Today, there are many chimneys offered on the building materials market. The issue of choosing stove equipment must be approached very responsibly, because the fire safety of the entire house depends on it. This main criterion is best met by a sandwich pipe.
She is very popular, and for good reason. The sandwich chimney has a lightweight and compact design, it is practical and functional. And most importantly, you can easily install it yourself.
Main characteristics of sandwich chimneys
Sandwich chimneys are a structure that has three layers. This design consists of an outer and inner pipe different diameters, and a layer of thermal insulation is laid between them. That's why chimneys got their name. The inner pipe must be made of of stainless steel, and the outer part can be made of galvanized steel or other material. Sandwich pipes for chimneys differ in diameter and thickness of thermal insulation, depending on the temperature conditions at which they will be used. Such furnace devices have many advantages compared to other types:
- There is no condensation;
- Easy installation;
- The highest degree of fire safety;
- Compactness;
- Resistance to aggressive environments.
The only drawback of such a device is its expensive price. Today, sandwich chimneys are the most the best option, since they can be installed in houses built from any material. They have a high degree of reliability and safety.
Sandwich pipes for chimneys are sold in parts, the length of each segment does not exceed one meter.
Types and sizes of connecting elements
Depending on where the stove heating will be used, the diameter of the pipe is determined. The diameter of the inner pipe is selected, since it bears the main temperature load. The diameter of the sandwich pipe is determined based on the power of the heating device: the more powerful it is, the larger the cross-section is required. The dimensions of furnace equipment are regulated by SNiP. Basically, the diameter is indicated in technical passport device: for example, 120\180; 150\210 or 200\260 mm. The first number is the internal section, and the second is the external. A stainless steel pipe can be used for gas and solid fuel boilers, stoves, fireplaces, saunas, and as a segment when installing vertical parts stove heating. Connecting parts made of stainless steel of the appropriate diameter are selected for this pipe:
- Chimney-convector 120, 150, 200 mm - designed to remove combustion products;
- Elbow 120, 150, 200 mm - consists of several parts welded at an angle, thanks to which you can change the direction of the chimney;
- Tee 120, 150, 200 mm - used for removal of gases and condensate;
- Revision 120, 150, 200 mm - designed to clean the chimney from soot;
- Adapter 120, 150, 200 mm - used to connect elements;
- Kagla 120, 150, 200 mm - used to regulate traction;
- Thermal weather vane 120, 150, 200 mm - designed for protection from precipitation and blowing wind;
- Thermo cone 120, 150, 200 mm - serves to protect against precipitation;
- Rosette 120, 150, 200 mm - is an auxiliary element and is intended for decoration;
- Mushroom 120, 150, 200 mm - consists of galvanized steel and is intended for the top of the chimney.
The thicker the stainless steel, the longer term stove heating services.
Sandwich structures made of stainless steel ensure high-quality removal of combustion products, and thanks to galvanized steel, the chimney can be supplemented with different decorative elements.
Do-it-yourself installation of furnace equipment
The sandwich chimney design initially has a high degree of fire safety, so it is not difficult to install. And by adhering to some rules, you can install it yourself. The main recommendations are:
- When a pipe passes through the most fire-hazardous area, an additional layer of thermal insulation is required;
- It is prohibited to install a sandwich pipe above the furnace device.
The most common thermal insulation layer is basalt fiber, as it has good resistance to various influences. chemical substances And high temperatures. According to SNiP requirements, the dimensions of basalt insulation should be no more than 25-60 mm. Do-it-yourself installation of the structure can be carried out according to two principles:
- By the smoke;
- By condensate.
Chimneys are collected according to smoke in order to prevent carbon monoxide from entering the house by securing tees. The condensate is collected so that the condensate resulting from the temperature difference can flow down the pipe. With this installation, tees are not required. It will be correct if the inner part of the pipe is installed for condensate, and the outer part for smoke. Whatever method is chosen, the most important thing is that high-quality sealing of the joints is necessary. The chimney is connected in the following ways:
- Flanged;
- Bayonet;
- Bridge of cold.
You need to correctly install the structure with your own hands from the stove to the roof, connecting all parts step by step with clamps. To work you will need the following tools:
- Roulette;
- Level;
- Jigsaw;
- Bulgarian.
The first part of the structure is installed from stainless steel without a layer of insulation, since the insulation will burn due to exposure to high temperatures. In order for the structure to be reliable, it is better to use a special high-temperature sealant to connect the joints. At high degree tightness, the thrust is much higher.
