Smart Pig Defect Tolerances: Quantifying the Benefits of Standard and High Resolution Pigs

2004 ◽  
Author(s):  
Stephen Westwood ◽  
Phil Hopkins
Keyword(s):  
High Resolution ◽  
Signal Analysis ◽  
Oil And Gas ◽  
Management Plan ◽  
Major Effect ◽  
Metal Loss ◽  
Confidence Levels ◽  
Failure Assessment ◽  
Oil And Gas Pipelines ◽  
Integrity Management

Smart pigs are used as part of an integrity management plan for oil and gas pipelines to detect metal loss defects. The pigs do not measure the defects: they collect signals from on board equipment and these signals are later analysed. Signal analysis is complex; consequently, defect sizing tolerances and confidence levels can be difficult to determine and apply in practice. They have a major effect when assessing the significance of the defect, and when calculating corrosion growth rates from the results of multiple inspections over time. This paper describes how defect sizing tolerances and confidence levels are obtained by pigging companies, and compares standard and high resolution pigs. Probability theory is used by the authors to estimate the likelihood that a defect is smaller or deeper than the reported (by the pig) value for both standard and high resolution tools. The paper also shows how these tolerances can be included in defect failure assessment and the results of multiple pig runs.

Implementation of a Pipeline Integrity Management System at TIGF (France): The Added Value of the Pipeline Threats and Mitigations Module

2008 ◽  
Author(s):  
Karine Kutrowski ◽  
Rob Bos ◽  
Jean-Re´gis Piccardino ◽  
Marie Pajot
Keyword(s):  
Management System ◽  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Management Plan ◽  
Point Of View ◽  
Added Value ◽  
Specific Information ◽  
Transmission Grid ◽  
Integrity Management ◽  
Corrective Actions

On January 4th 2007 TIGF published the following invitation for tenders: “Development and Provision of a Pipeline Integrity Management System”. The project was awarded to Bureau Veritas (BV), who proposed to meet the requirements of TIGF with the Threats and Mitigations module of the PiMSlider® suite extended with some customized components. The key features of the PiMSlider® suite are: • More than only IT: a real integrity philosophy, • A simple intuitive tool to store, display and update pipeline data, • Intelligent search utilities to locate specific information about the pipeline and its surrounding, • A scalable application, with a potentially unlimited number of users, • Supervision (during and after implementation) by experienced people from the oil and gas industry. This paper first introduces TIGF and the consortium BV – ATP. It explains in a few words the PIMS philosophy captured in the PiMSlider® suite and focuses on the added value of the pipeline Threats and Mitigations module. Using this module allows the integrity analyst to: • Prioritize pipeline segments for integrity surveillance purposes, • Determine most effective corrective actions, • Assess the benefits of corrective actions by means of what-if scenarios, • Produce a qualitative threats assessment for further use in the integrity management plan, • Optimize integrity aspects from a design, maintenance and operational point of view, • Investigate the influence of different design criteria for pipeline segments. To conclude, TIGF presents the benefits of the tool for their Integrity Management department and for planning inspection and for better knowledge of their gas transmission grid.

Management of Pipeline Dents and Mechanical Damage in Gas Pipelines

2006 ◽  
Author(s):  
David J. Warman ◽  
Dennis Johnston ◽  
John D. Mackenzie ◽  
Steve Rapp ◽  
Bob Travers
Keyword(s):  
High Resolution ◽  
Magnetic Flux ◽  
Mechanical Damage ◽  
Management Plan ◽  
Magnetic Flux Leakage ◽  
Pipeline System ◽  
Channel Geometry ◽  
Channel Deformation ◽  
Integrity Management ◽  
Flux Leakage

