Prefabricated and directly buried type supplied by the manufacturer Thermal insulation pipe ：
Prefabricated directly buried insulation pipe has the following characteristics in structure: 1. It is fixed inside Steel pipe Flow on Bracket Friction with the inner wall of the outer casing, the thermal insulation material moves with the working steel pipe, and there will be no mechanical wear and pulverization of the thermal insulation material. 2. The outer steel pipe has high strength, good sealing performance, and can effectively waterproof and impermeable. 3. The outer wall of the outer sleeve steel pipe is treated with high-quality anti-corrosion treatment, so that the service life of the anti-corrosion coating of the outer sleeve steel pipe is more than 20 years. 4. The thermal insulation layer of the working steel pipe is made of high-quality thermal insulation materials with good thermal insulation effect. 5. There is a gap of about 10-20mm between the working steel pipe insulation layer and the outer steel pipe, which can be used for further insulation. Direct burial again The Conduit ***To provide a smooth channel for tide discharge, so that the tide discharge pipe * * * can discharge tide in time and act as a signal pipe at the same time; Or it can be pumped into a low vacuum, which can more effectively insulate the heat and reduce the corrosion of the inner wall of the outer sleeve. 6. The rolling bracket of the working negative pipe is made of special low heat material, and the friction coefficient with the steel is about 0.1. The friction resistance of the pipe during operation is small. 7. The fixed support of working steel pipe, rolling support and working steel pipe are connected by special design, which can effectively prevent the generation of pipeline thermal bridge. 8. Fully sealed structure is adopted for drainage of directly buried pipeline Water pipe It is not necessary to set another inspection and connection at the low point of the working steel pipe or the position required by the design. 9. The elbows, tees, bellows compensators, valves, etc. of the working steel pipes are all arranged in the steel casings. The whole working pipeline operates in a fully sealed environment, which is safe and reliable. 10. The concrete buttress can be completely fixed externally by using the internal fixation support technology. Save costs and shorten construction period. 11. The vacuum technology can be used to basically eliminate the electrochemical corrosion caused by water on the inner wall of the outer steel pipe, and further improve the insulation effect of the pipe.
Prefabricated directly buried insulation pipe supplied by the manufacturer:
The prefabricated polyurethane directly buried insulation pipes, winding FRP polyurethane directly buried pipes, prefabricated high-temperature composite polyurethane directly buried pipes, steel sheathed steel directly buried pipes and other products produced by the company have been recognized by the national quality inspection * * *, and can * * undertake the design and construction of large-scale insulation projects. For a long time, our products have been widely used in industrial and mining enterprises, petrochemical enterprises, urban central heating pipe networks, residential areas and other fields throughout the country, and have been highly praised by users.
Product parameters and installation acceptance of polyurethane directly buried insulation pipe
Inner working pipe
The inner working pipe of directly buried thermal insulation pipe of cold and hot water can be used
Seamless negative pipe, stainless steel pipe, galvanized steel pipe, PPR steel pipe, glass steel pipe, plastic lined steel pipe.
Process flow and production process flow diagram configuration -->rust removal of steel pipe surface -->bracket installation -->installation of outer sleeve -->head -->mold installation -->transmission of foaming workbench -->opening of injection holes and exhaust holes -->foaming injection A B glue -->Head removal -->Pipe end treatment -->Product self inspection -->Factory mark and certificate -->Qualified products leave the factory
Specification, model, nominal diameter "DN", outer diameter of steel pipe × wall thickness, outer diameter of outer protective pipe × wall thickness, insulation thickness mm, nominal diameter "DN", outer diameter of steel pipe × wall thickness, outer diameter of outer protective pipe × wall thickness, insulation thickness mm
20 27×3.0 95×2.5 31.5 150 159×4.5 238×3.0 36.5 25 32×3.0 100×2.5 31.5 200 219×6.0 310×4.9 40.6 32 38×3.0 110×2.5 33.5 250 273×7.0 365×5.6 40.4 40 48×3.0 125×3.0 35.5 300 325×8.0 420×5.6 41.9 50 57×3.5 125×3.0 31.0 350 377×9.0 475×7.8 41.2 70 76×4.0 142×3.0 30.0 400 426×10.0 530×8.8 43.2 80 89×4.0 155×3.0 30.0 450 478×10. 0 587×8.8 45.7 100 108×4.0 170×3.0 30.5 500 529×10.0 655×9.8 53.2 125 133×4.0 200×3.2 30.0 600 630×10.0 760×11.1 53.9
notes
1. The thickness of insulation layer and the size of outer sleeve of directly buried pipeline will change according to the temperature and pressure parameters of medium.
2. The company also provides elbow, tee, reducer, drainage device and other pipe fittings and fixed supports corresponding to the specifications of directly buried pipes.
3. Can also accept orders with special requirements from users
Performance parameter 1 Steel pipe - an internal working pipe for transporting hot water or steam or used as a steel casing for injection. The rust removal grade of the steel pipe surface should reach Sa2.5 grade. Seamless steel pipe according to the standard GB/T 8163-1999 Spiral seam steel pipe GB 3067-2008 GB/T9711.1/1997 Straight seam steel pipe GB/T 3092-1993
2 Polyurethane rigid foam foam - insulation layer project unit index density Kg/M2>=60 compressive strength Mpa>=0.3 thermal conductivity W/M * k<=0.033 heat resistance C<=120 or<=150 water absorption%<=10 void%>=88 pipe stacking and storage
1. The pipe storage site shall be flat, free of sundries and ponding, and have sufficient bearing capacity.
2. The pipes shall be placed 2m away from the heat source and equipped with fire-fighting facilities.
3. Pipes must be laid with pipe sleepers. The width of the pipe sleepers should be greater than 150mm and the height should be greater than 100mm. When storing, pipes of the same type should be placed together. 12m long pipes should be placed in a whole block layer by layer from the ground. It can be stacked for a short time. Each layer may not be placed as a whole, but the height shall not be greater than 1.5m.