Some difficulty when installing stove heating with your own hands can be a passage through the ceilings. To do this, it is necessary to cut an opening and lay another layer of thermal insulation in the places where the ceiling comes into contact with special pipes. Next, the pipe is passed through the opening.
Having built your house, the question arises of how to insulate it, how to make it optimally suitable for living.
The main type of heating in modern houses use autonomous heating units that run on wood, natural or liquefied gas.
Combustion products must be removed through the chimney system. On modern market There are many companies offering installation and production of chimneys.
To choose the right chimney, you need to understand their design and application.
There are two types of chimneys
A double-circuit (sandwich chimney) consisting of two pipes, between which insulation is laid, which, as a rule, is not only a good insulator from the cold, but also a good fire-retardant material.
The outer tube is made of 409.439 stainless steel.
1mm or 0.5mm thick and available in matte or mirror finish.
The inner pipe can be galvanized or stainless.
The choice of steel and its thickness affects the durability of the structure and, accordingly, its cost. This does not affect the parameters and quality of combustion product removal. A single-circuit chimney is an ordinary pipe, which can be made of stainless or galvanized steel.
The cost of a single-wall chimney is several times less than a double-wall chimney! But why then is it recommended to install a sandwich chimney, despite the fact that it costs more?
The design of the double-circuit chimney does not allow moisture to accumulate and prevents the formation of condensation. It all depends on the difference in temperature of the exhaust combustion gases and the temperature of the outside air.
If there is a large temperature difference, condensation forms on a single-circuit chimney, since warm air the exhaust gases come into contact with cold air, the formation of condensation reduces its service life.
On inside pipes, soot from combustion products is formed, interacting with water droplets leads to a faster corrosion process and failure of the chimney. The production method of a double-circuit chimney prevents the formation of condensation.
Installing an insulated chimney will save you from this problem and increase the service life of the system. The chimney kit includes: tees, plugs, bends, condensate drains and much more.
Installation begins from the heating unit, with the pipe exiting through the wall of the house or through the ceiling, followed by passage through the roof. In this case, pass-through devices are used for ease of installation.
Particular attention must be paid to fire safety. To ensure good traction, it is necessary to install the pipe to a certain height, at a certain distance from the ridge of the house, in order to avoid air flow, which are formed by the wind.
If the pipe outlet is positioned incorrectly, backflow can occur. This is a phenomenon in which air from the street flows back into the pipe.
Exhaust gases will not be removed, but will accumulate in the house, which can lead to severe consequences... To select all the necessary chimney elements, you need to contact specialists.
If all components are available, the chimney can be installed by a team of installers within one working day.
Buy a sandwich chimney http://tp-service.com.ua/catalog/sendvich-dymohod-uteplennyj from proven and well-established companies in the market.
The term "sandwich" appeared in 1762. This is what closed sandwiches were called in honor of Count John Sandwich. Nowadays, this term is used in structural materials to designate multilayer composite structures. The advantages of a composite made of several layers are well known, these are increased structural strength, the ability to use a soft or fragile material, such as insulation, for example, as a core. Applications in construction are varied. It is worth considering another application of a multilayer device - sandwich pipes for chimneys. Read more in our material.
Read in the article
Multilayer pipes for furnaces: why are they needed?
Chimney - necessary element heating system operating by burning fuel, it ensures the removal of combustion waste: carbon monoxide and smoke. The working conditions can hardly be called easy. Due to the fact that the height of the chimney reaches large sizes, then the material must withstand high vertical loads; work exposed to open flames and high temperatures also imposes its own requirements. In addition, the material must withstand constant temperature fluctuations outside the pipe surface and inside it.
The surface inside the chimney must be smooth and allow the chimney to be cleaned, since during combustion, in addition to gaseous products, soot and soot are also formed, which settle on the inner surface of the chimney, making it difficult to remove the chimney and threatening the risk of fire and subsequent fire.
Sandwich pipes for chimney installations meet all the requirements for chimney pipes. These pipes consist of an internal channel made of stainless, heat-resistant steel, coated with a layer mineral insulation. Installed on top of the insulation protective shell, stainless or galvanized steel or sheet metal covered with a powder protective coating.
The connecting seam of the outer shell can be welded automatically or sealed with a folded seam.
