PDC, tertiary drilling, inhibitive WBM experiences?

24 September 2010 Current experience i.e. as section length and well's TVD's deepen.
i.e. >2500m TVD suggest that chip hold down effects on PDC's using highly inhibitive water based muds still has a profound effect. i.e. Kills ROP significantly, notably in the lengthier shale sequences!

Therefore we are seeking discussion on recent experiences of drilling offshore wells, tertiary, inter-bedded marine 'shale' drilling environments, using PDC's and highly inhibitive water based muds.

Specific bit design features?
No of blades, cutters, other design features to consider?

Bit type, e.g. tri-cone, often just as good?

Drilling fluid rheologies, additives?

Importance of bit/bottom hole cleaning or not?

Parameter to be appplied, design for lighter WOB or ram and cram and end up with the provervbial 'ring out' sooner vs later?

All comments welcomed.

Regards,

Peter Aird

2 Answer(s)

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