Coils of steel are placed on winders and then are drawn into a state of the art CNC turret punch which follows a computer driven pattern ensuring the uniformity of all holes (for bolts) punched into the steel. These holes are “punched” into flat sheets of steel taking into account the fact that the width of these flat sheets of steel will be reduced by a ¼ of their current size once they enter the corrugating machinery. All holes, slots, or any penetration into the steel used in Steel Core tanks are always clean and uniform guaranteeing they will line up in the field every time.
The pre-punched steel sheets are then taken to the corrugation line. We have developed a “tension reduction system” that allows the steel to remain supple when drawn into the corrugator. Corrugation begins in the center of each panel, utilizing two dies or wheels, and expands outward by adding successive dies as the steel is drawn further through the machine. Center line corrugation and our tension reduction system ensure uniformity and maximum strength for each panel.
The curvature of each piece of steel is then applied by running the steel through a bender at the end of the line. Curvature varies depending upon the circumference of a tank.
Utilizing these processes we end up with uniform “panels” with consistent corrugation, curvature, and penetrations on every piece, along with quality control checks being made every 20th panel.