Digging for the Right Defect Repair
In the mining industry, replacement parts and components for industrial equipment are typically not on hand, or readily available due to their size, cost and lead time. So, operators need a timely process to fix their components in-house or risk incurring additional costs due to lost hours and extended downtime.
This was the case for one Cleveland, Ohio based gearing manufacturer, when a repair was needed on the pinion gear of a dragline excavator. The pinion gear is part of an entire gear train assembly, and if they are not maintained regularly, lubricant can leak from the seal causing the bearing to seize and gall to the shaft. When this happened, Horsburgh & Scott Co. were tasked for getting the gear and ultimately the crane back in working order.
When the seized bearing was removed, excess material from the journal was also removed, resulting in a gouge to the surface finish.
Traditional repair techniques such as welding, sleeving and metal spray can take up to four to six weeks due to the disassembly and shipping time, resulting in extended downtime, as well as being costly.
The bearing in question had incurred a gouge measuring 0.030” in depth, 0.75” wide and 12” long, making it 0.012” undersize. When using selective plating, defects are typically repaired with one or more layers of copper, and then covered with a wear resistant deposit that has good release or wetting characteristics. In this instance, the bearing journal was first plated with 0.001” thickness of copper and then masked for the defect repair. The anode that was used to fill the defect, covered the full length of the gouge which was filled with three layers of copper and hand-finished in between. The final layer was dressed flush then plated with 0.006” thickness of nickel using an ID plater.
By using the SIFCO Process®, Horsburgh and Scott Co. was not only able to return the crane to service with minimal downtime, but was also able to improve the time between failure rates and saved significant costs compared to the alternative repair methods.
The SIFCO Process® can be used in other areas of the mining industry including:
OFF HIGHWAY VEHICLES (OHV)
- Wheel hubs
- Differential housings
- Section head housings
- Hydraulic pump housings
For more information on the SIFCO Process®, contact firstname.lastname@example.org or call us at 800-765-4131.