Alert 00 – 27 Auxiliary Brake
Alert 00 – 27 Auxiliary Brake
WHAT HAPPENED:
Prior to “Stage 2” of a cement job, the blocks were raised above the casing stump and locked into position using the Auxiliary Brake with the elevators remaining attached; the stump was approximately 13 feet (4m) above the rig floor and the brake was not chained down During the cement job, the motorman proceeded to rig out part of the rig and disconnected the glycol system for the auxiliary brake. This action caused the air pressure to dissipate causing the Auxiliary brake to become disengaged. The blocks started to come down, hit the collar of the casing and laid over into the derrick.