Corus Northern Engineering Services (CNES) is using acoustic emission techniques to monitor the condition of the main hoist gearboxes on 500-tonne cranes used in steelmaking.
The casting crane and the teeming crane being monitored are used to hoist ladles containing molten iron at the company’s BOS (Basic Oxygen Steelmaking) plant in Scunthorpe.
CNES said acoustic emission monitoring techniques are ideal for monitoring the condition of critical, slow-moving (0.25-80rpm), high capital value plant and machinery, particularly where there are fluctuating load conditions and where a breakdown would have a significant impact on production.
CNES engineers use a portable monitoring system, Aquilla AE Pro I-MON, to monitor the condition of the overhead cranes, which are driven through two large epicyclic gearboxes. After a year of collecting data, it can now be used to predict the life of the gearboxes.
The two crane gearboxes are normally returned to the manufacturer for refurbishment after a maximum of five years of service. By monitoring the condition of the gearboxes with acoustics, the life of the gearboxes could be increased, saving on refurbishment costs. Any internal damage to bearings or gear teeth that occurs earlier can also be picked up earlier than with the traditional planned maintenance, and the necessary repairs can be scheduled during the next available shutdown period.