Bearings for sour gas application
SKF retrofits compressor to save refinery €15 000 000
A Canadian oil sand refinery was experiencing frequent bearing failures in an oil-flooded screw compressor. The unit handled the vacuum-off gas from a very large vacuum tower in a process designed to avoid flaring of sour gas (H2S), which was present in concentrations of 30-40%.
Along with exposure to harsh gases, the production-critical compressor had to endure continuous operation. And with no back-up unit online, the MTBF rate it was experiencing – less than six months – was unacceptable.
The SKF solution
SKF worked with the refinery to engineer a custom bearing solution consisting of high-nitrogen, stainless steel rings, ceramic rolling elements, and machined brass cages. SKF then helped the refinery’s maintenance team install the bearings in the compressor.
The SKF engineered bearing solution has so far reportedly multiplied the service life of the compressor six-fold, extending MTBF from 3,800 hours to more than 23,000 hours.
This service life extension increased the reliability and availability of the refining process, significantly reducing sulphur dioxide (SO2) emissions caused by flaring. Currently the unit is still in service, and the refinery reports that the overall financial benefit from the extended service life is in excess of €15 million!