Improving and Expanding Guided Wave Ultrasonics as an Assessment Option

2008 ◽  
Author(s):  
Robert W. Smith ◽  
Zach Barrett
Keyword(s):  
Subject Matter ◽  
Collaborative Research ◽  
Hazardous Materials ◽  
Guided Wave ◽  
Subject Matter Experts ◽  
Direct Assessment ◽  
Development Technology ◽  
Integrity Management ◽  
External Corrosion ◽  
Pipeline Safety

The Pipeline and Hazardous Materials Safety Administration (PHMSA), the pipeline industry and standards developing organizations (SDOs) are collaborating to improve the effectiveness and expand the application of Guided Wave Ultrasonics (GWUT). This paper will illustrate how these initiatives through integrity management (IM) regulation, collaborative research and development, technology demonstrations and consultation with subject matter experts (SME) are driving these improvements. These efforts are integrating GWUT technology with External Corrosion Direct Assessment (ECDA) and Pipeline Safety IM protocols and supporting higher confidence inspection of cased crossings. Previous to these initiatives only In-Line Inspection, Pressure Testing and Direct Assessment provided assessment options for the pipeline industry.

A New Probabilistic Methodology for Undertaking External Corrosion Direct Assessment

2006 ◽  
Author(s):  
Andrew Francis ◽  
Marcus McCallum ◽  
Menno T. Van Os ◽  
Piet van Mastrigt
Keyword(s):  
Surface Characteristics ◽  
Survey Techniques ◽  
Direct Assessment ◽  
Ground Survey ◽  
Pressure Test ◽  
Integrity Management ◽  
Corrosion Defects ◽  
Low Probability ◽  
External Corrosion ◽  
Pipeline Safety

External Corrosion Direct Assessment (ECDA) has now become acknowledged, by the Office of Pipeline Safety (OPS) in North America, as a viable alternative to both in-line inspection (ILI) and the hydrostatic pressure test for the purpose of managing the integrity of high pressure pipelines. Accordingly an ECDA standard is now in existence. The essence of ECDA is to use indirect above ground survey techniques to locate the presence of coating and corrosion defects and then to investigate some of the indications directly by making excavations. However, one of the problems of above ground survey techniques is that they do not locate all defects and are susceptible to false indication. This means that the defects will not be present at all indications and that some defects will be missed. In view of the limitations of above ground survey techniques the ECDA standard requires that at least two complimentary survey techniques should be used. The selected survey techniques will depend on the nature of a particular ‘ECDA segment’, taking account of the surface characteristics. However, in many situations the surveys will include a coating survey and a corrosion survey. In general the outcome from these two surveys will be NH locations at which just the coating survey gives an indication, NC locations at which just the corrosion survey gives an indication and NHC locations at which both surveys give an indication. This paper presents a new probabilistic methodology for estimating the distributions of the actual numbers of coating and corrosion defects, taking account of the outcomes of the surveys and the probabilities of detection and false indication of both techniques. The method also shows how the probabilities of detection and false indication are updated depending on what is found during the excavations and the distributions of the numbers of remaining corrosion and coating defects are subsequently modified. Based on a prescribed repair criterion the analysis is used to determine the probability that at least one remaining corrosion defect will exceed the repair criteria. As excavations are sequentially performed the probability naturally reduces. The attainment of an acceptably low probability is used as a trigger to terminate the excavation programme. A detailed description of the development of the method is given in this paper and the application is illustrated through a simple numerical example. A description of how the method is used to build a Direct Assessment module for a pipeline integrity management system is described in an accompanying paper.

