CHAIN CONVEYOR REMELT INGOT CASTING IMPROVEMENT

摘要

Millions of tonnes of aluminum are produced on open mouldchain conveyor ingot casting machines every year. Operatorsand thus manufacturers of these machines are interested inreducing the oxide levels in the ingots and reducing productioncosts by improving productivity. In addition to optimization ofthe current process through increased understanding, CAST hasdeveloped two patented technologies for ingot casting; a lowdross filling system (CASTfill) and a mould design(CASTmould) with reduced ingot solidification time allowing20% productivity increase. This paper describes themethodology used and application of various mathematicalmodels including Smooth Particle Hydrodynamics (SPH).Protype filling system designs were tested on a full scale pilotsystem. The ingot/mould interface heat transfer was studied andmeasurements made of air gap formation and moulddeformation on a purpose built rig which duplicates machineconditions. Relatively simple 2D inverse and 3D thermal modelswere used to gain insight by conducting simple sensitivitystudies. The air gap formation controls the heat flow and thesolidification time. Investigations were made into the use ofhelium. Alsim, a fully coupled 3D thermal stress model capableof predicting ingot and mould deformation and air gap formationwas also applied to the problem. New mould designs wereproposed and tested on the rig. Following successful planttesting both CASTfill and CASTmould have been adopted at anumber of smelters.