Cold welding for heating under pressure

Repair of polymer pipes

Briefly about cold welding

If the entire block is not needed, cut the required amount crosswise with a knife.

Any person at least once in his life has been faced with the need to repair radiators, pipes, expansion tank and other components of the heating system. Even twenty years ago, any heating circuit and batteries in it were repaired only by hot welding. Today, the modern market offers a quick and effective way to eliminate leaks and holes in any piece of heating circuit equipment. In this case, you no longer have to use welding at elevated temperatures. Well-known methods have been replaced by a new technology - cold welding for cast iron batteries, bimetallic and aluminum radiators, plastic and steel pipes of the heating system.

Cold welding - what is it, application for heating system

The technology of gluing metals has been used since ancient times; as a result, permanent connections were created without the risk of oxidation of parts. Cold welding is understood as a technological process of joining products without additional heating, as a result of which their surfaces undergo plastic deformation. The latter destroys the film of oxides, which previously prevented the metals from joining. Welding occurs in a short period of time as a result of setting. In appearance, this adhesive composition resembles putty and is made on the basis of epoxy resin.

Cold welding is now widely used to join the following metals:

Using welding glue, you can repair steel and aluminum batteries, cast iron radiators, and bimetallic radiators. Polymer products for pipelines can also be welded in this way. We are talking about propylene pipes, which are used for installing a heating system. If the technology is strictly followed, it is possible to seal a pipe, riser, or radiator with any defect, although the strength of the joint will be somewhat inferior to that after electric arc welding.

What and why can break in the radiator

Cast iron tolerates the alkaline coolant environment well, is slightly susceptible to corrosion and has high mechanical strength. Heating devices have a simple design and are very durable, so breakdowns due to simple metal wear are a rare occurrence. A striking example of a potentially possible service life is working pre-revolutionary batteries that have been preserved in the homes of some St. Petersburg residents. But cast iron batteries also have weak points; it is in them that the “root of evil” lies.

The most common causes of battery problems

Heavy weight, bulky

Cast iron batteries are large and heavy, which becomes a problem during installation. The slightest flaws in the installation can lead to malfunctions during operation. If you do not take care of a sufficient number of powerful brackets, the batteries may become distorted over time, which will also lead to negative consequences.

Insufficient resistance to high pressure and water hammer

Cast iron has good technical and operational characteristics, but the load that domestic heating networks can create may be too great. Due to water hammer, leaks are possible at the junctions of sections.

Dirt and trash

Along with hot water, foreign impurities, small particles of dirt and rust circulate through the pipes, which leads to blockages in the internal channels. Batteries must be washed promptly, otherwise malfunctions in their operation are inevitable.

Wear of intersection gaskets and threaded nipples

Joints are always a “risk factor”. Nipples and gaskets last much less than cast iron. They need to be replaced periodically. After this, you can forget about heating problems for a long time.

Signs of a broken cast iron radiator

The room doesn't warm up well

If during the heating season the room temperature is lower than usual, check how things are with your neighbors. If they have no complaints, it's time to tackle the heating. Perhaps regular flushing of the channels will solve the problem.

There is a coating on the radiator

It usually forms at joints. The reason is the low quality of the coolant. When the gaskets wear out, they leak fluid. After drying, a residue similar to scale remains.

The most obvious sign of malfunction is the appearance of leaks. Repair involves sealing and applying a metal clamp. If there are several leaks in the radiator, it is better to replace the device.

Cold welding composition

Adhesive for metal and plastic is made from epoxy resin, a polymer with high strength characteristics. It is this resin that is responsible for the homogeneity, plasticity of the mass, the ability to seal even minimal cracks and fill holes. Epoxy can thicken only when in contact with the hardener that comes with the kit (in some products it is in solid form and is activated after exposure to air and mixing).

Cold welding contains various fillers that optimize technical properties: steel powder (strengthening additive), sulfur, plasticizers. When repairing radiators, you must definitely pay attention to such additives; they must be in the putty.

Types of adhesives

Many ordinary people doubt the effectiveness of this method of repairing heating radiators.

But, as can be seen from practice, this is not true.

The wear resistance of the resulting seam or joint depends on how correctly the connecting element is selected.

What do you know about the sizes of cast iron heating radiators? Read about batteries in this helpful article.
How you can eliminate leaks at the joints of sewer pipes is written here.
On the page: https://ru-canalizator.com/vodosnabzhenie/avtonomnoe/mufty-pnd.html it is written about electric welded couplings for HDPE pipes.

Systematization by physical content:

fluid mixtures
plastic mass.

If you decide to buy a liquid product, pay attention to the packaging, it should contain 2 tubes. One with an elastic substance, the other with a hardener.

They are mixed immediately before eliminating the leak in the plastic pipe at the junction.

Please note! The mixture must be consumed within 20 minutes, otherwise it will thicken and become unusable.

Plasticine welding for the heating system is produced in the form of a two-layer bar, inside of which there is a plastic substance, and a hardener is on the surface of the bar.

Before use, plasticine should be kneaded well. If you don't need all the material, you can cut it, but only crosswise.

Experts strongly advise using cold welding to restore only those materials for which it is intended.

On the packaging of the composition, the manufacturer always indicates the temperature that the mixture can withstand (in most cases, this is 260 degrees Celsius).

If these parameters are observed, the seam will remain strong for a long time.

There are cold welds on the market that can withstand much higher temperatures (up to 1300 degrees Celsius).

This adhesive is used for surfaces exposed to very high heat.

Positive aspects of use.

Ease of use . The composition can be used by a person who has not previously had any experience in plumbing;
The quality of the resulting seam does not depend on the speed of your actions.
There is no need to use special tools and equipment (read about couplings for connecting HDPE pipes here).
Energy consumption is kept to a minimum.
The material has fire-fighting properties.
Ability to repair tanks containing explosives.
There is no surface tension of the material in the weld area.
Low material cost.

