Uncontrolled Gas Flow
Effective Date: 5/5/1977
 | Minerals Management Service Gulf of Mexico OCS Region |
Notice No. 064
May 5, 1977
OCS Operations Safety Alert
Uncontrolled Gas Flow
An uncontrolled gas flow recently occurred on an offshore platform drilling rig when a grease fitting blew out of a safety valve.
The drilling rig crew was running a 7" liner on 4" drillpipe when the well started flowing through the drillpipe. A safety valve was installed on the drillpipe and the blowout preventer pipe rams were closed. Well-killing operations were underway when a grease fitting on the safety valve blew out. This allowed uncontrolled flow of the well. The annulus was opened through the choke and the flow diverter system. A potentially hazardous condition developed when a combustible atmosphere surrounded the platform and all personnel were evacuated. Two days later the well bridged and the flow ceased. Extensive platform remedial work was necessary before drilling operations could be resumed.
There were no injuries to personnel and no fire or pollution.
To prevent a recurrence of this accident the operator has taken the following action:
1. All grease fittings on safety valves and kelly valves in the field have been removed and replaced with solid plugs.
2. These valves were then tested to their rated working pressure.
[signed] D.W. Solanas
Oil and Gas Supervisor
Field Operations
Gulf of Mexico Area