Manufacturing method of high-weather-resistance cold-rolled steel strip with yield strength of 340 MPa

The invention belongs to the technical field of steel rolling, and particularly relates to a manufacturing method of a high-weather-resistance cold-rolled steel strip with the yield strength of 340 MPa, which comprises the following steps: 1) KR desulfurization; 2) converter smelting; 3) LF refining; 4) continuous casting; (5) casting blank inspection; (6) casting blank heating; (7) rough rolling; 8) finish rolling; (9) laminar cooling; 10) hot rolling and coiling; 11) pickling; 12) cold continuous rolling; 13) continuous annealing; (14) flattening; (15) trimming; and 16) coiling a finished product. The mechanical property result of the obtained high-weather-resistance cold-rolled steel strip finished product is that the yield strength is larger than or equal to 340 MPa, the tensile strength is larger than or equal to 460 MPa, and the percentage elongation after fracture A50 is larger than or equal to 28%; the corrosion rate of the obtained high-weather-resistance steel strip is within 58% relative to that of