How to clean rust from a metal pipe at home

cleaning pipes from rust Despite the fact that metal-plastic pipes have many advantages, many prefer to use metal ones. One of the main disadvantages of this type of communications is that rust forms on their surface. Plaque impairs the efficiency of communications and also contaminates the supplied water. To avoid this, you need to take care of regular cleaning of communications. First, you need to decide what kind of cleaning you are going to do - internal or external; the choice of the appropriate method or product depends on this. If chips or a thick layer of rust are found on the surface, the communications will have to be replaced with new ones.

We recommend

STEEL PLUS - Rust remover. Designed for instant chemical cleaning and rust removal from any surface. Without phosphoric acid.
Fast acting (4-8 min.) More details

How does corrosion in pipes appear and what does it lead to?

With an increase in water temperature for every 10 °C, its ability to cause corrosion doubles and the ability to dissolve salts CaCO3 and CaSO4 decreases, which leads to accelerated scale formation.
However, it is not only reactions between various chemical elements that cause damage to heating systems. Substances that are dissolved in any water have the ability to settle and attach to the walls of watercourses.

These chemical processes contribute to the formation of rust and scale in the heating system, which reduces the clearance of pipes and their heat transfer.

A corrosion inhibitor is used to prevent or slow down corrosion processes in heating systems. To reduce scale formation, various additives and reagents are used.

Helpful information

Tips to help clean pipes from rust efficiently and safely:

to prevent chemical compounds from damaging the walls of the pipe, they should not be left inside longer than the time specified in the instructions;
after cleaning is completed, the treated surface must be rinsed with sufficient water;
preventive cleaning must be carried out at least once every 3 months;
When working with chemical compounds, it is necessary to use personal protective equipment: a respirator, a mask and rubber gloves.

Sodium hydroxide

Lye is one of the most effective products in the fight against rust. To clean rust stains from plumbing fixtures, you can use alkaline detergents. They are applied directly to the stains and left for about 20 – 25 minutes to work. If the size of the smudges is too large and ordinary household chemicals cannot cope, it is recommended to use active alkali - caustic soda. In a saucepan with boiling water (2 liters), dissolve 50 grams of caustic soda. The resulting solution is poured onto the rust stain and left for 10 minutes. Such products remove rust without mechanical impact and are unable to damage surfaces.

The best store products

There are compositions on sale for removing rust from both the inside and outside of the pipe. Top 3 effective remedies:

Prosept. Concentrated thick product for removing rust from the inner surface of pipes. One cleaning will require 350 ml of gel. Exposure time – 2 hours. Price for 1 liter – 158 rubles.
Chistin gel . The product is used to remove rust and blockages in pipes. The gel is poured into the sewer in an amount of 250 ml, left for 15 minutes, and washed with a powerful stream of water. The cost of 0.5 l is 45 rubles.
Converter with Zinc Fill Inn . This product can cope with a layer of rust up to 100 microns thick. It can be used to process the outer surface of cast iron, steel and other metal pipes. The cost of a 0.4 liter package is 164 rubles.

Consequences of clogging

Regardless of the source of the blockage in the heating pipe, the outcome is almost always the same:

after a certain point the pipes become clogged;
the movement of water in the pipes decreases and later even the water pump will not be able to pump water through this system.

The situation is much worse with thermosyphon heating, where there is no such pump. As a rule, once clogged, heat is not allowed to pass through and the pipes remain cold. And this is only part of the problem. In addition, the boiler itself begins to heat up very much, which can lead to its breakdown.

Some owners carry out annual cleaning of blockages in such a system by changing the water. In other words, the old unclean, rusty water is drained and filled with new water. And this is reasonable, because when the old water is drained, a small amount of chips and rust leaves it. But there is also the opposite side. For rust to occur, iron and oxygen are required. If the pipe is metal, then there is always iron in it, but oxygen is contained in the water. As a rule, when you do not change the fluid in the heating system for a long time, the oxygen content in it decreases significantly, which means that the rusting process stops. With a constant change of water, on the contrary, it is activated. To summarize, we can say one thing - this method helps to get rid of a small amount of rust, but, on the other hand, we only accelerate the new process of its formation.

