New technologies (e.g. MPD) & Human Factors vs. well control basics
Recently there has been a succession of well control events for which root causes were associated with lack of understanding of the technology and associated procedures, leading individuals to forget basic rules such as shutting-in a well at the right moment in time.
This Well Control Lesson sharing is another example of risks induced by the introductions of new technology.
A number of lessons learnt from similar incidents have been contemplated and a thorough analysis captured in IOGP info sheet ‘Managing the introduction of new technology in well operations’. This document can now be downloaded at Managing the introduction of new technology in well operations | IOGP Publications library.
In this case the lack of communication between Geologist and Drillers did exacerbate the issue.
The IOGP Wells Expert Committee/Well Control Incident Subcommittee believes that this incident description contains sufficient lessons to be shared with the industry. We further encourage the recipients of this mail to share it further within their organization.
The incident occurred while drilling ahead a 12-1/4” section with MPD in a high angle well (MW 11.2ppg / static underbalance + Continuous Surface Back Pressure). A change in cuttings was observed and the shakers began blinding off. A gas spike at the shakers occurred and the well was Shut In.
Gain detected only when at surface, thanks to shaker overload & gas peak (postmortem gain evaluation to 80bbls).
Well control was properly managed:
What Went Wrong?:
Several factors contributed to the well control incident:
Corrective Actions and Recommendations:
PPFG trends to be plotted in real time against the PPFG prognosis used during the planning of the well. Any deviations from the plan need to be communicated to the operation team in a timely manner. Communication protocols need to be established and tested to allow this to happen effectively. Any changes in PPFG need to be evaluated against the design assumptions, and the implications understood by the operations and engineering teams.
The vendor to proceduralize requirements for RCD bearing usage including installed hours before a hard redress and maximum leakage rate.
Document MPD Strategy, including the following:
Reference IOGP info sheet Managing the introduction of new technology in well operations | IOGP Publications library
safety alert number: 326
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