Caterpillar updates drive system for electric rope shovels

Caterpillar has updated the AC electric drive system for Cat 7495 and 7495 HF electric rope shovels to deliver greater reliability, improved maintenance access, enhanced safety and expanded ability to perform at high altitudes and in extreme temperatures
Caterpillar updates drive system for electric rope shovels Caterpillar updates drive system for electric rope shovels Caterpillar updates drive system for electric rope shovels Caterpillar updates drive system for electric rope shovels Caterpillar updates drive system for electric rope shovels

A Cat 7495 electric rope shovel loads a Cat 797F truck in demonstration

Staff reporter

The company stated that the updated system also is designed to easily integrate with advanced technologies.

Dale Blyth, product manager, electric rope shovels at Caterpillar, said: "Caterpillar and our predecessor in shovel design and manufacturing, Bucyrus, have supplied more than 300 AC electric rope shovels. The most recent advances in AC drives are integrated in this update and demonstrate how we apply our experience to help customers lower cost per tonne and bolster safety."

Updates include a liquid-cooled motion regulator cabinet for more efficient dissipation of heat generated by electrical components. The new system is designed to enable shovels to operate at temperatures of -40°C to +50°C and altitudes of 5,250m without derating. The system can also eliminates airborne contaminants in the cabinet and lengthens service intervals for reduced costs and greater uptime. Additionally, a new, faster propel transfer switch cuts lag time by 75% for improved productivity.

New technologies enable consolidating two cabinets in the machinery house to create space for easier maintenance access. The updated maintenance station is designed for integration of current and future technology solutions, including Cat MineStar.

The drive system design uses common motors in multiple applications, which means fewer parts to stock, improved parts availability and simplified maintenance. The new motors have higher power densities, smaller frame sizes and optimised footprint, which aids access.

The Cat rope shovel electric drive system still features elements such as fuseless insulated-gate bipolar transistor (IGBT) modules. In addition, the on-board maintenance station still aids technicians in identifying faults and resolving issues.

The new electric drive system will be on all new production 7495 and 7495 HF shovels beginning in late 2020. The system is not intended for retrofit, though some elements, such as the fast propel transfer switch, are available as upgrades to machines already in service.