The working project is intended to increase the energy efficiency of the centralized heating system of consumers by reconstructing the main heating networks from the boiler house "Gigant" on the section TK-158–TK-139, which are characterized by high rates of heat energy losses and unsatisfactory technical condition. Additional land acquisition is not required. When performing major repairs of old external heating networks, it is planned to: -replace existing pipelines of external heating networks with the use of pipelines pre-insulated with polyurethane foam elements with a conductive steel pipe and an outer shell made of polyethylene or metal resistant to atmospheric corrosion (according to DSTU B V.2.5-31:2007); -replacement of existing pipelines in thermal chambers using straight-seam electric welded steel pipelines (according to DSTU 8943:2019) and hot-deformed seamless (according to DSTU 8938:2019) pipelines; -replacement of existing and installation of new shut-off valves, compensators in thermal chambers; -thermal insulation of pipelines and valves in thermal chambers; -repair and reconstruction of thermal chambers and construction of drainage wells if necessary; -replacement of impassable channels (precast concrete trays); -provide for the implementation of a remote control and monitoring system for thermal network pipelines (SDKM) with the installation of control devices. -restoration of road surfaces and sidewalks in places where external thermal network pipelines are laid; -performance of landscaping and improvement works in the area of work. According to the results of engineering and geodetic surveys, the diameters of the existing steel pipelines laid in the channel: -from TK-158 to TK-156 are Du 400; -from TK-156 to TK-155 are Du 400 and Du 500; -from TK-147 to TK-141-A are Du 500; -from TK-141-A to TK-139 are Du 400. Temperature schedule - 115-70⁰С. The maximum design pressure in the heating network is P=1.6 MPa. Consumers connected to the designed network in terms of heat supply reliability belong to the second category. The operating mode of the centralized heating system is seasonal, only for heating needs (without DHW). The surrounding development is represented by a complex of non-residential and residential buildings. The territory under consideration has existing landscaping and landscaping. The relief of the territory under consideration is planned in accordance with the planning of the adjacent territory. The natural and climatic characteristics of the site, which belongs to the II architectural and construction climatic region (according to DSTU N B V.1.1-27:2010 "Protection from dangerous geological processes, harmful operational influences, from fire. Construction climatology"), are characterized by the following data: - the average temperature of the coldest five-day period, with a provision of 0.92 - (minus 21ºС); - annual precipitation from 400mm to 500mm, average - 475mm. The direction of the prevailing winds: - in the summer - eastern; - in winter - north. Average wind speed in January - 4.7 m/sec. The climate of the region is moderate. Summer is hot and dry with dry winds, winter with frequent thaws, the average air temperature is 8.5°C, the average temperature of the warmest month is July +22.3°C, the coldest month is January -3.4 ºC. According to DBN V.1.2-2:2006 "System for ensuring the reliability and safety of construction objects. Loads and impacts. Design standards" the characteristic values of loads and impacts: - snow load - 1110 Pa; - wind load - 440 Pa; - ice wall thickness - 19mm; - wind load during ice - 260 Pa. As a result of the overhaul of heating networks, the quality indicators of heat supply to consumers will be improved and the following results will be obtained: -minimizing the frequency of damage to heating network pipelines on the TK-158–TK-139 section by replacing old pipelines with new ones; -reducing the loss of thermal energy and energy resources by using pre-insulated pipelines; -providing uninterrupted and high-quality heat supply services to the consumer.

This work project provides for the replacement of pipelines in the area from the beginning of the impassable channel near TK-158 to TK-139, which includes: -replacement of existing pipelines of external heat networks using pipelines pre-insulated with polyurethane foam elements with a conductive steel pipe and an outer shell made of polyethylene or metal resistant to atmospheric corrosion (according to DSTU B V.2.5-31:2007); -replacement of existing pipelines in thermal chambers using straight-seam electric welded steel pipelines (according to DSTU 9219:2023) and hot-deformed seamless (according to DSTU 8938:2019); -replacement of existing and installation of new shut-off valves, compensators in thermal chambers; -thermal insulation of pipelines and valves in thermal chambers; -repair and reconstruction of thermal chambers and construction of drainage wells at the lower points of the route; -replacement of impassable channels (precast concrete trays); -it is planned to implement a system for remote control and monitoring of heat network pipelines (SDKM) with the installation of control devices. - see volume 2, set KTM-24.02-ATM. -restoration of road surface and sidewalks in places of laying pipelines of external heat networks; -implementation of works on landscaping and improvement of the territory of the work. To reduce heat loss in the existing heat network on the section from TK-158 to TK-139, for pipelines provided for by the detailed design in impassable trays, it is planned to install pre-insulated pipelines with thermal insulation from polyurethane foam in a protective polyethylene shell. Thermal insulation is selected according to series 1, the diameter of the pipeline is ST/PE 630x8 mm/800 mm. The coefficient of thermal conductivity of polyurethane foam is λ≤ 0.035 W/m °C. For pipelines and pipeline fittings in thermal chambers, a thermal insulation layer is provided, 110 mm thick, made of mineral wool insulation, covered with foil-coated polyethylene foam insulation tape.