ST-80 Cylinder Failure Causes Lower Leg Fracture

What happened?

The crew was in the process of pushing liner to bottom. After completing the first connection of heavy weight drill pipe, the Floor Hand was moving the ST-80 (iron roughneck) back to its parked position.

While maneuvering the ST-80, the extend/retract hydraulic duplex cylinder suddenly failed. This caused the unit to fall outward and downward, and the control panel struck the Floor Hand’s lower leg with significant force.

After receiving initial medical care and stabilization, the Floor Hand was transported to the nearest healthcare facility.

The ST-80 extend/ retract hydraulic duplex cylinder has a threaded end that connects to a yoke underneath the unit. If the hydraulic duplex cylinder, the threaded connection or the yoke fails, the unit can fall forward and down to the rig floor.

Life Saving Rules

Line of Fire

Position yourself to avoid moving objects, vehicles, pressure releases and dropped objects. Establish and obey barriers and exclusion zones. Take action to secure loose objects and report potential dropped objects.

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