Pre-Start Check Finds a Weeping Brake
At the start of the shift you carry out the daily inspection. The crane is a 2019 hammerhead, 55 m jib, with a trolley and a hoist fitted with an electromagnetic brake. During the walk-round you notice a thin film of oil on the underside of the hoist brake housing and a faint burnt smell near the motor. The brake holds a 1 t test load without visible slip when you apply it, but the smell persists after two test applications. The previous shift's log notes 'brake felt soft' with no action recorded. The site is under programme pressure and the supervisor says the brake 'held the test load, so it's fine'. The manufacturer's manual lists brake adjustment and lining inspection at 250 hours; the hour meter shows 1,840 hours since the last recorded brake service.
1. Decide whether the crane is fit for service and justify the decision.
Read the worked answer
The crane is not fit for service. Three findings point the same way: oil weeping from the brake housing suggests seal or lining contamination; the burnt smell suggests the lining has been overheating or slipping; and the brake is 1,840 hours past a 250-hour service interval, so the adjustment and lining inspection are long overdue. A single successful static hold of a 1 t test load does not prove the brake will hold a rated load dynamically, and a contaminated or glazed lining can hold once and fail under heat or repeated duty. The previous 'soft' note is an unresolved defect. The crane should be taken out of service, the defect logged and reported, and the brake inspected, cleaned or adjusted and the lining replaced as required by the manufacturer before return to service.
2. What records and follow-up actions are required?
Read the worked answer
Record the defect, the oil film, the smell, the overdue service and the decision to stop the crane in the log, and notify the responsible person. Raise a maintenance request and confirm the brake is inspected to the manufacturer's procedure, with adjustment and lining condition recorded. Do not return the crane to service until the defect is signed off. Review why the 250-hour interval was missed and correct the maintenance schedule. The supervisor's 'it held the test load' argument should be recorded and overridden with reasons.