Cooling Properties Of Spray Quenching Equipment

With the rapid development of industry, in the heat treatment area,the increasingly high demand for the cooling effect is requested, the traditional way of quenching is making the workpiece structure more complex and making the production cost is increasing. Because of these advantages include uniform cooling rate, controllable, adjustable cooling capacity range, security, and no pollution, other forms of quenching is difficult to compare the advantages, in recent years more and more attentions are paid to spray quenching and itself has great practical significance and research value. In this paper, we will try to provide some guidance for the design of spray quenching equipment though studying spray quenching system of the surface of the workpiece.First, Volumetric flux distributions is the most important spray parameter who affect the quality of spray quenching for the workpiece is pointed out in the paper and then volumetric flux distributions model for the spray affected area on the curve surface of a workpiece is established. Impact area refers to the individual nozzles to the curved surface area, The spray impact zone on the surface of the curve workpiece is elliptical in shape. The size of this zone can be increased by increasing the orifice-to-surface distance, requiring fewer nozzles to quench workpiece's circumference.Secondly, based on the finite volume method and using nonlinear estimation method, heat transfer coefficient of the surface of the workpiece with spray quenching is solved in this paper, taking into account nonlinear material parameters and latent heat, and make the relevant experimental verification, the results demonstrate that reverse method for heat transfer coefficient which is provided in the paper is trustworthy.Finally, based on the experiment the spray quenching furnace was developed, using Ansys software and taking heat transfer coefficient on the surface which was solved by the method provided in the paper as the boundary loading conditions, the spray quenching temperature field of the workpiece is simulated. The impact of pressure and the distance from nozzle mouth to quench surface against hardening process is studied, the results showed that:Increasing the nozzle pressure drop or decreasing the orifice-to surface distance causes the transitions to the lower temperature boiling regimes to occur at higher surface temperatures. More close to the internal points of the workpiece showing more gentle, slower quenching rate.