Economy type X70 pipeline steel and producing method thereof

An economical type X70 pipeline steel of the invention mainly contains the following components in weight percent: 0.015 to 0.060 of Carbon, smaller than or equal to 0.30 of Silicon, 0.7 to 1.80 of Manganese, less than or equal to 0.015 of Phosphorous, less than or equal to 0.050 of Sulfur, 0.01 to 0.05 of Aluminum, 0.001 to 0.004 of Calcium, less than or equal to 0.006 of Nitrogen, greater than or equal to 0.04 and less than or equal to 0.15 of Niobium, greater than or equal to 0.005 and less than or equal to 0.020 of Titanium, and the remaining components are Ferrum and other inevitable purities element. Less than or equal to 0.08 of Vanadium, less than or equal to 0.50 of Chromium, less than or equal to 0.50 of Molybdenum, less than or equal to 0.60 of Copper, less than or equal to 0.60 of Nickel which are in weight percentage can be added into the steel. The economical type X70 pipeline steel of the invention has the advantages of the low production cost, the excellent comprehensive mechanical performance and the good welding performance, the simple production process, the short fabrication period, promoting the labor efficiency and the rolling yield, and being applied in various metallurgy enterprises.