A Strategy for Reducing Costs and Improving Performance
BRENCO recommends a strategy that many shops have already adopted to optimize overall bearing performance and reduce both short term and long term costs. That strategy is to cannibalize the bearings returned from service, buying new components only to make use of any surplus of used components. (The most common situation is the use of new cone assemblies with surplus cups.) The shortfall in bearings available for return to service is made up by purchases of new, assembled bearings from a bearing manufacturer at OEM prices.
There are a number of advantages to this practice:
(1) New components typically are priced at a premium to the cost of an assembled bearing. Premiums on components customarily run in the range of 25%, depending on the manufacturer. Replacing scrapped components with assembled new bearings results in a cost savings of approximately 25%, and offers reduced shipping and handling costs.
(2) In order to repair six or more different brands of bearings currently in service on North American railroads, a shop must maintain a large inventory of new bearing components. The cannibalization practice would eliminate this substantial investment, replacing it with a small, low value inventory of surplus used components. This can have a significant impact on the operations return on investment.
While the cost savings are substantial, we believe the greatest benefits are realized in improved performance of the bearing fleet, as in the following advantages:
(3) Mixing new components, purchased at a premium, with service worn components in the same bearing assembly might make sense if the end user could be assured that all the components would last at least through the next wheel service life. But mileages between wheel work periods are increasing, especially with the trend to Class C wheels, and the bearing reconditioning standards permit return to service of certain acceptable defect levels. New components introduced into the used bearing assembly can be mixed with parts containing repaired and unrepaired spalls, diminished cone bore fit, water etching, and fragment indentions. Further deterioration of the used components can adversely effect any new components installed in the bearing, wasting the investment (at the 25% premium) in the new components.
Cannibalization of used bearings intuitively makes more sense, but hard data is also available to verify these conclusions. For example, a recent update of bearing related wheel removals by a midwest utility company showed that in their service, new bearings produced an average life of 352,000 miles and reconditioned bearings produced an average life of 168,000 miles. This study covered the time period of 1981 through 1987 and included wheelsets removed from service due to the following bearing Why Made Codes:
Code Description
04 Defective internal or external parts
50 Bearing overheated
93 Seals loose
97 Loose backing rings
99 Damaged seals
(4) With their more dependable service life, the new assembled bearings, purchased to make up the losses due to scrap, can be targeted to the high mileage, heavy load service applications. Unit coal train cars, container cars, and other intermodal cars are prime candidates for this approach.
(5) Finally, by utilizing cannibalization, the user can control his purchases of new product and continue to introduce into his fleet those bearing brands that have demonstrated the best performance, instead of merely perpetuating the composition of his existing fleet.
As both a bearing manufacturer and a major reconditioner of tapered roller bearings, BRENCO understands the advantages to the railroads of such a strategy. We have seen the scrap rates in our reconditioning shops and experienced the shortage of used bearings to replace the scrapped components. We have also seen our parts business increase dramatically in the past year. Spare parts sales is a profitable line of business for BRENCO, but purchasing replacement bearings, part by part, is not in the best economic or service performance interest of railroads and car owners.
Video Tapes Available
In effort to improve bearing performance in the field, BRENCO has produced several video tapes which are available to you upon request. The videos available are in VHS format. They are:
- Brenco -- Performance That Counts
- Bearing Retention
- Proper Bearing Mounting Procedures
At BRENCO, we continually strive to provide educational and support materials that our customers may find useful. If you have recommendations for literature or future video tapes, or would like to order the video tapes mentioned above, please call or write to the address below.
The Technical Forum is an information resource for the rail industry and is provided as a courtesy of Amsted Rail Group. Suggestions, inquiries or comments are welcomed and should be directed to:
Editor, Technical Forum
BRENCO, Incorporated
P.O. Box 389
Petersburg, Virginia 23804
804-863-1713
Additional copies provided upon request.
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