Company Announcement - Designed and built to strict Caterpillar specifications, Cat wheel rims help ensure better drive train performance and extended component life in off-highway trucks by combining the highest level of strength with the minimum amount of weight to maximise payload and decrease fuel costs. “By functioning as an integral part of Cat drive train systems, these rims help extend the life of all power transmitting components, as well as the suspension, bearings, brakes and tyres,” explains Barloworld Equipment senior product manager, Wally Parsons. “This is why tyre selection and fitment is such an important part of the overall production planning on any mine.” (Barloworld Equipment is Caterpillar’s southern African dealer.)

Tyre removal and installation is a specialised area. It can also be a time consuming exercise when using standard rim configurations. Traditionally the only way to change the rear axle inside tyres on a mining truck has been to remove the entire outside tyre and associated rim systems. On average, this process takes between six and seven hours to complete by a well-trained team.

Caterpillar’s Quick Change Rim system has revolutionised this practice and greatly contributed to improved production efficiencies by reducing change-out times to around two hours, due to fewer rim base removal and installation procedures. As a result, the system is proving particularly popular with large and ultra size mining truck fleet owners. Key models using QCRs include the Cat 785C, Cat 785D, Cat 789D, Cat 793D and F, Cat 795F, as well as the range topping Cat 797F. The QCR system has a position specific outer rear rim with separate dual bead seat bands and flanges. These components allow the tyre and rim components from the inner rear rim to slide over the outer rear rim. The key factor here is that the system allows the inner and outer tyres to be removed and replaced without having to remove the rear axle outside rims.

The back section of the QCR base is modified to include additional lock ring and O-ring grooves for a second bead seat band, which allows the tyre to be removed without the need for a hydraulic bead breaker tool to separate the inner tyre bead from the rim base.

“The lock ring is a single piece design,” explains Parsons. “It’s made with specially designed materials that allow it to be expanded for easier attachment and removal. Compared with other aftermarket quick change rim systems, it’s the only one that is interchangeable between all six tyre positions.”

The wedge shape of the flanges, bead seat bands and lock rings increase friction and torque, which helps keep the tyre in place to prevent tyre slip in high rim pull and heavy retarding applications.

“Quick change rims also encourage more frequent and effective tyre rotations and inspections, which in turn improves overall life,” adds Parsons.