TITLE:
Analysis on the Failure Causes of the Collapsed Tubing in an Oil Well
AUTHORS:
Jun Wu
KEYWORDS:
Tubing, Failure Analysis, Collapse, Complex Working Conditions
JOURNAL NAME:
World Journal of Engineering and Technology,
Vol.11 No.4,
November
6,
2023
ABSTRACT: Due to
the influence of multiple factors such as internal and external formation and
mechanical pressure, medium corrosion and construction operation environment, a
tubing collapse failure occurred in an oil well. In order to determine the
failure cause of the tubing, physical and chemical tests and mechanical
properties analysis were carried out on the failed tubing sample and the intact
tubing. The results show that the chemical composition, ultrasonic and magnetic
particle inspection, metallographic test, Charpy impact energy and external pressure
mechanical property test of the failed tubing all meet the requirements of API
Spec 5CT-2021 standard, but the yield strength of the failed tubing does not
meet the requirements of API Spec 5CT-2021 standard. Through the analysis of
the working conditions, it can be seen that the anti-extrusion strength of the
tubing collapse does not meet the API 5C3 anti-extrusion strength standard. The
failure type of the well tubing is tubing collapse caused by large internal and
external pressure difference.