Negative sides.

Using cold welding, only metals with high ductility can be joined.
During operation , the material is subject to deformation.
Using this method, parts of certain shapes and sizes are joined.
In order for the work to be completed efficiently, a large area of metal must be used.
Cold welding is a temporary solution to the problem.

Types of welding

All products belonging to this type are divided into plastic and fluid. The latter are necessarily two-component mixtures - one bottle contains epoxy resin with additives, the second contains a hardener. Plastic masses are sold in tubes, bottles, jars; they can be used to coat a pipe or radiator without dilution. The mass looks like plasticine, consisting of two blocks that need to be mixed together by kneading with your fingers. It is possible to separate a small piece of the mass and save the rest until the next need.

Restoration of cast iron batteries using improvised means

How to repair it depends on where the cast iron battery is leaking. If a small gap has formed at the junction of the sections, then this can be corrected using an ordinary clamp, which is sold on the market and in any hardware store. The clamp has the appearance of a metal structure with two rubberized plates on the inside, which are connected by two bolts to each other. Careful fixation occurs with the help of nuts tightened to the required density.

The rubber gasket is the main element for blocking leaks. By the way, clamps come in all sizes, so it won’t be difficult to choose the right one.

There is another method to repair cast iron batteries at the junction of sections if you do not have such a clamp at hand. You can use a simple piece of rubber cut from an elastic medical tourniquet or a bicycle inner tube. The leakage area must be wrapped in several layers of rubber. You can secure it with wire, wrapping it on top.

Methods of use

To repair pipes, you need to prepare everything you need - the welding agent itself, acetone or alcohol, sandpaper, rags and clamps. The method of sealing radiators varies somewhat depending on the type of welding - liquid or plastic. It is important to choose a suitable product that is suitable for pipes under pressure (metal or polypropylene). Next, you need to prepare and mix the material, and you should work faster with liquid products.

Welding application methods:

simply sealing the defect with a piece of mass, flattened and kneaded with your fingers;
the use of special fiberglass fabrics, threads for wetting with epoxy, followed by wrapping with rubber, wire or without it;
gluing onto a large defect covered with a metal patch.

If the leak is strong, you can make the composition even more durable with your own hands. You need to take any aluminum or bronze part, grind it a little over paper, obtaining metal powder. It needs to be added to the epoxy mixture, which is then used to saturate the turns of thread or fabric.

Methods for repairing cast iron radiators

There are several methods that allow batteries to last not only until the end of the heating season, but also for a couple of years. These include:

If there is a leak at the junction of sections, it can be quickly eliminated using a bandage and epoxy glue. The material is impregnated with glue and wound around the leak. After it sets, you can paint this place to match the battery, but the main thing to remember is that such an “operation” is considered temporary, and it is better to buy and install a new section after the cold weather ends.
If a fistula or crack is detected, a clamp will be required. You can buy it at a building materials store, or you can make it yourself from rubber or tin.
Cold welding for cast iron batteries is the best way to quickly eliminate a defect. This is a special sealant that looks like children's plasticine. It must be thoroughly kneaded and applied to the damaged area. The product sets quickly, is resistant to temperature changes and is quite suitable for quick and temporary repair of a cast iron battery.

Knowing how to weld a cast iron battery using a welding machine with an inverter circuit, you can save the device from leaks for quite a long time.

Temperature indicators of the mixture

Depending on the exact composition and specific manufacturer, the temperature range of welding applications can vary greatly. Most products can withstand freezing, for example, Mastix glue will not lose its properties even at -60 degrees. The overwhelming majority of cheap epoxies only work up to +150 degrees, so they can be used for welding radiators and heating pipes (heating networks usually operate at +95...+110 degrees).

Better quality products can withstand up to +260 degrees, but there are also high-temperature mixtures - they are used even in extreme conditions (up to +1300 degrees). Although there is no point in spending money on purchasing such products, you can buy a simple low-temperature composition.

How to seal a heating radiator

Miraculously, a problem with an aluminum heating radiator arose when frosts hit all over Russia. Moreover, the radiator leaked late at night. I woke up several times at night because the heating radiator was making noise. I also thought that this was not without reason and was very similar to depressurization. Alas, I was not mistaken - in the morning there was a decent puddle under the radiator on the laminate floor. Initially I thought that the problems were related to the faucet, but then I discovered swollen paint on the side of the radiator from under which water was oozing.

It was possible to determine the location of the leak by the swollen paint

After removing the swollen paint with a flat screwdriver, I saw the cause of the leak - two small holes.

Two holes in the left section of the radiator

Most likely, the microscopic hole appeared a long time ago, since just a year ago, a noise similar to a clicking emanated from this battery. I kept blaming Mayevsky's damaged faucet, but even after replacing the faucet, the noise did not stop.

Advantages and disadvantages

The technology allows you to eliminate pipe leaks with high reliability. This procedure is safe to perform, which cannot be said about conventional welding. Other benefits are:

convenience, ease of the technique even for beginners;
excellent seam quality, which depends mainly on the type of material, and not on the speed of work;
no need to purchase special tools, equipment, machinery and expensive materials;
minimum energy consumption;
fire, anti-explosion properties of epoxy;
low cost of repairs;
Availability of cold welding - adhesives are sold in any store.

The technology also has disadvantages. Welding of this type is not designed for too high loads - pressure, high heat. Therefore, if there is a serious defect in a pipe or radiator, it is better to use hot welding or replace the area completely. It is important to follow the preparation measures - otherwise the quality of the weld will decrease. The durability of cold welding is lower than that of standard welding - repaired pipes will not last for many years, but will require new repairs. In fact, such repairs are considered by specialists to be a temporary measure.

