Production method of hot rolled steel coil

The invention relates to a production method of a hot rolled steel coil, comprising the following steps of: (1) designing components, preprocessing molten iron, then smelting in a converter, switching between nitrogen and argon, and tapping to obtain molten steel; (2) continuously casting the molten steel to obtain a plate blank, wherein the molten steel quantity of a tundish when the continuous casting tundish is stopped to be poured is controlled at 8-15t, and the liquid level is controlled at 200-350 mm; protecting the pouring in the whole process, wherein the inserting depth of a long water gap is 300-400 mm; (3) heating the plate blank; and (4) finally, rolling the heated plate blank and curling to obtain the hot rolled steel coil. With the production method, the contents of C and Mn in the components of Q235q-E steel are reduced, in addition, by adopting a proper rolling process and a cooling control process, the combination property of the Q235q-E steel is enhanced, and a Q235q-E hot rolled steel coil with low cost and high performance is produced.