For the manufacture of the inner pipe, the following grades of stainless alloy steel are used:
- AISI430, a relatively inexpensive stainless steel, can withstand temperature fluctuations. Fastening is most often done using a seam seam, since this metal does not weld well;
- AISI439, steel alloyed with titanium, which made it possible to achieve increased heat resistance, has good anti-corrosion characteristics;
- AISI316, nickel-molybdenum alloy steel with increased heat resistance, recommended for liquid fuel boilers and gas heaters;
- AISI304, a close inexpensive analogue of 416;
- AISI321, the most popular heat-resistant alloy steel, has excellent anti-corrosion and heat-resistant characteristics;
- AISI106S, a relatively rare heat-resistant alloy, extremely high performance heat-resistant, practically resistant to corrosion. Used for expensive products operating under high thermal loads.
sandwich pipe
It should be noted that for outer shell Both galvanized carbon steels and inexpensive alloy steels are used; the second option is more resistant to external factors, but at the same time the cost of products using it is quite high.
Mineral, non-flammable types are usually used as insulation for sandwich pipes. mineral wool or basalt.
To connect pipe modules to each other, one edge of the pipe or fitting has a socket; on the other side there is a corrugated, narrowed area, which serves for wedging in the socket and creating a reliable connection, impenetrable to gas and smoke.
Sandwich pipes for chimneys - luxury or panacea?
Traditional materials for chimneys were brickwork, metal, ceramic and modern sandwich pipe for . The disadvantages of such chimneys are known, but it is worth comparing the advantages and disadvantages of various chimney systems:
- Brick chimney. The reliability and functionality of such a design depends entirely on its weight. Therefore, a reinforced tank is needed. A brick chimney is heavy, which affects its base, and also requires large investments in construction and maintenance. Construction of a brick pipe is a labor-intensive and complex process. Bricks crumble and deform from the effects of temperature changes; over time, the brickwork requires repair. Maintenance of such a pipe is also complicated, due to unevenness on the inner surface, soot and soot begin to accumulate there, which must be periodically cleaned;
- Steel pipe as a stove. Again, due to the high temperature loads on the wall, its sufficient thickness is required, and the thicker the wall, the heavier the product itself. In addition, steel, under the influence of temperature, can burn out, and condensation on its surface can lead to corrosion of the metal, and subsequent failure of the pipe. Installation of such a chimney is also complicated, requiring either the use of a solid product or the use of special connection methods, such as. The advantage of such a chimney exhaust device is its price;
- Ceramic pipes, clay mixture products, subjected to heat treatment, has high heat-resistant characteristics, and is mounted quite well. Durable. The disadvantage is its high weight and, compared to metal, low strength characteristics.
- Chimney pipe sandwich. Lightweight design consisting of separate, easily connected modules. Installation does not require special equipment or experience. The structure can be displayed in any direction, including in a horizontal or inclined position. It should be noted that the device is simple: fasteners and individual modules. The sandwich stove pipe consists of three layers: an internal channel made of heat-resistant steel, a layer and an external, protective pipe. The chimney itself is quite light, so fixing it will not cause any special problems. The inner surface of the pipe is smooth, made of heat-resistant alloy steel, which greatly facilitates its cleaning. The insulation will protect the steel from condensation and corrosion. The outer, protective shell serves to protect against the influence of the external environment.
It is clear that stove pipes and chimneys of sandwich construction are a little more expensive than conventional steel ones, but over the course of their service life (which is 25 years), all costs for the composite will be fully recouped, since, unlike steel, these chimneys do not burn out or rust.
Reviews about sandwich pipes for chimneys are also positive. Users appreciated the ease of installation of the structure, its durability and appearance.
Related article:
From this review you will learn: varieties, average prices and features of design choice; rules, work requirements and features of chimney installation, recommendations of specialists.
Sandwich pipe module dimensions
A sandwich pipe for chimneys with a diameter of 115-120 mm is considered the main one for small country house or dachas. in such houses it rarely exceeds 3.5 kW. For higher power systems (from 5 kW), pipes with a diameter of 180 mm are used, for heating systems with a power of over 7 kW, pipes with a diameter of 220 mm or more are used. The range of sandwich pipe sizes for chimneys is wide and you can quickly and easily select the required diameter in accordance with SNiP standards.
When calculating the diameter of the sandwich, do not forget about other elements of the chimney: fasteners, clamps, start sandwich, damper module, transitions through ceilings or walls.
