How to prevent longitudinal expansion and contraction of pipes and fittings

The thermal expansion and contraction of pipes and fittings during winter or summer construction can easily damage PE pipes and fittings, so it is necessary to prevent longitudinal expansion and contraction of PE pipes and fittings. Spiral seam submerged arc welded pipe

The pipe fittings should be laid in a serpentine pattern in the trench, with slight curvature and expansion allowance. When installing PE pipes, try not to install expansion joints or use double disc short pipes instead of expansion joints. During the production of PE pipe fittings support piers and anchor piers, both sides should be simultaneously poured with concrete in one go. The bottom foundation of PE pipe fittings must be filled with a fine sand cushion layer and not less than 100mm. After the installation of PE pipe fittings, the backfilling work on both sides and 500mm above the pipe top must be done well, and the backfilling compaction coefficient must not be less than 95%.  

When installing pipes and fittings in hot weather, construction should be carried out as early as possible from night until 8:00 in the morning. After the atmospheric temperature is low and the pipeline is appropriately contracted, backfilling and final interface connection should be carried out. The pipes must be compacted layer by layer to prevent significant internal stress damage caused by thermal expansion and contraction of the pipeline.