Portables in the Quarry
Whether it’s a screening plant or a crushing plant, portable plants have carved their way into our quarries.
By Kerry Clines, Senior Editor
Portable crushing plants are now able to handle larger sized rock, making it possible to use only portable crushers throughout an entire operation.
Grasan custom-designed a 3,000-ton-per-hour, tracked, horizontal impactor plant that features a New Holland-type Williams three-blow-bar impact crusher with a Williams 6-foot by 50-foot apron feeder and Simplicity 7-foot by 20-foot grizzly bar scalping screen that handles material up to 60 inches in size. The KRHT-60E measures 47 feet high, 39 feet wide, and 122 feet long, and weighs 1.2 million pounds. The 120-ton hopper is 24 feet wide, 29 feet long, and 9½ feet high. A built-on BTI hydraulic hammer breaks up oversize materials. The chassis mounting consists of two pairs of custom-designed B9 tracks with 40-inch-wide smooth pads and self-leveling stabilizer legs. The twin-track unit is powered by two 300-horsepower electric motors, travels at 0.5 miles per hour, and can turn at various angles up to 90 degrees.
The new MR 110 Z EVO unit from Kleemann features a new material flow concept — the discharge chute under the crusher is 4 inches wider than the inner width of the crusher, and the discharge belt is 4 inches wider than the discharge chute. Rapid flow of the material keeps it away from the critical area under the crusher and reduces wear. An independent vibrating double-decker pre-screen is said to improve cost efficiency. A newly designed crusher bypass includes changes to its geometry and form to boost performance and reduce wear. Optional new and improved screening units are available and are more than 44 percent larger in size than those on previous units, allowing for tonnages of between 350 and 450 tons per hour.
Atlas Copco’s new line of Powercrusher track-mounted mobile crushers and screeners includes jaw crushers, impact crushers, and cone crushers with a crushing capacity from 242 to 606 tons per hour, and screeners with a capacity of 242 to 485 tons per hour. The four jaw crushers incorporate “Quattro Movement” made possible by an up-thrust toggle plate position. This causes a figure-eight motion in the moving jaw, which increases the feeding capacity and produces a post-crush at the crusher outlet. The six impact crusher models use optimized geometry in the crusher box with hydraulically adjustable swing beams, resulting in a minimal percentage of oversized material and high reduction ratios and throughputs.
McCloskey’s new J-40 compact, track-mounted jaw crusher features a true 24- by 40-inch jaw. Additional features include push-button, closed-side setting control; an ultrasonic level sensor in the jaw to automatically adjust feed rate; and a 7.4-cubic-yard hopper capacity. Transport dimensions are 8 feet, 3 inches wide; 41 feet, 7 inches long; and 10 feet, 6 inches high; with a weight of 68,500 pounds. Power requirements are supplied by a 225-horsepower Cat C6.6 ACERT engine driving a high-efficiency hydraulic system.
Kleemann’s MC 110 Z track-mounted jaw crusher boasts a high-torque reversible hydraulic jaw and fully hydraulic gap adjustment. The R version has an integrated grizzly, while the Z version has a fully independent, double-deck pre-screen. The unit can be fitted with an optional final screen and oversize discharge, which allows the operator to produce a final graded product with a single machine. The fuel-efficient crusher uses a Cat C9 engine and is configured for operation by a single person who can feed raw material into the crusher while using a wireless remote-control unit in the cab of an excavator or loader. Crusher transport weight is 99,200 pounds; length is 47 feet, 5 inches; and width is 9 feet, 10 inches.
FLSmidth’s wheel-mounted XL300 and XL400 cone crusher plant options include rear discharge and rear-feed side discharge. Both crushers can be configured with two- or three-deck horizontal screens that are 6, 7, or 8 feet by 20 feet, which provide open-circuit crushing and screening. Hydraulic run-on jacks are available as an option to level the plant after it is pulled on site. A high pivot point and large crushing stroke offer better crushing action throughout the crushing chamber. An active feed opening creates better end-product shape. The crushers also employ “fail safe” hydraulics through an internal relief valve within the dual-acting tramp release cylinders.