DESIGN OF STEADY-STATE TEST APPARATUS TO EVALUATE HEAT-TRANSFER COEFFICIENT OF SPRAY

Recent years have seen a change in the emphasis on the importance of s trip cooling on the hot strip mill as it has been realised that the ra te of cooling affects the metallurgical and mechanical properties of t he finished strip. The degree of cooling applied both between the fini shing stands and on the runout table depends on the grade of steel bei ng produced. To meet customers' demands for increased quality and prod uct consistency, together with the production of a wider range of stee ls, there is a need for accurate temperature control throughout the wh ole cooling path. This requires a cooling system that couples the requ ired cooling rate with the heat transfer capabilities of the spray sys tem and the production speed and line length. The current work, being undertaken as an Engineering Doctorate project, considers the heat tra nsfer capabilities of various water cooling systems. This paper is an interim report which describes the design of steady state heat transfe r apparatus to evaluate the heat transfer coefficient of a single spra y and presents some preliminary results.