Production of extremely deep sleeves by backward cold extrusion

摘要

The production of extremely deep sleeves by backward cold extrusion has drawn significant attention and interest in recent years in metal forming area, due to their unique and superior properties and their economic and technological advantages. This work describes the limitation related to buckling of extrusion punch during backward extrusion process and also represents the design of a new tool concept to avoid such risks of effects. Application of this tool concept for many cases in industry provides new opportunities to produce deep sleeves with ratio of the overall height of a sleeve (H) to its inner diameter (d) higher than three within one process stage by backward cold extrusion. Developed concept of tool has been supported by previous fundamental and applied research studies.