How To Cut An Asbestos Pipe
Asbestos pipes cost and dimensions
There are many variations for the use of asbestos pipes, this can be explained by knowing some of their features, especially their price range. You can often find applications of this type of pipes for chimney systems. An asbestos chimney pipe has some positive aspects, but there are also various nuances in this application. To understand whether it is necessary to put an asbestos pipe in the chimney and how to do it, it is better to understand this issue thoroughly.
- 1 for asbestos pipes
- 2 Features of asbestos pipes
- 2.1 Asbestos free-flow pipes
- 2.2 Asbestos pressure pipes
Features of asbestos pipes
As you can see, based on the list in the price list, asbestos pipes come in sizes from 100 to 500 millimeters in diameter, and the length is usually 3.9 meters, or 5 meters. There is an asbestos pipe with a diameter of 700 mm, but it is very rare and has not been delivered to the conveyor in production because it has too much weight.
Pipe components. This is concrete in which some of the reinforced fibers are present. The proportional ratio of these components is 85% 15%. In the manufacture, use this proportion by mixing it with water. The resulting mixture is poured onto a mesh drum. After the film is formed from the solution, it is wound on a special rolling pin, the dimensions of which correspond to the future size of the asbestos pipe.
The varieties into which asbestos pipes are divided can be:
The device of the ventilation system of the furnaces is quite demanding for those materials that are used in its arrangement. Here are some parameters that asbestos pipes cannot satisfy in their characteristics:
|Demand||Feature of asbestos pipe|
|Due to the presence of substances in the chimney that have a sufficiently high temperature level, it becomes necessary to resist the pipe material to such indicators.||An asbestos pipe cannot withstand temperatures that exceed 300 degrees. Plus, the rubber seals on it, without which the chimney design is not possible, also stretch and lose their appearance. The pipe itself is cracking.|
|In the gases that leave in the form of combustion products through the pipes, there is a large concentration of heavy substances. They then form soot and dirt on the surface they come into contact with. Therefore, there is a need that the material from which the chimney pipe is made does not accumulate such substances.||They are not able to conduct condensing substances outside, which is why they soon become clogged and covered with a large amount of soot on the walls. This is due to the large porosity of the material.|
Considering the two above criteria, which in part are decisive in the installation of a chimney, we can conclude that asbestos pipes are not very suitable for such a purpose. This is especially not worth doing if the chimney comes from a coal or wood-burning stove. However, it is possible, without any inconsistencies with the fire safety requirements, to mount such pipes in the intermediate or final part of the chimney structure. They are suitable for such chimney segments in terms of their weight and their price is also low.
The only option for an asbestos chimney can be if the heating device runs on gas. In this case, there is a need to deal with additional fire safety and make insulation. This can be done using a special insulation layer and casing. The latter consists mainly of metal that has undergone a galvanized process. The casing will become a protection if the pipe cracks or breaks, provides hermetic properties, and a layer of insulation material will prevent the formation of condensing substances.
Pros and cons
In addition to the fact that the asbestos pipe is strong enough, it also has additional positive aspects:
- Can withstand a certain threshold of negative temperatures;
- Serves for a long time;
- Has a low hydraulic resistance;
- Not susceptible to chemicals;
- Resistant to high temperatures not exceeding 300 degrees;
- Can be installed in open ground;
- Low prices;
- Has resistance to corrosive processes;
- Has a low weight;
- Characterized by convenience in connection, which occurs with a special coupling;
- A wide variety of sizes.
Despite the fact that there are a lot of advantages, including the fact that an asbestos pipe is much more profitable to purchase compared to a brick pipe, it has many disadvantages:
- There is not a sufficient level of heat capacity in order to provide powerful traction;
- Strongly absorbs condensate and various heavy substances from the exhaust gases;
- There is no possibility of application in places and installations where the temperature regime exceeds 300 degrees;
- Cannot be cleaned due to the inability to equip any access to the pipe in the form of a hatch;
- The possibility of mounting only in a vertical position;
- If the temperature regime is exceeded, then the asbestos pipe can not only crack, but also explode;
- Acts on the human body by secreted harmful substances.
The asbestos material of pipes is good for those heating systems that are not characterized by a high level of power, and the gases that come out of the chimney have already cooled down or are not able to heat the pipe to 300 degrees.
