Pipeline design experts share: Practical application experience of PE pipes in gas transportation projects

PE pipes, or polyethylene pipes, have many significant advantages over traditional metal pipes. The first is excellent corrosion resistance. Metal pipes are susceptible to corrosion from chemicals and stray currents in the soil, while PE pipes have stable chemical properties and are inert materials. Except for a few strong oxidants, they can withstand the erosion of a variety of chemical media. They do not require complex and expensive anti-corrosion treatment like metal pipes, which greatly reduces maintenance costs and safety risks.

Secondly, PE pipes are light in weight, and their density is only 1/8 of that of steel, which makes it easier to transport and lower pipes into trenches. Large lifting equipment is not required, which reduces construction difficulty and cost. At the same time, it has high strength and good toughness. Its elongation at break is generally more than 500%. It can withstand changes in the stratum without breaking. It has a strong adaptability to uneven settlement of the pipe base. It is a pipe with excellent seismic performance and performs well in dealing with special situations such as geological changes. For example, in the 1995 Kobe earthquake in Japan, polyethylene gas pipes and water supply pipes were the only pipeline systems that survived.

In terms of connection methods, PE pipes mainly use electric fusion connection and hot melt connection. The operation method is relatively simple. Construction personnel can master it after short-term training, and the welding quality is guaranteed, which can effectively ensure the sealing of the interface and reduce the risk of gas leakage. Moreover, in the gas pipeline network that has been in operation, PE pipes can also open three-way operations with gas, which is difficult to achieve with steel pipes.

From the actual engineering cases, in the gas renovation project of an old community in a certain city, due to the complex underground pipelines in the community and the narrow construction space, if traditional metal pipes are used, the construction is extremely difficult and easy to damage other pipelines. After using PE pipes, its excellent flexibility can be fully utilized. It can be laid in a winding manner according to the terrain or bent according to the terrain, easily bypassing obstacles and reducing the number of joints. At the same time, PE pipes can be prefabricated on the ground and then placed in the trench, reducing the amount of earthwork in the trench. In the end, the project was not only completed ahead of schedule, but also in the subsequent use, there was no gas leakage problem, and the safety of residents' gas use was effectively guaranteed.

In addition, in the construction of some urban gas pipelines, it is often necessary to cross roads and buildings. At this time, the use of trenchless technology combined with PE pipes has great advantages. PE pipes have large deflection, fast welding speed, convenient construction, and can minimize the impact on traffic and residents' lives.

PE pipes have shown many advantages in gas transmission projects, such as excellent performance, simple construction, reliable operation, convenient maintenance, long service life (up to 50 years), and low investment cost. With the continuous advancement and improvement of technology, I believe that PE pipes will play a more important role in future gas transmission projects.