Reliability of Cooling Tower Drives: Improving Efficiency with New Motor Technology

Cooling towers are used in many process applications in the petrochemical industry, so reliability of these towers is crucial. In many cases, redundant towers need to be installed to ensure that a process will not have to be stopped due to a cooling tower failure. The most prevalent cause of cooling tower downtime is failure of the right-angle gearbox or associated mechanical components, such as the driveshaft or disc couplings. The elimination of these components can reduce the losses in the drive system and offer the possibility for improved overall system efficiency. This article describes new developments in motor technology that allow for the replacement of high-speed motors, driveshafts, couplings, and gearboxes with a slow-speed permanent magnet (PM) motor. A case study is presented with provisions of maintenance and efficiency improvement data.