Pipes

Corrugated stainless steel. Specifications. How to choose and mount corrugated pipes

December 21, 2019

Stainless corrugated heating pipes are relatively new products with wide prospects. They are adapted for operation in the conditions of the raised temperatures and the considerable range of working pressure. Installation is carried out without the use of special equipment. Products are bent at almost any angle, while the duct does not narrow.

Corrugated metal pipes are suitable for the installation of hot water and heating systems

How to make a corrugated pipe for heating

The technology of production of corrugated pipes from stainless steel for heating is developed in Japan. Stainless steel corrugated pipe for heating is born, having passed several stages of technological process:

  1. High quality steel tape is fed to the forming line. Corrugated pipes are characterized by low carbon content and the presence of chromium in the alloy (18 percent) and nickel (8 percent). Having passed the system of bending machines, the steel strip is transformed into a cylindrical workpiece.
  2. By means of special clips during rolling from a smooth-walled cylindrical pipe corrugated pipe stainless steel turns out.
  3. Then the pipe is fed into a closed vessel, filled with a special gas mixture. It is this mixture that achieves high quality weld and the ability of the product to successfully resist corrosion. Another circumstance, which improves the quality of the product, becomes execution of welding of joints by the automatic equipment. Elimination of the human factor avoids accidental errors in the production of works.
  4. The plasticity of corrugated stainless steel for heating is provided during the annealing. Conducting heating to high temperature (950-1150 ° C) followed by cooling to 200-400? C allows you to achieve more bends during operation / unbending. External differences between the product, who have undergone annealing, and do not anneal, does not exist, but the difference in quality and, in accordance, in value, is quite significant.
  5. The resulting product is cut into dimensional pieces up to fifty meters long and rolled into bays.

The flexibility of the corrugated pipe is due ??method of its processing during production

Check of tightness of a corrugated pipe stainless steel passes immersion of a bay in water with simultaneous supply of air under high pressure.

Technical characteristics of corrugated stainless steel pipe

Corrugated stainless steel heating pipes are available in only a few standard sizes. Standard values ​​of the inner diameter of such pipes: 15, 20, 25 and 32 mm. Production of products of larger diameter and non-standard sizes is not difficult, but is carried out only by agreement between the customer and the manufacturer.

Operating temperature range is from -50? WITH (moreover, the flexibility of the corrugations is maintained even when -40 ° C) to +800? WITH. Naturally, that at such temperature increases nobody uses a corrugated pipe, since the upper values ​​of the operating temperature are limited by the plastic elements of the fitting +110? WITH, otherwise they will melt. However, a short-term temperature jump is allowed +150? WITH.

Importantly! You can bend the corrugation almost as you wish, but regulations set a limit on the amount of bending, equal to three times the diameter.

Stainless steel corrugation is characterized by simply incredible impact strength, that allows to transfer sudden jumps of pressure of working environment without the slightest damages. The claimed parameters indicate the maximum pressure in 50 atm, but the product withstands a tensile impact of even four times the power. Operating pressure value - 15 atm. The corrugation is characterized by one hundred percent oxygen impermeability and a low value of the coefficient of roughness - 0,008.

If you follow the rules of operation, the manufacturers guarantee, at least, twenty years of trouble-free operation of its products. At the moment in the Russian market of corrugated stainless steel in heating systems are not operated for so long. Therefore, it is not yet possible to verify the claims of foreign manufacturers on domestic experience.

Stainless corrugation in heating systems can last for decades

Advantages of using corrugated stainless steel in heating systems

For a relatively short time of operation of corrugated stainless steel has managed to demonstrate a considerable list of advantages over other materials, used in the installation of heating systems. What is the invention of Japanese engineers:

