Currently, more than 85% of the world's crude oil and 99% of natural gas are transported through pipelines. The total mileage of oil and gas pipelines has exceeded 3.8 million kilometers. Compared with railway, road, waterway and air transportation, pipeline transportation has the following characteristics:

①High efficiency. The annual transport capacity of a 1220mm pipeline is about 100 million tons, which is equivalent to the annual transport capacity of two double-track railways.

②Low cost. The cost of transporting the same amount of petroleum products is less than half of rail transport.

③ Strong continuity. The use of closed conveying can continuous and stable operation for a long time.

④The square tube is easy to manage. It able to remote centralized control, the system automation degree is high, and the equipment maintenance is small.

Pipeline transportation also has its limitations. It is not flexible and convenient as ships and other transportation, and the products that can be transported are more diverse, so it is mainly suitable for large-scale, one-way, fixed-point transportation of fluid.