Subsea diverting is new option for shallow gas

Journal Article · Mon May 05 04:00:00 EDT 1986 · Oil Gas J.; (United States)

OSTI ID:5562906

Roche, J R; Anderson, J O

A new method for subsea gas diverting has been developed. It offers additional well-control options for handling kicks from very prolific shallow gas sands. A shallow gas blowout aboard the West Vanguard semisubmersible off Trondheim, Norway (wildcat well 6407/6-2), in October 1985 resulted in one fatality and extensive rig damage. More than 4 months after the initial kick, the formation continued to flow. Gas-charged sands were penetrated at 300 m drilling depth at an estimated formation pressure of 900 psi. Eyewitness accounts and assessment of damage raise serious questions about the capability of a surface-diverter system to handle a flow of such extraordinary severity. Steel pipes were quickly cut out by erosion. An explosion and fire was experienced while the crew was abandoning the rig. In the wake of this and other accidents, much study was devoted to devising a more comprehensive means of handling shallow gas kicks. It was concluded that, while a surface diverter system can handle the flow from some shallow gas pockets, stronger measures were needed to deal with exceptionally prolific zones such as 6407/6-2.

• Research Organization: Hydril Co., Houston, TX
• OSTI ID: 5562906
• Journal Information: Oil Gas J.; (United States), Journal Name: Oil Gas J.; (United States) Vol. 84:18; ISSN OIGJA
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
42 ENGINEERING
423000 -- Engineering-- Marine Engineering-- (1980-)
ACCIDENTS
ALLOYS
BLOWOUT PREVENTERS
BLOWOUTS
DEPTH
DIMENSIONS
DRILLING RIGS
EROSION
EUROPE
EXPLOSIONS
FIRES
IRON ALLOYS
IRON BASE ALLOYS
MEDIUM PRESSURE
NATURAL GAS WELLS
NORWAY
OFFSHORE PLATFORMS
OIL WELLS
PIPES
RESEARCH PROGRAMS
SCANDINAVIA
STEELS
WELLS
WESTERN EUROPE