Abstract: The cracking of hot melt joints is due to the fact that the parameters used in construction welding do not meet the actual welding parameters of the pipeline, or the welder does not meet the requirements. If the pipe body bursts, if the test pressure meets the requirements, it is the problem of the pipe itself. For example, the problem of brittle cracking is serious, and plastic cracking may be an accident of production control.
Polyethylene(PE for short) is a thermoplastic resin made by polymerizing ethylene. In industry, it also includes copolymers of ethylene and a small amount of α-olefins. Polyethylene is odorless, non-toxic, feels like wax, has excellent low temperature resistance, good chemical stability, and can withstand most acids and alkalis. It is insoluble in general solvents at room temperature, has low water absorption and excellent electrical insulation. The mechanical properties of polyethylene are general, the tensile strength is low, the creep resistance is not good, and the impact resistance is good. Polyethylene can be processed by blow molding, extrusion, injection molding and other methods, and is widely used in the manufacture of films, hollow products, fibers and daily sundries.
Pipes are devices that are connected by pipes, pipe couplings and valves to transport gases, liquids or fluids with solid particles. Generally, the fluid is pressurized by blowers, compressors, pumps, boilers, etc., and then flows from the high pressure of the pipeline to the low pressure. It can also be transported by the fluid's own pressure or gravity. Pipes have a wide range of uses, mainly used in water supply, drainage, heating, gas supply, long-distance transportation of oil and natural gas, agricultural irrigation, hydraulic engineering and various industrial installations.
Why does the PE water supply pipe burst?
There are two different situations when a hot-melt joint cracks and a tube body bursts.
The hot melt joint cracking is due to the fact that the parameters used in construction welding do not match the actual welding parameters of the pipeline, or the welder does not operate as required.
If there is no problem with the hot-melt joint of the pe water supply pipe, but the pipe body bursts, if the test pressure meets the requirements, it is the problem of the pipe itself. If the problem of brittle cracking is serious, plastic cracking may be an accident of production control.
The pressure of the PE pipe itself on the soil at the bottom of the trench is very small, and the bottom soil can withstand these pressures, so the formation does not need to be specially reinforced. However, if the pipe passes through old ponds, depressions and other places, it needs to be reinforced, otherwise the PE water supply pipe will split due to uneven settlement.
During the construction process, we may also encounter PE pipe bursts caused by gas in the pipeline. Assuming that the pressure in the pipe is not firm, the gas volume will change. Once the pressure in the PE water supply pipe drops, the gas in the pipe will change accordingly, which will impact the pipe wall and easily lead to splitting. It is very likely that the test water pressure is much greater than the design pressure.
In addition, quality accidents caused by incorrect construction methods of construction workers often occur. Therefore, welding procedures and operating specifications are extremely important. In addition to choosing regular and qualified manufacturers, strengthening the quality inspection of PE water supply pipes and improving the quality of construction are also what we should focus on.
PE water supply pipe has been widely used because of its excellent performance, and it is the best pipe to replace steel water supply pipe. However, there are also many problems in the construction process. Standard operation can largely avoid the burst of the water supply pipe.