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Intra-shop pipelines are pipelines connecting the units of the unit or various devices and units located in the building. When installing intra-shop pipelines, cargo blocks, waists and polypasts used in conjunction with manual and electric winches are widely used, as well as telescopic retractable lifts, autohydro lifts, self-propelled retractable scaffolds and inventory suspension platforms.
During loading and unloading works and installation of nodes and blocks of pipelines in the design position, lifting machines (automobile, pneumowheel and tracked cranes, pipelayers) used in the installation of technological equipment and construction structures are used.
One of the responsible and time-consuming rigging operations associated with lifting and installing pipes, parts, fittings, nodes and pipeline blocks in the design position is their slinging. Loading should be performed by specially trained workers who are part of the integrated brigade. The location of the sling devices is chosen depending on the dimensions of the lifted loads, their weight and configuration, the number and characteristics of lifting means, as well as the lifting scheme. At the same time, it is necessary to know the position of the center of gravity of the nodes or blocks of the spatial structures of the pipeline and sling them so that the center of gravity is below the places of the sling along the axis of the sling separation, i.e. the possibility of turning the cargo around its axis is excluded. It is also necessary to take into account the convenience of decomposition after installing individual parts of pipelines in the design position.
Pipeline consolidation
At the installation site, the consolidation assembly of finished nodes into pipeline blocks is carried out. Assembling pipeline nodes into blocks reduces installation time, since these works can be carried out in parallel with construction work, when, due to the state of construction readiness of the facility, it is not possible to start installation of pipelines. Since the consolidation assembly is carried out on a specially equipped assembly site, i.e. in conditions where it is possible to mechanize the performance of all operations, higher labor productivity is achieved and the quality and safety of work is increased. In the process of assembly, the block is completed with all the necessary products.
The consolidation assembly of blocks is carried out in accordance with the project of production of works, and in its absence, decisions are made based on specific installation conditions.
The dimensions and weight of the blocks should ensure the convenience of their transportation to the place of installation and installation in the design position (the possibility of passage through the openings, between workshop metal structures, equipment, lines of other pipelines). The unit during lifting and installation must maintain the necessary rigidity and strength. In some cases, temporary connections are established to ensure the required rigidity.
The unit should include all the details that are provided by the working drawing of the pipeline (rebar, fittings and beans of control and control devices, fittings for drainages and airmen, etc.).
The number of welded and detachable joints performed at height should be minimal, while mounting joints should be placed in places convenient for assembly and welding. On vertical sections, mounting joints should not be placed, since their assembly is much more difficult than on horizontal ones.
The consolidation assembly of pipeline blocks is carried out on rigid, well-calibrated racks. For assembly, special stands and devices are used – conductors and centrators, ensuring the correct position of parts, components, pipes and fittings during welding. If installation conditions permit, the pipeline blocks are assembled together with the equipment and installed on a common frame.
The nodes are assembled into pipeline blocks after control measurements and checking the location of the connected connections at the equipment. Before consolidation assembly, temporary plugs and plugs are removed from the valves and nodes of pipelines, protecting their ends from contamination during storage and transportation, as well as the flanges and ends of the pipes are reopened. In addition, when enlarging, carefully check whether there are foreign objects inside the elements of the nodes.
Another way of disconnecting the connection is threaded. This method is often used when you need to connect steel pipes.
Carving is applied to steel pipes with a plaque or by cutting on a machine. If there is a need for threading on thin-walled pipes, it is applied by rolling.
The threaded type of connection can provide good strength and tightness (of course, subject to installation rules).
The threaded connection of steel pipes is good because it is convenient to assemble and, if necessary, dismantle the pipeline. No special tools are needed, only a wrench.
All locksmithing and welding work must be completed on the finished unit, thermal treatment of the joints (if required) is performed and the quality of welding is checked. The assembled unit should not require any fitting work at the installation site, so you must first make a control assembly of the mated blocks.
During consolidation assembly, thermal insulation of the blocks is performed on the assembly site. When transporting isolated pipeline blocks, measures are taken to prevent damage to the insulation.
Pipeline blocks from the assembly site to the installation site are served in order of their installation.
Installation of intra-shop pipelines is carried out in accordance with the following regulatory documents:
SNIP 3.05.05-84 Technological equipment and technological pipelines
VSN 362-87 Manufacturing, installation and testing of technological pipelines on Ru up to 10 MPa
SP 61.13330.2012. Thermal insulation of equipment and pipelines