Alert 07 – 05 Incident Involving the Link Tilt Results in an LTI
WHAT HAPPENED:
After releasing the elevators, the derrickman was pulling back a stand of drillpipe when the driller simultaneously retracted the link tilt. As the elevators returned to over well center the chains connecting the link tilt to the bale arms took the weight of the bales and elevators, causing a shuddering action on the link tilt system. This caused the link tilt intermediate stop bar to pass the intermediate stops resulting in the link tilt fully extending at an uncontrolled speed striking the derrickman.