Download or read book Analysis of Metal loss Corrosion on Energy Pipelines Based on ILI Data written by Mohammad Al-Amin and published by LAP Lambert Academic Publishing. This book was released on 2012-08-01 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the models of calibrating the high-resolution in-line inspection (ILI) tools for sizing metal-loss corrosion defects and to characterize the growth of individual defects on energy pipelines. The models are developed in a Bayesian Framework. The calibration of ILI tools is carried out by comparing the field-measured depths and ILI-reported depths for a set of static defects. And the probabilistic characteristics of the parameters involved in the growth model are evaluated using Markov Chain Monte Carlo (MCMC) simulation technique based on ILI data collected at different times for a given pipeline. Moreover, a methodology is described to evaluate the time-dependent system reliability of a segment of a pressurized pipeline containing multiple active corrosion defects based on ILI data. Both the conventional Monte Carlo simulation and MCMC simulation techniques are employed in the methodology to evaluate the failure probability of the pipeline. The methodology considers three distinctive failure modes, namely small leak, large leak and rupture, and incorporates the hierarchical Bayesian power-law growth model for the depth of individual corrosion defect.

Download or read book Bayesian Analyses of Metal loss Corrosion on Energy Pipeline Based on Inspection Data written by Mohammad Al-Amin and published by . This book was released on 2012 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bayesian models are developed to calibrate the accuracies of high-resolution in-line inspection (ILI) tools for sizing metal-loss corrosion defects and to characterize the growth of individual defects on energy pipelines. Moreover, a methodology is proposed to evaluate the time-dependent system reliability of a segment of a pressurized pipeline containing multiple active corrosion defects. The calibration of ILI tools is carried out by comparing the field-measured depths and ILI-reported depths for a set of static defects. The measurement error associated with the field-measuring tool is found to be negligibly small; therefore, the field-measured depth is assumed to equal the actual depth of the defect. The depth of a corrosion defect reported by an ILI tool is assumed to be a linear function of the corresponding field-measured depth subjected to a random scattering error. The probabilistic characteristics of the intercept and slope in the linear function, i.e. the constant and non-constant biases of the measurement error, as well as the standard deviation of the random scattering error are then quantified using the Bayesian methodology. The proposed methodology is able to calibrate the accuracies of multiple ILI tools simultaneously and quantify the potential correlations between the random scattering errors associated with different ILI tools. The corrosion growth model is developed in a hierarchical Bayesian framework. The depth of the corrosion defects is assumed to be a power-law function of time characterized by two power-law coefficients and the corrosion initiation time, and the probabilistic characteristics of the parameters involved in the growth model are evaluated using Markov Chain Monte Carlo (MCMC) simulation technique based on ILI data iv collected at different times for a given pipeline. The model accounts for the constant and non-constant biases and random scattering errors of the ILI data, as well as the potential correlation between the random scattering errors associated with different ILI tools. The model is validated by comparing the predicted depths with the field-measured depths of two sets of external corrosion defects identified on two in-service natural gas pipelines. A simulation-based methodology is proposed to evaluate the time-dependent system reliability of a segment of a pressurized pipeline containing multiple active metal-loss corrosion defects. The methodology considers three distinctive failure modes, namely small leak, large leak and rupture, and incorporates the hierarchical Bayesian power-law growth model for the depth of individual corrosion defect. Both the conventional Monte Carlo simulation and MCMC simulation techniques are employed in the methodology to evaluate the failure probability. The methodology is illustrated using a joint of an underground natural gas pipeline that is currently in service.