  • flexibility. If you need to bend at a certain angle of the corrugation, then it is done without the use of tools and extra effort, by hand. Due to the high flexibility of the material, eliminates the need for multiple connections, which significantly affects the efficiency of the system and the cost of installation;
  • strength;
  • high heat transfer coefficient. Due to this property, stainless steel corrugation can be successfully used instead of a heating radiator;
  • anticorrosive and chemical inertness. No influence of the working environment, no effect of atmospheric phenomena will affect the operation of corrugated stainless steel pipes. The risk of electrochemical corrosion is eliminated by carrying out a simple grounding procedure and / or arrangement protects the shell;
  • the possibility of closed stacking. Such a pipe is allowed to be laid in the walls, and to the floor;
  • resistance to sudden changes in temperature and pressure. Corrugated pipe is not afraid of water hammer, nor the worst threat in the form of thawing, which disables the heating system, constructed of similar products from polymeric and metallic materials. When the coolant freezes, its expansion in volume will be easily compensated by corrugation, it will not be deformed and will not fail. And it will be possible to warm up the frozen site even by means of a blowtorch;
  • smoothness of the inner surface. This helps to increase the capacity of the pipe. And also prevents clogging, siltation, etc.. P .;
  • resistance to fungus and mold. And rodents do not pose the slightest threat to stainless steel;
  • manufacturability of installation. Two pipe wrenches are required to install special fittings. Without all other special equipment, in principle, you can do without;
  • light weight, which affects the best in transportation and assembly;
  • low noise;
  • long length of measuring segments. This makes it possible to assemble fairly large structures, without making additional connections;
  • virtually unlimited service life;
  • environmental friendliness.

Stainless corrugated pipe is supplied in long lengths in bays

Possessing such attractive properties, stainless steel corrugated pipes are quite capable of competing with polymer and metal in the installation of heating systems. At least, a certain niche in the market, due to its indisputable advantages, they have already won back.

What are the disadvantages of corrugated pipes can not be forgotten

Products, devoid of flaws, does not exist on the market. Even as high quality products as corrugated pipe, made ??from a cheap alloy with application of rather difficult technology, is not without its drawbacks. Apparently, it is worth talking not so much about the shortcomings, how much about the peculiarities of the use of high-tech products. What to consider, working with stainless corrugated pipe for heating system:

  • high cost. Stainless corrugation can not be cheap due to the complexity of manufacture and high cost of raw materials;
  • tendency to accumulate dust in the recesses, which reduces heat dissipation and can affect the health of individuals, in contact with products;
  • high heat transfer, that requires, to avoid heat loss, additional insulation;
  • thinness of the walls, not designed for high mechanical loads. If necessary, a special cover is installed for protection;
  • the need for periodic inspection and maintenance of fittings, tightness control of connections, replacement of polymer elements;
  • undesirable installation of the system in a completely hidden form due to the presence of detachable connections, in which polymeric sealants are used. However, this fact does not matter when installing a heated floor;
  • desirability / the need to prevent the effects of electrochemical corrosion.

Installation of such a pipe is not difficult, there are special fittings for this

Another feature of corrugated stainless steel deserves to be studied, resulting from the presence of stiffeners, which is the resistance to the flow of the working medium.

pay attention! Purely theoretical, the corrugated pipe must have a higher hydraulic resistance, than smooth-walled, and give the fluid flow turbulence. However, practical evidence, that corrugated pipe, due to the described properties, cannot be used in gravitational systems with naturally circulating coolant, not provided.

The appearance of corrugated pipes in the arrangement of the heating system is unusual, to some it may seem anti-aesthetic. Note, products of different colors, therefore, there is room for design research. Of course, the appearance of corrugated stainless steel can be neglected, producing a hidden installation.

How to choose and install corrugated pipes for heating

When buying corrugated pipes, it is desirable to consider the labeling, applied to the wrapper of the bay, as it is not possible to print it on the surface of the product itself. Violation of the integrity of the container may be evidence of fraud, when there is a substitution of goods of lower value. And the difference in the cost of corrugated pipes, released by various manufacturers, is quite significant.

High-quality corrugated stainless steel pipe is distinguished:

  • ease of bending;
  • equality and intact seam;
  • uniformity of step;
  • absence of visually detectable defects.

Wrenches and tools are required for installation, which pipe will be cut at right angles. Fittings are recommended to choose brass, so that you do not have to periodically tighten the connection in the future. In brass fittings silicone gasket and comb ring provide perfect tightness.

The installation process is approximately as follows:

  1. Fittings are connected to plumbing fixtures. In places of connection, given the increased load, it is desirable to provide for the installation of supports.
  2. The pipes are cut into pieces of the desired length, the edges of the slices are checked for bumps and burrs.
  3. Inserting the corrugation into the fitting, tighten with nuts. If necessary, the pipe is gently bent at the smallest possible angle. It is highly undesirable to allow sagging corrugated stainless steel. Hidden sections of corrugated pipe, passing near the mains, it is recommended to protect the steel casing from electrochemical corrosion, which is generated by eddy currents.
  4. For giving the pipeline the required shape, it is attached to the wall surface.
  5. The operation of the mounted system under pressure during the test run is checked.

The use of corrugated stainless steel pipes for heating systems - not a cheap pleasure. But the output is a very efficient heating system, designed for decades of operation.