TECHNOLOGICAL ASPECTS OF THE INDUCTION HARDENING OF INTERNAL ROTARY SURFACES OF SHIP JOINTS

The surface hardening by induction heating has many advantages over other methods of conventional thermal processing. It is known that this method is applied to achieve high hardness in the surface layer maintaining a resilient core. The implementation of the required thermal cycle depends both on the characteristics of the material undergoing processing and of the parameters of the system of induction impact. Some difficulties arise in high-frequency hardening of internal cylindrical surfaces of ferromagnetic joints with relatively small diameters, as there is a pronounced the Ring effect, leading to displacement of the eddy currents in the detail and to reduce the efficiency, and hence the quality of the products. The purpose of this work is to study the technological aspects of the induction hardening of internal rotary surfaces.