Experimental Study on the Blanking of Thick Wall Metal Tube
In this paper, we present a comprehensive experimental study on the blanking process of thick wall metal tube. The tube used in experiment is GCr15 bearing steel with 56 mm in outer-diameter and 6.5 mm in wall-thickness. The experiment was conducted with an experimental blanking apparatus, which consists of fixed die, moving die and inner cores rod. Two blanking schemes, single punching and cross punching, are compared through experiment. The single punching scheme is realizable for tube blanking but the effect is not acceptable in recent stage. Cross scheme is a better choice for tube blanking as the surface roughness in blanking section can be greatly improved. In cross scheme, the first penetration depth is the key factor to final blanking quality. It was found through experiment that the adequate first penetration depth is around 60 percent of the wall thickness of the tube.