Thu December 17, 2020
Drawing from more than a century of rope shovel innovation, the 2021 Cat 7495 and 7495 HF electric rope shovels (ERS) combine multiple standard feature upgrades that increase operating efficiency up to 10 percent to improve machine productivity. Component enhancements, increased frame durability and improved serviceability help reduce cost per ton of material moved by as much as 15 percent, according to the manufacturer.
"Consistently, our customers tell us machine availability and productivity are primary contributors to their operation's success. From the full adaptive control system for HydraCrowd to more innovative technology and data security, the advances made to the 2021 electric rope shovels reflect our commitment to meeting their needs," said Dan Wyatt, ERS product value stream manager.
"Many of these improvements are compatible with shovels in the field, so customers can realize these gains through upgrades to their existing fleets as well as new machine purchases."
A new propel gear case for the 7495 and 7495 HF models nearly doubles the life of propel gear cases in some extreme operating conditions. Precise adjustments to gearing geometry and advancements in tooth hardening enhance gear case durability and productivity. The result is lower total cost of ownership as much as $8 per hour when the drive system is replaced at one scheduled time, according to the manufacturer.
Additionally, an ecology drain simplifies oil draining and enables kidney-loop flushing, which reduces abrasion-causing contaminants and oil change frequency.
Updates to the 7495 AC electric drive system deliver greater reliability, improved maintenance access, enhanced safety and expanded high-altitude and temperature capabilities. A liquid-cooled motion regulator cabinet efficiently dissipates heat generated by electrical components and enables operation at -40 F (-40 C) to 122 F (50 C) and altitudes as high as 17,220 ft. (5,250 m) without derating. A faster propel transfer switch cuts lag time by 75 precent to improve productivity, while common motors in multiple applications means fewer parts to stock, improved parts availability and simplified maintenance.
Slashing maintenance time by days while enhancing safety, reconfiguration of the crawler carriage allows drive shaft and tumbler replacement from the outboard side without removing the propel transmission. With this design, thrust loads are evenly distributed on large, tapered roller bearings rather than bronze thrust plates, increasing durability to align with 25,000-hour planned rebuilds, even in harsh environments, according to the manufacturer.
Structural Improvements Boost Longevity
Stress from every load passes through the swing rack. An enhanced design includes a single-piece rail casting that eliminates vertical segment cracks to increase durability. The rail provides a uniform path for roller movement, preventing rollers from coming loose and creating irregular wear patterns. The upgraded third rail improves access for inspection and retightening plus added support to the thrust rail during operation. New swing girder bushings and girder-to-chassis shim designs offer improved access, reducing service time.
All major rope shovel structures are built with high-strength steel and rugged castings, joined and thermally stress relieved to deliver reliable operation in harsh mining conditions. Full penetration, profiled and ground welds are made at critical junctures, and MT, UT and X-ray inspections ensure weld quality. Structures are stress-relieved to prevent cracking, and white painted interiors facilitate inspection.
Both the 7495 and 7495 HF ERS models now offer a full Cat bill of materials, streamlining the parts ordering process and improving parts availability.
Technology Increases Efficiency
Both the 7495 and 7495 HF come standard with Product Link Elite, which transmits critical machine operating data such as utilization, location and condition via cellular or site internet connection. Added router functionality helps to protect data security.
Advanced productivity tools within Product Link Elite enable a cycle segmentation algorithm, and the combined data allows for advanced analysis of productivity.
When linked with the available Cat MineStar Fleet, real-time machine tracking produces a comprehensive overview of all equipment assets to assist with fleet management and productivity. Providing real-time feedback to improve loading efficiency, available MineStar Terrain uses guidance technology and an in-cab display to deliver precise dipper position guidance. Optional MineStar Health delivers critical event-based machine condition and operating data, while its advanced diagnostic and analytic tools improve service efficiency.
The standard Operator Assist – Enhanced Motion Control simplifies machine operation to promote high production while protecting the machine. This system is designed to yield more reliable crowd rope replacement schedules, full design life for hoist ropes, reduced wear on crowd brakes and longer life for hoist gear case components.
HydraCrowd Full Adaptive Control
A final piece of a multiphase enhancement initiative for HydraCrowd, a new adaptive control system (ACS) delivers up to 25 percent cost savings on the ACS valve, resulting in up to 5 percent total cost of ownership savings for the entire system. Lower initial costs, rebuildable elements and improved accessibility combine to reduce the time required for replacements. The new design increases reliability without significantly changing the HydraCrowd maintenance schedule.
The new circulation filter employs two smaller, easily accessed filters that do not require roof panel removal for replacement. More affordable than the previous single-filter design, the new configuration also reduces replacement time, according to the manufacturer.
A new filter placed at the pump drive transmission improves filtration of the lubrication fluid, helping to extend the life and reliability of the system by reducing contaminants and decreasing wear. The new pump drive transmission filter assists in reducing unplanned maintenance events to decrease downtime.
For more information, visit www.cat.com/mining.