Novelis placed an order with the SMS group for the supply of four spare gear boxes for two Tandem Cold Mills. These are spur pinion gear units, in which the two gear unit types, spur gear unit and pinion gear, are combined in one housing. The challenge was not only to complete them within a delivery time of 12 months, but also to adapt them specifically for the two locations of use in South Korea and Brazil.
The specification was that the existing interfaces to the foundations, the transfer points to the central lubrication system and the electrical connections of the temperature sensors and the extension to vibration sensors should continue to be used for Genius CM® . This was a prerequisite for a 1:1 replacement of the existing gearboxes with the new ones without any problems and without long downtimes.
During the project phase, there was regular and close contact with Novelis in order to work out the drive concept with the customer. The greatest advantage of the new gear sets is that up to 30% higher torques can be transmitted with the same external dimensions. This is a result of the double-helical design of the drive stages and the application of SMS group's Advanced Gear Design. Here, tooth profile and flank profile are calculated individually which results in a uniform pressure distribution over the entire load flank. The maximum contact pressure is much lower than the pressure on the standard tooth. Furthermore, optimized housings with higher rigidity and an improved bearing and housing screw design ensure reduced vibrations, which leads to an improvement in the overall performance of the gear unit and the plant.
