Luis Ortega
ConocoPhillips
Scanning tubing at the wellhead using EMI technology has been a common practice in the Permian Basin and beyond. This application has been historically relied on to grade pipe and identify joints of the tubing string that require replacement due to wear, corrosion, pitting, or any irregularity that would compromise the integrity of the string and cause issues in general operations of the well. The tubing scanned on location has been thought to be accurately categorized and has been trusted to immediately reuse downhole within the same scope of work, given an acceptable reading. This practice poses an issue if scanning at the wellhead does not truly flag the compromised sections of pipe accurately and consistently.
The objective of this study was to determine the reliability of scanning tubing at the wellhead by cross-referencing the results of field scans to the more robust and trustworthy scanning practices performed in the pipe scanning yard. Scanning tubing in the yard is considered more accurate than field scanning due, primarily, to the pipe being machine cleaned (inside and outside) prior to being scanned. This cleaning method is known as brushing and rattling; a practice that is not performed in the field when scanning pipe out of the hole.
In this study, 15 tubing strings were used from wells across the Permian Basin for the testing process. 10 of which had each joint of tubing marked when scanned on location for the purpose of tracking the individual joints as they went through the yard scanning process to observe a direct joint-to-joint comparison between the field-determined grade and the official, yard-scanned, grade. This paper will cover the results of the tubing scan comparison and dive into workflow recommendations emerging from the findings of this evaluation.