Deformation in the graphitized cathodes and on the shells of aluminum reduction cells

Deformations in the cathode and on the shell of aluminum reduction cells were systematically investigated in laboratory and industrial cells. The sodium expansion coefficient was obtained from test data. Numerical simulation was utilized to study the stress fields of the cathode and the shell, which took not only the sodium expansion chemical stress but also the temperature gradient thermal stress into account. The displacements of the shell during cell heating treatment and after start-up were acquired. The deformation on the shell of a 350 kA cell with the graphitized cathode has been monitored and measured for 360 d with a mechanical displacement meter. It is found that the simulation values are in good agreement with the measured ones.