ALLOWABLE CORRODED PIPE PRESSURE ESTIMATION DUE TO INTERNAL PRESSURE AND LONGITUDINAL COMPRESSIVE STRESS

The pipeline is one of the important facilities in the oil and gas industry. It was being
used to transport oil and gas from one facility to other facilities. So the integrity of the
pipeline is the most important aspect that had to be considered in order to avoid the
unnecessary loss during the production. Due to that, certain standard codes have been to
determine the remaining strength of the corroded pipeline. In this project, the corroded
pipe pressure estimation due to the internal pressure and longitudinal compressive
stresses has been studied. The objective of this project is to estimate the allowable
corroded pressure of the corroded pipe due to the internal pressure and the longitudinal
compressive stress by using the finite element analysis software. The results obtained
from the finite element analysis will be compared with the available codes in literature.
The scope of study covers the integrity of the corroded pipeline due to the internal
pressure and longitudinal compressive stress based on the single corrosion defect. The
assessment will be carried out using the ANSYS software by generating the 3D models.
The compressive stress does influence the corroded pipe failure pressure estimation.
When higher longitudinal compressive stress is applied to the corroded pipe, the strength
of the pipe will be decreased.From ANSYS result, it can be concluded that the difference
between corroded pressure estimation by standard code and FEA is about 4% to 80% for
approach I while for approach 2 is about I 0% to 70%. The percentage of erorr in
approach I is higher compared to approach 2 because of the safety factors that were
included in the equation. These safety factors will reduce the corroded pipe pressure
estimation compared to the actual one.