Design of a Multihole Porthole Die for Aluminum Tube Extrusion

Abstract

Currently, the design of extrusion dies is usually carried out on the basis of experience and corrected after a number of trial extrusion runs before becoming usable. Thus, it is difficult to guarantee product quality and productivity when the profile structure is complex, and actual production has to be stopped or postponed, especially for multihole extrusion dies. This work analyzes the design of a multihole extrusion die for producing an aluminum tube and investigates the effects of number and layout of portholes on extrusion process. Firstly, four multihole dies with three, six, seven, and nine portholes are designed, respectively. Then, extrusion processes with different multihole dies are simulated by means of HyperXtrude. Based on the results of the numerical simulation, metal flow, temperature distribution, welding pressure, extrusion load, die stress, etc. are analyzed and compared. Through analysis, Die 1 (with three portholes) is the optimum one among these four dies, where the uniform velocity distribution, maximum welding pressure, minimum required extrusion load, and minimum die stress are obtained. Finally, the design methods for multihole extrusion dies are summarized.