Private Forums
Fishing for 26" Bit
12 July 2018
Evening all.

Just had a 26" bit back off a 36" H/O BHA. We drilled the 26" to +/-300m & were under-reaming to 36" at +/-220m when we got the dreaded drop in SPP. 
Interestingly, the bit is wedged at an angle at 220m. We've attempted to re-engage with the bit-sub - no joy. LIB is a little unclear but appears to show the edge of the lug, so the bit is tilted in the hole.
Current options we're thinking of include:
1) Making some toothed-washover-pipe-type tools with 26" casing.
2) Hammer the thing to bottom with mills & re-try with home-made tools
3) One of the fellas here has heard tell of explosives being used to break up large fish like this, prior to fishing with either washover pipe or RCJB.

Don't really want to consider the nuclear option of a re-spud.
Be very interested in ideas, experience on this.
3 answer(s)
Total Posts: 119
Join Date: 05/03/08
Hi Phil,

Firstly I would very strongly advise against the use of explosives. I did it once in a similar situation and it just made the problem much, much worse.

Ended up with lots of different sized and shaped pieces of junk that were a nightmare for fishing and we never got it all out.

We also used a large enough charge that we developed lost circulation to the seabed (JU Rig drilling through a conductor), but could also be a concern depending upon the type of formation you are in (I presume you are Onshore Kurdistan?).

If 'poor-boy' fishing techniques don't work, my preference would be to shove it as deep as possible and side-track around it.
Drilling Engineer
Western Zagros
Total Posts: 2
Join Date: 12/07/18
Thanks for getting back Bara. I had mentioned that to the team - seems daunting to think of that just now but have to be realistic about fishing operations. Pinning hopes on a home-made affair from 26" casing...crossed fingers.
Drilling Engineer
Total Posts: 10
Join Date: 03/03/16
Seems difficult to retrieve the 26" bi. Many people will easily think that re-spud is the cheapest option.

If you choose to keep the hole, put cement plug and get OH sidetrack might be the other options.
Jump to top of the page