Heating process of ultra-low carbon steel billet

The invention relates to the technical field of metal processing, in particular to a heating process of an ultra-low carbon steel billet. A heating process of an ultra-low carbon steel billet comprises the following steps that a target steel billet sequentially enters a first heating section, a second heating section, a third heating section and a soaking section to be heated; wherein the heating temperature of the first heating section is 500-900 DEG C; the heating temperature of the second heating section is 860-1000 DEG C; the heating temperature of the third heating section is 940-1040 DEG C; and the heating temperature of the soaking section is 960-1020 DEG C. The heating time of the target steel billet in the soaking section is first preset time, the total heating time of the target steel billet is second preset time, the first preset time is longer than or equal to 30 min, and the second preset time is longer than or equal to 180 min. The heating process of the ultra-low carbon steel billet can be suit