When the product is cooled in the annealing furnace, the steel is cooled at a slow speed. In the annealing furnace section, the nozzle is divided into five cooling zones in the width direction of the strip steel to control the different cooling air in each zone to uniformly cool the strip steel. This gives a better plate shape. The role of the rapid cooling section is to quickly cool the strip.

In order to evenly cool the annealing furnace, two adjacent coolers are reversed. The circulation fans at the top of each cooler pull out the atmosphere in the annealing furnace. After passing through the heat exchanger, the atmosphere gas exchanges heat with the circulating water. After being cooled, it is then pressed into the annealing furnace through the circulation fan ducts. The bottom nozzle is sprayed onto the strip.