Sequence of work

Depending on how serious the breakdown is, the steps to fix it depend. So, if the leak is small, then you can do without disconnecting the battery from the circuit, and for repairs you will need:

Place a container under the breakdown site in case of a breakthrough or an oilcloth with rags to collect water.
The area of the rupture or crack must be cleaned down to the base using a cable or sandpaper. It is necessary not only to remove a layer of paint, but to expose the metal itself.
Degrease the prepared area with some solvent.
If special glue or epoxy resin is used to repair the damage, then strips of thick fabric or bandages will be required. Apply the product to them and wrap several layers around the tear site.
If cold welding is used, fabric is not needed.
A clamp is put on and screwed onto the area captured by the sealant, but it is important to ensure that its clamps are on the opposite side of the leak. For example, a crack has formed on the inside of the radiator, which means the clamps will be on the outside, and vice versa.
If the breakdown is serious and hot water is gushing out of the battery, then you need to call an emergency team, and not try to stop the leak yourself without the necessary tools.

Even the highest quality repairs do not guarantee long service life of the device. Restored cast iron radiators will still have to be replaced, and the sooner this is done, the safer it will be in the apartment.

Types and manufacturers

Typically, cold welding is used when it is not financially feasible to use the hot method or it is difficult. Such situations occur when a minimal defect appears, damage to a dimensional product, or the risk of serious internal stresses in the pipe.

The following types of products can be used for repairs:

universal – used for gluing metal, plastic, stone, wood, glass, concrete and most other materials;
automotive - if the material indicates that it can withstand high temperatures, then it is allowed to be used in pipe repair;
for plastic - usually the heat resistance of such products reaches +260 degrees and above, so they are also suitable for work.

Products marked “for wood” or “for plumbing” are not suitable. They, as a rule, are not heat-resistant, and the quality of adhesion will be lower. It is better to find a specific welding method for working on metal or plastic with a clear indication of the temperature conditions. There are even super waterproof products for working underwater, which can also be used for cold welding.

Domestic formulations are cheaper than imported ones, but are not inferior in quality to the latter. Just don’t take the cheapest welding, it will certainly produce a low quality weld. The most popular means are:

Hi-Gear. A universal adhesive, it is often purchased by car owners to seal elements subject to heavy loads. This glue will help eliminate any leaks in the heating system.
"Titanium". Suitable for any materials, does not deteriorate from exposure to water and high temperatures.

The most common problems and their symptoms

Although cast iron perfectly tolerates the imperfections of the central heating coolant, and the radiators made from it have wide enough channels so that debris does not accumulate in them, problems can arise even with them. And this despite the fact that there is no wear to this metal. The following factors may be to blame for a cast iron battery bursting or a fistula appearing in its walls:

Everyone knows the heavy weight of radiators made of this metal. If during installation of the structure, insufficiently strong brackets were used, or there were not enough of them, over time it may sag under its own weight and tilt. Even a slight deviation of just a couple of millimeters will reduce the efficiency of the device, and if the distortion is not corrected, then after a few years corrosion will appear in the place where the coolant is missing. At first it will look like a small brown spot, which will grow with each heating season until a fistula forms in its place.
The reputation of “long-living” is characteristic of both old and new models of cast iron radiators, but provided that they are installed in the contour of an apartment building no higher than six floors. If the heating network is reliable and does not suffer from strong water hammer, then they can be installed in nine-story buildings. Otherwise, under strong water pressure, the cast iron battery may leak at the joints of the sections. In the event that a cast iron battery leaks during the heating season, you need to know in advance how to repair it. Today there are a lot of sealants that will help the device “hold out” until warm days.
The internal structure of domestic batteries is such that the cast iron from which they are made has roughness that is completely absent in imported analogues. That is why a lot of debris is deposited on the walls over time, which fills the water in the heating network. Suspensions, particles of rust and metals, all settle and make the wide channel so narrow that it is no longer able to easily pass coolant under high pressure. In this case, the structure may burst anywhere, and then you will have to urgently decide how to eliminate the leak in the cast iron battery.
Nipple gaskets and threads are the weak “link” of heating devices . If cast iron does not have a statute of limitations, then the same cannot be said about the parts that make up the battery. In order not to lead the situation to the point where repair of the cast iron battery is required, the connections must be checked after each heating season and the gaskets on them must be periodically changed.

As practice shows, most often it becomes known that something is wrong with the heating system when repair of cast iron radiators is already required. To find out about a problem in advance, you need to listen for “help signals” that indicate the presence of defects.

Instructions for cold pipe welding

First you need to properly prepare the base. To do this, all areas to which the resin will be applied are cleaned of rust, dirt, and old paint. You can sand them down to immediately remove all dirt. You should not try too hard, otherwise deep scratches will remain on the surface. But small abrasions will come in handy - they will enhance adhesion. Immediately before welding, parts must be degreased with a solvent (usually acetone) or washed with detergent. If possible, you need to dry the joints with a hair dryer - heating will improve adhesion.

The glue is prepared depending on the instructions. To produce a liquid adhesive composition, a strictly measured amount of hardener is added to the resin. The lifetime of the composition is also indicated in the instructions, then its polymerization begins. Usually the period is 10-15 minutes or a little more. This time can be slightly extended by cooling the product.

Plasticine-like mastics are prepared by kneading with your hands, after putting on gloves and wetting them with water. The required amount of material should be cut from the rod and the rest should be removed. You only need to cut strictly across, otherwise the ratio of epoxy and hardener will be incorrect. When ready, the color of the mass will become uniform, and it will heat up due to the release of heat.

Repairs are carried out as follows:

apply glue to the future joint, directly into the hole, to ensure the mass penetrates deeper;
the second option is to wind glass fiber or fiberglass, cover it with a liquid composition that has already begun to thicken a little;
smooth the outside of the product with a small spatula or other flat device, slightly moistening it in water;
within a few minutes you can change the position of the mixture;
if the hole is too large, you will have to put a metal patch on it (directly using cold welding);
fix the area for 15-60 minutes, depending on the instructions, using a clamp;
If possible, the joint should not be subjected to intense loads for 1-24 hours, although 1-1.5 hours is sufficient for most welds.