Application of In-Line Inspection and Failure Data to Reduce Subjectivity of Risk Model Scores for Uninspected Pipelines

2018 ◽  
Author(s):  
Yannick Beauregard ◽  
Aaron Woo ◽  
Terry Huang
Keyword(s):  
Subject Matter ◽  
Risk Model ◽  
Subject Matter Experts ◽  
Assessment Data ◽  
Risk Models ◽  
Direct Assessment ◽  
Failure Data ◽  
Likelihood Model ◽  
External Corrosion ◽  
Integrity Assessments

Pipeline risk models are used to prioritize integrity assessments and mitigative actions to achieve acceptable levels of risk. Some of these models rely on scores associated with parameters known or thought to contribute to a particular threat. For pipelines without in-line inspection (ILI) or direct assessment data, scores are often estimated by subject matter experts and as a result, are highly subjective. This paper describes a methodology for reducing the subjectivity of risk model scores by quantitatively deriving the scores based on ILI and failure data. This method is applied to determine pipeline coating and soil interaction scores in an external corrosion likelihood model for uninspected pipelines. Insights are drawn from the new scores as well as from a comparison with scores developed by subject matter experts.

An External Corrosion Direct Assessment Module for a Pipeline Integrity Management System

2006 ◽  
Author(s):  
Menno T. van Os ◽  
Piet van Mastrigt ◽  
Andrew Francis
Keyword(s):  
Management System ◽  
Structural Reliability ◽  
Individual Performance ◽  
Corrosion Activity ◽  
Time Saving ◽  
Survey Techniques ◽  
Direct Assessment ◽  
Integrity Management ◽  
External Corrosion ◽  
The Individual

A significant part of the high pressure gas transport system of Gasunie cannot be examined by in-line inspection techniques. To ensure safe operation of these pipelines, an External Corrosion Direct Assessment (ECDA) module for PIMSLIDER (a pipeline integrity management system) is currently under development. The functional specifications of this module are based on NACE RP0502-2002, a recommended practice for ECDA. In addition to this, a new probabilistic methodology has been adopted, to take account for uncertainties associated with ECDA and to quantify the contributions from aboveground surveys and excavations to the integrity of a pipeline. This methodology, which is based on Structural Reliability Analysis (SRA) and Bayesian updating techniques, is presented in more detail in paper IPC2006-10092 of this conference. The DA module of PIMSLIDER enables computerized storage, retrieval and processing of all appropriate pipeline data and therefore guarantees highly accurate, reproducible and time saving integrity analyses of the Gasunie grid. Another important function of this system is the ability to use the complete database of all pipelines to pre-assess the integrity of a particular pipeline. This automated retrieval of data from pipelines with similar characteristics and/or environmental conditions results in a substantial increase of accessible data and enables Gasunie to improve the reliability of applied statistics throughout the process. As a consequence, the overall cost of inspections and excavations can be greatly reduced. In the Pre-Assessment phase, the DA module assists the integrity manager in gathering and analyzing data necessary to determine the current condition of a pipeline. After collection and visualization of the available data, the user can identify suitable ECDA regions. Furthermore, the gathered data are used to construct prior distributions of parameters relevant to the SRA model, such as the number and size of corrosion defects and pipeline-related parameters. In the Indirect Inspections step, the DA module allows the user to store and analyze the data from aboveground surveys, in order to identify and define the severity of coating faults and areas at which corrosion activity may occur. The probabilistic methodology accounts for the individual performance of each applied survey technique in terms of missed defects and false indications, in general a major source of uncertainty in ECDA. In the Direct Examinations phase, excavations are carried out to collect data to assess possible corrosion activity. Subsequently, the ECDA module uses this information to update, among other things, the parameters concerning the performance of survey techniques, the number of defects and the corrosion rate. As a result, updated failure frequencies are calculated for each ECDA-region (after each excavation if required), which are then used by the DA module to advise the integrity manager if additional mitigating activities are necessary, or by defining a reassessment interval.

