The corrugated wall tank has to withstand all mechanical strains that occur during operation or transport of the transformer. Great experience gathered over decades, combined with modern technology and high-quality welding, resulted in final products meeting highest quality standards.

The corrugated walls are produced out of cold-rolled steel strips. The volume change of the transformer liquid caused by heating is compensated by the corrugated walls (in case of hermetically sealed transformer) or by the tank conservator mounted on the top (in the case of expansion tank transformers). Tanks are sealed with a steel sheet lid, either by bolting or by preparing the lids for welding, upon the customer's drawings.