precipitation. During the chemical reaction, iron oxide is formed, or, more simply, ordinary rust, which significantly reduces the strength of metal products, and over time can lead to their complete destruction.

1. Chemical corrosion occurs as a result of the interaction of iron with various active chemical compounds (acids, alkalis, etc.). In this case, the ongoing chemical reactions lead to the formation of other compounds (salts, oxides, etc.), which, like rust, gradually destroy the metal.
2. Electrochemical corrosion occurs in cases where an iron product is in an electrolyte environment (an aqueous solution of salts of varying concentrations) for a long time. In this case, anodic and cathodic areas are formed on the surface of the metal, between which an electric current flows. As a result of electrochemical emission, iron particles are transferred from one area to another, which leads to the destruction of the metal product.
3. Exposure to freezing temperatures in cases where pipes are used to transport water, it leads to freezing. Upon transition to a solid state of aggregation, a crystal lattice is formed in water, as a result of which its volume increases by 9%. Being in a confined space, water begins to put pressure on the walls of the pipe, which ultimately leads to their rupture.

Note! A significant difference in average annual and average daily temperatures leads to significant fluctuations in the total length of the pipeline, which are caused by the linear thermal expansion of the material. To prevent rupture of pipes and damage to supporting structures, it is necessary to install thermal compensators at a certain distance along the line.

Soil analysis

In order to choose the most effective method of protection, it is necessary to have accurate information about the nature of the environment and the specific operating conditions of the steel pipeline. In the case of laying an internal or overhead line, this information can be obtained on the basis of subjective observations, as well as based on the average annual climate regime for a given region.

In the case of laying an underground pipeline, the corrosion resistance and durability of the metal largely depend on the physical parameters and chemical composition of the soil, so before digging a trench with your own hands, it is necessary to submit soil samples for analysis to a specialized laboratory.

The most important indicators that need to be clarified during the analysis process are the following soil qualities:

1. Chemical composition and concentration of salts of various metals in groundwater. The density of the electrolyte and the electrical permeability of the soil largely depend on this indicator.
2. Qualitative and quantitative indicators of soil acidity, which can cause both chemical oxidation and electrochemical corrosion of metal.
3. Electrical resistance of the soil. The lower the electrical resistance value, the more susceptible the metal is to the destructive effects caused by electrochemical emission.

Advice! To obtain objective analysis results, soil samples must be removed from the soil layers in which the pipeline will pass.

Low temperature protection

In the case of underground or air, the most important condition for their uninterrupted operation is to protect the pipes from freezing and maintain the water temperature at a level not lower than 0°C during the cold season.

To reduce the negative impact of the environmental temperature factor, the following technical solutions are used:

1. Laying an underground pipeline at a depth exceeding the maximum soil freezing depth for a given region.
2. Thermal insulation of overhead and underground lines using various materials with low thermal conductivity (mineral wool, foam segments, polypropylene foam sleeves).

1. Backfilling of the pipeline trench with bulk material with low thermal conductivity (expanded clay, coal slag).
2. Drainage of adjacent soil layers in order to reduce its thermal conductivity.
3. Laying underground communications in rigid closed boxes made of reinforced concrete, which provide an air gap between the pipe and the ground.

The most progressive method of protecting pipes from freezing is to use a special casing consisting of a shell made of thermal insulation material, inside which an electric heating element is placed.

Note! The depth of soil freezing for each specific region, as well as the methodology for its calculation, is regulated by regulatory documents SNiP 2.02.01-83* “Foundations of buildings and structures” and SNiP 23-01-99* “Building climatology”.

External waterproofing coating

The most common way to combat metal corrosion is to apply a thin layer of durable, waterproof protective material to its surface. The simplest example of an external protective coating is ordinary waterproof paint or enamel, for example the protection of a gas pipe passing through the air is always done with weatherproof yellow enamel.

