Progress within the process

At the West Nyack quarry, the first three crushing stages are open circuit. The primary gyratory crushes the stone to 8-inch minus and sends it to a surge pile. At the secondary stage, the 7-foot cone crusher reduces material, and it is screened to 1-1/4-inch minus and 1-1/4 inch by -1/2 inch. The 5-foot cone crushes the oversized material and sends it to a three-deck screen that sizes it to 3/4 inch, 5/8 inch, and 3/8 inch. The quaternary stage is closed circuit, where the two Raptor XL400s are set at a 1/2-inch closed-side setting.

Hardick says the two Raptor XL400 cones can each produce at 750 tons per hour, which allows the company to send stone to one or both cone crushers, depending on production needs. “Anything over 750 tons per hour, and we have to split the production between them,” he adds.

“The science of breaking rock hasn’t really changed in recent years,” Bulnes says.  “Mechanically, equipment is pretty much the same. But it’s how you optimize and manage your equipment, make use of automation, and interface with computers that help to improve the equipment’s performance. For instance, we can control both Raptor crushers with one computer program and one screen, which is a big improvement over our other setup where we had to go back and forth between two computer programs.”

“Being able to set the size on one screen in the control room helps us to fine-tune the process, which raises our quality,” DeAngelis says, adding that he also appreciates the cones’ ease of maintenance. “The controller tells us how much the liners have worn, so it’s easier to schedule liner changes. And there are very few moving parts, so they are easy to work on,” he continues. “We’ve enjoyed a lot longer uptime with these machines than with crushers we’ve used in the past. That makes it easier for us to produce the stone we need to match our sales.”

Hardick agrees. “The Raptors (cones) are awesome,” he says. “The controller package allows us to adjust them automatically. And if we keep the (fluid) levels correct, and change the oil on schedule, they’re practically maintenance free. We typically go 400,000 tons before we need to make a liner change.”

“Now, until we get the FLSmidth gyratory into production, the bottleneck is at the current primary,” Bulnes says. He estimates at the upgraded production rate, the West Nyack property will still have approximately 35 to 40 years of material reserves.

Extra efforts yield community benefits

The West Nyack Quarry essentially runs year-round, only shutting down for six weeks in January and February for maintenance, repairs, and crusher rebuilds. According to Charlie Beers, the operation’s pit manager, “We blast just one or two times per week at noon. We blast bigger shots this way, but we’ve found that for neighbor relations, it’s better to shoot more material less often. We also have started to drill and blast down in the west side of the pit.  It’s deeper in the hole, so it’s quieter,” he adds.