RELIABILITY ANALYSIS OF CORRODED GAS PIPELINE TYPE API 5L X-52 ON RAMBUTAN-BETUNG LINE

• Main Author: AFRYANTO (NIM 12104054), LIDYAN
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/10801
• Institution: Institut Teknologi Bandung

Reliability Analysis has been done on gas transmission pipeline Rambutan-Betung Sumatera Selatan Line which has 21.2 Km in length. This line has been installed since 1976. In calculation, this line divided into four segments and each segment consists of 50 sub-segments. The main data was retrieved from Intelligent Pig by Rosen in 2000. Maximum Allowable Operating Pressure (MAOP) analysis has been done on 8 pipe critical points in this line which has not been repaired until 2008.<p>First Order Second Moment Method (FOSM) was used as reliability analysis method. Limit state used was g = oys - oHS. With that limit state, the value of reliability for each segment can be calculated. Actual Probability of Failure (PoF) of a pipe can be calculated from that reliability value. By determine allowed PoF's, it's get minimum allowable reliability value. The pipeline can be determined as over to its remaining life when its actual reliability value greater than allowed reliability value. Beside of reliability analysis test, there is also done the MAOP analysis test. The analysis has been done by two assumptions ; general metal loss and localized metal loss assumption. MAOP analysis with localized metal loss assumption used Folias Factor for the correction factor.<p>The result shows that reliability value for four segments pipeline that analyzed, was given the value below allowed minimum standard which determined. This result indicate that this pipelines have been exceeded their remaining life. So, it would be necessary to do mitigation for each critical point in each segment. MAOP analysis which has been done in same pipeline gives a different result. Based on general metal loss assumption, the result showed that in Km 0.21 the pipe has been over the remaining life in 2003, in Km 12.99 the pipe will be over the remaining life in 2009 and in other location, the pipe will be over the remaining life after 2012 (vary on each location). Based on localized metal loss assumption, the result showed that in Km 0.21 the pipe will be over the remaining life in 2015 and in other location the pipe will be over the remaining life after 2024 (vary on each location). The difference result between reliability analysis and MAOP analysis is caused by difference operation parameter in calculation and in safety factor.