Escalator repair and maintenance

Escalator repair and maintenance: how it works

An escalator wears differently from a lift: it carries load almost continuously, so the first to go are the step chains, rollers, comb plates at the landings and the handrail, which stretches over time and starts lagging behind the steps. During inspection we check side clearances and step play, chain tension and elongation, the condition of the comb plates and skirt panels, and the operation of the safety switches.

We check the safety system fully and separately: the emergency stop buttons at the top and bottom, the comb plate switch, the skirt panel switches, the step chain break and over-elongation protection, the non-reversal device, phase monitoring and the electromagnetic brake. Each channel must be able to stop the steps on its own. If one of them has already been "bypassed" during a previous repair, we do not allow the escalator back into service until the protection is restored.

Repair means replacing steps in sets, overhauling the drive unit, the handrail and tension stations, rollers, bearings and the chain. For discontinued models, some parts have to be sourced from compatible alternatives or manufactured; we say so plainly, because it affects both the timeframe and the cost. Moving walks are built the same way, but on them it is trolleys that wear out the pallet band.

In a building that is open to the public, we work at night or outside opening hours: an escalator cannot be partly repaired while left running. Opening up the truss requires a fenced-off zone and a schedule agreed with the building management. We close off the area with solid panels, not tape - people step over tape without thinking. When escalators run as a parallel pair, it is usually possible to keep one direction in service.