Drilling 8-1/2" hole out of 13-3/8" casing

28 January 2009 We are looking at drilling an 8-1/2” hole out of a 13-3/8” casing
with 30 feet of cement inside. Have you seen this before? Split
decisions in here as to whether run a 12-1/4” clean out string first
or just go for it with an 8-1/2” BHA.

What experiences have other forum members got, including :
1. Did you ever have problems with cement blocks if no clean-out run
2. What precautions taken if clean-our run not made
3. Any constraints on 8-1/2" BHA components

What would you do???

Thanks

Chaz Taylor
PEDL, UK

4 Answer(s)

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