Techniques of measuring spray-cooling homogeneity

The cooling homogeneity is one of the most important factors that must be considered in the design of cooling sections for the hot rolling of thin sheets.Inhomogeneous cooling can lead to undesirable thermal distortion.The cooling homogeneity is mainly influenced by the water distribution of the cooling section.And so, one way to measure the cooling homogeneity is to measure the impact-pressure distribution of the cooling section.Another way is to measure the surface-temperature distribution of a steel sample during the cooling process.There are two ways to measure the surface temperature and the temperature field: the contact and non-contact measurements.The contact measurement can be performed with thermocouples and the non-contact method is an optical measurement like the one using an infrared scanner.Each of these methods has their advantages and disadvantages.Their comparison was made during an experimental measurement of the cooling of a stainless steel sheet using full-cone water nozzles and a special linear pneumatic sprayer.