But not only the diameter of the sandwich pipe for the chimney is important, the height of the module is no less important. It is necessary to calculate the length of the chimney, taking into account the pipe exit above the ridge of the house to a height of up to 1.5 meters, the height of the pipe exit depends on a number of factors and it must be selected individually, but on average the length of the exit is 0.5-1 meter above the ridge of the roof.
Sandwich pipe modules are supplied in several versions, the most common being 0.25, 0.5 and 1 meter high.
Any room with a solid, liquid or gaseous fuel stove requires a chimney that removes combustion products to the outside. Sandwich chimneys are currently very popular. They are easy to install and also easy to dismantle. Sandwich pipes are an improved type of metal pipes: these are two pipes of different diameters, inserted into one another, and the gap is filled with heat-insulating material.
Let's look at their positive and negative sides. Let's start with the shortcomings. There are not many of them, but they require attention:
The advantages of such chimneys are much greater and they outweigh the disadvantages. Let’s determine what makes a sandwich chimney so attractive:
How to choose
- When choosing sandwich pipes, you need to pay attention to the following:
- The quality of the steel from which the product is made. It affects such indicators as heat resistance and service life.
- Thermal insulation material and its filling density: It must withstand heating temperatures of at least 700 °C.
Quality of welds. Give preference to products with laser welding - it ensures the necessary tightness of the pipes. If the seam is “rolled”, these are pipes for chimneys.
The inner layer of a sandwich pipe is most often made of stainless steel, since it “accepts” the highest temperatures and is affected by condensation. If the inner pipe is made of galvanized metal, it can be used to remove combustion products from gas boilers. For solid fuels, it is even more undesirable to use them. In principle, it is possible, but very soon you will have to change the entire chimney. The outer contour can be from- galvanized steel, stainless steel, copper, polyester, brass, etc. And again, for stoves that do not use solid fuel, it is better to use stainless steel; galvanization is also acceptable. Other materials are used for lower temperature chimneys or for ventilation systems.
The best grade of stainless steel for making internal pipes is 316 Ti, 321 and 310S are universal grades of stainless steel. Sandwiches made from them can withstand temperatures of 850°C, and the latter - more than 1000°C, have high heat resistance, ductility and durability. Such elements are desirable in the chimneys of sauna stoves and
For chimney from sauna stove the preferable option is that both pipes are made of stainless steel, but the outer casing does not have to be made of stainless steel. The main thing is the inner pipe. The wall thickness in stainless steel sandwiches can be from 0.5 to 1.0 mm. For a sauna stove, they are suitable either with a thickness of 1 mm (this is made of stainless steel, which is magnetic) or 0.8 mm (this is if it is not magnetic). We don’t take 0.5mm walls into the bathhouse - these are sandwiches for gas boilers. They burn out very quickly in baths.
When talking about the diameter of the chimney, we mean the cross-section of the internal pipe. They are also different, but the most common in the construction of a bathhouse are pipes 115x200, 120x200, 140x200, 150x220 (diameter of the internal and external pipes in mm). The standard module length is 0.5 m - 1 m. Inner size choose according to the diameter of the smoke channel outlet on the stove, and the outer one depends on the thickness of the thermal insulation.
The thickness of the insulation layer ranges from 25 to 60 mm. It is clear that the more the better. For sauna stoves, basalt wool should be used as thermal insulation. Precisely basalt. Glass wool (this is also mineral wool) cannot be used: it can withstand up to 350 o C. At higher temperatures it sinteres and loses its properties. In chimneys from sauna stoves, temperatures are often higher and 500-600 o C (depending on the type of firebox and combustion intensity) is not uncommon.
To determine the length of the chimney, you need to consider the following rules:
- the smoke exhaust duct must be 5 meters or more long, if less, it is necessary to connect an electric smoke exhauster;
- above flat roof the pipe must rise at least 50 cm;
- if the pipe is located less than 1.5 meters from the ridge, its height should be taken 500 mm above the ridge;
- when placing the chimney at a distance of 1.5–3 m from the ridge, it can be installed at a level with the upper boundary of the roof, and if more than 3 meters, below its level with a slope of no more than 10 degrees;
- if buildings above the bathhouse are located nearby or adjacent, it is necessary to bring the pipe above these extensions.
Following these rules will help you accurately determine the length of the chimney. Now let's take a closer look at the features of its installation.
How to install a sandwich chimney in a bathhouse
The chimney can be connected both to the heating unit itself and to the heat exchanger (tank), if it passes through chimney. The chimney configuration can be different: in a straight line through. Schemes for chimneys for different locations of chimneys on the stove are shown in the figures.