Using Ultrasound to Gauge Pipeline Internal Corrosion With Coating for ICDA

2006 ◽  
Author(s):  
Qingshan Feng ◽  
Zupei Yang
Keyword(s):  
Test Time ◽  
Thickness Gauge ◽  
Internal Corrosion ◽  
Direct Assessment ◽  
Metal Thickness ◽  
Integrity Management ◽  
External Corrosion ◽  
Key Steps ◽  
Thickness Measurements ◽  
Non Destructive

Internal corrosion direct assessment (ICDA) for pipeline enhances the abilities to assess internal corrosion in pipeline and is based on the principle that corrosion is most likely where water first accumulates. ICDA employs the same four-step process as all other direct assessment methods. The important step is direct examinations: the pipeline is excavated and examined at locations prioritized to have the highest likelihood of corrosion. A variety of inservice non-destructive examination processes are available to pipeline operators to inspect for internal corrosion. Manual assessment of internal corrosion is considered more challenging than normal external corrosion assessments since the corrosion feature is not visible and must be interpreted by the ultrasonic response, but in the past ultrasonic test need always remove the coating and then measure on the surface of bare pipe, which brings the measurement point of the pipe body more risk because of weaker quality of patch coating. Recently, advances in the design of ultrasonic corrosion thickness gauges utilizing dual element transducers have made it possible to take accurate metal thickness measurements while coatings need not to be removed. This feature is often referred to as echo-to-echo thickness measurements. Using the ultrasound thickness gauge to measure pipeline internal corrosion while external coatings need not to be removed can keep the integrity of coating, make pipeline operating and monitoring more economical and improve inspection activities to estimate corrosion in pipelines for ICDA. Gauge equipment requirement, Measurement procedures and Accuracy were validated in laboratory. How to arrange the gauge locations, interval test time and data treatment and analysis also are the key steps of ICDA for integrity management.

Direct Assessment (DA) White Paper

2006 ◽  
Author(s):  
Robert W. Smith ◽  
Zach Barrett
Keyword(s):  
Hazardous Materials ◽  
White Paper ◽  
The Public ◽  
High Profile ◽  
Direct Assessment ◽  
Current State ◽  
Public Expectation ◽  
Integrity Management ◽  
Assessment Techniques ◽  
Pipeline Failures

The U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration (PHMSA) has drafted a direct assessment (DA) white paper to summarize the current state of direct assessment activities and practice. Several industry organizations, associations and operating companies have subsequently added content to this white paper improving the accuracy and updating the current state of direct assessment in the pipeline industry. This white paper includes information on DA standards development, drivers, current efforts to further develop DA and an overview of the path forward. Several recent high profile pipeline failures drove the public expectation that pipeline operators understand and improve the integrity of their pipelines. PHMSA has promulgated regulations to require this improved understanding and management of pipeline integrity. During the preparation of the new integrity management requirements, it was recognized that some gas transmission pipelines could not be inspected using then-available assessment techniques, pressure testing and in-line inspection. As a result, PHMSA along with the industry developed and codified several processes for assessing these lines. These processes, which utilized proven tools as part of assessment processes, are collectively called DA.

Pre-Assessment is Key to Success for Direct Assessment in Integrity Management Programs

2004 ◽  
Author(s):  
Alberto Valdes ◽  
Richard McNealy
Keyword(s):  
Assessment Method ◽  
Management Program ◽  
Gas Pipeline ◽  
Assessment Process ◽  
Practical Consideration ◽  
Direct Examination ◽  
Effective Utilization ◽  
Direct Assessment ◽  
Integrity Management ◽  
Pipeline Safety

Direct Assessment is allowed under the new Gas Pipeline Integrity Management Rules published by the Office of Pipeline Safety as an assessment method subject to specific applicability restrictions, direct examination criteria and restrictions to re-inspection intervals. The final developed costs for implementing direct assessment is largely dependent upon the extent of direct examination that in turn is a function of the pipeline condition and actual threats discovered and validated. Effective utilization of Direct Assessment within an Integrity Management Program is dependent upon the recognition of the value inherent in the Pre-Assessment Stage of the Direct Assessment Process as defined by the Rule, in which, threats are predicted, applicability confirmed and as a result of data and risk analysis, it is possible to estimate the condition of the pipeline to determine if the use of Direct Assessment is a practical consideration as well as permitted under the Gas Pipeline Integrity Management Rule.