Download or read book Probabilistic Modeling and Bayesian Inference of Metalloss Corrosion with Application in Reliability Analysis for Energy Pipelines written by Hao Qin and published by . This book was released on 2014 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: The stochastic process-based models are developed to characterize the generation and growth of metal-loss corrosion defects on oil and gas steel pipelines. The generation of corrosion defects over time is characterized by the non-homogenous Poisson process, and the growth of depths of individual defects is modeled by the non-homogenous gamma process (NHGP). The defect generation and growth models are formulated in a hierarchical Bayesian framework, whereby the parameters of the models are evaluated from the in-line inspection (ILI) data through the Bayesian updating by accounting for the probability of detection (POD) and measurement errors associated with the ILI data. The Markov chain Monte Carlo (MCMC) simulation in conjunction with the data augmentation (DA) technique is employed to carry out the Bayesian updating. Numerical examples that involve both the simulated and actual ILI data are used to validate the proposed Bayesian formulation and illustrate the application of the methodology. A simple Monte Carlo simulation-based methodology is further developed to evaluate the time-dependent system reliability of corroding pipelines in terms of three distinctive failure modes, namely small leak, large leak and rupture, by incorporating the corrosion models evaluated from the Bayesian updating methodology. An example that involves three sets of ILI data for a pipe joint in a natural gas pipeline located in Alberta is used to illustrate the proposed methodology. The results of the reliability analysis indicate that ignoring generation of new defects in the reliability analysis leads to underestimations of the probabilities of small leak, large leak and rupture. The generation of new defects has the largest impact on the probability of small leak.

Download or read book Reliability based Corrosion Management of Energy Pipelines written by Shenwei Zhang and published by LAP Lambert Academic Publishing. This book was released on 2014-05-21 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal-loss corrosion is a major threat to the structural integrity and safe operation of underground oil and gas pipelines worldwide. The reliability-based corrosion management program has been increasingly used in the pipeline industry, which typically includes three tasks, namely periodic high-resolution inline inspections to detect and size corrosion defects on a given pipeline, engineering critical assessment of corrosion defects reported by the inspection tool and mitigation of defects. The work reported in this book addresses the engineering challenges involved in the reliability-based corrosion management program, including the probabilistic corrosion growth modeling based on imperfect inspection data, time-dependent reliability evaluation, and optimal inspection interval determination for corroding pipelines.

Download or read book Corrosion and Reliability Assessment of Inspected Pipelines written by Rafael Amaya-Gómez and published by Springer Nature. This book was released on 2023-11-20 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides the most up-to-date, advanced methods and tools for risk assessment of onshore pipelines. These methods and tools are based primarily on information collected from ILI measurements and additional information about the soil surrounding the pipeline. The book provides a better understanding how the defects grow and interact (repulsion or attraction) and their spatial variability. In addition, the authors contemplate new defects that evolve between inspections and how they could affect the pipeline's reliability. A real-world case is presented to reinforce the concepts presented in the book. The book is structured into three parts: i) an introduction to onshore pipelines and the problem of corrosion, ii) a framework that deals with uncertainty for integrity programs for corroded pipelines, and iii) the applications of the methods presented in the book. The book is ideal for researchers and field engineers in oil and gas transportation and graduate and undergraduate engineering students interested in pipeline reliability assessments, spatial variability, and risk-based inspections.

Download or read book Development of Probabilistic Corrosion Growth Models with Applications in Integrity Management of Pipelines written by Shenwei Zhang and published by . This book was released on 2014 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal-loss corrosion is a major threat to the structural integrity and safe operation of underground oil and gas pipelines worldwide. The reliability-based corrosion management program has been increasingly used in the pipeline industry, which typically includes three tasks, namely periodic high-resolution inline inspections (ILIs) to detect and size corrosion defects on a given pipeline, engineering critical assessment of the corrosion defects reported by the inspection tool and mitigation of defects. This study addresses the core involved in the reliability-based corrosion management program. First, the stochastic process in conjunction with the hierarchical Bayesian methodology is used to characterize the growth of defect depth using imperfect ILI data. The biases, random scattering errors as well as the correlations between the random scattering errors associated with the ILI tools are accounted for in the Bayesian inference. The Markov Chain Monte Carlo (MCMC) simulation techniques are employed to carry out the Bayesian updating and numerically evaluate the posterior distributions of the parameters in the growth model. Second, a simulation-based methodology is presented to evaluate the time-dependent system reliability of pressurized energy pipelines containing multiple active metal-loss corrosion defects using the developed growth models. Lastly, a probabilistic investigation is carried out to determine the optimal inspection interval for the newly-built onshore underground natural gas pipelines with respect to external metal-loss corrosion by considering the generation of corrosion defects over time and time-dependent growth of individual defects. The proposed methodology will facilitate the reliability-based corrosion management for corroding pipelines.