If the repair is carried out in a room with a low temperature, the glue should be rolled into a ball and the mass inside should be allowed to warm up to +40...+50 degrees. The holding time of the ball should not be longer than the life time of the mixture (usually it is not kept for more than 4 minutes). To effectively heat the ball, it must be made with a mass of at least 50 g. It must be remembered that when repairing complex joints and assemblies, it is better to immediately use hot welding or replace parts; a cold joint may turn out to be unreliable.

Security measures

After drying, the material is safe for humans, but care must be taken when working with it. All work is carried out with gloves, avoiding direct contact of the epoxy with the skin. Do not use a food grade knife to cut resin. When contacting the mass, the skin is washed with soap and water.

Repair of polymer pipes

Polymer pipes require specialized compounds.

Regardless of the chemical composition of the material being processed and the nature of the welding used, it is imperative to comply with the conditions and recommendations specified in the instructions.

Cold welding for plastic heating pipes proceeds according to the following scheme:

An obligatory step is to prepare the surface of the material being repaired. To do this, the surface of the pipe ends is treated with sandpaper and then degreased. Roughness on the pipe will increase the degree of adhesion with the adhesive. Greasey contaminants can react chemically with cold weld components and degrade their performance;
determine the correct perpendicularity tolerance of the ends. In the case of pipes with a diameter of 20...40 mm, it should be no more than 2 mm;
measure half the length of the coupling at the ends of the pipes to determine the area of the surface to be treated;
the marks are scraped, that is, a thin layer of material (0.1...0.2 mm) is removed from the pipes, burrs are also removed;
Direct preparation of the adhesive composition consists of mixing the components until a homogeneous mass is formed. In the case of plasticine welding, hands are moistened with water before mixing. The paste will not stick to the skin. The shelf life of liquid formulations lasts no longer than 3 minutes, so you need to act quickly;
the prepared mixture is applied to the surface of the material being repaired or joined. Everything is put under pressure. What force should be exerted on the seam is indicated in the instructions for cold welding.

The repaired pipeline or heating circuit can be used 8 hours after welding.

Repairing cast iron and other types of radiators

Working with radiators is similar to sealing defects on pipes. The surface is cleaned and degreased. You can use alcohol for this purpose, applying it with a cotton swab. Next, take a ball of resin approximately 2 cm in diameter, knead it, mixing the components. Press the resin to the damaged area, smooth it out, and hold it with a rag or clamp.

Usually 30-40 minutes are enough for polymerization, but it is better to use the battery after a day, not earlier. Naturally, the water supply must be turned off before repairs. If you need to remove a fistula, you need to take fiberglass and a liquid solution, wrap the area and seal it securely.

Cold welding is an excellent temporary measure until the end of the heating season. It will help eliminate pipe or radiator leaks quickly and without hassle!

A leak in a hot pipe or radiator is a nuisance, but a leak that starts in a pressurized circuit is an even bigger problem. If a heating pipe is leaking, the problem must be repaired urgently.

Methods for sealing a leak depend on where it occurs:

A seamless or welded heating pipe is leaking;
A leak has appeared at the interface between pipe and battery, pipe and fitting, fitting and fitting;
In the intersection space of the radiator;
In an open area of the battery that is accessible for repair.

Each of these accidents can be eliminated using available means and in different ways, but only in one case - if the leak in the heating radiator or in the pipe is small, and water or coolant flows in a thin stream or drips. More serious leaks can be eliminated using more radical methods, which we will talk about. Anyone who has ever repaired a leak in their heating system knows how much trouble they saved themselves and their family from.

In both large and small leaks, you must immediately turn off the shut-off valve for supplying working fluid to the system. The problem is solved by using the following options:

If the radiator is leaking, then you need to close the shut-off valves at the inlet and outlet of the device. If the radiator has a bypass, then the entire system will continue to operate without stopping; if there is no bypass, then it is better to turn off the boiler to avoid unexpected overheating of the heating system;
If there are no shut-off valves or they are installed, but not where needed, then the heating must be stopped so that the pipes do not remain under pressure, and the leak must be repaired.

Steel pipes with hot water quickly rust, even if they are painted, and this causes thinning of the pipe walls. In the thinnest places, a leak may appear over time and, if it is not eliminated in time, the drops will imperceptibly turn into a trickle.

If a colored spot appears on the pipe, the paint begins to swell, traces of rusty water drips or rust on the pipe are visible, water is dripping imperceptibly, you should not wait in the hope that it will stop on its own. It is better if you find a suspicious place in the summer, with the heating turned off - there will be fewer problems with turning it off and maintaining the temperature in the room during repairs.

The battery is leaking - how to cover up a leaking cast iron battery

The battery is leaking - what to do?

Almost every house and apartment has cast iron radiators, thanks to which it is always warm and cozy in cold weather. The service life is several decades, this is so long that almost everyone takes their work for granted, without thinking at all about the fact that they need to take care of the battery. Of course, when an incident occurs in the form of a leak, everyone begins to cut off the telephone numbers of the housing office and private masters If this happened on a weekend, everything is somewhat more complicated. The average apartment resident has no idea what or how to do if a cast iron battery starts to leak.

Please note that if employees of the management company or heating network, during a scheduled inspection, will be able to identify and fix the breakdown in time, but this must be done on time and in advance.

A breakdown causes a lot of trouble if it happens in winter and there is already water in the system . Below we will tell you how to provide first aid to a battery and not leave your family without warmth and comfort, without flooding your neighbors.

What does the battery consist of?