Underground water and gas pipelines are usually assembled from pipes that are pre-coated on the outside with a thick layer of bitumen mastic and then wrapped in thick technical paper. Coatings made of composite or polymer materials are also highly effective.

The metal elements of underground sewer utilities are covered from the inside and outside with a thick layer of cement-sand mortar, which, after hardening, forms a homogeneous monolithic surface.

To independently select the appropriate material for the outer covering, you need to know that in order to provide maximum protection, it must simultaneously have several qualities.

1. After drying, the paint coating must have a continuous, uniform surface with high mechanical strength and absolute resistance to water.
2. The protective film of the waterproofing material, with the specified properties, must be elastic and not collapse under the influence of high or low temperatures.
3. The starting material for coating must have good fluidity, high covering ability, as well as good adhesion to the metal surface.
4. Another indicator of a high-quality insulating material is that it must be an absolute dielectric. Thanks to this property, reliable protection of pipelines is provided from stray currents, which enhance the adverse effects of electrochemical corrosion.

Advice! The most effective solutions for isolating metal from the environment are considered to be compositions based on bitumen resins, two-component polymer compositions, as well as roll polymer materials on a self-adhesive basis.

Active and passive electrochemical protection

Underground utility lines are more susceptible to corrosion than air and internal pipelines, because they are constantly in an electrolyte environment, which is a solution of salts contained in groundwater.

In order to minimize the destructive effects caused by the reaction of iron with a water-salt electrolyte solution, active and passive methods of electrochemical protection are used.

1. Active cathode method consists in the directed movement of electrons in a direct electric current circuit. To do this, a pipeline is connected to the negative pole of the DC source, and an anode grounding rod is connected to the positive pole, which is buried in the ground nearby. Once voltage is applied, the electrical circuit is completed through the soil electrolyte, causing free electrons to move from the ground rod to the pipeline. Thus, the grounding electrode is gradually destroyed, and the released electrons react with the electrolyte instead of the pipeline.

1. Passive tread protection of pipelines consists of placing an electrode of a more electronegative metal, such as zinc or magnesium, next to iron in the ground, and connecting them electrically through a controlled load. In the electrolyte environment they form a galvanic couple, which during the reaction, as in the previous case, causes the movement of electrons from the zinc protector to the protected pipeline.
2. Electrical drainage protection is also a passive method, which is performed by connecting the pipeline to a grounding loop made in accordance with the PUE. This method helps to get rid of the occurrence of stray currents and is used if the pipeline is located near the contact electrical network of ground or rail transport.

Note! A clear example of passive protective protection is the well-known zinc coating of iron products, or, more simply, galvanization.

Conclusion

Each of the above methods has its own advantages and disadvantages, so they should be used depending on the specific conditions prevailing. In conclusion, it should only be said that regardless of the chosen method, the cost of repairing and replacing the pipeline will be much more expensive than the cost of the most complex and time-consuming protection.

For getting additional information You can watch the video in this article or read similar materials on our website.

Metal pipes have many advantages, but during their operation everyone can face one problem - corrosion. Corrosion of pipes leads to a reduction in their service life and waste of a huge mass of metal, especially if we're talking about about steel pipes. In connection with it, accidents and water leaks occur on water supply lines, and because of it, the roughness increases inner surface pipes, which is accompanied by the appearance of additional resistance, a drop in water pressure and, ultimately, an increase in the cost of supplying it.
In other words, metal corrosion creates the need for additional construction and operating costs in water supply systems. That is why special attention is paid to the fight against corrosion in plumbing practice.

