The technology includes the latest in electrical grounding capabilities and is designed to extend bearing life and reduce operating costs for motors driven by Variable Frequency Drives (VFDs). Although VFDs have recently become more popular because of their ability to deliver greater system efficiency and extend motor life, they can cause problems.
This is because VFDs operate by delivering power to the motor in a series of positive and negative pulses, which often results in unbalanced voltage that can accumulate in the motor shaft until it can find a path to ground. Without proper grounding between the shaft and the motor housing, the bearings often become the path to ground. The resulting electrical discharge can drastically damage or even destroy the bearings in just a few months of service.
Flowserve’s Bearing Gard technology has integrated electrical grounding protection in place, ensuring substantial elimination of shaft voltage, which helps to significantly extend bearing life. It also increases electric motor reliability by guarding against the two main causes for premature motor failure, which are bearing contamination and damage due to electrical discharge.