If we are talking about old-type radiators, then in appearance they resemble accordions, while modern models are flat, due to which they heat up more evenly. Cast iron is a very strong material, but even it does not last forever, it has a limit of stability. So the service life varies from 20 to 30 years, depending on operating conditions. If maintenance is carried out in a timely manner, the service life increases several times and the battery will last almost a hundred years.

Unfortunately, problems often arise in the places where the sections are fastened to each other; they wobble due to water or crack due to age. This is where the leak begins, which is best localized as soon as possible.

Placing a basin or saucepan under a dripping radiator is not a solution, as the crack tends to grow, so that one day a flood may occur! If we are talking about the winter period, then there is generally boiling water in the pipes, which poses a serious danger to the life and health of people.

What breaks most often

Although cast iron is a great conductor of heat, batteries have wide channels which minimize the risk of the battery clogging. In this case, it will heat the room worse. So why might the battery burst? The radiator is too heavy , if the brackets are installed weakly or not deep enough (and it also happens that they are completely forgotten about and the battery hangs on the pipe), over time it sags under the weight of its own weight and tilts. It would seem that this is not the case, but the slightest deviation is fraught reducing the efficiency of the device. If no one paid attention to this and did not correct it, corrosion appears and leaks begin. Initially, corrosion damage appears as a small brown spot that gets larger.

Many people mistakenly believe that older radiators last much longer and work better, but there are also those who prefer newer models. Both will work properly if they are located no higher than the 6th floor.

Provided the water flow is stable and there are no water hammers, in this case the battery will heat and operate at least on the 10th or 20th floor. Otherwise, a leak may form at the joints . Any hardware store has a lot of sealants that will help correct the situation or prevent it altogether.

DIY repair

The inside of the cast iron is rough; if the radiator is foreign-made, then there are no roughnesses. Due to the roughness, debris clings to the walls and settles inside. If the battery is not cleaned, it will clog and simply burst from the high pressure of water. If there is a leak at the joint, then a simple bandage and epoxy glue will help to cope with this, coat the joint with glue and soak the bandage with it, then wrap the joint tightly, wait until the glue sets and once again, sparing no glue, coat everything, then you can touch up the place no repairs were visible. This is a temporary measure; after the heating season ends, it is worth replacing the section.

If a crack has formed , then a bandage and glue will not save the situation; you will need a clamp. It is better to use cold welding, a sealant that is very similar to window putty. Knead it thoroughly and cover the crack with it, after a few minutes everything will set and you can sleep peacefully for another heating season.

All other methods, unfortunately, are useless. Even after such independent repairs, after the end of the heating season, it is worth turning to a specialist for help. Even the best cold welding is not a guarantee that the leak will not return after some time. Carry out technical inspections and minor repairs in a timely manner and let the radiator serve you faithfully.

How to fix a leak in a pressurized water pipe

If a pipe is leaking when the coolant pressure is low, then an ordinary iron pipe clamp to eliminate the leak is a sure and quick solution to eliminating a leak in the heating system. The factory clamp is a round metal structure with a wall thickness of 1-1.5 mm, rubberized on the inside and equipped with a bolt and a nut for tightening (or a pair - depending on the width of the clamp);
People's advice on how to seal a leak if there is no steel clamp: wrap the accident site with rubber from a bicycle tube, a pharmaceutical bandage, or any suitable piece of rubber, for example, a rubber glove. You can secure such a homemade clamp with wire, or wrap it with any cord;
In the absence of a factory clamp and rubber, you can make a homemade clamp from tin, even from a tin can lid;
Even a piece of elastic polymer (for example, vulcan rubber), tightly wrapped with wire, turn to turn, can temporarily save the situation.

Other methods of eliminating an accident if a heating pipe is leaking will not work - only dry surfaces can be sealed with cold welding, although the hardened composite can then work even in water. It will not work to seal a hole or crack with sealing compounds for the same reason - the surface to be repaired must be dry, and preferably clean. Therefore, sealant for heating pipes, epoxy resin, dichloroethane and other fast-hardening composites are used only on disconnected dry sections of the heating route. This also applies to the repair of the water supply line in the water supply pipe for hot water supply or hot water supply.

Elimination of fistula

For any breakdown there are a number of reasons accompanying it. A fistula on heating system pipes or on a radiator is no exception. If a small brown spot appears on the elements of the heating network, you should not think that it is paint coming off. In fact, this is the beginning of an often irreversible process, but knowing how to repair a fistula in a cast iron battery, you can stop the destruction and extend its service life. Causes of corrosion:

Taking into account the frequent increases in the cost of utilities, some craftsmen are cunning and, in order to save energy, connect a neutral cable to the heating circuit. The currents that begin their “journey” through the pipes through the coolant are what cause the formation of corrosion. You can identify a dishonest neighbor if there are several fistulas and they appear with a certain regularity. Calling the appropriate service to identify the intruder and repairing cast iron batteries yourself will help save the situation.
Too much acidity of water can harm even corrosion-tolerant cast iron.
The batteries have expired or deposits on the battery walls have damaged the metal. In this case, even a small fistula or crack under the influence of water pressure can cause the battery to burst and a stream of hot water to flow from it.

In the event that the coolant ruptures the place where the fistula was located, the question immediately arises whether it is possible to weld a cast iron battery . As a rule, cold welding becomes an emergency solution, but even if it has restored the tightness, it is necessary to call specialists from the heating network to check the condition of the heating system.

How to fix a leak in your home heating system

If the leak is strong and a simple clamp cannot be used to close it, the heating circuit with liquid will have to be turned off. It doesn’t matter where the leak is found - on a heating or water supply pipe - eliminating the leak will only be possible by turning off the water supply. A disconnected circuit gives scope for repairs: you can at the same time check the entire route and repair (replace) all suspicious areas.

