Prescreening optimizes the crushing process
With the new equipment, Riverbend was averaging 305 to 335 tph, depending on the feed. “If the feed is a good, well-blasted material, with this closed-circuit arrangement I can easily put up to 340 tph through. “By well-blasted, I mean a rock that’s not chunky, that’s shot well throughout with some fines in it and a variety of sizes that go into the primary. The moving jaw on the jaw crusher is much longer than the fixed jaw,” said Duff Boyd, President, Riverbend Construction Services. “That longer crusher jaw not only protects the pitman on the jaw crusher, which is great, but secondarily, it eliminates the edge or lip found on competing crushers, with their shorter crusher jaws – a place that bigger rocks tend to catch and hang on to. KLEEMANN’s taller crusher jaw all but eliminates stoppage due to big rocks. If you are doing 330 tph, and you have to stop for a half hour to dig the rock out, you’ve lost 165 tons of productivity.” Instead of a grizzly, Boyd’s new MC 110 Zi EVO primary jaw crusher utilizes an independent prescreen that speeds productivity. “The prescreen pulls all the fines out, and that’s where the tons per hour really pick up,” Boyd said. “But if it’s a coarse material, it all has to go through the jaw and my tons per hour will go down. The prescreen is the ticket. It cuts down on the wear on the crusher jaws and the wear plates. It prevents wear and tear, and increases throughput.”