Line pipe is a pipe used to transport liquid and gaseous fuels such as petroleum, natural gas, water and oil. ‌It is mainly transported by underground burial and is mainly used in the oil and gas industry. Line pipes can be divided into two types: seamless welding and seam welding according to different connection methods. Seamless welded line pipes have good air tightness but poor flexibility and are suitable for long-term fixed routes; while seam welded line pipes can be changed in direction by plasma cutting machines, but have poor air tightness.