Causes of corrosion from outside and inside pipes

Metal corrosion affects both internal and outer surface pipe walls. Corrosion from outside pipes occurs due to metal contact with soil, which is why it is sometimes called soil corrosion. Solutions of salts contained in the soil are liquid electrolytes, and therefore they destroy the structure of the metal during prolonged interaction with it. As a special characteristic of soil, its corrosive activity is distinguished, which is inversely proportional to the electrical resistance of the soil, that is, the higher electrical resistance, the less corrosive activity of the soil, and vice versa - the lower the electrical resistance of the soil, the higher its corrosive activity. Thanks to the fact that this dependence is known, specialists can determine the corrosive activity of soils by measuring only the level of their electrical resistance.
Corrosion inside pipes occurs from the corrosive properties of the water itself. Water with a low pH value and a high content of oxygen, sulfates, chlorides and dissolved carbon dioxide quickly leads to corrosion of the inner surface of the walls of metal pipes.

Methods for protecting metal pipes from corrosion

External insulation

First and in the most important way There is external insulation. In addition to anti-corrosion functions, it reduces heat loss and provides mechanical protection. Can be used to create insulation different materials, let's briefly consider the possible options.
1. Bitumen insulation. It consists of a layer of polyethylene, which is protected by a bitumen coating. Sometimes there may be fiberglass wrapped around the pipes. Can be used for pipelines located in clay, sandy and rocky soils.
2. Polyethylene anti-corrosion insulation. It consists of a multi-layer coating, specially designed to protect pipelines from corrosion.
3. Polyurethane foam insulation. There are two types. The first is the use of polyurethane foam shells, used for above-ground and underground pipelines for channel and non-channel pipe installation. The second is the creation of a polyurethane foam shell by injecting liquid polyurethane foam between the pipe and pre-created polyethylene insulation, after which the polyurethane foam hardens and turns into a complete shell.

There is also glass wool insulation and mineral wool, however, these options are initially intended to reduce heat loss and prevent the creation of condensation, and not to protect against corrosion, which is why they are used primarily for insulating pipelines of heating networks.
The thickness of the insulating layer can vary. In each specific case, the thickness is calculated depending on the functional load on the pipeline, the importance of the water line and the corrosive activity of the soil in which it is located - the higher this activity, the thicker the insulating layer should be.

Internal insulation

It is advisable to insulate pipes not only from the outside, but also from the inside. For example, in the USA for steel and cast iron pipes previously successfully used internal cement coating thickness of 3–6 millimeters, and this maintained the pipeline capacity for a long time at high level. Can be applied cement-sand mortars, varnishes. In addition, it is possible to deprive the water itself of its corrosive properties through special treatment.

Cathodic protection

Cathodic protection is another method of protecting metal pipelines from corrosion, fundamentally different from those discussed above. It is based on the electrochemical theory of corrosion, according to which corrosion is associated with galvanic vapors that are formed in the area of ​​contact of metals with the soil environment, and the destruction of metals occurs in places where current leaves it. environment. Therefore, if you connect an external source of direct current and direct the current to the ground through old ones previously buried near the pipeline iron pipes, rails and other metal objects, then the surface of the pipeline will turn into a cathode, which will protect it from the destructive influence of galvanic couples. And the current must be diverted from the pipeline through a special wire to the negative pole of an external source. The disadvantage of this method is that it requires energy, so it is often used as an additional, but not the main method.

Removing water pipes from electric transport routes

Corrosion of metal pipes can be facilitated by the influence of stray currents, which are especially exposed to pipes laid near the tracks of intra-factory or urban electric transport. This can be avoided in two ways - by removing water pipes from electric transport tracks and adhering to the well-known rules for constructing rail roads for electric transport.

Listed protection methods water pipes against corrosion are usually used in combination. These methods summarize the experience of many years of practice and various technical studies, so their effectiveness is not only proven, but also tested by life.

Of the different types of posts used to build a fence on summer cottages, in most cases pipes are used. Firstly, the material is from a moderate price category, durable, easy to use. Secondly, it combines perfectly with other materials.
Depending on the type of barrier, they are selected different kinds pipes Use round, rectangular and square. Round ones are a little cheaper, but square or rectangular ones are stronger and easier to work with.
Painting fence posts will not only give aesthetic appearance fencing, but will also protect the pipes from corrosion. Regardless of whether the material was used or new, the preparation requirements are the same.
To pre-treat pipes you will need:

• metal brush;
• brushes for power tools;
• grinding wheels;
• sandpaper;
• personal protective equipment.

