Pre-installing under-reamer activation ball

Dear members

At a DWOP last month, we were discussing the plans to use under-reamers (UR)  in the well.  The primary UR will be a ball-actuated type.  It will be run above the LWD etc.  Below the LWD will be an 'on-demand' UR. They will be used in several hole sections.

One of our senior drill-crew members suggested that we pre-install the activation ball before RIH.  The UR rep said that wasn't feasible, but the drill-crew member stated that it had been done on his rig (reminds me of the saying, "Those who say that it's not possible, should get out of the way of those who are already doing it").

In fairness, we then discussed the fact that as soon as we started circulation then the UR arms would try to activate. This might make it difficult/damaging to drill out shoetracks and so on.

So, please can you share your thoughts and experiences on this suggestion.  Experience (facts) will be more valuable than opinions.

Let the debate begin!

Thanks

Dave

1 Answer(s)

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