New tertiary cone crushing circuit delivers more finished product & less recirculation load
Maintaining optimum yield from any cone crushing circuit is ultimately achieved by combining the latest cone crushing technology with solid application expertise and highly-responsive equipment lifecycle management. The latter is essential when fine-tuning a crushing circuit for peak performance – and it’s best driven by an ongoing producer/equipment manufacturer “partnership” that ensures the highest production capacities and the lowest percentage of recirculating loads.
Circuits with high recirculating loads eat up more capacity and horsepower in the crusher, while also increasing wear – and unnecessary recirculating loads send saleable material back to the crusher rather than to the finished product stockpile.
Minimizing recirculating loads is an imperative for producers such as the RiverStone Group, which operates 15 active quarries throughout Iowa and Illinois. As a family-owned business since the late 19th century, the company “prides itself on pushing the envelope in productivity and innovation.” RiverStone is known for its abundance of Class A-Quality stone products which meet stringent DOT and FAA quality assurance standards.
At its Colona, Illinois-based Cleveland Quarry, the company recently upgraded its plant with higher-capacity primary and secondary crushers. For optimum yield of finished product at its tertiary circuit, they installed a new P500HD Patriot® Cone Crusher manufactured by Superior Industries. The result is greater plant uptime, long-term efficiency, reduced wear costs, minimal recirculation load, and increased production capacities at lower costs per ton. Delivering a speedy return on investment, the site has nearly doubled its tons-per-hour output since the installation of the new crushers.
Cleveland Quarry Plant Superintendent, Scott Skerston, recently calculated the circulating load ratios of the new Patriot® Cone Crusher. He reports that at a closed-side setting of 1-inch, the cone processes finished product at a 78-percent throughput; and at a ½-inch closed-side setting, the throughput percentage reaches a high of 83-percent.
“We’re getting maximum efficiency, and very little recirculating load, while averaging 80-percent of our crushed material going directly out to the finished, saleable product stockpile,” says Skerston. In part, he attributes this to the cone’s spiral tooth bevel gearing system, which “engages more gradually, giving an efficient transfer of horsepower to the rock, rather than to the structure of the machine,” he says.
As a result, the cone is proven to perform at higher speeds with less noise and vibration. “With its uptime and availability at more than 97-percent, the Patriot Cone maximizes our production of A-Quality concrete stone and asphalt chips. Before we added all the new crushers, we ran at just over 400-tons per hour. Now we’re running steady at 800-tons per hour due to our crushing advancements,” adds Skerston.
Next-level crusher technology
Skerston says that the design improvements on the Patriot® Cone Crusher make it far more durable, reliable and user-friendly than older-style cones. Unlike most crusher models, he says, the Patriot® Cone Crusher’s counter-shaft spins in a counterclockwise rotation, which causes the crusher to open if clamping pressure is lost, reducing the risk of catastrophic failure.
“This feature literally saved us last production season when a simple solenoid valve failed and would not reset the clamp pressure. The counterclockwise rotation allowed the cone to open, preventing any damage to internal components. When older-style cones lose clamp pressure, the bowl tightens down, often snapping the shaft and leading to machine failure,” he adds.
Another feature that prevents costly damage to the new cone’s crushing chamber is a unique tramp relief system. “First, it’s designed with fewer accumulators for minimized maintenance, but most important is the inclusion of a secondary pressure relief valve that ensures the crusher will open if a tramp event occurs,” says Michael Schultz, crushing product manager for Superior Industries. “This means that even if an accumulator fails, the secondary relief valve will provide immediate pressure relief, allowing the crusher to open,” he explains. Additionally, he points to an inverted design of the tramp release cylinders where the hydraulic cylinder rod seal is not exposed during operation, greatly reducing the potential of contamination and failure.
Schultz adds that the Patriot® Cone Crusher is more robust than the typical cone, as “it’s beefed up to increase the strength of the unit with a heavier-duty adjustment ring, base frame, eccentric and clamp ring, and bowl castings. We’ve made sure it will withstand the toughest applications,” he says.
An in-house cone crusher automation package (Vantage® Automation), says Schultz, is the latest addition to the Patriot Series. “It’s completely built in-house by the Superior Industries team with no third parties involved, allowing one-call service and support; and offering a complete automation package that is far more affordable than competitive systems,” he says.
Vantage Automation monitors all the vital functions of the crusher. “Operators can track or trend about anything they can think of,” says Schultz
“An automation package should be simple and easy to use. Importantly, it acts as a warning system that alerts operators to conditions such as bowl float, excessive amperage or temperatures, and lubrication or low-flow oil issues,” says Schultz, who brings more than two decades of crushing industry experience to the Superior Industries team of crushing application engineers and service technicians. “Our mission is sharing hands-on expertise and partnering with producers throughout the lifecycle of the plant and its components,” he says.
Expertise & equipment lifecycle management
As the RiverStone Group upgraded its crushing circuits, Skerston worked closely with Chris Wade, a customer service and technical support technician for Superior Industries, which operates a 70,000-square-foot crushing equipment and parts distribution center in Pekin, Illinois. “Chris, along with the service and parts support team, have specialized in cone crushing for many years. They know how to analyze our application to make us more efficient,” says Skerston. “It’s such an advantage to rely upon the knowledge of the equipment manufacturer. The product and parts support is excellent, and the Patriot Cone does just what it’s designed to do,” he says.