Let's start with the simplest ways to fix a leak in a heating pipe:

Seal the gap or hole with a fabric (fiberglass) patch liberally coated with epoxy glue. The patches (there should be 2-3 of them) are cut twice as wide as the diameter of the pipe; the length should allow the pipe to be wrapped 5-7 times. The metal around the violation is cleaned with sandpaper, a file or a grinder, the area is well dried, and epoxy resin is applied to it. The fabric can be soaked with glue in advance, or you can coat it as you wind it onto the pipe - whichever is more convenient on the spot. The last fabric layer is not saturated with glue, and the end of the fabric is secured with cord or wire. Epoxy dries on a pipe in different ways: at a temperature of 20 0 C-25 0 C, a few hours are enough; at a temperature below 18 0 C, even a day is not enough.

If you have repaired a central heating pipe, then the system operates under higher pressure than individual heating, and when water is initially supplied to the circuit after the repair, a noticeable water hammer may occur, which can simply rip off the patch. Therefore, the supply valve should be opened slowly, tracking the area with the patch visually.

You can increase the strength of the patch by adding bronze or aluminum powder to the epoxy glue. If you were unable to buy powder, you can make it at home by grinding off the surface of any non-ferrous metal part with a small file or needle file. By adding such powder, you can make not 5-7 turns of fabric, but 2-3, and repairing such an area will become easier and faster.

Factory materials

From ready-made solutions, adhesives and liquids, you can use a heat-resistant, waterproof sealant to seal the leak. Such adhesive compositions are produced specifically for the repair of heating systems. When purchasing, make sure that the word “neutral” is on the label - this means that your glue will not corrode non-ferrous metal and adjacent materials.

Cold welding is also good for eliminating leaks:

A liquid epoxy substance that is convenient for impregnating fabric patches that are applied to a hole in a water pipe. Some compounds can also work on a wet surface;
Semi-solid plastic compositions. This cold welding looks like a small piece of plasticine consisting of two different component strips. Knead the plasticine in your hands until the substance becomes plastic (your palms should be wet - moisten them in water), cover the hole in the pipe with a small piece, and spread it over the cleaned surface. It takes 10-15 minutes to harden, after which the patch becomes so hard that it is difficult to take even with a file.

Both liquid and solid cold welding contain toxins, so it is recommended to use rubber gloves when working with it.

Sealing connections on pipes and between radiator sections

If connections at the junction of pipes or fittings are leaking, then, depending on the difference in diameters, you can immediately seal the pipeline with a metal clamp or first wrap rubber in place with a smaller diameter. The rubber band is easily wound even under pressure, stopping severe leakage.

BF-2 glue works well for sealing the threaded connection in the place where tow or FUM tape is wound. The tow is first soaked in alcohol, then coated with glue. The glue dissolved in alcohol impregnates the winding, and after drying it forms a dense waterproof layer.

What else can the winding be impregnated with and what can you wrap the pipe with so that it does not leak: in most cases, ordinary oil-based (not nitro) paint is used. To do this, wrap the tow around the thread, apply the paint with a brush, and after tightening the thread, paint this area 2-3 more times. You can turn on the heating or water supply only after 2-3 days.

If you can’t fix the leak with your own hands, you need to turn off the heating or water supply and redo the threaded connection: completely remove the old winding, clean the threads and degrease them. New tow or FUM tape must be wrapped with preliminary impregnation with sealant or paint.

When a metal-plastic fitting leaks, it is easier to eliminate a water supply network leak: you can stop the leak by simply tightening the thread. In 90% of cases this helps;
To stop the leak, the copper circuit only needs to be soldered;
Propylene pipes on the heating circuit are repaired by replacing the cracked section with a new section of pipe - this requires a special welding machine for welding PP products - there are no other ways to weld propylene.

If you don’t know what to do if there is a leak between battery sections, then the most common repair is replacing the gasket between the radiator elements, or replacing the nipple. To do this, the system is turned off and the failed part is replaced with a new one. There are no other options other than temporary repairs - applying a patch using the method described above. This is a rather complicated process, since aluminum radiators have a very small distance from section to section.

To seal a leak on an aluminum surface between sections, you need to somehow manage to clean hard-to-reach places. To do this, you can use a cable - you need to wrap it around the leak and pull the ends one by one until all the paint is erased. A clean aluminum surface is sealed with epoxy mixed with aluminum powder or by cold welding.

Few people know, but you can coat a heating pipe with regular table salt! A small hole in a water supply line or heating pipe will immediately stop flowing if you rub it with a pinch of salt. If the hole is rather large, then salt is used together with a regular bandage - rewinding the leak area, sprinkle the bandage with salt.

If an aluminum radiator is leaking, then repair is a temporary measure for one season. To get through next winter, the radiator needs to be changed - it will definitely leak in another place.

How to fix a leak on a radiator

Not between sections, not on the threads, but simply on the body of the radiator - such cases occur mainly with cast iron or steel devices due to cavities that occur in the casting. Temporary repairs can be carried out as follows:

The easiest and fastest way to stop a leak if the hole is small is to hammer a wooden plug (plug) into it. Level it with the surface of the product, cover it with sealant or cold weld;
In addition to wood, a self-tapping screw or press washer will work well. The hardware also needs to be lubricated with sealant before screwing it into the hole.

Leaking hidden pipes

It is clear that this is the biggest nuisance that can be imagined in a newly renovated apartment. There are two options for how to seal to prevent pipes from leaking in the wall or under the floor:

If this is a heating route, then add 100 grams of dry mustard to the expansion tank. 2-3 hours are enough for small holes to heal. The next day, you need to drain the mustard water from the system and fill in with new, clean coolant. This is done to prevent the filters in the heating circuit from becoming clogged;
Mustard is a popular household method, but factory sealants that need to be poured into the coolant to prevent the pipe from leaking also work. The principle is the same - the next day the liquid is drained and replaced with clean one.

