When a stuck pipe situation happens, personnel on the rig must correctly identify a stuck pipe mechanism.
Why is it so important to determine the mechanism of stuck pipe?
If you know the cause of stuck pipe, you will be able to free your pipe correctly. However, if you cannot correctly identify a root cause of stuck pipe, your drill string may be in the hole forever!!!
Many people in the oil field, including me, use the guidelines from the famous stuck pipe prevention book, named “TRUE,” which belongs to Amoco. It is extremely useful and so easy to understand.
This is the stuck pipe table.
How can you use the table?
- Select the situations that you see and circle all the figures in the same row.
- Add all figures for each column
- The highest score indicates the stuck pipe mechanism
Let’s see the example
Pipe motion prior to sticking? – The pip can be moved down before sticking = Move down (1, 0, 2)
Pipe motion after sticking? – The pipe has restriction while moving down= Down Restricted (1, 0, 2)
Pipe rotation after sticking? – The pipe can be rotated freely after sticking = Rotate Free (0, 0, 2)
Circulating pressure after sticking? – The circulation can be done without any pressure changes = Circulation Free (0, 2, 2)
Total score = (2,2,8)
The highest score is wellbore geometry; therefore, the most likely possible mechanism of stuck pipe is wellbore geometry.
Drilling formulas Stuck Pipe Prevention Book => Stuck Pipe Prevention Book