In the bathhouse, in order to make maximum use of combustion energy, a regular metal tube is placed from the stove, and then sandwich pipe modules are installed on top. In this case, hard thermal radiation comes from this pipe: the temperature differs little from the temperature in the firebox. To soften the radiation, but also not to lose heat, a mesh is made on the pipe, which is filled with stones. In this case, the thermal radiation will be much softer, and the heated stones will dry the steam room after the stove has been extinguished.
Self-assembly
Let’s say right away that the chimney in bathhouses is assembled “according to the smoke.” The temperature in the chimney when burning wood is very high and the formation of condensation is very small. More often, this problem occurs when the oven is “cold” and has not yet warmed up. In any case, it is better to solve problems with condensation than to get burned... Therefore, the solution is clear: we collect “by smoke”.
About what this means in practice: sandwich modules have slightly larger diameter, than with the other (for docking). When assembling the chimney “according to the smoke,” you place the module on top: the narrower part into the wider one.
Assembling pipes “By smoke”
Be sure to seal the junction of the modules. If this is not done, air (oxygen) enters the cracks, which can cause a flame to appear in the pipe. Either unburnt pyrolysis gases or soot can burn. Oddly enough, there is something to burn there and the combustion temperature of soot is about 1300 o C. This is how chimneys burn out and fires happen. Therefore, we coat the joints. It is useless to indicate brands - there are a lot of them and each region has its own. The main difference is the black color of the packaging and the sealant itself (not red). This is how sealants are packaged that can withstand temperatures above 1000 o C.
The main points of selection and installation have been clarified. Let's start assembling. You will need:
- sandwich modules in required quantity and configurations;
- single-wall metal pipe / or sandwich mesh;
- heat-insulating materials (asbestos cardboard, asbestos thread, basalt wool, steel sheet, wire, metal clamps);
- silicone sealant and tools.
Procedure for assembling the structure
Design the chimney so that the length of the horizontal parts of the chimney does not exceed 1 meter. At least every 1.5 meters, pipes must be secured to the wall using brackets. Another important point: There should be no connections in passages through walls, ceilings or roofs. This is absolutely impossible.
Preparatory work
We prepare the holes in the ceiling and roof necessary for installing the chimney. Remove the labels from the sandwiches and protective film, degrease.
After this, we install a damper (valve inserts), if there are none in the sauna stove. If the ceiling in the bathhouse is low, then the damper can be attached directly to the heating unit (heat exchanger, tank) without using single-wall pipes.
Please note that you cannot place the sandwich first from the oven. It is best to install a single-wall stainless steel pipe, a water tank, and a mesh for stones adjacent to the stove. Sandwich modules are already attached to them.
This design will allow you to obtain additional heat from the flue gases, dissipating the main heat at the first stage and preventing the elements located above from overheating.
Connecting sandwich structural elements
We insert the pipe modules like this: the inner part - into the lower pipe, the outer part - onto the outer part of the lower element, that is, the upper element is inserted onto the lower one, and not vice versa - this is important (assembly according to smoke). For convenience, we simply lower the internal pipes down and connect each of them in turn (internal and external). We treat the pipe joints with silicone or silicate high-temperature sealant (they have black packaging and must withstand temperatures of 1000 o C and above).
If you plan to make the structure collapsible, you need to apply sealant to the joints. If you fill the entire connection, the pipe will become a monolith and it will be impossible to disassemble it. Please note that you can strengthen the connections with galvanized clamps, which need to be wrapped around the pipe and secured with nuts or wire.
Sandwich passage through the ceiling and roof
– one of the most fire-hazardous places in the bathhouse. Therefore, it is important to take into account every little detail. Firstly, minimum distance from the chimney body to the edges of the ceiling should be 130 mm. From the flame inside the pipe to wooden walls- not less than 380 mm. When attaching thermal insulation to the ceiling passage, do not use a galvanized sheet of iron - when heated, it emits dangerous decomposition products.
When passing through bath ceiling we use a special one. With its help, a protective cushion is created between the insulation and the casing, which makes it possible to reduce the cutting of the ceiling without losing its insulating properties. A non-flammable heat-insulating material is placed under the base of the polyurethane foam and around the chimney, which can withstand temperatures of 800-1000 o C.
