The invention discloses pipeline steel with good and stable low-temperature flexibility and a method for rolling
hot rolled coils thereof. The pipeline steel comprises the following compositions in percentage by weight: 0.03 to 0.070 percent of carbon, 0.19 to 0.30 percent of
silicon, 1.50 to 1.90 percent of
manganese, 0.010 to 0.020 percent of
titanium, 0.015 to 0.040 percent of aluminum, less than or equal to 0.30 percent of
nickel, less than or equal to 0.02 percent of
chromium, less than or equal to 0.0002 percent of
boron, less than or equal to 0.018 percent of
phosphorus, less than or equal to 0.005 percent of
sulfur, 0.002 to 0.003 percent of
calcium, 0.20 to 0.40 percent of
molybdenum, less than or equal to 0.30 percent of
copper, 0.02 to 0.10 percent of
niobium, less than or equal to 0.006 percent of
nitrogen, less than or equal to 0.004 percent of
oxygen, less than or equal to 0.00025 percent of
hydrogen, and the balance of iron and impurities. The manufactured pipeline steel has the characteristics that sigma s is equal to be between 565 and 580 MPa; sigma b is equal to be between 665 and 690 MPa; and sigma s / sigma b is less than or equal to 0.85.