Maintenance inspection engineer found negligent

A recent court case involving the collapse of a bucket wheel excavator at a coal mine shows that engineers and maintenance personnel need to be thorough in performing seemingly inconsequential or minor services.

Engineers are often asked to inspect and certify works. As the inquiry showed, engineers need to gain access to all parts of the machinery, and if this is not possible, this lack of access should be documented in the inspection report.

The BHP Coal Goonyella Riverside Mine used an O&K Orenstein bucket wheel excavator (BWE) for 18 years, until it suddenly collapsed due to a fracture in its central tower. An O&K employee had previously suggested steel stiffeners be welded onto the main tower, and the crack which eventually led to the collapse started at the end of one of these stiffeners. The collapse caused losses of over $50m.

O&K was found to be negligent in its design of the stiffeners, and inspections-provider Krupp Engineering was also sued. In 1999, the company had sent an engineer to inspect the entire BWE, but he failed to notice the crack developing at the top of the stiffener because he did not look there.

Had he used a mirror or a cherry picker to access the difficult-to-see section of the equipment, he would have been more likely to have detected the crack. The engineer was found to have breached his duty of care by not gaining a sufficient vantage point for the inspection of the critical area.

Both the engineer and Krupp were found negligent in the inspection and in writing the report. Krupp was found in breach of contract under the Trade Practices Act 1974, and found liable for misleading and deceptive conduct because of the inaccurate report.