Risk-Based Inspection Model for Heat Exchanger Tube Bundles

eat exchangers are widely used by many industries such as petrochemical, power
generation, and oil and gas industries. The safety while operating heat exchanger
is heavily concerned. Hazard of heat exchanger especially in those industries may
end up with risk related issues. Many companies nowadays apply the conditionbased
inspection programs whereby the bundle life is predicted by analyzing the
history of each exchanger bundle since the service start date. As the result, the
financial consequences will not be considered associated with the bundle life while
analyzing the reliability of the exchanger. Thus, an effective risk assessment model
is required to assess failures associated with heat exchanger and to achieve plant
availability and efficiency. This study presents the development of a risk-based
inspection model for heat exchanger. The project is carried out to assist
operator/user that operates heat exchanger to develop a customized maintenance
optimization tool for selecting cost effective and appropriate maintenance and
inspection tasks and techniques in determining the risk level of mode of failures
associated with the heat exchanger. A comprehensive literature review related to the
project topic is carried out from several journals and books available and being
analyzed which consist of the overview of the Risk-Based Inspection (RBI) model,
analysis of some of the existing RBI model, the overview of heat exchanger,
description and analysis of currently used semi-quantitative risk assessment matrix
method and the application of Microsoft Excel and Visual Basic Applications (VBA)
in developing RBI model. Apart from that, Weibull distribution will be discussed
further to understand its use in determining the probability of failure through life data
analysis. The application of Microsoft Excel is proposed to ease the process of
inspection by using the developed RBI model. Then, the program built will be
validated with several available software in the market such as Weibull++ and
RBI developed by Reliasoft Corp. The sample of validated historical data of
inspection of heat exchanger from API RBI will be used to justify the risk level for
each failures associated by applying the life data analysis. The scope of study for this
research include establish the life data analysis by using Weibull analysis, analyze the
risk value associated with several modes of failure and propose the inspection plan
based on the result of analysis.