Pre-start inspection findings on a crane that was 'fine yesterday'
It is 06:30 and you are the first on site. You are to unload timber from a truck using a vehicle loading crane that another operator used the previous afternoon. During your pre-start inspection you find: the hydraulic oil level is just below the minimum mark on the sight glass; there is fresh oil misting around one outrigger cylinder gland; the hook latch is stiff and does not spring closed fully; the load moment indicator powers up but shows a sensor fault code; and the slew brake holds when tested but the slew creeps slightly when parked on a 3 degree slope. The previous operator's handover note says 'all good'. The delivery truck is waiting at the gate and the site supervisor wants the timber off the truck within the hour because the truck is booked elsewhere. The crane's service record shows the last inspection was 11 months ago.
1. Which of these findings stop the lift, and why? Distinguish between items that must be rectified before use and items to monitor.
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Stops the lift - load moment indicator fault. The LMI is a safety device that warns and limits against overload and is required to be functioning. A sensor fault code means the system cannot be trusted to indicate load or radius correctly, and on many cranes it will inhibit operation or should. I would not operate with a known fault in the rated capacity limiter or indicator. It needs diagnosis and clearance by a competent person.
Stops the lift - hydraulic oil below minimum and oil misting at the outrigger gland. Low oil can cause cavitation, poor function and overheating, and the leak means the system is losing oil and the outrigger may not hold. An outrigger that bleeds down under load changes the machine's level and geometry during a lift. Both need attention before use.
Stops or restricts - hook latch not springing closed. A defective latch allows the sling to escape the hook under slack or load reversal. It must be repaired or the hook replaced; it is a quick fix but not optional.
Monitor/assess - slight slew creep on a slope. Slew brakes are not parking brakes for holding a suspended load, and creep on a slope is a warning that the machine should be levelled before work. I would set up level and confirm the brake holds; if creep persists on level ground, it is a defect.
Also relevant: the last inspection was 11 months ago - check the required inspection interval and whether it is current.
2. The supervisor says the truck must be unloaded within the hour. Set out how you would respond and what would happen before any lift.
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I would tell the supervisor clearly that the crane is not fit for use this morning and that the one-hour deadline cannot override that. I would explain the specific findings - LMI fault code, oil below minimum, active leak at an outrigger, defective hook latch - in terms of consequence, not just as a list, so the supervisor understands the risk is a real overload or outrigger collapse, not paperwork.
I would take the crane out of service: isolate it, tag it, and ensure no one else starts it. I would notify my supervisor and the person responsible for the crane's maintenance, and record the findings and the time in the pre-start record and site diary, including the handover note's 'all good' entry and the discrepancy.
Practical options for the deadline: arrange another crane or a different unloading method, or have the delivery rescheduled. The truck's booking is a commercial problem, not a reason to operate a defective crane.
The crane returns to service only after a competent person rectifies the faults, the LMI is cleared and function-tested, the leak is repaired and oil topped up, the hook latch is replaced, and the machine is confirmed level and the slew brake checked. The rectification and clearance would be recorded before the next lift.