Asbestos pipe after explosion
Free-flow asbestos pipes
This type of asbestos pipe is widespread, especially in the construction industry. This type of pipe can be characterized as follows:
- Have a specific gravity that is actually less than steel pipes;
- Are resistant to corrosive processes;
- A weak degree of resistance to high temperatures;
- Cannot withstand a strong decrease in the temperature level;
- Accumulate various substances that come into contact with them;
- Not susceptible to electric currents;
- The time that needs to be spent on installing this type of pipes is very small;
- Do not require the installation of additional heat-insulating materials;
- Resistant to fire;
- Have high resistance to shock waves;
- Able to increase their strength when exposed to water.
|Properties||Unit.||Conditional passage, mm|
|Inner diameter||mm||one hundred||141||189||277||365||456|
|Crushing load, not less||kgf||460||400||320||420||500||600|
|Bending load, not less||kgf||180||400||–||–||–||–|
|The value is tested. Hydraulic pressure||MPa||0.4||0.4||0.4||0.4||0.4||0.4|
How to install an asbestos chimney
To make a chimney for a gas-powered stove from asbestos, you need to make sure that such a pipe has a diameter that is larger than the main one. For insulation, you can use mineral wool, which should preferably be arranged in several layers. The casing should be selected with a size wider than the base by 6 millimeters. Such a process can be represented by the following necessary actions:
- Insulation should be carried out using rolled mineral wool. She needs to enlighten the winding of the pipe;
- Equipment with thermal insulation will be a must. You can use foil-clad polyethylene for this purpose, which is attached to metal staples or with a wire;
- Another possible option for insulation may be the purchase of a pipe of such a diameter that can be put on the base pipe in such a way that there is no large gap between them. Usually the size of such a pipe is 5-10 centimeters larger than the base one;
- The elements need to be joined, and after that, additional intermediate places must be filled with insulation material;
- Pour cement on top. This must be done so that the insulation layer is protected from various influences of the external environment.
If, despite the indicated shortcomings in chimney systems of this type of pipes, it was decided to use them for ventilation, then you need to adhere to some recommendations during the installation process:
- Installation should be carried out in such a way that the base is a reinforced concrete slab or stone laying.
- The presence of “fluff” is obligatory in those places where the pipe crosses the overlap.
- For such a design, additional care should be taken about the integrity. For this, all formed gaps and gaps must be filled with a special material that is not flammable.
- It is best to fill such voids in the structure with expanded clay, sand or cinder concrete.
- At the place of passage through the roof of the house, it is imperative to build a special device that will protect against precipitation.
- The fixation of such a connection should be carried out with a sleeve, which can be formed using a solution of cement with sand.
An obligatory moment will be to ensure sealing at the points of connection. For this, a conventional heat-resistant sealant is suitable. Additionally, clamps are used, attaching them from above to the connection points.
It is important to understand that the use of an asbestos pipe is allowed only if it is possible to place it in the chimney structure at a sufficient distance from the heating source. Also, a good installation option would be to mount it in an existing brick chimney, where, due to the characteristics of both structures, all fire safety requirements and optimal chimney operation will be met.
How can an asbestos cement pipe be cut
Pipes made of asbestos cement have been actively used for several decades in various areas of construction, for household needs and in everyday life. Sometimes this material simply does not exist. What, for example, is the best way to build a chimney in the basement or lay ventilation in the ground? The superior properties of thick wall asbestos cement pipes are well known. They are resistant to dampness, rotting, decomposition, high mechanical stress.
In the process of performing many types of work, it is often necessary to cut a piece of pipe or shorten an existing workpiece. Just like that, very quickly, it will not work. If you apply considerable effort to some place in the pipe, the pipe will simply burst. And we want to get even cuts. Therefore, the cutting process should be approached thoroughly, competently. For example, you will not be able to do such an operation in the same way as it can be done with asbestos-cement slate. As you know, slate can be pierced with a nail in several places, and then broken along the done mowing line. It is impossible to pierce the pipe like this due to its thick walls.
