What is line pipe? What are the differences from common steel pipes?

Pipeline pipes are steel pipes manufactured in accordance with API 5L, GB/T 9711 and other special standards. They are specially used for long-distance transmission of oil, natural gas, water and other fluids, and have special requirements on strength, toughness, weldability and corrosion resistance. Ordinary steel pipes are subject to general structural or low-pressure fluid transmission standards, with low technical requirements, and cannot directly replace pipeline pipes for high-pressure oil and gas transmission.