Download or read book Reliability based Management of Buried Pipelines Considering External Corrosion Defects written by Seyedeh Azadeh Miran and published by . This book was released on 2016 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Corrosion is one of the main deteriorating mechanisms that degrade the energy pipeline integrity, due to transferring corrosive fluid or gas and interacting with corrosive environment. Corrosion defects are usually detected by periodical inspections using in-line inspection (ILI) methods. In order to ensure pipeline safety, this study develops a cost-effective maintenance strategy that consists of three aspects: corrosion growth model development using ILI data, time-dependent performance evaluation, and optimal inspection interval determination. In particular, the proposed study is applied to a cathodic protected buried steel pipeline located in Mexico. First, time-dependent power-law formulation is adopted to probabilistically characterize growth of the maximum depth and length of the external corrosion defects. Dependency between defect depth and length are considered in the model development and generation of the corrosion defects over time is characterized by the homogenous Poisson process. The growth models unknown parameters are evaluated based on the ILI data through the Bayesian updating method with Markov Chain Monte Carlo (MCMC) simulation technique. The proposed corrosion growth models can be used when either matched or non-matched defects are available, and have ability to consider newly generated defects since last inspection. Results of this part of study show that both depth and length growth models can predict damage quantities reasonably well and a strong correlation between defect depth and length is found. Next, time-dependent system failure probabilities are evaluated using developed corrosion growth models considering prevailing uncertainties where three failure modes, namely small leak, large leak and rupture are considered. Performance of the pipeline is evaluated through failure probability per km (or called a sub-system) where each sub-system is considered as a series system of detected and newly generated defects within that sub-system. Sensitivity analysis is also performed to determine to which incorporated parameter(s) in the growth models reliability of the studied pipeline is most sensitive. The reliability analysis results suggest that newly generated defects should be considered in calculating failure probability, especially for prediction of long-term performance of the pipeline and also, impact of the statistical uncertainty in the model parameters is significant that should be considered in the reliability analysis. Finally, with the evaluated time-dependent failure probabilities, a life cycle-cost analysis is conducted to determine optimal inspection interval of studied pipeline. The expected total life-cycle costs consists construction cost and expected costs of inspections, repair, and failure. The repair is conducted when failure probability from any described failure mode exceeds pre-defined probability threshold after each inspection. Moreover, this study also investigates impact of repair threshold values and unit costs of inspection and failure on the expected total life-cycle cost and optimal inspection interval through a parametric study. The analysis suggests that a smaller inspection interval leads to higher inspection costs, but can lower failure cost and also repair cost is less significant compared to inspection and failure costs.

Download or read book Modelling of External Corrosion Propagation for Buried Pipelines Based on Stochastic Processes written by Hui Wang and published by . This book was released on 2015 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pipelines are considered to be the most favored and reliable mode for transporting large quantities of gas/liquid. In recent years, because the pipelines are interconnected at a national and global level and because of increasing economic and regulatory constraints in dealing with aging and corroded pipeline systems, pipeline integrity management is an area of increasing relevance in the petroleum industry. Metal deterioration caused by corrosive soil is one of the major threats to the integrity of underground pipeline systems. External localized corrosion is one of the most common defects that can occur under normal operating conditions.In this Dissertation, we consider the external corrosion in pipeline structures in a probabilistic and dynamic manner. Multiple uncertainties from soil environment, pipeline structure, inspection process and maintenance are considered. The correlation between the spatial distribution of the external corrosion defects and the heterogeneous soil properties has been investigated. The correlation analysis is conducted by employing clustering techniques. As for the time domain, the long-time corrosion process is considered as a dynamic stable evolution process which contains three stages: nucleation, propagation and repassivation. In this study, the uncertainties introduced by the in-line inspections are investigated by using calibration methods and detection theories. Both random error and systematic error are assessed. Finally, a comprehensive pipeline maintenance strategy is proposed as an integrated solution to improve the efficiency of inspections and maintenances in industry practice.The contributions of this dissertation include: 1) a probabilistic model for the prediction of metal loss rate in underground pipeline structure is proposed. The model is able to account for the model uncertainty which comes from the imperfect prior knowledge and estimate the PDF of metal loss rate at a specified location. 2) A Bayesian approach for calibrating and estimating the actual external corrosion depth in buried pipeline structures based on an ultrasonic ILI inspection and the clustering technique was developed. We have taken the probability of defect existence into consideration. Hence a more realistic assessment of pipeline integrity can be achieved. 3) A clustering approach based on a hidden Markov random field is established for assessing the spatial distribution of external corrosion in a buried pipeline. The clustering approach presented in this study is easy to implement with the established ICM-EM algorithm. 4) A novel stochastic model framework for predicting the external corrosion growth in buried pipeline structures is presented and a time- and location- dependent maintenance strategy is established. We relate the soil properties with the corrosion growth propagation. The geometric Brownian bridge model was employed to present the corrosion rate evolution and hence is able to represent the inherent time-dependent dynamic property of corrosion growth.

