In the process of laying pipelines for hot and cold water supply, such components and materials are used as: a metal isolation plug, a metal
isolation plug with an output cable, a bellows compensator, a damping mat, a ground carpet, a T-shaped key, terminals, a joint insulation kit.
At the request of the customer ball valves are completed with T-shaped keys. The T-shaped key is designed to provide the operating positions
of the locking element of the ball valve in the PUF insulation. The length of the T-shaped key depends on the type of ball valve and the depth
of the pipeline. During operation, it is prohibited to increase the installed lever of the key turn. The hexagonal head of the T-shaped key has the
following dimensions: s = 32, 27, 19 mm.
The ground carpet is an elongated cone with a lid that opens from the top and a locking device in it to prevent unauthorized opening, since this product is installed in public residential areas - the places of laying pipelines in the FPU isolation of an underground non-channel gasket. The assignment of a ground carpet is to protect the zone of permanent the location of insulated cables from pipeline components in the insulation polyurethane and attached terminals inside the enclosure to which and connected from intrusion.
The body of the ground carpet is made of a steel pipe (usually 273 mm in diameter) and serves to house the cables and devices of the OCD system with pre-insulated polyurethane foam (PPU) pipes. For durability, the body of the product is covered at the factory or during installation by an insulating anti-corrosion coating. For stability and prevention of subsidence under the carpet, a concrete cushion is usually produced, and the base is filled with sand similar to the technology of pouring pipes in PPU insulation.
The inner wall of the carpet is fastened from the end and intermediate elements of the PPU pipeline to the output cables connected to the switching terminals of the remote-control system. Cable entry from the pipeline elements is carried out either through the bottom of the carpet, or through the bottom hole in the body of the product.
Set for insulation of the joint
To date, one of the most effective ways to protect the butt joint of the PPU pipeline is the use of heat shrinkable couplings, into the joint cavity of which polyurethane foam is poured. The reliability of such a PPU insulation joints is due to the quality of this substance and subsequently formed foam.
It is necessary that the materials with which the PPU insulation joints are carried out have not only certificates of conformity, but also certificates of passage of tests.Only in this case, high quality materials will be guaranteed. Work on the insulation of joints should be carried out at a temperature of at least -10 ° C. Preliminary it is required to connect the signal conductors, as well as to conduct appropriate measurements of the state of the wire system and thermal insulation.
The practice of laying and operating polyurethane foam pipes has shown that the quality and reliability of the installed pipeline system depends in many respects on the quality of the isolation of the pipe junctions. Thus, accidents caused by leakage of joints account for almost 30% of the general lack of installation and operation of heat-insulated pipelines. Therefore, reliable isolation of pipe joints from the influence of external aggressive media is of great importance. For these purposes, a special kit is used to seal the joints.
- clutch heat shrinkable;
The compensating mat (damping) is a polymeric foam material, most often - foamed polyethylene, supplied in the form of sheets with a size of 2000x1400x15 mm and used to protect the polyethylene sheath (PE) of pre-insulated pipelines in the polyurethane foam insulation of an underground non-channel gasket in accordance with GOST 30732-2006 from abrasion against the ground in places of constant stresses of the heating main.
Polyethylene compensating mats are fastened to PPU pipes in places where PPU bends, turns and U-shaped compensators are laid, on separate straight sections of the heat and water supply pipeline for additional protection of the polyethylene sheath from friction against the ground, which reduces the likelihood of damage to the external insulation of the pipeline PUR during operation with regular displacements of the heat conductor of the non-channel gasket.
Installation of polyethylene mats is carried out at the final stage of laying pipes in polyurethane foam insulation - after installation of heat shrink sleeves and before sanding the pipeline of the heating network.
Dimensions: height = 1400mm; length = 2000mm; thickness = 15mm.
Metal insulating plug
According to its purpose and functions, the metal isolation plug refers to auxiliary products used in the process of assembling shaped elements and pipes in polyurethane insulation. In the practice of pipeline construction, insulation plugs are used to solve two problems:
protection of thermal insulation from polyurethane foam (PPU) pre-insulated pipeline
temporary dampening of the steel pipe at the end point of the pipeline.
In the first case, both steel insulation plugs and cross-linked polyethylene plugs can be used.
In the second case, if it is necessary to shut off the internal flow through the pipes, only the steel plugs of the pipeline are used.
Metal insulation plug is a part of such shaped elements of the pipeline in PPU insulation according to GOST 30732-2006, as:
- a pipeline element with an output cable,
pipeline element with output lead cable
is included in the combined product at the ends of the PPU pipe and shaped elements (fixed supports, PPU bends and other products).
Installation of a metal (or polymer) insulation plug is made during the production of pipes and shaped products with industrial polymer insulation at the manufacturers of this type of pipe products.
Supports are one of the main elements of the pipeline. Supports sliding supports the pipeline, but do not prevent its movement from temperature deformations. They only perceive vertical loads from the mass of the pipeline to the product. An example of the conventional designation of a sliding support for a pipe of external diameter 325 mm in galvanized shell 450 mm: Sliding support 325-PPU-OCS-450.
Bellows expansion joint
If it is impossible to use natural compensation on the routes of the channelless laying, the bellows expansion joints are used in the polyurethane foam insulation.
To connect the signal conductors and connect the monitoring devices, you must use the following types of terminals:
- terminal terminal - at the control points at the ends of the pipeline;
- terminal terminal with output to a stationary detector - at the control point at the end of the pipeline in which a stationary detector is provided;
- intermediate terminal - at the intermediate point of pipeline monitoring;
double terminal terminal - at the control point at the border of the site;
uniting terminal - at those control points, where it is necessary to combine two (three) sections of the pipeline into a single loop;
pass-through terminal - for connection of connecting cables in places of absence of insulation (in thermal chambers, in cellars of houses, etc.) and at length of a connecting cable more than 10 m.