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Installation of NPVC pipelines must be conducted in compliance with active standards on civil engineering, rules about building utility systems and other legal requirements.
When installing a pipeline, the decrease of total pipeline length due to assembly by bell-mouth connection should be taken into consideration (see the table below for details on the bell length).
| Pipe diameter d, mm |
Bell length, mm |
|
110 |
116,0 |
| 160 |
134,5 |
|
225 |
154,0 |
| 280 |
172,0 |
|
315 |
184,0 |
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Depending on physical and chemical properties of transported matter and purpose of pipeline, cast-iron fittings can be used.
In winter installation process (including assembly of pipeline joints with rubber gaskets) can be conducted only if the temperature is higher than 10°С below zero.
Pipes are connected so that the bell-mouths faced the flow of transported matter.
NPVC pipes are resistant to any soil conditions and require no corrosion protection.
NPVC pipes cannot be coated with corrosive paints or solvents and buried under material full of aromatic carbohydrates, paints and/or solvents.
For appropriate and quick installation of NPVC pipes, a well-prepared trench is necessary.
The trench must be of optimum depth to exclude the possibility of freezing-through of the pipeline. 1,00 to 1,80 m range will meet this requirement in most cases, though local climatic and soil peculiarities should be taken into consideration. The width of the trench depends on the outer diameter of the pipes (see picture for details).
If the trench bottom is dry and firm with no sharp stones, then there is no need for any special pipeline bed. If the soil is rocky or full of stones, the pipes should be laid on a bed of sand, loam or small stones. This matter must be laid 0,15 m thick and, besides, tamped down well. In dangerous points protective concrete and clay barriers partitions should be mounted to prevent the trench from collapsing. Then the space around the pipe is filled to provide sufficient resistance from all sides. The previously excavated soil can be used to finish covering. It can be sand with stones not more than 20 mm across. Compaction is done manually or using vibrator.It is crucial not to leave hollow spaces under the pipeline.The trench is subsequently filled with soil, if the parts are maximum 300 mm in size. Joints and the whole pipeline are covered with soil only after a positive impermeability test..
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