How to clean internal pipes

To remove various deposits from plumbing or heating systems, internal pipe cleaning is performed. Many experts recommend carrying out preventive cleaning and flushing of pipes to remove scale and rust at regular intervals.

Currently, there are several methods aimed at increasing the throughput of pipes, with the help of which it will be possible to carry out preventive and cleaning measures:

hydraulic shock;
using special chemicals;
using sandblasting;
using abrasives.

Cleaning pipes with water hammer

Using this technique, high-quality cleaning of water and heating pipes from rust and scale is performed. Only specialists should perform such work. They also use appropriate equipment, through which rust is removed from internal surfaces. It is connected to the system, after which compressed air is released into the pipes.

Being under high pressure, the air flow most effectively removes any contaminants. Thanks to water hammer, there is no need to dismantle all communications, so cleaning activities can be carried out under any weather conditions and temperature conditions.

When carrying out these activities, you must comply with safety rules, which are regulated by relevant regulations, so it is better to entrust such work to professionals.

Using this device, a hydraulic shock is applied

Internal pipe cleaning using special products

Since during the active operation of pipes, rust and scale accumulate on their internal surfaces, which significantly reduces their throughput and also has a negative impact on water quality, some specialists clean communications using special means (citric acid, chemicals). With their help, pipes are cleaned of scale in communications of any length.

Cleaning pipes using chemicals

Chemical elements can, if used incorrectly, damage the integrity of pipes, so they must be used in full accordance with the instructions.

Cleaning the internal surfaces of pipes using sandblasting techniques

Cleaning the inner surface of pipes from scale, rust and other contaminants can be done by sandblasting. This procedure is carried out under controlled pressure using a continuous air stream mixed with abrasive. To apply this cleaning method, it is necessary to dismantle the heating or water supply lines, which is very problematic when they are located in hard-to-reach places.

However, for small layers, hand guns equipped with a sand tank are available for sale. It is worth noting that they will not be able to cope with serious deposits.

Devices for cleaning pipes with sandblasting – professional and manual

Cleaning the internal surfaces of pipes using abrasives

This method involves adding special abrasives to the water flows passing through pipes, which remove rust and other deposits from internal surfaces, and is essentially an analogue of sandblasting.

It has its advantages and disadvantages:

high abrasive consumption;
it takes a lot of time to complete the work;
As an abrasive, it is necessary to use special materials that have certain parameters.

Special powder for abrasive pipe cleaning

Before cleaning pipes from rust, you should decide on the methodology according to which these activities will be carried out. Some experts also use devices such as cables for these purposes, the diameter of which is an order of magnitude smaller than the pipes. The movement of the cable along the communication is carried out using an electric or pneumatic drill.

Cleaning the pipe outside

If a pipe is damaged, it is still quite possible to correct the situation from the outside. How to clean a water pipe from rust in this case?

To do this, there are the following methods for eliminating corrosion:

Mechanical . To do this, you will need sandpaper, a spatula, and a regular abrasive (for example, a metal kitchen sponge). Cleaning is carried out by simply wiping the pipe: if we are talking about a thin layer of corrosion, then it is removed quite simply. Next, the cleaned surface is washed with soapy water. As for the method of painting a pipe for rust, practiced by some, this will only hide from visual observation the process of rotting of the pipe, which will continue in the future.
Acid . Vinegar or citric acid can be found in every home. To prepare the solution you will need equal proportions of these substances. To apply the mixture to rusty areas of the pipe, use a brush or sponge. After waiting about three hours, the smeared areas should be washed off with warm soapy water. If after this procedure complete removal of corrosion does not occur, the following method will come to the rescue.
Alkali . There is also no need to run to the store, since all the necessary ingredients are available in any household. Take two tablespoons of soda and dilute them in 1/3 cup of warm water. After the soda has dissolved well, the finished paste is applied to the rusty areas of the pipe. Before doing this, it is advisable to clean the pipe mechanically. To wash off the soda, add a few drops of vinegar to warm water, which makes it possible to completely remove soda deposits. The holding time after applying the alkaline paste is no more than 20 minutes, in order to avoid damage to the pipeline surface by a caustic substance.
By special means . There are quite a lot of anti-rust products on the shelves of construction stores, both preventive and cleaning. During use, you should strictly adhere to the attached instructions. No experiments should be carried out with such substances, since the alkali they contain can seriously damage the metal.