The treated surface is thoroughly cleaned of rust and dirt. A suitable tool for this purpose is selected. For removing old paint washing may be necessary. The stores offer a wide range of removers for old paint.

Bitumen mastic

Bitumen mastic is widely used in various construction work both protective and waterproofing material. In the case of support pillars, it is necessary to process that part of the pipes that will be buried or cemented. This will help protect the metal from water and salts dissolved in it.
Paint support pillars for collection is possible before installation. At the same time, the drying time increases, since the lower plane is not painted, but work with round material It's just difficult. In addition, the finished surface can be damaged quite easily. Therefore, it is better to apply paint after installation.

If it is planned to conduct welding work, then the coating must be applied after finishing them, carefully cleaning the welding seams!

Bitumen varnish

The prepared pipes are degreased with an available solvent, and varnish is applied to the surface with a brush. The use of varnish does not require additional primer. If the varnish is too thick, it is diluted with white spirit. When purchasing bitumen varnish, you need to pay attention to the drying time. It can range from 1 to 48 hours.
Due to its high adhesive properties it can be used as self-covering, and act as a primer.

Paint treatment

When choosing paint, the main thing is to decide on the color scheme and buy material from one manufacturer. This will guarantee that the color scheme will not change. In case of special wishes for color, you will have to use different types. When purchasing for mixing, consultation with a specialist is necessary, since not all paints can be mixed. They can curdle like milk, which can ruin the whole process. And since we are talking about a dacha, here we are talking about more economical options.
When painting, oil, acrylic, alkyd and other paints are used. It all depends on your wishes: a matte or glossy finish will be the final product.
Oil paints are considered the most economical, but have a number of disadvantages: they take a long time to dry, do not withstand high temperatures, poorly protect against corrosion.
Enamels harden faster, hold better and are more resistant to temperatures.

The ideal option would be acrylic paints. They are non-toxic, water soluble, and can withstand high temperatures.

Before painting, the metal surface should be primed. For this purpose, GF-021 or similar ones are most often used. Its color is gray and red-brown. To reduce the amount of paint used, a more suitable primer is selected. It is applied to a dry, clean surface with a brush, roller or using a spray gun in 1-2 layers.
After the primer has dried, begin painting. To prevent the primer from showing through, the paint will have to be applied in two layers.

Paint "Special Forces"

A clear minus of this product- high price. In all other respects, it is ideal for working with metal surfaces. This is a three-component paint. It contains a rust converter, a primer and the enamel itself.
When working with Spetsnaz, there is no need to apply primer or heavily clean the supports. However, although it is written that it is applied to rust, it is better to remove it. Degreased with either white spirit or solvent 647.
Paint is applied to the cleaned pipe with a brush. After the first layer, there may be unpainted areas, but after applying the second, there will be no such areas. For exterior use three coats are required. “Spetsnaz” dries quickly, therefore, being in an open jar for a long time, it begins to thicken. It is diluted to the desired consistency with the same white spirit.
The enamel is packaged in 900 g jars and comes in ten colors. After drying it takes on a matte finish.
Now there are many names of three-in-one paints: “Rzhavostop”, “Nerzhamet”, “Hammerite” and others. What they all have in common is application to a rusty surface. Although, to clear your conscience, it is better to clean up. And the price range is not cheap.
Although these types have their own advantages, many prefer a primer with or without subsequent painting.
For painting pipes, they also use aluminum silver powder, which is dissolved in varnish for exterior use.

General rules for painting work

In order to successfully complete the planned work, you should adhere to certain rules that can protect you from annoying mistakes.

