In situ investigations on forces and power consumption during flow forming process

Abstract

Flow forming is used to manufacture high precision seamless components for aerospace and defence industries. The typical applications are rocket missile case, cartridge case, rocket nose cones etc. In flow forming, the deformable workpiece is placed over rigid mandrel and rigid roller(s) deform it under contact zone. There are two approaches used for production i.e. forward and reverse. In forward approach, the roller feed and deformation direction are same. Whereas in reverse approach, the roller feed and deformation directions are opposite. The power consumption during the process is an important aspect to foster energy efficient production environment. Also, forces encountered on the tool (Roller) are also crucial aspect in order to design tooling for different material and geometrical conditions. Based on literature review and industrial survey, it was observed that online force and power measurement are quite difficult in commercial machines. Hence, experimental and numerical studies have been carried out on force(s) and power consumption to promote environment conscious manufacturing. Design of experiment (DOE) approach was used to reduce experimental runs. Taguchi L36 design was used to conduct experiments. Three levels of three operating variables like speed, feed and reduction percentage along with two levels of two roller parameters like attack angle and nose radius were considered during the study. It was observed that speed and feed are the most important factors which are influencing the power consumption. Even, roller attack angle, nose radius and reduction percentage are mainly affecting force(s). Also, the results of experiments and simulations are found in good accordance.