For a major North American copper producer, its Haver & Boecker Niagara SAG mill vibrating screen is the heart of its processing operation and is built to endure the mining industry’s tough working conditions. The site operates 24 hours a day, processing more than 2,000 t/h, 365 days a year, so superintendents expect wear and tear. Haver & Boecker Niagara comments: “They rely heavily on the equipment and expect the machines to produce a clean, properly-sized product every time. But, like any piece of equipment, a vibrating screen eventually wears down, and the most strategic, long-term solution isn’t always purchasing new. In this producer’s case, a refurbishment offered a way to bring life back into a well-used machine for less than the cost of buying new.”
The mine specialises in the production of copper concentrates with gold and silver credits; the operation’s heartbeat comes from a Haver & Boecker Niagara XL-Class vibrating screen. As a vital piece of equipment in the operation, the XL-Class sizes more than 30 Mt of copper ore per year, at 92% mechanical availability, which includes pre-scheduled downtime for equipment maintenance. The mine’s 3,600- by-8,500 mm (12- by 28-ft) XL-Class is Haver & Boecker Niagara’s largest single-deck machine in North America.
The vibrating screen offers an impressive 31 square metre (336 square foot) screening surface. “Beyond size, the vibrating screen’s design is simple, featuring a bridge-mounted exciter drive system — the other key factor that appealed to the operation. Its construction is straightforward, featuring crossbeams, rails, side plates and a bridge, simplifying maintenance.” The producer has one XL-Class working within its operation, and a second machine ready to move into place when maintenance is required.
No time for downtime
After years of hard work, the XL-Class began to show wear. The producer pulled the first unit from operation, moved their backup XL-Class into place, and called Haver & Boecker Niagara’s service technicians to evaluate the equipment, and determine whether it was time to buy new or if they could refurbish the existing machine. “Onsite service calls allow our technicians to examine the entire screening application from start to finish,” said Markus Kopper, General Manager of Haver & Boecker Niagara’s Rocky Mountains operation. “Visiting the facility and examining the entire screening operation offers us insight into how the customer’s operation works and what we can do to help them achieve maximum uptime and profits.”
The technicians used Pulse vibration analysis and developed a strategic plan after inspecting all critical components and determining what needed replacing or rebuilding. “We like to start each refurbishment as an open discussion, sitting down as a team to consider the efficiency of the equipment and adjustments to improve that efficiency. Every decision involves the customer and their feedback and experience,” Kopper said.
After examining the vibration analysis reports, inspecting the equipment and observing the overall operation with input from the customer, the decision was made to refurbish. It was a decision that would provide the operation with a machine that will run like new, but for about a quarter of the cost of buying a new vibrating screen.
The producer approved the proposal, which included onsite installation of new or re-engineered parts to improve the screen’s performance. These upgrades ensured the vibrating screen would run 24 hours per day between scheduled maintenance intervals. During the refurbishment, the backup XL-Class moved back into the heart of the operation. When the three-month refurbishment process ended, Haver & Boecker Niagara again tested the equipment with Pulse to ensure the machine’s speed, stroke and orbit.
“The copper producer was beyond impressed with the service they received. Management expressed that having the rebuild completed onsite was comforting because they saw the process from start to finish — something they say they don’t get from just any manufacturer. Additionally, the process resulted in zero downtime.”
And the screen OEM says its service capability doesn’t stop at its own models of screens. “No matter the brand of vibrating screen or screen media, our technicians can work with it to help an operation reach peak productivity,” said Kopper.