Featuring an entirely new, patent pending design, a new Cat® dipper improves performance and reliability in hard digging applications of the Canadian oil sands without increasing demands on the hoist and crowd capabilities of the Cat 7495 HF Electric Rope Shovel. Improvements to shimming and inserts alone are projected to increase uptime as much as 0.25%, potentially leading to significant gains in production.
The new design optimises lip cutting angle, resulting in significantly reduced heel wear. Improving stiffness and dig performance, the ground engagement tools are pitched at an upward angle that results in less bending force and even tooth wear top to bottom.
Approximately 7% lighter than the current 45.9 m3 (60 yd3) latched dipper, the new design delivers more available cutting force for more consistent fill factors and increased production in difficult digging conditions. Using Finite Element Analysis (FEA) and virtual validation tools, engineers reduced the dipper’s weight, translating to lower stress on the machine, as well as longer life and improved reliability for key components of the shovel’s front end.
The dipper features a new vertical latch system that delivers improved system performance and lower part maintenance, reducing overall operating costs. Rather than sliding, the latch’s tapered-end design lifts the insert surfaces away from each other. The design extends wear life while reducing service time, contributing to improved uptime. The latchbar guide plate features a quick-change design, further reducing maintenance time and costs.
Optimised linkage on the new single wet-disk snubber reduces the rotational kinetic energy of the door by more than 40% on closing and 75% during opening, increasing service life.
Caterpillar engineers tested more than 300 dipper shapes and configurations in over 900 simulations using Cat proprietary software to analyse performance data, completing stress plots and wear plots for the models. The “virtual” machine, operator, and pile were all validated using actual machine data reviewed by Caterpillar subject matter experts for accuracy. The simulations showed that with the new dipper geometry, customers can achieve better penetration and fills per pass.
