This is where changing a toothed belt gets complicated with the closed polyurethane models that now equip a great many manufacturing lines, particularly in conveyor processes. Most are custom-made and delivered welded, hence closed. That closure, which gives them their strength, becomes a handicap when maintenance time comes.
To slide a closed belt onto its shaft, you first have to free the shaft itself. In practice, that means:
- removing the mechanical parts blocking access to the shaft,
- unshafting the line, a step that is often long and delicate,
- shutting down the whole process, including the other belts running alongside.
It is this last point that weighs the most. On many installations, several belts run side by side. Replacing just one of them then forces you to stop and unshaft the entire line, even when the other belts are in perfect condition.