While the infrastructure has been actively developing in the regions of Russia, there is a need for reorganization of existing and construction of new electricity networks. Energy system requires use of modern technologies that contribute to the higher performance in the energy industry.
GOC «Teplocentrstroy» provides a full range of services for designing and constructing of overhead power lines.
Design and installation of transmission lines are based on national standards and regulations, including obligatory implementation of safety rules in the constructing of electric power lines and performing electrical work.
Depending on the location andpurpose, electric power lines can be installed using steel (lattice and polyhedral) supports, metal and wooden supports.
Steel lattice supports
Steel lattice supports are used by constructing of the HV voltage 35-1150kV in urban and open areas, in the climatic icing and wind regions (I-V) with the lowest possible outside temperature up to — 65 °C.
Standard lattice supports can be single-shelf and multi-shelf, free standing and with braces, etc. Unified lattice supports for overhead lines are the spatial lattice structures consisting of a large amount of elements made of angular steel. The connection of these elements can be of two types: bolted or welded. Securing steel supports in the ground is done by their installation on the base.
The advantage of lattice supports is the savings in transportation due to the compactness, the ability to create structures for a very high mechanical loads, relatively low weight and high mechanical strength, workability to build on the slopes, as well as the supports are suitable for hot-dip galvanizing, which improves their performance characteristics, and expands the range of their applications.
The main advantage of wooden supports is their low cost.
These are widely used to support the transition of 6-10 kV overhead lines through natural obstacles and engineering facilities in rural areas, in I-IV areas according to wind and ice by temperatures from -40 to +40 °C., along the roads and highways of I-IV categories; railways, navigational and navigable rivers; pipelines and cableways.
To construct the supports, the wood in quality above the third grade is used.
According to the latest calculations, the average lifetime of wooden supports is from 15 to 20 years (larch), from 4 to 5 years (pine), and from 2 to 3 years (spruce).
The service life of supports can vary significantly depending on the climate, so a special attention is paid to their impregnation with antiseptics, that can increase the service life of wood up to 40 years.
Polyhedral steel supports
Polyhedral steel supports are the supports of new generation, that have been used in Russia for the past 10 years. Today, they are very popular in the constructing of the overhead lines in voltage of 10-500 kV.
Polyhedral steel supports are widely used in the distribution networks and networks of high voltage.
These supports are polyhedral conical structure made of steel sheets. The support may consist of one, two or more sections (depending on the desired height). Section length is up to 16 m. There are two types of connections possible: flanged and flat (telescopic). The height of supports may reach up to 40 meters or more, the wall thickness is from 3 to 12 mm and diameter up to 2 meters.
Supports are installed directly in the drilled well or are attached to the flanges to concrete bases, as well as they can be installed on bases made with the use of bored piles.
Polyhedral metal supports have several advantages over all other types of supports:
- High performance characteristics, especially in complex icing and wind conditions.
- Ability to withstand in emergency mode in 2-3 times higher than concrete supports.
- Polyhedral supports are several times lighter than concrete and lattice ones.
- Installation process does not require much space, which is especially important while working in urban and mountain areas.
- Standard polyhedral supports can be easily modified by increasing or decreasing the height, wall thickness, diameter etc.
- Lifetime of 50 years, the durability can be enhanced by polymer coating.
- Cost of construction of 1 km power lines is 25-50% lower than while using concrete and lattice supports.
A large variety of specifications of polyhedral metal supports allows their use in electric industry, rail transportation, road construction, utilities, by constructing telecommunication masts, etc.
Reinforced concrete supports
Reinforced concrete supports are more often used while installing outdoor lighting of urban sites, streets, living areas, industrial areas, airports, railway roads and highways, etc. and are indispensable by constructing of 0.4-110 kV overhead lines.
This type of supports has been used in the electricity network constructing for more than half a century. They are popular primarily due to the relative low cost of constructing. The overall figures show that the use of reinforced concrete supports for overhead line constructing outperforms steel lattice supports and they are almost as good as polyhedral ones.
These benefits include long service life (up to 40 years), anti-corrosion, durability, wind and cold resistance up to -55 °C, seismic resistance up to 9 points.