Research on Precision Die Forging Utilizing Divided Flow : Second report, Experimental study of processes utilizing flow relief-axis and relief-hole

Abstract

Possibility of the proposed cold precision die forging processes utilizing the principles of the flow relief-axis and relief-hole is experimentally examined and compared with the theoretical results presented in the first report⁽¹⁾. By applying these processes, the working loads and pressures can be reduced remarkably and a complete filling up of materials into die cavity can be attained successfully. In the process utilizing the flow relief-axis principle, there exists an optimum diameter minimizing the working pressure. On the other hand, in the process utilizing the flow relief-hole principle, the pressure decreases monotonously as the diameter of the relief-hole increases and becomes less than that in the former process. The thickness of the product finally obtained is larger in the process utilizing the relief-axis principle than that obtained in the process utilizing the relief-hole one. Thus, the former is preferable for saving materials.