Caterpillar has introduced a new wet disk snubber upgrade for dipper doors on its 7495 series electric rope shovels, built specifically for removing large amounts of overburden and ore at a reduced cost per tonne.
The oil-filled snubber is maintenance and adjustment free for its 12,000-hour life before rebuild, which aligns with dipper service life.
The snubber plays a critical role in truck loading as it provides controlled resistance to the motion of the dipper door. During opening, the damping torque slows door velocity to prevent collisions with the truck body. During closing, the damping torque prevents the door from slamming against the dipper body and dipper structure.
The new snubber design, a sealed, oil-immersed clutch pack, eliminates a daily maintenance touchpoint and aims to deliver much longer life than the standard snubber. Additionally, the wet disk snubber can be rebuilt three times before replacement is needed, and rebuilds are simpler and faster than standard snubber rebuilds.
This helps to reduce maintenance time and costs, improve reliability, enhance safety and lower total cost of ownership. In field validation at a coal mine in Wyoming, United States, wet disk snubbers also reduced frequency of repairs to the dipper door and latch keeper.
The wet disk snubber is retrofittable and available for both latched and LatchFree Cat dippers installed on Cat 7495, 7495 HF and 7495 HD Electric Rope Shovels. The snubber upgrade can be retrofit in about two days and is typically completed when the dipper is being rebuilt.