After cleaning water pipes from corrosion is completed, they are treated with a special primer mixture containing anti-corrosion components. This primer can also be used after mechanical cleaning is completed. It is important to ensure that the liquid contains a rust converter, otherwise all the work done will be in vain.

Choosing a quality product for flushing the heating system

Today, the domestic market offers many special products for flushing heating systems, however, not all of them are of high quality.

By choosing a low-quality reagent, you risk not only not getting the proper result, but even harming your pipes, since some components can cause significant damage to their surface.

When purchasing a composition, you need to make sure that the manufacturer has a good reputation and be sure to check all the necessary quality certificates. If they are present, you can rest assured that the cleaner will certainly show good efficiency and will allow you to get rid of rust and sludge in one treatment.

Such products usually contain acid and special inhibitors that prevent etching of the metal and, as a result, the formation of corrosion on it. They will not only wash the pipes, but will also reliably protect them from rust for a long time.

How to protect the surface from the formation of rusty deposits?

To prevent pipes from rusting and rotting on the outside, they are coated with special primer compounds, for example:

FL-053,
GF-032,
PF-o46, etc.

Corrosion can be prevented by coating with enamel or paint. In this case, you need to monitor the quality of the applied layer and update it regularly.

There are no specific ways to protect the inner surface of pipes from rust. To prevent them from rotting, you need to wash them once every 2 months with special store-bought compounds or weakly concentrated acid solutions.

We recommend

DOCKER THERMO is an effective solution for flushing heating systems. Recommended for treating boilers, high and low pressure boilers, condensers, heat exchangers, pipelines, and for flushing household water heating appliances. The selectively active composition of the substance allows you to flush systems not only with metal, but also with plastic or rubber tubes. Concentrate.

Photo: Bosch. To ensure long-term operation of the heating system, it is necessary to carry out regular maintenance. In addition to checking the pressure, you should also monitor and, if necessary, adjust the pH value of the water in the heating system

Among all the dangerous phenomena, the most “popular”, perhaps, is scale loss - this is the name given to a solid insoluble precipitate of calcium, magnesium and some other metal salts. It is formed as a result of heating tap water to 60–65 ° C, in which these salts are contained in the form of ions. All parts of heating and hot water supply systems that come into contact with water can suffer from scale, but the most intense sediment is formed on the heating elements of storage-type electric water heaters. They are the ones who need additional protection. Most storage devices are equipped with a magnesium anode, which, gradually deteriorating during the oxidation reaction, protects the heating element from scale formation and the tank walls from corrosion.

Photo: Buderus. To prevent corrosion of the boiler, the gas combustion air must not contain aggressive substances. Halogenated hydrocarbons, chlorine and fluorine compounds promote corrosion.

If the magnesium anode is severely worn, it must be replaced. The condition of the rod is assessed visually during an annual service inspection. Typically, the anode is supposed to be replaced every 1–2 years, so when purchasing it is worth checking where you can purchase the part and how exactly it needs to be replaced. However, models of water heaters with a titanium anode connected to a protective current source (“with superimposed current”) and do not require replacement are now widespread.

As for heating systems of country houses, in well-equipped closed circuits in small volumes of circulating coolant (several tens of liters) the danger of scale formation is low. And in order to avoid it, it is enough, as water enters the house, to carry out its general preparation, aimed at reducing hardness, reducing the content of calcium and magnesium ions (we discussed this in detail in the article “Water - and nothing extra,” No. 1/2015. ). Another thing is communal boiler houses, where there are significantly larger volumes and constant leaks that have to be compensated. In such cases, both additional softener filters in the water make-up system and magnetic water activators, which are popular today, can be used.