Download or read book Underground Pipeline Corrosion written by Mark Orazem and published by Elsevier. This book was released on 2014-02-17 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: Underground pipelines transporting liquid petroleum products and natural gas are critical components of civil infrastructure, making corrosion prevention an essential part of asset-protection strategy. Underground Pipeline Corrosion provides a basic understanding of the problems associated with corrosion detection and mitigation, and of the state of the art in corrosion prevention. The topics covered in part one include: basic principles for corrosion in underground pipelines, AC-induced corrosion of underground pipelines, significance of corrosion in onshore oil and gas pipelines, numerical simulations for cathodic protection of pipelines, and use of corrosion inhibitors in managing corrosion in underground pipelines. The methods described in part two for detecting corrosion in underground pipelines include: magnetic flux leakage, close interval potential surveys (CIS/CIPS), Pearson surveys, in-line inspection, and use of both electrochemical and optical probes. While the emphasis is on pipelines transporting fossil fuels, the concepts apply as well to metallic pipes for delivery of water and other liquids. Underground Pipeline Corrosion is a comprehensive resource for corrosion, materials, chemical, petroleum, and civil engineers constructing or managing both onshore and offshore pipeline assets; professionals in steel and coating companies; and academic researchers and professors with an interest in corrosion and pipeline engineering. Reviews the causes and considers the detection and prevention of corrosion to underground pipes Addresses a lack of current, readily available information on the subject Case studies demonstrate how corrosion is managed in the underground pipeline industry

Download or read book Defect Assessment for Integrity Management of Pipelines written by Y. Frank Cheng and published by John Wiley & Sons. This book was released on 2024-04-02 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: DEFECT ASSESSMENT FOR INTEGRITY MANAGEMENT OF PIPELINES Make energy pipelines safer by improved defect assessment for integrity management Pipelines provide an effective and efficient mode for transportation of energies, including both conventional fossil fuels and renewable energies and fuels such as hydrogen, biofuels and carbon dioxide, over wide ranges and long distances, meeting economic development and civilian needs. While the integrity and safety of in-service pipelines is paramount to pipeline operators, there are many factors which can adversely affect the pipeline integrity and potentially result in pipeline failures and, sometimes, serious consequences. Defect Assessment for Integrity Management of Pipelines provides a thorough and detailed overview of various techniques that can be used to assess corrosion defects, the most common defects on pipelines, and other mechanical defects such as dents, buckles and winkles, all of which constitute essential threats to pipeline integrity. In addition to widely used standards and codes for defect assessment, readers can obtain the latest progress in development of advanced techniques for improved accuracy in defect assessment. From early-stage Level I methods to the newest Level III method integrating with the mechano-electrochemical interaction, Defect Assessment for Integrity Management of Pipelines has everything you need to improve safety of your pipelines. Defect Assessment for Integrity Management of Pipelines readers will also find: Evolution of defect assessment techniques and limitations to be overcome with improved techniques Detailed analysis of defect assessment for determination of fitness-for-service of the pipelines, and prediction of their failure pressures Both theoretical and practical aspects of the defect assessment methods applied on pipelines Defect Assessment for Integrity Management of Pipelines is ideal for pipeline professionals, researchers and graduate students to improve personal knowledge, research expertise, and technical skills.

Download or read book Integrity of Pipelines Transporting Hydrocarbons written by Gabriella Bolzon and published by Springer. This book was released on 2011-05-10 with total page 331 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes technical and practical aspects of pipeline damage. It summarizes the phenomena, mechanisms and management of pipeline corrosion in-service. The topics discussed include pipelines fracture mechanics, damage mechanisms and evolution, and pipeline integrity assessment. The concept of acceptable risk is also elucidated and the future application of new knowledge management tools is considered.

