RE: Drilling day 3629 Oct 2019 21:30
Its a good choice for hard rock, It involves leaving the productive reservoir section without any tubulars. The advances in interventions such as coiled tubing and tractors means that barefoot wells can be successfully produced.
Advantages like -
Full exposure of reservoir zone
No cementing or perforating expense
Minimize formation damage
Minimize flow path restriction due to cementing and perforating
Minimize wellbore skin
Improve wellbore performance due to a large inflow area
There is no final casing string, the well is completed in Open Hole.
The formation needs to be competent, to prevent collapse & loss of production. Often extended reach horizontal wells are completed 'Barefoot' as casing strings may be hard to get to TD.
The advantages are that the well cost less (one less casing string, cement job, perforations etc.), and there is less contamination (formation damage) of the producing zone. Logging is more accurate in open hole, as the signals do not need to go through a metal casing. Additionally production is unimpeded by perforations.
Barefoot completions are often used in the upper part of reservoirs where water is not a problem.