Transocean Drilling Rig Drops Traveling Block During Operations in GoM
The U.S. Bureau of Safety and Environmental Enforcement (BSEE) is responding to a significant equipment failure on board a Transocean ultra-deepwater semi-submersible drilling rig in the Gulf of Mexico, approximately 100 miles south of Fourchon, Louisiana.The offshore oil and gas operator, Shell Offshore Inc., reported that on June 9 the traveling block on board the Deepwater Nautilus fell during well operations.
Shell is monitoring the well and there are no reports of injuries to personnel or pollution, according to the BSEE. The project is limited to drilling and no production was affected by the incident.
BSEE engineers and inspectors have been discussing the on-going response with Shell and will travel offshore to the rig to investigate as soon as weather allows.
The traveling block is a large, freely moving series of pulleys or sheaves used to support the top drive which rotates drill pipe. On larger drilling rigs such as the Deepwater Nautilus, traveling blocks are often capable of handling loads in excess of 1 million pounds.
Built in 2000 for Transocean, the Deepwater Nautilus can drill to a maximum depth of 30,000 feet and is rated for water depths of up to 8,000 feet. The rig is similar in design to the Deepwater Horizon, which in 2010 exploded and sank in the Gulf of Mexico, killing 11 people and resulting in the worst offshore oil spill in U.S. history.
BSEE says it is investigating the incident and will provide more information as it becomes available. (
To sum it up: POH, set slips, spun pipe and picked up out of box. Alarm sounded and Driller set Brakes. ETs looked into alarm and reset fault on Drive. TD & Blocks started to drop, Driller pulled E-Stop. Drill Line parted. Need to replace Top Drive, Pipe Handler & Travelling Block.
[QUOTE=ENG.207;139109]To sum it up: POH, set slips, spun pipe and picked up out of box. Alarm sounded and Driller set Brakes. ETs looked into alarm and reset fault on Drive. TD & Blocks started to drop, Driller pulled E-Stop. Drill Line parted. Need to replace Top Drive, Pipe Handler & Travelling Block.[/QUOTE]
drilling line broke eh? I wonder if too old or overloaded or lack of preventative maintenance? Do you know if all the drillstring broke loose and went down into the well? Is the drillfloor all munged up?
Very thankful no one was hurt.
Not sure on all the factors but I dare say the drill line was not old/overloaded/lack of maintenance. Drill Line is on a constant change process as per ton miles or other operational factors. I can’t say for sure but they have a good record and history with Shell so I think Drill Line was ok. The Drill String was still set in the Slips, no damage there or below Rig Floor. The Drill House has some damage but nothing major. No other major damage done. Sounds to me the E-Brakes should have been set as soon as the alarm came in and definitely before ETs started tinkering.
[QUOTE=ENG.207;139117]Very thankful no one was hurt.
Not sure on all the factors but I dare say the drill line was not old/overloaded/lack of maintenance. Drill Line is on a constant change process as per ton miles or other operational factors. I can’t say for sure but they have a good record and history with Shell so I think Drill Line was ok. The Drill String was still set in the Slips, no damage there or below Rig Floor. The Drill House has some damage but nothing major. No other major damage done. Sounds to me the E-Brakes should have been set as soon as the alarm came in and definitely before ETs started tinkering.[/QUOTE]
agreed about ET’s but why did the drilling line break? There must have been one hell of a shockload when those brakes slammed on but you would think to break a drilling line would require more weight than just a traveling block and topdrive. That’s why I thought the drillstring must have been suspended at the time.
[QUOTE=c.captain;139118]agreed but why the drilling line broke? must have been one hell of a shockload when those brakes slammed on but you would think to break a drillingline would require more weight than just a traveling block and topdrive. That’s why I thought the drillstring was suspended at the time.[/QUOTE]
Ok, I see what you’re saying. But I don’t have a good answer. I’ll post more detail if it comes out.
There were quite a few things which came together to result in this mess…Primary cause was lack of communication and common sense. Long ago we were taught one thing - do not ever place faith in electrical or hydraulic brakes, when performing critical maintenance operations wherein the equipment under maintenance if it moves could cause potential damage or injury. Such a simple thing being not followed in addition to not having a thorough understanding of various PLCs in use and lack of good communication between the operators of the equipment and personnel performing maintenance, and you have a recipe for disaster. Thankfully nobody got injured!!