KOC’s Integrity Management Program for Non-Piggable Pipelines: A Case Study

2010 ◽  
Author(s):  
Ashish Khera ◽  
Abdul Wahab Al-Mithin ◽  
James E. Marr ◽  
Shabbir T. Safri ◽  
Saleh Al-Sulaiman
Keyword(s):  
Risk Analysis ◽  
Systematic Evaluation ◽  
Pipeline System ◽  
Pipeline Network ◽  
Integrity Assessment ◽  
Direct Assessment ◽  
Integrity Management ◽  
Management Techniques ◽  
External Corrosion

More than half of the world’s oil and gas pipelines are classified as non-piggable. Pipeline operators are becoming aware there are increased business and legislative pressures to ensure that appropriate integrity management techniques are developed, implemented and monitored for the safe and reliable operation of their pipeline asset. The Kuwait Oil Company (KOC) has an ongoing “Total Pipeline Integrity Management System (TPIMS)” program encompassing their entire pipeline network. In the development of this program it became apparent that not all existing integrity management techniques could be utilized or applied to each pipeline within the system. KOC, upon the completion of a risk assessment analysis, simply separated the pipelines into two categories consisting of piggable and non-piggable lines. The risk analysis indicated KOC’s pipeline network contains more than 200 non-piggable pipelines, representing more than 60% of their entire pipeline system. These non-piggable pipelines were to be assessed by utilizing External Corrosion Direct Assessment (ECDA) for the threat of external corrosion. Following the risk analysis, a baseline external corrosion integrity assessment was completed for each pipeline. The four-step, iterative External Corrosion Direct Assessment (ECDA) process requires the integration of data from available line histories, multiple indirect field surveys, direct examination and the subsequent post assessment of the documented results. This case study will describe the available correlation results following the four steps of the DA process for specific non-piggable lines. The results of the DA program will assist KOC in the systematic evaluation of each individual non-piggable pipeline within their system.

Pipelines Stability under Extreme Hydrodynamic Conditions

2014 ◽  
Vol 635-637 ◽  
pp. 451-456 ◽  
Author(s):  
Liudmila Muravyeva ◽  
Nikolai Vatin
Keyword(s):  
Risk Assessment ◽  
Subject Matter ◽  
Management Practice ◽  
Seismic Loads ◽  
Subject Matter Experts ◽  
Hazard Management ◽  
The Subject ◽  
Soil Destruction ◽  
Difficult Terrain ◽  
Pipeline Safety

At the current level of technical development of subsea pipeline systems a probability of their damage during construction and operation due to various causes may not be excluded.In the regions of high seismic activity the soil destruction may occur in the weak layers forming seabed deformations. Hazard management practice has advanced in recent years, due to several factors: global pipeline expansion in areas of difficult terrain (tectonic/seismicity; permafrost area, landslides) coupled with a greater understanding of the prevalence of hazard.Formal risk assessment is relatively immature in most industries, including pipelining. A better solution is to establish guidelines of essential ingredients necessary in any pipeline risk assessment. Critical would be identified and it would be left to the operator subject matter experts to detail those elements.This article focuses on the problem of imposing special (seismic) loads; the subject matter of the article also includes the issues of the marine pipeline safety (risk) evaluation.

Complete Integrity Assessment of a Non-Piggable Multi-Diameter Cross Country Pipeline in a Network Shared by Multiple Electrically Continuous Parallel Pipelines

2021 ◽  
Author(s):  
Amit Mishra ◽  
Saurabh Vats ◽  
Carlos A. Palacios T. ◽  
Himanshu Joshi ◽  
Ishan Khurana
Keyword(s):  
Stress Corrosion ◽  
Stress Corrosion Cracking ◽  
Accurate Data ◽  
Internal Corrosion ◽  
Integrity Assessment ◽  
Direct Assessment ◽  
Integrity Management ◽  
The Subject ◽  
Cross Country ◽  
External Corrosion