You can make polyurethane foam yourself. To do this, mineral wool or other material is placed in the passage between the pipe and the ceiling. non-flammable material(asbestos, fiberglass), and to strengthen it, a metal sheet is attached to the bottom.
When passing a chimney sandwich through a hole in the roof, you need to fix it in any way. Can be used metallic profile and self-tapping screws, a galvanized sheet of iron with a similar hole, which is then attached to the roof from above. Additionally, a special silicone seal-lining is used, which will prevent water from entering the attic.
Thanks to its simple design and light weight, installation of a chimney made from sandwich pipes for a bathhouse is very simple and can be done by any craftsman.
Sandwich chimneys (double-circuit) are optimal solution in cases where it is necessary to place the chimney openly, inside or outside the house. They represent two metal pipes of different diameters, nested one inside the other. In between them there is a layer of non-flammable insulation, which prevents the outer surface of the chimney from heating up.
In chimneys, depending on the type of fuel of the heat-generating device, chemically active substances precipitate and accumulate: salt and sulfuric acid, sulfur. Ordinary ferrous metal oxidizes and burns out very quickly. Sandwich pipes are made from materials that are acid-resistant and non-corrosive:
High alloy stainless steel
High alloy stainless steel - perfect material for the production of fire-resistant and chemical-resistant chimneys. High-quality stainless steel is designed for long-term exposure to temperatures of 850 °C, and short-term exposure to temperatures of up to 1200 °C. For the manufacture of double-circuit pipes, steel with a thickness of 0.5-1 mm is used. For the internal contour, take a sheet with a thickness of at least 0.7 mm. The outer shell can be made of thinner steel.
Sandwich chimneys can be installed both outside and inside buildings
There are different grades of high-alloy steel, not all of them are equally suitable for making sandwich pipes. The best properties has steel grade AISI 321. Due to the high molybdenum content, it has high heat resistance and maximum acid resistance. The brands AISI 304 and AISI 316 have relatively good properties. Popular brand AISI 409 is less heat and acid resistant. AISI 430 resists the effects of acids the worst. The maximum possible short-term heating for AISI 430 is 900 ° C, which is three hundred degrees less than that of the AISI 321 brand.
Example of a sandwich chimney design
Unfortunately, AISI 430 metal products today account for lion's share market sandwich chimneys. Most of the Chinese-made pipes and some domestic ones are made from this inexpensive brand. A chimney made of high-quality metal AISI 321 with a thickness of 0.8-1 mm can last a hundred years or more. At the same time, a cheap pipe, and even made from thin metal, under conditions of exposure to acids and high temperatures, it can burn out after 10-15 years.
When choosing sandwich chimney pipes, you need to save wisely. It is impossible to determine the grade of steel by eye. If the pipes are not marked, you can check the metal with a magnet. Low-quality steel is magnetic; a magnet is not attracted to metal with a high content of alloying additives. High demands are placed only on the inner pipe of a double-circuit chimney.
Sandwich pipe elements made of polished stainless steel
Stainless steel sheet can be matte or polished. Polished metal is like a mirror and looks very attractive. Over time, the shine does not fade. Such pipes, as a rule, are left open in the interior: they serve as its decoration. However, the polishing can be easily scratched if handled carelessly; installation of chimney elements should be done carefully, and the protective film should not be removed until completion. finishing works in the house.
Enameled ferrous metal pipes
A slightly less heat-resistant option is enameled ferrous metal pipes. The enamel is designed for operation at temperatures up to 500 °C and short-term heating up to 750 °C, and is not afraid of acids. This is sufficient for heating boilers and heating columns. Enameled pipes are also suitable for stoves and fireplaces in normal operation.
Enameled pipes have an attractive appearance. The main color is black, but manufacturers also offer color options
Combined sandwich pipes
In order to save money, combined sandwich pipes are also produced. The inner pipe is made of more expensive stainless steel, the outer pipe is made of enameled or galvanized metal.
As internal insulation basalt or ceramic wool is used. The first does not change its properties when heated to 600 °C, the second - 1000 °C.
Properties of chimney sandwich pipes
Rotating section. The sandwich structure is clearly visible
Characteristic design features
Typically, sandwich pipes have round section. Inner diameters may vary. For heating boilers with a power of up to 40 kW - this is 130-200 mm, for stoves and fireplaces - 200-280 mm. The thickness of the insulation varies from 30 to 80 mm, in some cases even more. The thicker it is, the lower the temperature outer pipe. To install a chimney outside the building, a well-insulated pipe should be used.