Photo: De Dietrich. Titan Activ System kit (De Dietrich) consisting of a titanium anode with superimposed current and a power supply. Its advantage is that the anode is not consumed during operation

A much greater danger for domestic heating systems is corrosion of the metal of the heating installation. It can occur due to oxygen entering the heating system from the air. Possible ways for oxygen to penetrate are leaks in the heating system, vacuum zones, an expansion tank of insufficient size, or plastic pipes without a protective layer. It is difficult to combat corrosion; it is much easier to ensure the tightness of the system in advance by correctly designing the circuit and using pipes with a protective layer.

Corrosion damage usually occurs in cases where oxygen constantly enters the heating circuit water. To avoid this, the heating installation must be closed. In cases where it is not possible to create a closed system, special measures must be taken to protect against corrosion when treating water used for heating. In addition to filling the heating system with demineralized water, special chemicals can also be added. They bind free oxygen or form a film on the surface of materials that protects against corrosion. In addition to checking the pressure, you should also monitor and, if necessary, adjust the pH value of the water in the heating system. It should be between 8.2 and 9.5.

Sales support engineer, Bosch Thermotechnics

Importance of Cleaning

Rust is a red-brown deposit on metal that forms after oxidation and leads to the destruction of the material. Spots on the surface appear for various reasons and can cover large areas. It is important to prevent their spread as soon as the problem is discovered.

Corrosion often occurs on pipes in the basement, but in an apartment this problem is no exception. Plaque is dangerous in places of various connections, that is, at joints where there are taps or meters for measuring water. If you do not notice the appearance of corrosion in time, then later you will have to replace part of the pipe with instruments and components.

Recently, homeowners have begun to replace iron pipes with metal-plastic ones. At the same time, many people still use iron ones, and in this case the problem of getting rid of corrosion on the outside of the pipeline is acute.

Rust occurs on the walls with frequent or constant contact with water. This spoils the appearance of the pipe. Over time, corrosion covers most of the surface and enters the metal structure, which leads to thinning of the walls. As a result, a huge amount of rusty particles accumulate, which move further along the water supply and become compacted. Soon the communication gap narrows to such an extent that because of this, the flow of water is significantly reduced or stops altogether.

Under the influence of rust, the pipeline coating is destroyed over time, and the strength of the metal walls decreases. In especially thin places, gaps appear, due to which leakage occurs. In this case, cleaning will no longer give the desired results. It will be necessary to dismantle communications and replace the pipeline with a new one.

Before starting work to remove contaminants, it is necessary to assess the extent of damage to the pipe.

If the coating has penetrated deeply, it should not be removed, as you may simply accidentally puncture the pipeline. But even if the plumbing is not badly damaged externally, it is recommended to clean its walls from time to time to prevent rust.

Unscheduled cleaning of communications is carried out in a situation where the following is noticed:

stains on a metal surface;
low water pressure in the water supply system at the facility.

Features of the use of inhibitors

Specially developed reagents for heating systems have the following features:

Protect all types of metals from corrosion;
Reduce the adhesion of water-soluble components;
Prevents the formation of sediments of insoluble substances in the heating system;
Designed for use at temperatures above 100 °C;
The period of effective protection is 5 years;
The regent should occupy 2 - 2.5% of the total volume of coolant in the heating system. This significantly reduces the cost of protecting heating systems;
Additives contain volatile substances that, when evaporated from water, create a protective layer on surfaces that do not come into direct contact with the coolant;
Additives do not contain harmful substances;
Slows down the development of bacteria and algae.

Fighting rust

To prevent rust from ruining the heating, you need to prepare the system for startup in advance.
For this purpose, you need not just pour water into the pipe, but add special antifreeze to it. Its effect is the same as in engine fluid, that is, it guarantees good heat transfer through the pipes, and also forms protection for metal surfaces from oxidative processes and prevents the occurrence of lime deposits and other deposits. This alternative is quite expensive, but it makes it possible to forget about constant cleaning. The entire cleaning stage is relatively simple and does not require the use of complex techniques. The process will proceed as follows:

pipe cleaning;
cleaning the heating boiler itself.

