Heating network designs

The project adopted a channelless laying of the heating network and in cases, insulated from prefabricated polyurethane foam with ODK with longitudinal drainage. Types of heating network gaskets and structures are adopted in accordance with album A-397-80 and album 313-TS-007.000 "Standard solutions for laying pipelines of heating networks in insulation from polyurethane foam Du50-1000". The sections of the heating network laying are shown in Fig. TS-4. See the plan of the heat network route and the wiring diagram on the drawings: SP-1, TS-2. The project provides for an open method of laying heating networks, trench-by-trench restoration of pavements with an overlap of the top layer of asphalt concrete for 2,0 m in both directions beyond the trench boundaries. The type of pavement was adopted in accordance with the agreement. In accordance with the act of inspection of the existing heating network: TK-1, TK-Pr., TK-2, TK-3, TK-4 - walk-through thermal chambers without equipment are subject to dismantling. In thermal chambers TK-9K5, TK-9K2, TK-9KZ-1, replace equipment within the boundaries of the project and floor slabs. For the installation of the heating network in the project, steel pipes were adopted in accordance with the “Rules for the Design and Safe Operation of Steam and Hot Water Pipelines”, approved by the Gosgortekhnadzor of Russia in 2003 and guidance materials RM-TG-II (094) - 98. Compensation for temperature elongation of pipelines is carried out by bellows compensators and due to natural compensation at the angles of rotation of the heating network route. At the lowest points of the heating network, it is planned to install devices for draining water from the system, and at the highest points, installation of air vents. Pipes pre-insulated at the factory are calculated for a service life of 25 years, provided that the quality of their installation is ensured, as well as the quality of the network water that meets the standards of hot water boilers. To ensure the service life of the SC for 25 years, the content of chlorides in the network water should not exceed 15 mg/l. The heating network belongs to the IV category of pipelines. Temperature > 115°C to 250°C. Pressure more than 0,7 to 16 kgf / cm2 - Table No. 1 "Rules for the design and safe operation of steam and hot water pipelines." According to the reliability of heat supply, heat consumers belong to the second category - consumers who allow a decrease in temperature in heated rooms for the period of emergency response, but not more than 54 hours: residential and public buildings up to 12°С; industrial buildings up to 8°C. To fix the pipelines in the sections between the compensators, it is planned to install shield fixed reinforced concrete supports and metal fixed supports. In accordance with the calculation of loads on fixed supports, the project adopted: NO-3,5,12 (DuYuOO) - panel fixed support in polyurethane foam insulation with the UEC system. H 0-1,7,8 (DuYuOO) - a monolithic fixed support in polyurethane foam insulation with the UEC system. NO-13 (Dn700) - panel fixed support in polyurethane foam insulation with the UEC system. NO-4,6 (DuYuOO) - metal fixed supports in thermal chambers. In accordance with SNiP 2.04.07-86*, installation of instrumentation for manometers and thermometers is designed in places where sectional fittings or branches are installed. Details of pipelines are accepted in the project in accordance with TD 5.903-13. "Products and details of pipelines of thermal networks". For the maintenance of shut-off valves and drain devices, the project provides for the reconstruction of heating chambers from prefabricated reinforced concrete in accordance with album 3.903 class 13 v.1 and Al. "SK" LGTS. In thermal chambers, a complete replacement of pipelines, fittings (ball valves), metal structures, stairs and hatches is provided. After installation of the equipment, thermal insulation is provided by PPU spraying. Prefabricated panel fixed reinforced concrete supports are manufactured by CJSC ZHBI-6 of the St. Petersburg Construction Corporation, in accordance with series 3.903. class-14 in. 1-4. The associated drainage of the heating network is designed from asbestos-cement drainage pipes 0200. The release of water from the bottom of the chambers and the emptying of pipelines are provided through intermediate wells into the storm sewer with the installation of valves of the “Clap” type according to the A-397-80 album. The project provides for the installation of drainage water outlets with a flow rate of 3.59 l / s into the nearest existing manholes of the public sewerage system. Periodic discharge of water cooled to <40°C from emptying the heating network (2 times a year for 4 hours, 1 time per day) with a flow rate of 1329,2 mXNUMX/day is carried out into the nearest existing and planned manholes of the public sewerage system. The project provides for the use of pipelines with thermal insulation made of polyurethane foam with UEC brand 345 with a waterproof coating of polyethylene in accordance with TU 5768-001-27519262-97 applied at the factory by analogy with the album 313 TS-002.000 JSC "Association VNIIPIENERGOPROM" and "Standard laying solutions pipelines of heating networks in insulation from polyurethane foam Du50-1000”. Joints should be insulated by pouring. Reinforcement insulation in the chambers is designed. For passive protection of pipelines of the heating system from electrocorrosion, the installation of electrically insulating movable and fixed supports is provided. The project of active protection against electrochemical corrosion is not required. The design of the UEC system has been completed - see the UEC.ECP section. The design heat network is crossed by existing engineering networks (water pipelines, public sewer pipes, telephone sewerage, electrical cables). Work on laying heat pipelines at intersections with utilities should be carried out in accordance with the current norms and rules of SNiP 3.01.01-85 and the technical conditions and conditions for approval by network owners. Excavation work in the buffer zone of existing communications is allowed only with the written permission of the organization responsible for their operation. Work near the networks should be carried out under the direct supervision of the engineer, and in the immediate vicinity - under the supervision of a representative of the operating organization. Trench development near existing underground structures are done manually. When opening communications, it is necessary to take safety precautions in case of a possible violation of their isolation. If any underground structure is damaged, old damage is discovered, as well as underground structures not indicated on the drawings, it is necessary to stop work, inform the owner and the State Administrative and Technical Inspectorate. At the intersection with the designed pipelines, the existing ones are hung on wire twists to the beams laid across the trench. If communications are found that are not specified in the project, earthworks should be stopped and representatives of the customer and the designer should be called to the site. Under the bottoms of the chambers, intermediate drainage wells, crushed stone preparation 100 mm thick is provided, shed with bitumen until full saturation. Under the fixed supports, a concrete base 100 mm thick is provided on crushed stone preparation 100 mm thick, shed with bitumen until completely saturated. As part of the implementation of the program of measures to ensure the reliability of operation of heating network sections with an increased probability of failures during the heating season, a temporary heating network was built.