Abstract A complete Pipeline Integrity Management System is the need of the hour. Apart from keeping in mind the enormous environment concerns in this rapidly dwindling era of hydrocarbons, a successful pipeline owner always strives to profitably operate their precious assets. To operate a pipeline efficiently, a plan is required to maintain its health and increase the remaining life. Various types of pipelines pose various problems which the owner needs to resolve systematically and with a well-ordered approach. A similar challenge was faced by a refinery in India. The refinery has a design capacity to process 15 MMTPA of crude per annum. The imports and exports are carried out through the local Port Trust which is one of the deepest inner harbour on the west coast. Multiple pipelines run to and from the refinery and the port trust (approximate distance — 10 km). The subject pipeline in question currently transports Mixed Xylene (MX) from refinery to port. The pipeline has a diversified operating history with various other products being transferred in the past. However, the pipeline is used very scarcely. The problem posed by the subject pipeline was similar to what many other cross-country pipelines face — the pipeline was not piggable. Five (5) other parallel pipelines share the same right-of-way, all of which are piggable and have their integrity assessment performed via Intelligent Pigging on a planned basis. There was also a concern about collecting the most accurate data since the pipeline had not undergone an integrity assessment since its commissioning in 2001. However, it was yearly pressure tested to ensure integrity of the pipeline. Parallel pipelines pose a bigger challenge for obtaining accurate data for a particular pipeline amongst them. Keeping all this in mind, a complete integrity management was planned for the MX pipeline and thus concluded on performing a turnkey Direct Assessment (DA) program. The DA program included Internal Corrosion Direct Assessment (ICDA) to assess and manage the threats of internal corrosion, External Corrosion Direct Assessment (ECDA) for external corrosion threats and Stress Corrosion Cracking Direct Assessment (SCCDA) for determining susceptibility towards the threat of stress corrosion cracking on the pipeline. Utilization of latest technologies helped in adapting and overcoming the multiple problems faced by legacy technologies especially in difficult ROW conditions and complex pipeline networks, such as the MX pipeline. This paper provides an insight into how an operator can combine latest available technologies and deploy it in unison with the complete integrity management plan.

A Robust Approach to Pipeline Integrity Management Using Direct Assessment Based on Structural Reliability Analysis

2004 ◽  
Author(s):  
Marcus McCallum ◽  
Andrew Francis ◽  
Tim Illson ◽  
Mark McQueen ◽  
Mike Scott ◽  
...  
Keyword(s):  
Reliability Analysis ◽  
Structural Reliability ◽  
Voltage Gradient ◽  
Pipeline System ◽  
Pipe Failure ◽  
Internal Corrosion ◽  
Direct Assessment ◽  
Structural Reliability Analysis ◽  
Integrity Management ◽  
External Corrosion

Approximately 1450 km (900 miles) of a 4020-km (2500 mile) natural gas pipeline system operated by Crosstex Energy Service L.P in Texas are subject to the Texas Railroad Commission’s (TRRC) integrity management rules. Consequently, in preparation for the construction of an extensive and robust integrity management program, Crosstex commissioned Advantica to assist in the development and application of a pilot study on a 13.4 km (8.3 mile) section of a 14” pipeline. The purpose of the study, which is based on Structural Reliability Analysis (SRA), was to compare the level of integrity that could be inferred from the use of Direct Assessment (DA) techniques with the level that could be inferred from ILI results. Based on a preliminary assessment of available data, the study identified both external and internal corrosion as potential threats to integrity. SRA was used in conjunction with ‘Bayesian Updating’ to determine the probability of pipe failure due to external corrosion, taking account of results from above-ground measurements and a number of bell-hole excavations. The above-ground survey techniques utilized included Close Interval Survey (CIS) and Direct Current Voltage Gradient (DCVG). A similar approach was adopted to address the threat due to internal corrosion, but hydraulic modelling was substituted for the above-ground measurements. A third study based on SRA was used to determine the combined probability of failure due to both internal and external corrosion taking account of ILI results. The outcome of the analyses demonstrated that the level of integrity that could be inferred from the use of Crosstex’ DA methodology was similar to that which could be inferred from the use of ILI. The results were presented to the TRRC for review and approval. This paper gives a detailed description of the SRA based methodology that was employed by Crosstex and presents the results that clearly demonstrate the comparability of ILI and DA for the purpose of integrity management.

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