Abstract: Device for the accelerated cooling of a continuous substrate moving rapidly in a vertical plane, formed by a closed chamber, which includes, in succession in the direction of travel of the substrate, at least one so-called main cooling zone provided with coolant injectors, a so-called secondary cooling zone promoting contact between the coolant and the substrate, a coolant extraction zone and coolant retainers both at the inlet and outlet of the cooling device. The main cooling zone includes, spray injectors for forming one or more water/air fog curtains arranged in space so that they come into direct contact with the substrate to be cooled.