Page 65 - Well Control for Completions and Interventions

56 Well Control for Completions and Interventions

flow into the well. Sadly, by the time the crew realized there was a problem,
it was too late. Mud oil and gas were blowing out onto the rig floor.
Although the crew were able to activate the BOPs annular preventer, the
high velocity of flow eroded and washed out both the elastomer seal and
the drill pipe; the well continued to blow out. Closing the variable bore
pipe rams (VBR) momentarily stopped the flow, but pressure building in
the drill pipe caused a rupture where it had eroded (at the annular pre-
venter). Oil and gas continued to flow onto the rig where it ignited. The
shear rams closed automatically, but failed to seal the well.
Macondo dramatically changed attitudes to training. It was clear from
the more measured and thoughtful reports on the accident that human
and organizational failings had been largely to blame. It was also clear that
well control training had failed. Some operating companies, recognizing
limitations in the standard International Well Control Forum and
International Association of Drilling Contractors (IWCF/IADC) well
control syllabus, began to develop their own in-house training courses.
Shell, e.g., developed advanced well intervention well control courses
that placed a greater emphasis on human factors and scenario-based exer-
e
cises. Using a new well intervention simulator, supervisors are subjected
to a range of well control emergencies. From the service sector, Maersk
Drilling have recognized the importance of human factors, and have inte-
grated it into their well control training. Other industry bodies were also
addressing human factors in well control training. In Europe, the “North
f
Sea Offshore Authorities Forum” performed a multinational audit that
examined “Human and Organisational Factors in Well Control.” 16 This
audit investigated:
• The engineering system.
How well control equipment controls are configured, and how
critical well control information is displayed for the user.
• Human factors.
Competency, situational awareness, availability of procedures, and
team working.

e
The well intervention simulator was developed by Drilling Systems Ltd. with support
from Shell. It includes wireline, coiled tubing, hydraulic workover, and rig-based
workover simulations.
f
The NSOAF has representatives from the regulatory authorities of the following nations:
The Netherlands, Denmark, Germany, Norway, The United Kingdom, The Republic of
Ireland, and the Faeroe Islands.