Operator in Trinidad & Tobago uses Petromac to prevent tool rotation in 12.25” hole
Preventing rotation of imaging tools is desirable to prevent image overlap. This is particularly important in large wellbores where borehole coverage is lower.
Traditional methods to prevent/mitigate OBMI rotation include running swivels to release cable torque and performing multiple passes over zones of interest.
By using Tool Taxis the imaging tool becomes ‘locked’ into a fixed orientation, which prevents tool rotation. An operator used this technique to prevent the tool from rotating on a dual OMBI job in Trinidad & Tobago and obtained an excellent log in 12.25” hole.
Micro-resistivity imaging tools such as OBMI, FMI and NGI are also negatively affected by stick slip motion caused by overpulls. Petromac Tool Taxis help to smooth the tool motion, and the result is clear, crisp imaging logs.
Preventing rotation of imaging tools is particularly important in large wellbores where image coverage is lower.
Petromac Tool Taxis were used on the OBMI to prevent the sonde from rotating.
High quality logs were obtained with no rotation. The logs were also devoid of any stick slip artifacts due to the smooth tool motion caused by the Tool taxis.
Holefinder system facilitates wireline logging in an ‘impossible well’ in Iraq
Near Vertical ‘Impossible Well’ Logged in Iraq
An operator in Iraq was combating major issues with wellbore ledges in a well with only 6 deg deviation. After two wireline runs which were held up at shallow depth, the operator undertook a wiper trip, only to experience similar problems again on the 3rd attempt. The decision was made to run a TLC operation, however this was also unsuccessful.
In all a total of 5 days of rig time had been lost trying to pass a 20” washout with associated ledge.
Frustrated with the lack of results from conventional wireline and TLC, the operator sought the expertise of Petromac to log this critical well. A total of 6 descents were made with Petromac Wireline Express – all seamlessly conveyed to TD.
Without a holefinder, wireline toolstrings are easily held up by ledges and washouts.
Using the Wireline Express holefinder, the toolstring does not loose any momentum as it slides over wellbore obstructions.
In ‘vertical’ wellbores large ledges will persistently holdup toolstrings, even on TLC operations.
Petromac Tool Taxis ensure that the angled holefinder is always oriented upwards, allowing the toolstring to slide seamlessly over ledges.
A well which could not be logged on TLC was subsequently logged using the Petromac holefinder system (6 successful runs in hole).