OFR-97(2)-77 Development Of A Conveyor-Type Cross Pit Overburden And Material Handling System ? Revision 1, Appendix A ? Supplementary Overburden Crushing Info - User Experience With The Stamler Feeder/Breaker For Crushing Material Other Than Coal

Although the Stamler feeder/breaker has been used for coal crushing in underground mines for many years, it has only recently been applied to other crushing operations. Two companies presently using Stamler feeder/breakers for rock crushing were contacted regarding their experiences with the units in actual field use. In both cases information was obtained directly from the individuals responsible for field operation and maintenance of the units. White Pine Copper Co. has been using Stamler feeder/breakers for over two years to crush copper ore. They now have fourteen 450-ton-per-hour units on line. The ore has a compressive strength of from 18,000 to 28,000 psi and is extremely abrasive. Maintenance is performed on a tonnage basis. The breaker shaft is replaced every 250,000 tons (requiring about 4 hrs) and picks are replaced about every 1500 tons by the operator (requiring about 2 min per pick). Very little unscheduled maintenance has been required. Crushing costs are fairly high (estimated at 13 to 15t per ton including maintenance and operation) because of tale extreme abrasiveness of the material. A new Stamler feeder/breaker with Ultramet wear surfaces was put or line in June 1976. Ultramet was found to increase the life of belt transfer station surfaces by up to 400 percent and it is hoped that it will do the same for the feeder/breaker. At this time it is still too early to evaluate the performance of the Ultramet unit. If it does improve abrasion resistance, crushing costs could be greatly reduced. White Pine is very pleased with the units and the service provided by Stamler.