Slurry feed line steel with good low-temperature toughness and manufacturing method thereof

The invention provides slurry feed line steel with good low-temperature toughness and a manufacturing method thereof. The slurry feed line steel with good low-temperature toughness comprises 0.10 to 0.20% of C, 0.10 to 0.30% of Si, 0.80 to 1.50% of Mn, less than or equal to 0.018% of P, less than or equal to 0.004% of S, 0.010 to 0.035% of Ti, 0.02 to 0.05% of Als, less than or equal to 0.006% of N and the balance Fe. The manufacturing method of the slurry feed line steel with good low-temperature toughness comprises smelting, continuous casting and hot rolling. When a plate blank is heated to a temperature of 1160 to 1300 DEG C, the plate blank is subjected to a first-stage controlled rolling and a second-stage controlled rolling, wherein an initial temperature of the first-stage controlled rolling is in a range of 1130 to 1200 DEG C; an end temperature of the first-stage controlled rolling is above 1020 DEG C; an initial temperature of the second-stage controlled rolling is below 1000 DEG C; and an end temperature of the second-stage controlled rolling is in a range of 780 to 880 DEG C. The plate blank subjected to the first-stage controlled rolling and the second-stage controlled rolling is cooled at a speed of 5 to 20 DEG C per second and then is reeled at a temperature of 550 to 680 DEG C. The manufacturing method of the slurry feed line steel with good low-temperature toughness has the advantages that the slurry feed line steel with good low-temperature toughness does not contain precious alloy elements such as Nb, Mo, V and the like so that an alloy cost is low; S content and P content are controlled strictly so that good low-temperature toughness of steel is guaranteed effectively; and a controlled rolling and controlled cooling technology is utilized for crystal particle refinement so that a pearlite microstructure is uniformly distributed and good steel strength matching with toughness is guaranteed.