Extruder Automation Comes of Age: A Review and Outlook of Automation for Aluminum Extruders

摘要

Automation systems have entered the territory of extrusion in which measurement and control of the temperature of the extruded profile at the die exit are crucial tasks. Non-contact temperature measurement pyrometers provide the means for the control via the inputs billet temperature and/or the ram speed. Automation for an aluminum extrusion system based on iterative learning control (ILC) as presented in ET 1996, and also other commercially available automation systems, have been installed and are in use in a number of aluminum extrusion plants. Automation offers production gains and increased product quality, yet its proliferation has been slow. Reasons vary from inadequate furnace control to disinterested crew, albeit some installed systems continue to yield spectacular gains. Factors governing these phenomena are dealt with in the paper, and issues concerning the deployment and the exploiting of the potential of automation systems are analyzed; basis is information and experience obtained from installed and operating systems. Finally, a method for estimating the optimal initial settings of an extruder equipped with ILC for a new profile is given. The estimates can be used for production cost estimating and planning.