Equipment Failure - Broken Gear

While performing a lift using a tower crane, a failure of the gearbox cause about 1.000 lbs of hook and rigging gear to fall to the ground, narrowly missing workers in the area. Here is the report.

The investigation revealed several issues, most relating to proper inspections of the gearboxes to identify defective gears.  While again this appears to be a straight equipment failure, we would also want to know:

  • How did the deficient gear end up in the gearbox (it was the wrong material)?
  • Are we looking for repeat failures (this had happened before)?
  • How close were the workers in the vicinity?
  • What was the preventative maintenance plan for this gearbox?  Was it required be the vendor?

Lots of other directions a good investigation will lead you.