Tool Taxis successfully convey an Array Sonic to 79° deviation in open hole
An operator in Abu Dhabi wanted to log an Array Sonic in a 8.5” open hole well which featured an 800ft, 79° tangent section. The preference was to complete the logs on wireline and to avoid pipe conveyance, there by improving data quality and rig efficiency.
Traditional methods of centralizing the Sonic tools using powered calipers, standoffs, bowspring centralizers etc. cause drag and make it impossible for a toolstring to descend to high deviations by gravity. By replacing the traditional centralizing accessories with Tool Taxis, the toolstring was able to descend effortlessly to 79°. Further details of this technique can be found in SPE paper SPE-192876-MS.
Array Sonic tool with high-drag traditional centralizing equipment (left) and with low-drag Petromac equipment (right).
Centralizing Array Sonic tools typically involves adding drag inducing centralizers (powered calipers / bowsprings) which limit the maximum deviation the tools can descend to under gravity alone.
The Array Sonic was run on Tool Taxis, removing the need for PPCs, standoffs, LCMEs etc.
The toolstring was able to descend freely to 79degrees
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).