Casting Study: Low-Speed, High-Load Bearings

The Champion Series IV grader incorporates ZA-12 alloy low-speed, high load bearing to improve operation performance. Front Axle Bearings — This bearing application materialised as a replacement for the grader’s front axle needle bearings. The needle bearings performed well when conscientiously lubricated but operating problems quickly appeared when lubrication ceased. Needle bearing failures often caused damage to the pin and frame housings. The needle bearing was redesigned as a ZA-12 cylindrical sleeve bearing. ZA-12’s proven dry running properties made it well suited as a front axle bearing, eliminating the risk of housing and pin damage. Blade Lift Assembly Bushings — ZA-12 bushings also replace the steel sleeve bearings that supported the lift cylinders. The bushings were less expensive and easier to install than the steel bearings. In addition, they allowed designers to reduce the housing size. As a result, less housing material was used and, more importantly, operator visibility was improved.