Download or read book Analysis of Pipeline Steel Corrosion Data written by nist and published by Createspace Independent Publishing Platform. This book was released on 2013-11-12 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Currently, the U.S. has over 3.7 million kilometers (2.3 million miles) of pipelines crossing the country transporting natural gas and hazardous liquids from sources such as wells, refineries, and ports to customers. It is estimated that almost 2/3 of the energy consumed in the U.S. passes through a pipeline at some point between its origin and the point of consumption and pipelines account for about 20% of the total mass-distance that oil and natural gas are transported [1,2]. Clearly, the maintenance of an uninterrupted energy supply to the public requires the operation of these pipelines in such a manner that corrosion does not result in an unscheduled interruption to the flow of these energetic materials to the nation, as occurred recently in Alaska [3]. This task is accomplished by pipeline operating companies, who follow standards, codes, and practices set out by variety of regulatory agencies, industrial consortia, and standards developing organizations. the Pipeline Standards developing Organizations coordination Council (PSDOCC) coordinates the activities of these groups and the Department of Transportations Office of Pipeline Safety (OPS) is the main regulatory agency with final responsibility over this system of codes and practices [2].

Download or read book Remaining Strength Assessment of Deteriorating Energy Pipelines written by Bipul Chandra Mondal and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Pipelines are extensively used as the most economic means of transporting oil and gas. The steel pipelines have been widely used for these applications due to the high strength to weight ratio of the material, resulting in lower material cost. These pipelines are subjected to corrosions during the service life, resulting in the reduction of wall thicknesses. The prediction of the remaining strength of a corroded pipeline is required for fitness-for-purpose assessment. For the prediction of the remaining strength, different models were developed based on simplified results of analysis and/or empirical fits to limited experimental data which are expressed in terms of burst pressure. The established design codes adopt simplified design equations for the burst pressure prediction for corroded pipelines. However, the burst pressures predicted using the simplified equations are not consistent with the burst test results and results obtained from rigorous finite element (FE) analyses. Besides, the pipelines are often subjected to axial force and bending moment. The effects of the axial force and bending moment on the burst pressure are not rationally accounted. In this research, the axial forces and bending moments experience by energy pipelines are first examined considering a case of offshore pipelines. The improved burst pressure models are then developed for pipelines with and without the axial forces and bending moments. The existing models of burst pressures for deteriorated-steel pipelines are investigated to determine the contributing parameters to the burst pressures. The Folias factor and flow stress are identified as the major parameters contributing to the burst pressures of the corroded pipelines. A detailed study, based on FE analysis using Abaqus, has been carried out to develop a new method of defining the Folias factor and to develop an improved model for burst pressure prediction for a corroded pipeline. The finite element analysis is then extended to develop the new interaction rules for the pipelines subjected to multiple patches of the corrosion defects. The FE analysis is used to develop failure loci for burst pressure prediction for pipelines subjected to axial forces and bending moments. Corroded pipelines often suffer from the stress corrosion cracking (SCC) when the pipelines in corrosive environments are subjected to high tensile stresses. The SCC occurs at a stress intensity factor well below the fracture toughness of the material. The effects of the SCC and the crack propagation in the deteriorating pipelines cannot be captured using standard FE modeling techniques. It is proposed to employ fracture mechanics to determine the remaining strengths of pipelines containing corrosion defects or crack-like defects or corrosion with crack-like defects.

Download or read book Safety and Reliability Safe Societies in a Changing World written by Stein Haugen and published by CRC Press. This book was released on 2018-06-15 with total page 4379 pages. Available in PDF, EPUB and Kindle. Book excerpt: Safety and Reliability – Safe Societies in a Changing World collects the papers presented at the 28th European Safety and Reliability Conference, ESREL 2018 in Trondheim, Norway, June 17-21, 2018. The contributions cover a wide range of methodologies and application areas for safety and reliability that contribute to safe societies in a changing world. These methodologies and applications include: - foundations of risk and reliability assessment and management - mathematical methods in reliability and safety - risk assessment - risk management - system reliability - uncertainty analysis - digitalization and big data - prognostics and system health management - occupational safety - accident and incident modeling - maintenance modeling and applications - simulation for safety and reliability analysis - dynamic risk and barrier management - organizational factors and safety culture - human factors and human reliability - resilience engineering - structural reliability - natural hazards - security - economic analysis in risk management Safety and Reliability – Safe Societies in a Changing World will be invaluable to academics and professionals working in a wide range of industrial and governmental sectors: offshore oil and gas, nuclear engineering, aeronautics and aerospace, marine transport and engineering, railways, road transport, automotive engineering, civil engineering, critical infrastructures, electrical and electronic engineering, energy production and distribution, environmental engineering, information technology and telecommunications, insurance and finance, manufacturing, marine transport, mechanical engineering, security and protection, and policy making.

