Australia Post used ball transfer tables for manual sorting of bulky international mailbags weighing up to 35 kilograms. This required substantial, repetitive manual effort by operators to push, pull and rotate the bags, exposing the operators to potential musculoskeletal injury. To address this issue, Australia Post looked for alternative solutions that would substantially reduce operator input and exposure to risk of injury. With a targeted push/pull force of 50N (5kg) for a 35kg bag, it was acknowledged that this target would most likely require a powered solution, adding to operating and maintenance costs.

The Rotacaster Solution: Rotacaster proposed a manual transfer solution utilising their 48mm Rotacasters combined with polyacetal (POM) spacer rollers. The roller’s smaller diameter was designed to provide support for the soft packaging, while minimising friction and reducing the number of Rotacaster wheels required. Australia Post and Rotacaster collaborated on the design and construction of the transfer table. Trials were successfully undertaken at an Australia Post gateway.

Outcome: The solution resulted in a significant reduction of push/pull forces to between 40 and 70N (4-7kg) in all directions on the table. Australia Post considered this a remarkable achievement in the absence of any powered assistance.

Additional Advantages: In addition to reducing the push/pull forces required, without the cost, noise, and maintenance associated with a powered solution, the polymer surfaces of the Rotacasters and spacer rollers have demonstrated a lower affinity to adhesion of labels and stickers from packages, further reducing downtime and maintenance costs.