Page 316 - Drilling Technology in Nontechnical Language

Chapter 13 – DRILLING PROBLEMS AND SOLUTIONS 307

Slots can also be cut into the conductor pipe and positioned just
above the seabed (fig. 13–2).

While using these techniques, maintaining primary well control and
monitoring for potential kicks must not be compromised. The risks are
different for an exploration well than for a development well.

Fig. 13–2. Slotted conductor

Fractures are a real cause for worry. If the fracture extends to surface,
the rig itself might collapse if the strength of the ground underneath is
compromised due to the fractures and the lubricating effect of mud in
the fractures.
These surface hole losses must be cured, and the only effective way is
by pumping cement into the well and ensuring that the cement sets in the
fractures close to the wellbore. The procedure for placing cement in the
right location while it sets is described later.

_Devereux_Book.indb 307 1/16/12 2:13 PM