A Novel Technique for Combining Conventional and Flow Spinning with Simultaneously Burnishing Processes

In this research, new Technique was developed to perform three different operations in the same stroke, namely conventional spinning, shear spinning (wall thickness reduction) and burnishing processes. Experimental work was conducted and confirmed the success of the presented technique. The response of the product quality and required load to process parameters such as rotational speed (46,76,150 and 230 rpm), axial feed (0.15,0.3,0.6 and 1.21 mm/rev), burnishing load (20, 25 and 30 KN), distances between shear balls, and distance between burnishing balls was checked and clarified. The results showed that, the optimum condition for forming load and surface roughness occurred at rotation speed at 150 rpm, axial feed 0.3 rev/mm and burnishing load 25 KN. The surface roughness of the new technique products has been found to be about 0.41 µm and the forming load not more than 6 KN at optimum case. When distance between the shear balls increases, the forming load decrease until it reaches its lowest level at 2 mm, and any further increase in this distance increases the process load. Hardness and surface roughness increase with an increase of the distance between shear balls. It can be also concluded that the hardness and forming load increases with the increase of space between burnishing balls. However, the surface roughness improves with increasing burnishing balls distance.