... 40Over-heat pipe for low and medium pressure boiler,boilling water pipe,locomotive somke pipe(big and small)Fluid pipe20, ... 5L/CT21.3-914*1.5-40Carrying gas,water or oil in the industries of petroleum and natural gasHydraulic prop ... gas, petroleum, chemical industry, electric power, metallurgy thermodynamic fields, water supply engineering, steam heating, hydroelectric power station and long pipeline ...