Miscellaneous

Air ducts made of galvanized steel. Classification. design advantages

June 29, 2020

Galvanized air ducts are used in supply ventilation systems, as well as in air conditioning systems, duct, roof and central. Usually, they are installed there, where we have to take into account the difficulties, associated with the influence of such factors, as the presence of fire danger, smoky, high pressure, fever, aggressive, in terms of chemical activity, environment.

Galvanized steel is a durable and non-corrosive material, one of the best options for the production of air ducts for various purposes

How to classify air ducts, made of galvanized steel

It is customary to distinguish between air ducts, made of galvanized, on several parameters. In the first place, based on the shape of the cross section. According to this indicator is allocated:

  • rectangular air ducts made of galvanized steel. Such constructions, usually, have a small cross section and wall thickness (usually set within 0,5-1,5 mm), given the potentially lower air supply, assumed to be smaller, than round devices.

On a side note! Rectangular galvanized air ducts are considered to be more advantageous in terms of compact placement and aesthetic appeal, which avoids additional costs for camouflage and decoration.

  • round. No restrictions, related to the size of the product. Rectangular devices are superior to a number of significant indicators, which includes functional efficiency and cost, simplicity and speed of installation works.

Depending on the connection method, used in the installation of the duct:

  • bandage. It is applied only at round section;
  • nipple (coupling);
  • rosette;
  • welded;
  • rebate;
  • flanged.

Air ducts differ in the shape of the section, it determines the method of their connection

The scope dictates the granting of specific properties to structures, that's why they happen:

  • flexible;
  • fireproof;
  • semi-rigid;
  • heat-insulated. A special insulating layer is provided in the complete set.

Based on the peculiarities of the design, it is customary to speak of devices:

  • straight seam;
  • spiral winding;
  • spiral-welded.

Depending on the speed of movement of the air environment structures can be:

  • high speed (with the speed of air movement more 15 m / With);
  • low speed.

Technical characteristics and the certificate of conformity provide operation at a certain working pressure. It is also one of the parameters, used in the classification of air ducts by this parameter:

  • high (from 2 kPa);
  • secondary (from 9 GPA to 2 kPa);
  • low (to 9 GPU).

Features of a design, arising from the appointment

Production of air ducts from galvanized steel originally arose as caused by the needs of the Navy, but the versatility of the design has allowed the device to spread to many other areas, including industrial and domestic.

Ventilation systems made of galvanized steel can be found everywhere - in public places, residential buildings, at enterprises

The use of galvanized is caused, mostly, complexity of conditions, in which the ventilation equipment is to be installed. Extremity of operation is set:

  • aggressive chemical environment;
  • high working pressure;
  • significant temperatures;
  • the presence of an open hearth, therefore, an increased limit of fire resistance of air ducts is required, withstanding five-hundred-degree temperature according to SNiP;
  • specific climatic features.

Useful to know! Ventilation is installed in accordance with the rules, established SNiP 41-01-2003 and SNiP 11-33-75, as well as a number of technical specifications, mainly, 36-736-93 and other regulations.

Production of air ducts from galvanized steel allows to carry out installation of supply ventilation:

  • in the living space, office or public house;
  • shopping, warehouses and production facilities.

Installation can be carried out for the purpose:

  • remove smoke, formed at the location of the source of high temperature, which becomes possible, as in a design there is a strong steel sheet;
  • to produce natural or forced ventilation of premises;
  • ensuring the operation of the system outside the buildings. The presence of a protective layer, made of zinc, allows to maintain influence of open air, UV radiation, precipitation.

Laying the system is not always possible in a straight line, when you can do without the use of pipes. In conditions of limited space, when you need to make a significant number of turns and go around corners, widely used shaped elements:

  • inserts;
  • crosses;
  • taps;
  • adapters;
  • tees, etc.. P.

Air ducts have different configurations, corners are used to give the desired shape, taps and other shaped elements

Modern industrial production of galvanized air ducts

Relative ease of production requires qualified personnel, who has the skills to control a computerized process. Building codes and sanitary regulations strictly regulate production, for which certificates are issued.