There are several ways to cut asbestos-cement pipes, which will be presented below:
1. Cutting with a conventional hacksaw for metal. The complexity of this method lies in the fact that dry material is cut very poorly, and the blade quickly becomes blunt. Often, to saw off a pipe with a diameter of 10 cm, you may need a dozen hacksaw blades. The solution is to cut wet material. However, simply wetting the cut with water will not be enough. Asbestos is very slowly saturated with moisture. The pipe must be wrapped with a cloth or thick cardboard, and then moisten their surface. Keep the pipe in this state for a couple of hours, periodically wetting the cloth or cardboard.
A cutting line should be applied to the wet surface of the pipe, after which you can start cutting. The moisture-saturated pipe will be cut very easily, and the number of dull blades will be reduced.
2. Using an angle grinder. With this tool, a pipe of any diameter can be cut in a couple of minutes. However, do not use cut-off wheels for this, as they are erased from friction against the pipe at great speed. Place a diamond wheel of the appropriate diameter on the angle grinder and get to work.
When exposed to a high-speed tool on the pipe surface, a large amount of asbestos dust is released, which adversely affects the respiratory tract. To prevent this, periodically moisten the cutting area with water. It will be even better if the master is directly involved in cutting the pipe, and his assistant. Wet the cut with water.
3. Application of a special cutter. Since such tools are used relatively rarely, and their cost is significant, this cutting method has not received much popularity. Nevertheless, when there is a mass cutting of asbestos-cement pipes, the cutter is able to put the cutting process on stream.
The work is done in the following order. A line of the future cut is drawn around the circumference of the pipe. Then the cutter cuts a recess for a couple of millimeters. After that, the pipe can be easily broken by placing a hard roller under one of its sides.
Using one of these methods, you will be able to cut an asbestos-cement pipe of any diameter evenly and correctly in a short time.
How to cut an asbestos cement pipe
Asbestos-cement pipes are very popular in construction. And it cannot be otherwise, because such pipes are easy to install, resistant to aggressive media and exceed their metal counterparts in terms of service life. But very often during work it is required to cut these products, so many are worried about the question: how to cut asbestos-cement pipes?
We cut pipes with a hacksaw and a cutter
- Hacksaw. You can try sawing an asbestos-cement pipe with a hacksaw. But for this, the pipe must be wetted, since it is much easier to cut asbestos cement in its raw form, and if you just cut the pipe, then the process is long and tedious. First mark the line for the cut, then soak the rags in water and place them along the cut for two hours. Wet asbestos cement will become more elastic and cut much easier. Do not push very hard on the pipe, otherwise it may crack.
- Cutter. You will need a cutter of the type for plastic, only larger and made of better steel. Place the pipe on a flat surface and scratch the pipe under the ruler with a straight line cutter. Then deepen it to a millimeter and deeper. Place a thin strip under the scratch inside the pipe and break the cut along the mowing line. There will not be much dust.
- An ordinary ax. An ordinary ax is taken, and a pipe is cut with it along the outlined lines. You will have to strike more than one blow at the same place in order to break the pipe initially, then the work will go easier. Of course, it will not come out very smoothly, but quickly and efficiently.
- Circular. You can cut an asbestos-cement pipe using a circular. Instead of the usual disc, you need to put a disc with carbide teeth on it.
- Slate nail. If you don’t have any tools, try this simplest method. Mark the cutting line on the pipe, then take a slate nail and punch holes along the entire mowing line with it. The thicker the holes are located, the better. Place a thin, long object, such as a block of wood, under the pipe. Then gently break the pipe along the mowing line with holes.
Cutting pipes angle grinder
- Angle grinder with stone disc. This cutting requires two people. One will cut the angle grinder on the pipe, and the other will pour a small, thin stream of water from a plastic bottle onto the cutting area. In this case, all the dust in the air will not fly, but will drain as dirt to the ground.
- How to cut plastic pipes
- How to bend a steel pipe
- How to connect asbestos-cement pipes. Couplings.
- Cutting steel pipes. Steel pipe cutter
- How to connect copper pipes
- Copper pipes for air conditioners
About the nail. Can I try drilling? If so, which drill.
Homemade deflector Volpert. Grigorovich. How to make a deflector yourself and improve traction in the furnace tube.
The use of an asbestos pipe for the sleeve of old chimneys
Chimneys are made of non-pressure asbestos-cement pipes used for ventilation and water supply systems. Technical characteristics allow the use of an asbot pipe for the rehabilitation of an existing smoke exhaust system.
