Had a boom section start to slide on a Manitowoc 2250 last Thursday
We were setting a 12-ton HVAC unit on a roof in Dallas, about 80 feet up. I felt a weird shudder in the cab, looked up, and saw the outer boom section had shifted nearly 6 inches. I dropped the load to the roof deck immediately. The pin lock had worked itself loose over the morning's lifts. It was the kind of thing you check at the start of a shift, but it can creep on you. Who else has caught a boom walk like that? What's your routine check for those pins?
Saw a buddy's rig do that on a bridge job. His lock pin sheared clean through after a long day of swinging pipe. Now I rap every pin with a hammer before the first pick, no exceptions.
Taylor.jessica is right about that pin check after every lift... I read a report from a guy on a forum who said his boom walked three inches on a 999 in San Antonio because he skipped just one check before the last pick of the day. That hammer rap test works if you're consistent.