Production technology

. For the manufacture of poles, we use the northern pine harvested in the winter period in the area above the 60º north latitude. Raw materials for the production of wooden poles for power transmission lines are provided to FWIP LLC from the North-West region, namely from the Arkhangelsk, Vologda, Kirov, Kostroma, Leningrad regions, and the Komi Republic. Only high-quality raw materials come to debarking and surface finishing.

Selected poles enter the debarking process, during which the bark and the upper layer of bast (2-3 mm) are removed from the workpiece, after which the pole becomes clean and smooth. After debarking, the poles are classified, re-inspected to determine the hidden defects of wood and mechanical damages. Further on, the pole is sized down, the required technological holes are drilled.

Before impregnation, the wood is dried to an equilibrium moisture content of no more than 25%. Only after this requirement is met, the poles can be impregnated to the full depth of the sapwood. The drying process is completely automated and is carried out in drying chambers. Some of the poles are dried naturally. Through natural drying during the three summer months, the moisture content of the wood is reduced to the required 25%.

The impregnation of wooden poles is carried out in automated autoclaves using the vacuum-pressure-vacuum technology, a high-quality solution free from impurities and a chemically stable CCA (chromium, copper, arsenic) antiseptic manufactured by Osmose. The power transmission line wooden poles absorb the antiseptic at a rate of at least 12 kg per 1 cubic meter of the sapwood (in terms of dry matter).

After impregnation, each batch of poles undergoes a thorough final inspection. With the aid of a hollow drill, the depth of impregnation is determined (at least 10 samples per batch). Only if all the quality indicators meet the specifications, the poles are labelled with tags with the information about the manufacturer, batch number, impregnation date, antiseptic applied, pole class and length.

If necessary, our power transmission line poles are equipped with special transponder chips. The implementation of transponders (chips) into the pole body allows for the electronic certification of the entire power transmission line, determination of the pole effective lifetime, as well as planning of prompt repair works on the line.