Pipe cleaning

The easiest method of cleaning a heating system is to use chemicals.
All we need is to buy a product that can dissolve rust and other types of deposits. A similar remedy can be ordinary citric acid, which every housewife has. It must be dissolved in water, it is advisable to use a three-liter jar, since a large amount gives a greater effect. This entire solution must be poured into the heating system. Subsequently, you immediately need to light the boiler, set the temperature to a high level, and wait twenty-four hours. Later we drain this water. We flush the pipes by filling and re-draining clean water.

Another similar technique is the use of food vinegar. To achieve the best effect, you need a lot of it. But there is also a more win-win option - using hydrochloric acid, preferably 10 or 20%. This chemical is excellent at cleaning pipes. But you need to be careful with this substance, since too high a concentration can significantly damage the heating system.

This operation is only suitable for small blockages. If the pipes are thoroughly clogged, then a compressor will help out. Most often, this method is called hydropneumatic cleaning.

The process will proceed as follows:

connect the compressor to the heating system;
connect the compressor to the pipe and start it up;
flushing begins by simultaneous combination with pneumatic shocks;
disconnect the pipe going into the boiler (from below);
We place some container near it so that dirty water flows into it;
Clean water must constantly flow into the riser (while draining unclean water).

The compressor is expensive and if you don’t want to spend money, you can dismantle the radiators (each separately). That is, they are washed under enormous water pressure.

Boiler cleaning

There may also be deposits in the boiler itself. In addition, there are more of them here than in pipes. The fact is that it heats up very much, which speeds up the process.

Chemicals are used here. The whole job is quite simple: you need to disconnect the heating pipes, take a pump, which is combined with the boiler and water is let in through it, with chemicals added in advance. We drain all dirty water and then rinse with clean water.

Having mastered all the tips discussed, you will be able to flush the heating system yourself with complete confidence.

Due to the nature of their operation, heating pipes and radiators constantly have to come into contact with water. And, as you know, metal, when interacting with a liquid, is prone to oxidation and, as a result, the formation of rust.

Corroded areas can gradually cause leaks. But first of all, this phenomenon is fraught with a decrease in heat transfer of the entire heating system as a whole.

Together with lime deposits, rust clogs the passage of pipes and creates a coating on their inner surface that prevents normal heating of the room. At the same time, fuel consumption does not decrease, but rather only increases. That is, you spend more money on heating and still do not get the desired result.

Based on all of the above, it follows that it is extremely necessary to take timely care of how to flush the heating system from rust.

When to clean pipes

Corrosive changes can also occur in heating systems. When they appear, the efficiency of space heating will significantly decrease, and operating costs will greatly increase. The advisability of cleaning depends on the extent of the damage:

Cleaning pipes in areas that are heavily rusted is not advisable, since during this procedure the pipe can be damaged. The best solution would be to completely or partially replace the pipes in the system so that it can continue to be operated with maximum efficiency.
In the event that minor accumulations of rust and scale are detected, a number of cleaning measures can be carried out and the pipes can be returned to their previous performance characteristics.

Why do you need to clean pipes from corrosive deposits?

Rust affects not only the fact that in places where plaque has formed, the pipe can simply leak, but also the quality of the transported liquid. Water in rusty pipes has an unpleasant odor and becomes suitable only for technical use.

Corrosion in heating pipes reduces heating efficiency, which inevitably increases operating costs.

We carry out external rust removal

The outer part of the pipe usually suffers only from rust. You can remove an unwanted problem using the following means:

Fine sandpaper. This manual cleaning process is quite labor-intensive, so it should only be used on small areas. A sheet of “sandpaper” is wrapped around the desired section of the pipe, hands are protected with gloves and, covering the pipe, they move from side to side.
Brush. You can use a brush with metal bristles or put a cable brush on the angle grinder.

