Analysis and optimization of cooling channels performances for industrial extrusion dies

Abstract

Liquid nitrogen cooling is widely used in the extrusion industrial practice in order to increase the production rate, to reduce the die temperature and to avoid defects on the profile exit surfaces resulting from an excessive heating. However, the efficiency of the cooling is deeply affected by position and design of the liquid nitrogen channel so that numerical modelling is gaining an increasing industrial interest in relation to the possibility offered to optimize the channel design without expensive and time-consuming experimental trials. In this work, a numerical FE model developed within COMSOL Multiphysics® is proposed and validated against experimental trials performed in industrial environment. The model combines the 3D simulation of the extrusion process with a 1D model of the cooling channel thus allowing the testing of a number of different solutions at the die design stage. The global aim of this work is the assessment of the liquid nitrogen cooling efficiency in the extrusion of an industrial aluminum profile and the proof of the potentials offered by numerical models to get an optimized channel design in terms of cooling efficiency, die thermal balancing and reduction of liquid nitrogen consumption.

Assessment of the Optimization Strategy for Nitrogen Cooling Channel Design in Extrusion Dies

“…The experimental campaign and the validation of the numerical model implemented within the COMSOL Multiphysics for the selected case of Fig. 1 were presented in detail during the ESAFORM 2021 Conference [11]. Therefore, only the main data are here synthetically recalled for the sake of clarity of the present work.…”

“…Fig. 2 The tooling set: a) the mandrel; b) the die; c) the backer [11] 100% of nitrogen flow rate, while during the last two extrusion the nitrogen flow rate was significantly reduced (30% and 20% respectively).…”

“…The authors of the paper have still proposed a numerical model for the thermal field prediction during the extrusion process, modelled as 3D, with nitrogen flowing in a simplified 1D channel [9][10][11]. These works provided the basis for the present paper, in which the FE model of the cooled extrusion process was integrated within the optimization platform, modeFRONTIER®, with the aim to automatically detect the optimal channel design.…”

A novel combo‐transmission system of cold energy and electricity for aluminium profile production: Using liquid nitrogen and superconductor technologies

“…31 A numerical model is used to optimize the channel design in terms of the cooling efficiency, die heat balance, and reduction of liquid nitrogen consumption. 32 To efficiently install the cooling channels as close as possible to the bearing region, conformal cooling channels manufactured by selective laser melting (SLM) are implemented in the die designs. [33][34][35] Based on our best search of the literature, most studies focus on theoretical analysis, technical simulation, and performance improvement of liquid nitrogen cooling technology for aluminium profile extrusion.…”

“…A numerical model of AA6060 extrusion process was carried out to predict and optimize the nitrogen cooling effect in the die 31 . A numerical model is used to optimize the channel design in terms of the cooling efficiency, die heat balance, and reduction of liquid nitrogen consumption 32 . To efficiently install the cooling channels as close as possible to the bearing region, conformal cooling channels manufactured by selective laser melting (SLM) are implemented in the die designs 33–35 …”