Schlumberger

Technical Paper: Drilling Dynamics Overview for Deepwater Gulf Of Mexico Salt Drilling

Society: AADE
Paper Number: 09-ntce-17-05
Presentation Date: 2009
 

Abstract

The probability of drilling into salt in the average Deepwater Gulf of Mexico (GOM) well is extremely high. Some operators have even planned bottomhole assemblies (BHAs)/hole Sections through no less than five salt intervals. Obtaining the well total depth (TD) under authority for expenditure (AFE) requires optimizing drilling of these salt sections by choosing the most economic and reliable bit/BHA/reamer combination to keep rate of penetration (ROP) high while simultaneously mitigating shocks and vibrations in the components of the BHA.

This paper highlights BHA dynamics of multiple BHAs by focusing on overall drilling dynamics and bit/reamer performance of the most popular hole sizes, 18 1/8 in x 21 in and 14 3/4 in x 16 1/2 in. These techniques guide informed decisions on bit/reamer selection and drilling parameters that maximize penetration rates without sacrificing BHA longevity. A strong focus on shock mitigation is crucial for any successful salt drilling run. Lessons learned from multiple runs in multiple fields highlight the drilling practices that make a BHA run successful.