The sleeve helps extend the life of a brick chimney by reducing condensation. This method is especially in demand in case of partial destruction of the head of the smoke exhaust system. The pipeline is installed from top to bottom. After the renovation, the outer pipes are lined with bricks.
The connection of the boiler or furnace to an asbestos-cement pipe is carried out using a piece of stainless pipe or a special adapter. At the very outlet of the boiler outlet, the temperature easily heats up to 40-500 ° C. Therefore, it is not possible to use asbestos-cement material.
The use of an asbestos pipe lined with brick for the chimney is the optimal solution to the issue of flue gas extraction, providing stable draft and maximum service life of the system.
How to fix an asbestos-cement chimney
One of the most difficult, in the case of self-installation of a smoke exhaust system, is the accurate calculation and arrangement of outdoor chimneys from asbestos-cement pipes. Existing standards stipulate in detail what parameters the chimney must meet in order to provide sufficient draft and be able to resist wind load.
For fastening the external chimney, special clamps and stretch marks are used. During the installation of a free-standing pipe, or its overhead part, the following recommendations are followed:
- Calculate the diameter and height of the asbestos chimney. The higher the chimney, the greater the wind load it experiences. To fix the pipe on the roof, raised more than 2 meters above the ridge, roof braces are installed.
The height is calculated depending on the distance of the chimney from the ridge of the building, the diameter by volume of the combustion chamber (the recommended section is at least 120 mm).
A freestanding chimney, every half a meter is fixed to the wall with pipe clamps. In order to securely fix the pipe on the roof, a special roof base is used. Sealing against leaks is mandatory.
When installing an asbestos pipe in a brick channel, the pipe is securely fixed using special spacers. The minimum distance between the pipes of a multichannel chimney made of asbestos-cement pipes is at least 10 cm. A plate is installed on top of the structure, which closes the channels from moisture.
If you do not fix the asbestos pipe in a brick chimney, then over time the pipe at the joints will lose its tightness, which will result in the appearance of oxides and destruction of the walls.
During the passage through the roof and interfloor floor slabs, use a fastening bracket made of asbestos cement. A distance of at least 10 cm is left between combustible materials and a very hot surface, a non-combustible chimney support is installed on the wooden floor.
How and what to insulate an asbestos chimney
The chimney asbestos-cement pipe can withstand temperatures up to 300 ° C. over, the material has high thermal conductivity and instantly gives off heat to the environment. The heating of the chimney surface is practically identical to the temperature of the flue gases. Thermal insulation of the surface with a non-combustible heat-insulating material is required for several reasons:
- Insulate the asbestos chimney pipe from wood or any other combustible wall cladding.
Reduce the amount of condensate produced and avoid freezing.
Modern insulation technologies can significantly reduce the volume of condensate in the asbestos pipe and significantly increase the life of the chimney.
As practice shows, it is not enough just to wrap an asbestos pipe with heat-insulating material in order to achieve good heat-insulating characteristics, work is performed, guided by the following installation scheme:
- The choice of insulation. Basalt wool or any other non-combustible thermal insulation is suitable for work. It is better to choose a material that has a low coefficient of water absorption. If necessary, there is a possibility of insulation with mineral wool insulation.
Fixing the insulation. The insulation is wrapped around the pipe and fastened with special clamps. Alternatively, you can use knitting wire.
Protective layer. On top of the mineral insulation, insulation is carried out with foil insulation. A layer of foil protects the basalt wool from moisture ingress and serves as additional protection against fire.
The possibility of using asbestos-cement pipes as a chimney directly depends on high-quality insulation. Subject to competently performed work, the system can be mounted in a wooden house made of a bar, log or frame structure.
What is better for a chimney. Asbestos or a brick pipe?
The heating rate of an asbestos pipe is slightly higher than that of a brickwork, which clearly speaks in favor of the former. But ceramic bricks are able to withstand heating up to 600-800 ° C, so it can be used for wood stoves and other solid fuel heating equipment.
It is prohibited to use asbestos pipes for chimneys on brick stoves. With strong heating, the surface begins to crack and literally explode. After firing up the stove, at the chimney of a brick structure, the draft is much better. Cleaning of the asbestos pipe is required every few months, even a slight narrowing of the inner diameter leads to a serious deterioration in traction.
