Converting grease lubricated gear spindles to Mobil SHC™ 639 synthetic oil lubrication helped improve equipment life span by 250%

Situation

A hot rolling mill uses gear spindles that transmit high torque between its gearboxes and rolls. Traditionally, gear spindles are grease lubricated. Under severe operation conditions, grease has a tendency to bleed more oil and remove grease from the contact zone. Insufficient lubrication increases tooth wear and keeps wear particles and contamination in the contact zone. Service life of the grease-lubricated spindles had been about 9 months.

Recommendation

An ExxonMobil engineer worked closely with the equipment builder, SMS Siemag, to convert the gear spindles to oil lubrication. Mobil SHC™ 639 synthetic circulating oil, with its high, 1,000 cSt viscosity, was selected due to its ability to withstand the high shock loads experienced even in normal operating conditions.

Result

By converting grease lubrication of the spindles to oil lubrication with Mobil SHC™ 639 circulating oil, the lifespan of the spindles increased by 250%. Customer has not experienced any failures in 32 months^* and continues running the mill safely without unplanned spindle maintenance.

*This proof of performance is based on the experience of a single customer. Actual results can vary depending upon the type of equipment used and its maintenance, operating conditions and environment, and any prior lubricant used.