In recent years, international research, development and application of X80 grade seamless pipeline steel for international transportation of natural gas have been carried out. The main results are as follows:


1. Development Trend of Natural Gas Pipeline
High-pressure transportation and selection of high-grade steel pipes can greatly save pipeline construction costs, which is the main trend of natural gas pipeline development. The diameter of pipeline can be reduced by using high-pressure transmission. By developing and applying high-grade pipelines, the wall thickness of steel pipe can be reduced, the weight of steel pipe can be reduced, the welding time of construction site can be reduced, and the weight of steel and construction cost can be greatly reduced. According to the statistics of pipeline construction in Canada, the use of X80 steel can save 17% to 29.5% compared with X70 steel in pipeline materials and engineering design.


In the world, X80 grade seamless pipeline steel has been successfully applied. Since the mid-1980s, X80 steel grades have been studied and tested in batches in the early 1990s. So far, about 2000 km of X80 steel pipes have been used all over the world.


3. The world's main pipeline steel pipe product standards are X80 steel grade, and have clear quality and technical indicators. Japan, Europe, Canada and other countries have a large number of production and supply records, production technology has become increasingly mature.


4. X80 steel pipe is mainly concentrated in Canada, Europe, the United States and other developed countries. It has accumulated rich experience in pipeline design, construction and operation management.


5. Successful experience of research and application of international grade X80 steel shows that there is no significant difference between X80 and X70 steel in design, production and construction, and the pipeline has been completed and operated normally.


In summary:
(1) Choosing X80 high-grade pipeline can save a lot of pipeline construction costs, which is an important trend of international natural gas pipeline development. X80 steel is a mature and standard pipeline steel level in the world. It has mature experience in pipeline design, production, construction and operation in the world.


(2) After years of research and development in China, the quality index of X80 seamless pipeline steel pipes has been tried for the first time to meet the requirements of X80 pipeline engineering application standard that the physical quality of steel pipes is in the same level as that of similar products abroad.


(3) It solves the problem of fault control pipeline of international X80 natural gas transportation road. Based on the analysis of crack toughness and anti-crack toughness of X80 steel pipeline and the safety of pipeline operation, it is safe and feasible to replace X70 thin-walled X80 pipeline.


(4) X80 pipeline steel pipe will be more widely used in the world. The application of X80 pipeline steel pipe engineering is very necessary. It is suggested that X80 pipeline be the first choice for large-diameter high-pressure natural gas pipeline in the future.