The disadvantage of a brick is:
Dependence of pipe quality on the qualifications of the builder.
The best solution in this matter is a brick chimney with an asbestos-cement pipe embedded in it. This design can be used for gas and solid fuel equipment, has good tractive power and will last much longer.
For solid fuel boilers, it is definitely better to use a brick channel, for gas equipment it is easier to install an asbot pipe.
For which chimneys are asbestos-cement pipes used?
You can make an external chimney from an asbestos-cement pipe in the following cases:
- Independent smoke exhaust system. Asbot pipes are installed as a separate smoke exhaust system. When connected to a heater, a stainless steel docking sleeve is used. To put the chimney from the outside of the house, special tees and adapters made of asbestos cement are used.
Extending the length of an existing chimney. It is required to extend the flue system with an asbestos pipe in case of insufficient draft and increased production of condensation.
Is it possible to use an asbestos-cement pipe for the chimney
The asbestos chimney was widely used during the Soviet Union for the following reasons:
- Large reserves of asbestos deposits.
In the future, during mass developments, it was necessary to install asbestos-cement pipes for the chimney in order to reduce the cost of housing. At the same time, a material was used that, to put it mildly, was not intended for smoke extraction systems.
How to cut asbestos-cement pipes with your own hands without a power tool and with its help
In the past 50 years, asbestos-cement pipes have been very popular in various works. This is due to the fact that such products are easy enough to mount, they are resistant to aggressive environments and last longer than metal counterparts. However, the problem of sawing pipes made of asbestos cement often arises. How to do it right?
Asbestos cement pipe cutting angle grinder
The most common way is to cut asbestos-cement pipes with an angle grinder. (she’s an angle grinder, an angle grinder; something like BOSCH GWS 850 CE Professional or MAKITA GA5030K).
In this case, there are 2 types of work, depending on the equipment used:
- Angle grinder with stone disc. It will take two people to cut this way. One of them should cut the pipe with an angle grinder, and the second should use a very thin stream of water to the cutting site. At the same time, dust from cutting will not scatter around the room, but flow down in the form of dirt.
- Angle grinder with diamond disc. Here you will need a respirator, construction goggles, and other protective equipment. To reduce the amount of dust that falls on a person when cutting, you need to perform this process in an open space on the leeward side so that all the dust flies to the side. If you cut the pipe in winter, then it can be laid directly on the snow so that the particles of material remain below.
And if not, alternative technologies
If you don’t have an angle grinder, you can use a cutter or hacksaw. Consider these technologies for cutting asbestos cement pipes.
- Hacksaw. It is quite possible to cut the pipe with an ordinary hacksaw, but it will take quite a lot of effort and time. Initially, the pipe should be wetted, since asbestos cement is cut much easier in the wet state, and if the pipe is sawn dry, the process will become extremely tedious and ineffective. Then it is necessary to outline the line of the cut, moisten the rags in water and lay them for several hours along the intended place of the cut. Wet asbestos cement will be much more elastic and easily cut. Do not put too much pressure on the pipe when cutting, so that it does not split.
- Cutter. To do this, you need a cutter similar to a plastic cutter, but large and made of high quality metal. Place the pipe on a flat surface and use a straight edge to scratch the cutter in a straight line. Then deepen it a millimeter and further. Under the scratch, you can put a small rail inside the pipe and break it along the cut line. This process does not generate much dust.
The above methods for cutting asbestos cement are the most popular, but if they do not suit you, you can use alternative technologies:
Classic ax. You need to take an ordinary ax and cut the pipe with it along the intended lines. It should be understood that many blows must be applied to the same place in order to initially break through the pipes, and then the process will go much faster. Of course, it will not work to cut the pipe exactly, but it will work out efficiently and quickly.
Circular. You can cut a pipe made of asbestos cement using a circular. Instead of the usual disc, you need to install a disc with carbide teeth on it.
Slate nail. If you do not have all the listed tools at hand, you can use the most primitive method. First, a cut line is outlined on the pipe, then a slate nail is taken, with which the line is pierced along the entire circumference. The more often the holes are located, the better. It is best to place a thin, oblong object under the pipe, such as a block of wood. At the end, you need to gently break the pipe along the mowing line with holes. The cut line will not be perfectly flat, in any case, it all depends on the number of holes made and the accuracy of the break.