4. Pipes shall be sealed at both ends during storage. When stored in the open air, they shall be covered with felt cloth. No sun exposure or rain is allowed. Pipe stacking and safekeeping Correct handling method Wrong handling method
1. Pipes shall be hoisted with slings wider than 50mm.
2. During loading and unloading, it shall be lifted steadily and placed gently to prevent collision.
3. During unloading, vertical lifting method should be used for truck loading and container loading. Forklift trucks and loaders can be used for cooperation.
4. It is forbidden to use iron tools to pry or steel wire rope to bind the outer casing directly for pipe stacking and hoisting. Trench excavation and backfilling for the installation of polyurethane directly buried insulation pipes shall be carried out in accordance with the Technical Operation Specification for Water Supply Pipeline Engineering Construction and design requirements.
The trench size of directly buried pipeline shall meet the requirements
1. When the bearing capacity of the upper layer at the bottom of the trench is ≤ 60KPa, the bottom of the trench shall be padded with plain concrete.
2. The bottom soil layer of C15 plain concrete layer shall be compacted first and then poured with concrete. The surface of concrete layer shall be smooth and flat. When the bottom soil layer is collapsible soil, it shall be replaced (about 1.0m deep) and compacted.
3. The width and * * * of the trench at the joint in the trench shall be 250 × 300mm more than that at the non joint.
4. The position with corrugated compensator and the soil layer elevation at the bottom of the corrugated compensator shall be determined according to the actual arrival size of the compensator.
5. The slope of the upper layer of the trench bottom along the pipeline shall be consistent with that of the pipeline.
6. 100mm around the directly buried pipeline shall be compacted with fine sand. The diameter of sand particles shall not be greater than 8mm. There shall be no clay, brick, stone, iron and other sundries in the sand layer.
7. When the pipe is located in the highly corrosive soil section such as slag and sundries, the backfill shall be replaced with less corrosive soil and compacted layer by layer.
8. The ditch must be well drained. Drainage ditch and water pump can be used for drainage.
Installation of pipelines The installation of pipelines must be carried out after the excavation of the pipe trench and the treatment of the soil layer at the bottom of the trench are qualified.
Pay attention to the following requirements during installation
1. Before the pipeline is laid into the trench, the anti-corrosion coating on the surface of the pipeline shall be carefully checked. If the anti-corrosion coating is damaged, it shall be treated in time.
2. The design axis and gradient of the pipeline shall be ensured when the pipeline is connected.
3. Prefabricated insulation pipes can be hoisted into the trench for installation, or two or more * * * pipes can be hoisted after welding. When the assembled and welded pipe section is long, two or more cranes should be used to lift the pipe and lower the pipe. The position of the lifting point should be selected according to the balance condition. It is strictly prohibited to push the pipeline directly into the trench.
4. After the welding of the working steel pipe is completed and the inspection is qualified, the heat preservation of the joint and the connection of the outer sleeve can be handled. The formwork can be erected first for polyurethane foaming, and then the joint part can be sealed as a whole with heat shrinkable tape. Both ends and the straight pipe can be lapped by 100mm respectively. Or the outer sleeve can be butt welded and opened for foaming after the sealing inspection is qualified.
5. When the project is completed on that day, the pipe end shall be blocked with a blind plate to prevent mud and water from entering the pipe.
6. Prefabricated insulation pipes can be installed in three ways: cold installation, thermal prestress installation and one-time compensator installation.
7. Cold installation is to directly connect the pipe sections and backfill according to the standard after passing the inspection
8. For the installation of thermal prestress, the pipeline shall be preheated to 60 ℃ of the working temperature for welding, and then backfilled and compacted.
9. The disposable compensator must be welded when the pipeline temperature rises to 60 ℃ of the working temperature, and then backfilled and compacted.
Project acceptance The project quality acceptance of directly buried heat supply pipeline project shall not only meet the relevant requirements of the design drawings and the Code for Construction and Acceptance of Urban Heat Supply Pipe Engineering CJJ28, but also include the following contents
The acceptance of civil works mainly includes the following aspects: the excavation section size of the pipe trench, the foundation treatment of the soil layer at the bottom of the trench, the slope and aspect of the pipe trench, the size and compactness of the sand layer around the pipeline, the height and compactness of the backfill., The acceptance of installation works mainly includes the deviation of pipeline axis, the slope and aspect of pipeline installation, and the welding quality of the butt joint of the work pipe, which must meet the requirements of the design and relevant specifications. If the design requires that the hydrostatic test be carried out on the construction site, the work pipe should be subject to hydrostatic test, and the outer casing joint coating should be subject to air tightness test before foaming, The test pressure is 20Kpa, and it is qualified if there is no leakage in the soapy water inspection. The integrity of the anti-corrosion coating of the prefabricated insulation pipeline jacket, such as the preset heat tracing cable or * * * line, should confirm the correctness of its wiring and its insulation.
