Challenges evolve for directional drilling through salt in deepwater Gulf of Mexico

摘要

The following summarizes the major recommendations and lessons learned. Rotary steerable assemblies are the best option for drilling salt, with improvements seen in directional con trol, ROP and hole quality. RSS, in combination with motors, can deliver higher torque and RPM at the bit and can improve ROP over extended salt intervals. Include geomechanical considerations into directional design. Plan salt exit across a tangent section and at a flat or low dipping area of the salt base. Salt exit can be defined as a drilling target. Plan with low dogleg severity (<2.07100 ft). This ensures that if steering is required to counteract the salt tendency, the assembly still has enough capability to drill the desired trajectory Avoid drilling jars in hole sections larger than 18-in. PDC bits are best for salt. A general guideline is for heavy set bits with 16-mm or 13-mm cutters. Ensure bits are matched with under-reamer to avoid inducing shocks from incompatible bit-reamer combinations Control drilling parameters when entering and exiting salt until both bit and under-reamer are in similar for mations. 8. Real-time monitoring of salt drilling parameters, including shocks and vibrations, either at the rig-site or from remote centers, aids in optimizing drilling performance and extending BHA life.