Techniques for “nudging”
When formations are suitable (soft), jetting is the best technique to use.
The most common method is to use a mud motor of 9.5" OD or greater
with a 17.5" bit and a 1.5° bent sub. Using a 1.5° bent sub gives low build
rates and hence a low dogleg severity. The hole is then opened to the
required size after the mud motor run. Occasionally the job is performed
with a large mud motor and a 26" bit from the start. In this case either a
1.5°or 2° bent sub might be used.
When formations are suitable (soft), jetting is the best technique to use.
The most common method is to use a mud motor of 9.5" OD or greater
with a 17.5" bit and a 1.5° bent sub. Using a 1.5° bent sub gives low build
rates and hence a low dogleg severity. The hole is then opened to the
required size after the mud motor run. Occasionally the job is performed
with a large mud motor and a 26" bit from the start. In this case either a
1.5°or 2° bent sub might be used.