The range of produced sandwich pipe elements allows you to solve any installation problems. These are straight sections of different diameters (lengths 0.25, 0.5 and 1 m), turns, starting and ending elements, caps, fastening parts, passages through the roof and ceiling.
Modern systems steel chimneys include all possible elements. If they are not enough, you can make products according to custom sizes
How to get good traction
Prerequisite for the successful operation of a stove, boiler, fireplace - the presence of constant stable draft. To ensure this, a number of conditions must be met:
- The height of the chimney must be 5 meters or more.
- It is required to maintain the regulated height of the pipe head above the roof ridge; its value depends on the distance between the pipe axis and the ridge, but not less than 0.5 m above the roof surface.
- It is desirable that the chimney be straight and vertical. Sloping areas of 45 °C are allowed. The heating device can be connected in an almost horizontal (2° slope) section up to one meter long. The horizontal section can be increased to 2 meters when the chimney height is increased beyond the minimum 5 meters. The total length of such sections in horizontal projection should not exceed: for stoves and fireplaces - 2 meters; boilers - 3 meters. It's better to minimize them. There should be no more than three turns in total.
Chimneys cannot be installed below these marks. Higher is possible
Installation principles of sandwich systems
The installation of a sandwich chimney must be carried out in strict accordance with the instructions, in compliance with fire safety measures and safety precautions. You need to wear gloves when working: the metal is quite sharp, and if you handle the pipes carelessly, you can cut yourself.
As a rule, an adapter is installed on the pipe of a heating unit (stove, fireplace, boiler) or its damper, which is an uninsulated single steel pipe. It can be very short or extended if it is necessary to increase heat transfer and reduce heating of the chimney.
If necessary, the high adapter is protected with a casing or screen to avoid burns from touching. This element is installed “by smoke”, that is, it is placed outside on the heater pipe, the smoke does not penetrate outside when exiting. The joint is sealed with a heat-resistant sealant designed for temperatures of 1000 °C.
The lower section of the chimney is made of a single pipe, which increases the heat transfer of the stove. The distance from a single pipe to wooden walls should be at least half a meter.
The next element is the starting element. This is a double-circuit pipe, hermetically sealed at the lower end. Bottom part The inner pipe of the starting element is inserted “along the smoke”. The top one is designed in such a way that subsequent pipes are installed “on condensate” in order to prevent condensate from getting into the insulation. The starting element is also sealed.
The first element (adapter) and the starting pipe are mounted “along the smoke” (left), all the rest are mounted “along the condensate” (right)
Next, the pipes are installed from the bottom up. All elements up to the very top are installed “by condensation”. The inner pipe of the upper element is inserted inside the lower one, the condensate drains without penetrating into the sandwich structure. It is not necessary to use sealant, but it is advisable. Every two meters in height, the pipe should be grabbed with a clamp and secured to the wall or ceiling; it is better to place them at the junction of the pipes.
Passages through ceilings, roofs and walls (if the pipe is placed externally) are carried out using flanges and sealing linings. Inside the passage, combustible structures are separated from the chimney by a layer of basalt wool 150 mm thick.
The gap between the pipe and wooden structures fill in basalt wool. On top you can put an apron made of the same stainless steel or other fireproof material
The design is completed by a cap on the roof. According to the standards, it should be open and have the shape of a cone. In practice, to prevent precipitation from entering the chimney, an umbrella or deflector is installed that does not prevent smoke from escaping.
Which chimney should you choose? The answer depends on what kind of heating device you plan to connect. For example, combustion products of liquid fuel boilers contain greatest number aggressive components, but the temperature of the exhaust gases is relatively low. Pipes coated with enamel or a sandwich with inner pipe made of acid-resistant high-alloy steel.
General scheme chimney. On the left - in the house, on the right - when taken outside. When located outdoors, cleaning the bottom of the pipe is mandatory; indoors, it is advisable.
For constantly used stoves and fireplaces, it is worth using a stainless steel chimney with maximum heat resistance. And the fireplace in the country, which is not the main one heating device and is used only in the off-season and on holidays, it can also be connected to a budget chimney made of relatively inexpensive stainless steel.
Is it possible to install a sandwich pipe yourself? Can. However, it should be noted that installation errors are unacceptable. If there is no complete confidence that it will be possible to guarantee strong fastening, tightness and fire safety chimney, it is still worth entrusting this work to experienced, proven craftsmen.