Download or read book Field Guide for Investigating Internal Corrosion of Pipelines written by Richard Eckert and published by Nace International. This book was released on 2003 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Principles of Forensic Engineering Applied to Industrial Accidents written by Luca Fiorentini and published by John Wiley & Sons. This book was released on 2018-11-21 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: An introductory text on the investigation of industrial accidents Forensic engineering should be seen as a rigorous approach to the discovery of root causes that lead to an accident or near-miss. The approach should be suitable to identify both the immediate causes as well as the underlying factors that affected, amplified, or modified the events in terms of consequences, evolution, dynamics, etc., as well as the contribution of an eventual "human error". This book is a concise and introductory volume to the forensic engineering discipline which helps the reader to recognize the link among those important, very specialized aspects of the same problem in the global strategy of learning from accidents (or near-misses). The reader will benefit from a single point of access to this very large, technical literature that can be only correctly understood with the right terms, definitions, and links in mind. Keywords: Presents simple (real) cases, as well as giving an overview of more complex ones, each of them investigated within the same framework; Gives the readers the bibliography to access more in-depth specific aspects; Offers an overview of the most commonly used methodologies and techniques to investigate accidents, including the evidence that should be collected to define the cause, dynamics and responsibilities of an industrial accident, as well as the most appropriate methods to collect and preserve the evidence through an appropriate chain of security. Principles of Forensic Engineering Applied to Industrial Accidents is essential reading for researchers and practitioners in forensic engineering, as well as graduate students in forensic engineering departments and other professionals.

Download or read book Assessment of Soil Corrosion in Underground Pipelines Via Statistical Inference written by Ayako Yajima and published by . This book was released on 2015 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the oil industry, underground pipelines are the most preferred means of transporting a large amount of liquid product. However, a considerable number of unforeseen incidents due to corrosion failure are reported each year. Since corrosion in underground pipelines is caused by physicochemical interactions between the material (steel pipeline) and the environment (soil), the assessment of soil as a corrosive environment is indispensable. Because of the complex characteristics of soil as a corrosion precursor influencing the dissolution process, soil cannot be explained fully by conventional semi-empirical methodologies defined in controlled settings. The uncertainties inherited from the dynamic and heterogeneous underground environment should be considered.Therefore, this work presents the unification of direct assessment of soil and in-line inspection (ILI) with a probabilistic model to categorize soil corrosion. To pursue this task, we employed a model-based clustering analysis via Gaussian mixture models. The analysis was performed on data collected from southeastern Mexico. The clustering approach helps to prioritize areas to be inspected in terms of underground conditions and can improve repair decision making beyond what is offered by current assessment methodologies. This study also addresses two important issues related to in-situ data: missing data and truncated data. The typical approaches for treating missing data utilized in civil engineering are ad hoc methods. However, these conventional approaches may cause several critical problems such as biased estimates, artificially reduced variance, and loss of statistical power. Therefore, this study presents a variant of EM algorithms called Informative EM (IEM) to perform clustering analysis without filling in missing values prior to the analysis. This model-based method introduces additional cluster-specific Bernoulli parameters to exploit the nonuniformity of the frequency of missing values across clusters.In-line inspection tools (ILI) are commonly used for pipeline defect detection and characterization with advanced technologies such as magnetic flux leakage (MFL) and ultrasonic tools (UT). Each technology has its limitation for minimum detectable defect size. As a result, the data measured by different technologies are difficult to compare under the same modeling framework. In the present study, this problem will be addressed, considering two datasets measured by MFL and UT. Moreover, a truncated generalized exponential (TGE) distribution is introduced to describe the observed data. The non-informative Jeffreys' prior is used to establish the Bayesian updating algorithm, and the Markov chain Monte Carlo (MCMC) method is adopted to estimate the posterior distribution of model.