Study of geometrical parameters of flanged edges of holes formed by thermal drilling with a combined tool

Abstract

Currently, sheet metal parts are widely used, involving fastening of various components to them using a threaded fastener. As a rule, the sheet thickness is not sufficient for shaping the minimum required number of threads, ensuring reliability of the fastener. To increase the length of unscrewing, various methods are used: sheet bending, welding of bushings or nuts, stamping in closed and open dies, etc. These methods are not technologically advanced. This problem can be solved using the method of thermal drilling of holes - the process of shaping holes by plastic deformation in sheet blanks with a temperature effect from friction forces of the tool on the workpiece. The main problem is the lack of available data on the geometric parameters of the obtained flanged edges in the available reference books. These data are needed to determine the number of threads in the hole being shaped and the strength of the threaded fastener. The article examines dependences of the geometrical parameters of flanged edges on cutting modes and sheet thickness as a result of thermal drilling.