A suitable brush should have a spiral cable weave

Special chemicals. There is a wide range of corrosion converters and rust modifiers on the market. The principle of their action is often to convert corrosion products into compounds that are safe for metals.

“Tsinkar” is the most well-known remedy for combating external rust.

Selection and recommendations for using an inhibitor for a heating system

This or that inhibitor must be selected based on several indicators:

1An open or closed type expansion tank is used; 2Type of construction materials used: ferrous metals, alloys based on copper or aluminum; 3 Water pH indicators; 4Indicators of water “hardness” (the amount of dissolved salts in the coolant).

Depending on the hardness and acidity of the coolant, as well as the characteristics of the heating system, it is necessary to select an inhibitor of a certain composition. The following additive compositions are distinguished:

Orthophosphate. The reagent forms a protective film and causes the precipitation of salts in large quantities. It is necessary to add to the coolant based on the proportion of 10 - 20 mg/l. Used in heating systems where the elements are made of ferrous metals and the pH level of the water is less than 7.5 units. A chlorine concentration in water of 300 mg/l or more neutralizes the effectiveness of orthophosphate and leads to metal corrosion. Can be used in combination with a zinc polyphosphate or phosphate additive;
Polyphosphates. Used to protect pipelines made of ferrous metals with water Ph in the range of up to 7.5 units. When using polyphosphate, water softening is not required. The amount of chlorine also does not affect the properties of this inhibitor. The effectiveness of polyphosphates is increased with the help of zinc. The optimal amount is 10 - 20 mg/l;
Phosphonates. Use only in combination with zinc, orthophosphates or polyphosphates. The composition will be effective at a concentration of 10 - 20 mg/l and at Ph 7 - 9. Protection of ferrous metals is ensured by the addition of calcium;
Molybdate The reagent protects ferrous and aluminum alloys. It is necessary to add to the coolant at the rate of 75 - 150 mg/l; in order to reduce the amount of the composition without reducing efficiency, the addition of phosphorus components is required. Recommended pH of water is 5.5 - 8.5. Hard water causes molybdate to precipitate. Chlorine and sulfur impurities neutralize the use of molybdate, but without the occurrence of pitting corrosion;
Silicate. Used for soft water at a concentration of 10 – 20 mg/l. Provides protection for systems made of ferrous metals and copper alloys with water having a Ph 7 or higher. A protective coating forms on surfaces over several weeks;
Zinc. It is used as an additive to other additives: orthophosphates, polyphosphates, phosphonates, molybdates. And also with combinations of inhibitors that do not contain zinc: orthophosphate/polyphosphate, orthophosphate/molybdate, a mixture of phosphonates in an amount of 0.5 - 2 mg/l. Zinc strengthens the protective film and allows you to reduce the amount of the main inhibitor. If the pH of the water exceeds 7.5, it is necessary to use zinc stabilizers;
Benzotriazole. The required concentration is 1 - 2 mg/l in water with Ph 6 - 9 to protect copper alloys;
Tolytriazole. Benzotriazole analogue;
Calcium orthophosphate. Used to eliminate the adhesion of calcium phosphate deposits. The content of calcium orthophosphate in water should be 10-15 mg/l;
Polyacrylates, polymaleates, hydrolyzed polyacrylamides and acrylate substances. Used for biological contamination. The optimal concentration is 2-3 mg/l;
Chlorine and bromine are used to destroy microorganisms. A concentration of 0.1 - 0.5 mg/l is sufficient. Chlorine is effective only in water with a pH below 8. If the pH exceeds this value, bromine is used;
Zeolites. Used to soften water;
Nitrite. Used in closed systems, it causes the formation of a stable film of iron oxide on the surface. Effective in concentrations of 250-1000 mg/l and increasing Ph to 9 - 9.5 by adding borax. The amount of nitrite can be reduced to 300 mg/l if molybdate is used in the same amount. Nitrites can be decomposed by bacteria, so in combination it is also necessary to use a non-oxidizing bactericide, copper corrosion inhibitors and a polymer dispersant;
Alkalis (caustic soda, ash). Used to increase the pH of water to 9 - 10.5 units.