Thick-walled steel pipes are primarily used in water supply projects, petrochemical industry, chemical industry, power industry, agricultural irrigation, and urban construction. They are used for liquid transportation: water supply and drainage. For gas transportation: coal gas, steam, liquefied petroleum gas. For structural purposes: pile pipes, bridges; wharfs, roads, and pipes for building structures. Common materials for thick-walled steel pipes in China include: 10#, 20Mn, 42CrMo, 36CrMo, 40Cr, 20Cr, 15CrMo, 12Cr1Mov, Q235A, Q235B, 0Cr13, 1Cr17, 00Cr1.