Scheduled for completion in July 2016, U.S. Bank Stadium, the new home of the Minnesota Vikings, is a fixed roof structure that will be nearly 30 stories tall at its highest point. During construction, the base plates of some of the structural support columns needed to be pre-heated to 400o prior to welding. Traditional heating by flame proved to be difficult. It was determined that induction heating was the right solution to safely and efficiently heat the steel to an exact temperature. Induction heating is the preferred method to address challenges associated with the pre-heating of structural steel because it provides a safe and accurate method of heating the metal to a precise temperature.
Red-D-Arc offers Miller ProHeat 35 Induction Heating Systems (IHS) available for rent, lease and sale. This highly efficient technology uses non-contact heating to induce heat electromagnetically rather than using a heating element in contact with the part.
UPDATE: This project was completed ahead of schedule.
A customer involved in the rebuilding of a hydroelectric power generation station came to Red-D-Arc with a unique challenge: Use induction heat to help separate a massive rotor from its center shaft assembly. A traditional approach is to use a combination of open flame along with dry ice which would have taken several weeks to set up and also ran the risk of being ineffective due to the scale and complexity of the project.
Sil Nonis, an induction heating specialist at Red-D-Arc, suggested using 6 induction heating units activated in sequence to provide thermal growth in a uniform pattern; releasing the interference from the center shaft before lifting the rotor. The 6 Miller ProHeat 35 Induction Heating Systems powered two half circle assemblies, positioned at the bottom of the locking ring which was 5′ in diameter as well as two half circle assemblies positioned on a top locking ring which was 4′ in diameter. Massive rotor arms also had 4 pads attached to them, positioned in sequence.
Setup took approximately 2 days and removal of the rotor was completed in a single day. The same process will be used to reinstall the rotor after it has been rebuilt. Over the next few years two additional rotor assemblies will be removed, rebuilt and reinstalled using the same process.