When using straight seam pipes 1,5 — 2,5 meters, usual for private homes, where a large length is not required, but a significant number of shaped elements will be required, the edges of the steel sheet are fastened, using a nipple or flange. Execution of cutting at reception of the standard sizes is conducted automatically, when receiving a task with specially set parameters, special equipment is connected. In the streets, the workpiece is turned into a tube with a given diameter, coming to process the longitudinal edge on the folding mill.

pay attention! The air duct from straight seam galvanized pipes in comparison with rectangular will manage cheaper, will be easier to install and show better aerodynamic properties.

A strip of galvanized steel is used to make spiral winding pipes 137 mm. It is twisted in a spiral, connecting a seam inside fastening on lock type. To obtain a product with a cross section:

  • v 130-350 mm take a sheet with a thickness of 0,55 mm;
  • v 360-800 mm - thickness in 0,7 mm;
  • v 850-1250 mm - millimeter.

The thickness of the metal sheet, which is taken to make the product cross section from 850 mm, should be at least 1 mm

The standard length of such a spiral winding pipe, manufactured in the factory, is equal to three or six meters, at special wishes of the customer it can be changed (to 12 m).

Products with a spiral seam are characterized by high performance:

  • strength;
  • rigidity, provided by the ribs;
  • ease, as the weight of the structure is reduced due to the use of thin steel sheet;
  • tightness (class P).

When the air passes through the spiral winding pipes, additional rotation appears in it, which increases the speed and reduces the noise level.

Having received the made pipes without a joint on one corner, further work is carried out in several stages:

  • the connection is made on a special machine;
  • equip the necessary rounding;
  • supplied with facade and other elements, to send to the customer.

Production is carried out in strict accordance with SNiP, certificate of quality - the presence of constant demand.

Advantages and disadvantages of air ducts, made of galvanized steel

Prevalence of air ducts, for the manufacture of which galvanized steel was used, due to a combination of several advantages, extracted by the consumer at installation of a design from such material.

Galvanized ducts are easy to install regardless of the shape of the section

Among the benefits are listed:

  • slight load on the structure of the room or building, where the installation is performed;
  • structural strength and resistance to aggressive environments;
  • the presence of excellent aerodynamic characteristics;
  • easy and fast installation, which is facilitated by the insignificance of the weight of the structure and the presence of a wide range of shaped parts. Delivery to the installation site will also not be difficult;
  • insignificance of expenses for additional carrying out of sound insulation and, if necessary, thermal insulation;
  • high heat resistance and ability to withstand the effects of open flames;
  • relatively low cost, which is much lower, than other metal analogues;
  • ease of maintenance of the installed structure;
  • guaranteed service life, which is at least ten years. The presence of a galvanized layer saves costs, associated with additional priming and painting. Even under the influence of street air, the development of corrosion processes will slow down significantly;
  • versatility, that allows to establish a design in rooms of different function and out of buildings, as well as adapt it to individual characteristics of the location.

Constructions with a round cross section are characterized:

  • higher aerodynamic qualities;
  • lower cost;
  • lower transportation and storage costs;
  • ease of care, especially, cleaning;
  • simplicity and cheapness of installation.

Installation of an air duct of a rectangular design allows:

  • choose the right configuration, taking into account the limited space, placement is possible in the presence of a false ceiling;
  • to achieve the aesthetic appeal of the room without the use of any additional funds or decorative elements, masking the design.

The list of shortcomings of galvanized steel ducts is limited to just a couple of items:

  1. Significant mechanical actions can lead to deformations, which disrupt the ventilation system. I am not free from this shortcoming ??no similar design, performed, as of metal, and from other materials.
  2. The interaction of air with the galvanized surface produces characteristic unpleasant subtle sounds, intensifying with increasing wind speed, which has contact with the structure, located outdoors.

The popularity of galvanized air ducts shows, that consumers are willing to ignore these shortcomings, as they are outweighed by advantages of a design. Variety of assortment, the presence of shaped parts allows consumers to choose a design option, optimal for installation in a specific object, whether it is a private household, industrial building, commercial or public purposes.