Cold welding

But repair of heating system components is required not only when replacing old radiators. Sometimes during the heating season the unexpected happens - the joints between individual sections begin to leak or a fistula (deep chip) forms. Preparing for repairs In such an unpleasant situation, the owners cannot do without cold welding. This material is an epoxy resin-based adhesive. It can help in repairing products:

of steel;
made of copper;
made of tin;
made of cast iron;
made of lead;
from nickel and other metals.

An adhesive composition produced in the form of a bar is suitable for repairing batteries . The plastic substance is placed inside, and the hardener covers it on the outside. Before use, the block must be thoroughly kneaded so that it resembles plasticine. If a small part is needed, the block is cut crosswise to maintain the proportions of the components that make up the glue. One of the popular types of such glue is Mastix, sold in small packages. One “portion” of welding is equal to 55 grams and costs about 60 rubles. Polymerization of the composition occurs within 2.5 hours. After which you can start using the heating system.

Repairs begin with preparatory actions. A film is placed under the radiator, since water and dirt cannot be avoided here. It is important to know that if you choose the method of sealing with epoxy resin or cold welding, then the radiator must be disconnected from the heating system, otherwise a coolant leak will prevent the bandage from sticking to the cast iron surface. However, this can be done when the battery is equipped with shut-off valves.

The service life of cast iron heating radiators is so long that residents take their work for granted, so if a leak or fistula appears in the wall of the device, they do not know what to do. It is especially unpleasant if the breakdown occurred in the midst of cold weather, but even in the off-season you cannot leave heating elements unattended. As a rule, preventive work carried out by heating network workers can reveal the presence of contamination or leaks in the device. In this case, there are simple ways to eliminate a leak in a cast iron heating radiator.

Construction of cast iron radiators

This type of heating device consists of sections. Models of the old type, even today, are produced in the form of “accordions”, while the new generation has a flat outer panel that provides better heating of its entire area. During operation, these devices use two types of heat transfer:

Radiation, or as professionals call it, radiation accounts for up to 25-30% of heat. It not only heats the air, but is transferred to nearby objects, providing better heating of the room.
Convection produced by the heating battery ensures constant movement of air masses around the room and accounts for about 75% of the heat transfer.

The structure of the cast iron battery, despite all the external changes, remained the same. It consists of sections equipped with:

plugs;
locking devices;
traffic jams;
shank and thermostat;
locknuts;
nipples and gaskets.

No matter how strong cast iron is, even it has its limits. As a rule, the service life of cast iron radiators is 25-30 years, and with proper care and optimal operating conditions they can operate without interruption for 50 to 100 years. The same cannot be said for the parts that hold the sections together, such as spacers. With frequent water hammer, they can “sway” or crack over time. In this case, a leak appears between the sections of the cast iron battery, which, if not eliminated in time, can cause a serious accident and a threat to human health and life. To avoid this, you need to check the condition of cast iron radiators after the end of the heating season. In this case, you can detect completely different problems in the heating system.

The most common problems and their symptoms

Everyone knows the heavy weight of radiators made of this metal. If during installation of the structure, insufficiently strong brackets were used, or there were not enough of them, over time it may sag under its own weight and tilt. Even a slight deviation of just a couple of millimeters will reduce the efficiency of the device, and if the distortion is not corrected, then after a few years corrosion will appear in the place where the coolant is missing. At first it will look like a small brown spot, which will grow with each heating season until a fistula forms in its place.
The reputation of “long-living” is characteristic of both old and new models of cast iron radiators, but provided that they are installed in the contour of an apartment building no higher than six floors. If the heating network is reliable and does not suffer from strong water hammer, then they can be installed in nine-story buildings. Otherwise, under strong water pressure, the cast iron battery may leak at the joints of the sections. In the event that a cast iron battery leaks during the heating season, you need to know in advance how to repair it. Today there are a lot of sealants that will help the device “hold out” until warm days.
The internal structure of domestic batteries is such that the cast iron from which they are made has roughness that is completely absent in imported analogues. That is why a lot of debris is deposited on the walls over time, which fills the water in the heating network. Suspensions, particles of rust and metals, all settle and make the wide channel so narrow that it is no longer able to easily pass coolant under high pressure. In this case, the structure may burst anywhere, and then you will have to urgently decide how to eliminate the leak in the cast iron battery.
Gaskets and threads of nipples are the weak “link” of heating devices

The first signs of trouble

There are a number of factors that indicate that something is wrong with the heating circuit or batteries. These include:

Feeling of coolness in the room. In this case, it is worth asking your neighbors how warm it is in their apartment. If everything is in order, then you can start looking for problems in yourself. The reason may be simple contamination of the channels, misalignment of the device, or the presence of fistulas. In the first case, it is enough to wash the batteries, in the second, fasten or change the brackets and check the correct installation with a building level, and in the third, provide assistance to the “sick” radiator.
If an incomprehensible coating appears on the battery, visible to the naked eye, then the reason for this is worn out gaskets. You will have to turn off the system, remove the batteries and install new ones, for example, from paronite.
The leak is immediately noticeable. If it is small, then you can get by with a clamp or cold welding, otherwise you will have to completely change the device.

It should be remembered that even small defects can develop into a big problem if they are not eliminated in time. Don't rely on temporary clamps and patches. Only heating network specialists can determine the reliability and tightness of the heating circuit and its elements.

Elimination of fistula

Taking into account the frequent increases in the cost of utilities, some craftsmen are cunning and, in order to save energy, connect a neutral cable to the heating circuit. The currents that begin their “journey” through the pipes through the coolant are what cause the formation of corrosion. You can identify a dishonest neighbor if there are several fistulas and they appear with a certain regularity. Calling the appropriate service to identify the intruder and repairing cast iron batteries yourself will help save the situation.
Too much acidity of water can harm even corrosion-tolerant cast iron.
The batteries have expired or deposits on the battery walls have damaged the metal. In this case, even a small fistula or crack under the influence of water pressure can cause the battery to burst and a stream of hot water to flow from it.

