PE pipe municipal buried water supply construction scheme: hot melt connection and settlement response

PE pipe is widely used in municipal buried water supply due to its corrosion resistance and strong flexibility. During construction, it is necessary to focus on controlling the quality of hot melt connection and settlement measures to ensure long-term stable operation of the water supply system.

hot melt connection is the core connection process of PE pipe, and it is necessary to strictly follow the operation specifications. Before construction, the appearance of the pipe should be checked to ensure that there are no scratches, depressions, and the port is flat. When using a special hot melt welder, the heating temperature (usually 19010 ° C) and heating time should be set according to the pipe diameter specifications. After the heating plate shows a uniform molten state, quickly connect the pipe and maintain the specified pressure until the interface cools and solidifies. After the connection is completed, it is necessary to check whether the interface has formed uniform flanging, no virtual welding, leakage welding phenomenon, and carry out pressure test if necessary. The test pressure is not less than 1.5 times of the working pressure, and the pressure holding for 30 minutes without pressure drop is qualified.

For the common foundation settlement problems in municipal construction, prevention and control measures need to be taken from multiple links of design and construction. Before pipeline laying, geological survey should be carried out, and the soft soil layer should be treated with graded sand and gravel replacement, and the compaction degree should be layered to 90%. The pipeline foundation should be made of 150mm thick sand cushion, and concrete support piers should be added at the interface for reinforcement. When backfilling, plain soil or sand with a particle size of 50mm should be selected, and the layered backfill height should not exceed 300mm. A light roller should be used for compaction to avoid direct mechanical rolling of the pipeline. For crossing road sections or geologically complex areas, "pipe bridges" can be laid or bellows compensators can be set up to offset the settlement stress by using the flexibility of the PE pipe itself.

the construction process also needs to pay attention to environmental adaptation adjustment. During winter construction, the pipe should be preheated to more than 5 ° C before hot melt connection to avoid low temperature brittle cracking; during high temperature in summer, shading measures should be taken to prevent the pipe from thermal expansion and deformation. At the same time, make construction records, including hot melt parameters, foundation treatment data, settlement observation results, etc., to form a complete technical file to provide a basis for later operation and maintenance. Through the scientific application of hot melt connection technology and settlement prevention and control technology, the safety and durability of the PE pipe water supply system can be effectively improved to meet the long-term operation needs of municipal engineering.