1. Since most of the materials used are flammable, work should not be carried out near open flames.
2. For painting, you should choose a dry, warm day, since the quality of the layer deteriorates in strong sun.
3. If you have any doubts when purchasing, ask for a product certificate.
4. Use covered clothing and gloves to protect your body from paint.
5. Keep paints and varnishes and solvents should be kept away from direct sunlight and sources of fire.

By fulfilling these simple requirements, the fence will serve for a long time and will not require frequent repairs.

Under its influence, the metal of the pipes is destroyed, which leads to the formation of corrosive fistulas, cracks in bends, and divergence of seams. Cold water pipes are especially affected. If your immediate plans do not include replacing the pipes in your apartment with stainless steel ones (galvanized, plastic, metal-plastic), then you need to take measures to protect the pipes from corrosion.

The most common (and also the simplest) way to protect metal surfaces from rust is to coat them with anti-corrosion compounds. Cold water pipes can be primed ready-made compounds GF-021, GF-032, KF-OZO, PF-046, FL-053, EP-076 and HS-068. Beautiful protective agent can also be prepared at home. Mix 150 g of red lead, 150 g of red lead and 100 g of drying oil and cover with the resulting composition steel pipes.

A good protection against rust is to paint pipes; the main thing is that the paints and varnishes are moisture-resistant, and the paints intended for painting hot water pipes are also heat-resistant. Before painting, it is recommended to prime the surface with lead-lead or similar primer.

If certain sections of pipelines are laid hidden, then it makes sense to select more reliable means of protection for them.

An effective, but rather labor-intensive way to protect pipelines from corrosion is the following (it is applicable only if the pipes have not previously been coated with any compounds; it is rational to carry out such protection at the stage of laying the pipeline). If there is rust on the pipes, clean it off and cover the pipes with a mixture of casein glue and cement. When the casein solution has dried, dry the pipes and coat them with oil paint.

Coating pipes with carbonate not only prevents the formation of condensation, but also protects them from corrosion.

Steel outlet pipes and cast iron siphons can be treated with one of the following compounds to protect against corrosion:

• bakelite-aluminum - combine 1 part by weight of aluminum powder and 9 parts by weight of bakelite varnish and mix well;
• ethinol-aluminum - combine 0.7 parts by weight of aluminum powder and 9.3 parts by weight of ethinol varnish and mix well;
• ethinol-glue - combine 1 part by weight of BF-2 glue and 7 parts by weight of ethinol varnish and mix well.

Not only steel pipes, but also parts made of other metals are susceptible to corrosion, so it is recommended to protect all corroding pipeline elements from rust. Thus, on chrome surfaces under conditions high humidity a rusty rash may appear. Its formation helps prevent unvitaminized and unsalted fish oil. If the weather is hot in summer and the room is well heated in winter, then chrome surfaces are treated every 10-15 days. Wipe the chrome parts with a swab soaked in fish oil, and after a while wipe them with a dry soft cloth. Before the next treatment, remove any remaining grease from the previous treatment with a soft rag moistened with gasoline. This simple measure allows you to protect chrome surfaces from rust for several years.

If rust has already formed on nickel-plated or chrome-plated surfaces (for example, on faucets), rub the rusty areas with a rag soaked in heated vinegar to remove it. You can also remove rust from nickel-plated parts using fat (animal or fish). Apply a layer of grease to the rusty stain and leave it for several days, after which remove the remaining grease with a soft rag moistened with ammonia.

The following composition will help free chrome coatings from rust: dissolve 200 g in 1 liter of water copper sulfate and 50 g concentrated of hydrochloric acid. Soak a cloth swab in the resulting mixture and rub it rust spots until completely removed. To neutralize acid, wash surfaces, then rinse clean water and wipe dry with a soft cloth.

Yellow “rusty” stains on the surfaces of bathtubs, sinks, sinks and shower trays can be removed with slightly salted, heated vinegar.