Any of the options requires urgent intervention. If the cast iron battery leaks only slightly, then you can do without disconnecting the circuit and dismantling it. A clamp can save the situation. If the water only drips, then a one-sided clamp will do, but if it runs in a thin string, then it is better not to risk it and use a double-sided clamp. In the event that the coolant ruptures the place where the fistula was located, the question immediately arises whether it is possible to weld a cast iron battery . As a rule, cold welding becomes an emergency solution, but even if it has restored the tightness, it is necessary to call specialists from the heating network to check the condition of the heating system.

Methods for repairing cast iron radiators

There are several methods that allow batteries to last not only until the end of the heating season, but also for a couple of years. These include:

If there is a leak at the junction of sections, it can be quickly eliminated using a bandage and epoxy glue. The material is impregnated with glue and wound around the leak. After it sets, you can paint this place to match the battery, but the main thing to remember is that such an “operation” is considered temporary, and it is better to buy and install a new section after the cold weather ends.
If a fistula or crack is detected, a clamp will be required. You can buy it at a building materials store, or you can make it yourself from rubber or tin.
Cold welding for cast iron batteries is the best way to quickly eliminate a defect.

Knowing how to weld a cast iron battery using a welding machine with an inverter circuit, you can save the device from leaks for quite a long time.

Sequence of work

Depending on how serious the breakdown is, the steps to fix it depend. So, if the leak is small, then you can do without disconnecting the battery from the circuit, and for repairs you will need:

Place a container under the breakdown site in case of a breakthrough or an oilcloth with rags to collect water.
The area of the rupture or crack must be cleaned down to the base using a cable or sandpaper. It is necessary not only to remove a layer of paint, but to expose the metal itself.
Degrease the prepared area with some solvent.
If special glue or epoxy resin is used to repair the damage, then strips of thick fabric or bandages will be required. Apply the product to them and wrap several layers around the tear site.
If cold welding is used, fabric is not needed.
A clamp is put on and screwed onto the area captured by the sealant, but it is important to ensure that its clamps are on the opposite side of the leak. For example, a crack has formed on the inside of the radiator, which means the clamps will be on the outside, and vice versa.
If the breakdown is serious and hot water is gushing out of the battery, then you need to call an emergency team, and not try to stop the leak yourself without the necessary tools.

Conclusion

You can repair cast iron batteries yourself if you have the tools and necessary materials, but only in case of minor defects. Cold welding is the easiest and fastest way to return the heating device “to operation,” but even it does not guarantee that everything will be fine in the future. To make sure that the heating circuit and all its elements will last a long time and will not pose a threat to human life, you need to either completely replace the repaired structure after the end of the cold season, or invite specialists to check its reliability.

Useful video

Classic high temperature welding

How to weld heating from an iron pipe in accordance with building codes is indicated in GOST. Both the diameter of the pipes and the length of the system matter. SNIP will indicate how to properly weld heating pipes in each specific case: private household, multi-storey building or industrial water supply line.

When using a gas welding machine, creating high-quality seams will require considerable practical experience. Electric welding can also create welded joints of impeccable quality, but in this case you will need not only experience, but also high-quality electrodes, the correct current level and “arc feeling”. High-quality electric welding of heating pipes is available only to real professionals.

Metal pipes are the most common material for heating systems

The strength of metal pipes is more than sufficient for the water supply system and for the heating circuit. It is the connection sections that have to be implemented in order not to deviate from the design documentation that are the “weak link” of the system. How to weld a heating pipe using electric welding is described in detail in outdated training materials and articles. In modern construction, the cold welding method is more often used for heating pipes.

It is important to know! Threaded connections for metal pipes are used in cases where it is necessary to create a detachable connection. The tightness of the connection in this case is guaranteed by a sealant, most often tow.

Every qualified installation engineer knows how to weld a heating pipe correctly. There are a number of rules that must be followed:

The weld should not consist of scale. This happens if you weld a pipe by electric welding using low-quality electrodes.
To weld metal with an electric welding machine, it is necessary to use a multilayer metal melt method. Primary weld scale is removed before the next welding layer.
It is important to choose the correct current level - low current does not guarantee the strength of the weld. Excessively high current during welding is also unacceptable.
If the butt welding method is used, the electrode metal or molten wire is used as the reinforcing material.
Electric welding of metal pipelines and other elements of heating and plumbing systems is prohibited near flammable objects.

Gas welding is a universal method for creating a strong connection between metals; metal parts of different sizes can be connected in any combination.

For traditional welding you need to have special equipment and welding experience

The high temperature of the burning gas stream allows you to melt the metal in the area of local heating, and cook the metal at the molecular level. Requires expensive equipment and highly qualified welders.

Construction of cast iron radiators

This type of heating device consists of sections. Models of the old type, even today, are produced in the form of “accordions”, while the new generation has a flat outer panel, which provides better heating of its entire area.

When operating, these devices use two types of heat transfer:

Radiation, or as professionals call it, radiation accounts for up to 25-30% of heat. It not only heats the air, but is transferred to nearby objects, providing better heating of the room.
Convection produced by the heating battery ensures constant movement of air masses around the room and accounts for about 75% of the heat transfer.

The structure of the cast iron battery, despite all the external changes, remained the same. It consists of sections equipped with:

plugs;
locking devices;
traffic jams;
shank and thermostat;
locknuts;
nipples and gaskets.

The same cannot be said for the parts that hold the sections together, such as spacers. With frequent water hammer, they can “sway” or crack over time. In this case, a leak appears between the sections of the cast iron battery, which, if not eliminated in time, can cause a serious accident and a threat to human health and life.

To avoid this, you need to check the condition of cast iron radiators after the end of the heating season. In this case, you can detect completely different problems in the heating system.