Release time : 2015-06-12 11:06:15
SKF South Africa applied global and local bearing technology to design specific tooling to remanufacture three damaged large size spherical roller thrust bearings (SRTBs) at Komati Power Station in record time and at 45% less than the cost for new bearings.
When Komati Power Station found that replacement bearings would cost approximately R400k with an approximate two year lead time, they approached SKF distributor, Bearing Services Bethal (BSB) for assistance. BSB Manager, Lucky Houndalas, explains: "Determined to find a more cost-effective solution, we approached SKF's Remanufacturing team."
"General inspection revealed that the bearings were in a condition that required separation in order to get an analytical look at the running surfaces. Unfortunately we did not have the right technology to do so", comments SKF Bearing Remanufacturing Manager, Giscard Lailvaux. In fact, no such tooling existed in this country", continues Lailvaux. "But, one month earlier, while attending a management meeting on bearing remanufacturing in Steyr, Austria, I came across a tool used to separate these particular types of bearings and immediately realised that my team and I could locally custom-design and manufacture this tooling".
"We produced the tooling in record time, taking the first bearing smoothly apart in approximately 15 minutes, only to discover that it was irreparably damaged with excessive corrosion pitting on the outer ring thrust washer. This bearing was used as our test piece. Before opening the second bearing, we measured the bearing to ensure conformance to SKF geometric form tolerance and ISO specifications. Once measurements were satisfactory, we used the special tooling to strip the bearing. Then followed a detailed inspection of all components and, despite the deep-seated rust and water etching damage on the rolling element surfaces, this bearing was considered to be salvageable, and we continued with the remanufacturing process".
Lailvaux continues, "We documented all results and provided a detailed preliminary report. The conclusion was that remanufacturing would be possible on three of the bearings at 45% less than replacement costs and that the project would be completed over a brief 3-month period. Our next step was extensive polishing to remove rust, water etching as well as potential stress concentrations on the running surfaces of the bearing".
"After polishing all components, final inspection was done by representatives from Komati Power Stations and BSB before reassembly, who reported that the remanufactured bearing looked brand new and that SKF's quality of workmanship could not be faulted and we proceeded with reconditioning of the other two bearings", comments Lailvaux.
"The decision to remanufacture bearings is not made lightly as we must be confident that the remanufactured bearing will run problem-free during our customary six months warranty period", says Lailvaux and concludes, "We created customised solutions with the successfully design and manufacture of special tooling for local conditions and by sharing our engineering knowledge, we offered our customer a quick turn around time, kept their downtime to a minimum and passed on substantial savings".