This paper describes an approach used by Duke Energy Gas Transmission (DEGT) to manage dents and mechanical damage as part of its overall Integrity Management Plan (IMP). The approach provides guidance in the process for evaluating deformation anomalies that are detected by high resolution magnetic flux leakage (HR-MFL) and multi-channel geometry in-line inspection tools, the process to determine which deformations will be selected for excavation, the process to conduct pipeline field excavations, assessments, and repairs for pipeline integrity purposes. This approach was developed, tested and fully implemented during pipeline integrity work over a two year program involving over 1,100 miles of HR-MFL and 900 miles of geometry in-line inspection. Integration of data from high resolution ILI tools (HR-MFL and multi-channel deformation tools) was used to identify and characterize dents and mechanical damage in the pipeline system. From subsequent field assessments and correlation with ILI results, the processes were refined and field procedures developed. The new guidance provided in the 2003 edition of ASME B31.8 was used as the governing assessment criteria.

Probabilistic Fitness-for-Service Assessment of Pipeline

2012 ◽  
Author(s):  
Vlad Semiga ◽  
Aaron Dinovitzer
Keyword(s):  
Oil And Gas ◽  
Probability Of Failure ◽  
Management Program ◽  
Design Stage ◽  
Simulation Based ◽  
Oil And Gas Pipelines ◽  
Input Parameters ◽  
Assessment Approach ◽  
Integrity Management ◽  
Over Time

Fitness for service assessments of oil and gas pipelines, conducted either at the design stage or to evaluate an indentified anomaly, are generally carried out in a deterministic manner based on conservative estimates of the required input parameters. The following paper presents a probabilistic Fitness-for-Service (FFS) assessment approach which can be used in a risk based pipeline integrity management program. The probabilistic assessment utilizes an Advanced Monte Carlo simulation based approach and the fracture mechanics techniques described in BS 7910. The paper presents an overview of the basic approach and provides a demonstration of its capabilities in terms of estimating the risk of failure (or probability of failure) associated with a pipeline over time, due to the presence of a crack like flaw. The paper also discusses the sources of data and inherent assumptions used to model various input parameters required for a typical FFS analysis carried out according to BS 7910.

Self Directed Integrity Assessment of Non-Piggable Pipelines

2015 ◽  
Author(s):  
Ashish Khera ◽  
Rajesh Uprety ◽  
Bidyut B. Baniah
Keyword(s):  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Management Plan ◽  
Gas Industry ◽  
Internal Corrosion ◽  
Integrity Assessment ◽  
Regulatory Standards ◽  
The Us ◽  
Integrity Management ◽  
External Corrosion

The responsibility for managing an asset safely, efficiently and to optimize productivity lies solely with the pipeline operators. To achieve these objectives, operators are implementing comprehensive pipeline integrity management programs. These programs may be driven by a country’s pipeline regulator or in many cases may be “self-directed” by the pipeline operator especially in countries where pipeline regulators do not exist. A critical aspect of an operator’s Integrity Management Plan (IMP) is to evaluate the history, limitations and the key threats for each pipeline and accordingly select the most appropriate integrity tool. The guidelines for assessing piggable lines has been well documented but until recently there was not much awareness for assessment of non-piggable pipelines. A lot of these non-piggable pipelines transverse through high consequence areas and usually minimal historic records are available for these lines. To add to the risk factor, usually these lines also lack any baseline assessment. The US regulators, that is Office of Pipeline Safety had recognized the need for establishment of codes and standards for integrity assessment of all pipelines more than a decade ago. This led to comprehensive mandatory rules, standards and codes for the US pipeline operators to follow regardless of the line being piggable or non-piggable. In India the story has been a bit different. In the past few years, our governing body for development of self-regulatory standards for the Indian oil and gas industry that is Oil Industry Safety Directorate (OISD) recognized a need for development of a standard specifically for integrity assessment of non-piggable pipelines. The standard was formalized and accepted by the Indian Ministry of Petroleum in September 2013 as OISD 233. OISD 233 standard is based on assessing the time dependent threats of External Corrosion (EC) and Internal Corrosion (IC) through applying the non-intrusive techniques of “Direct Assessment”. The four-step, iterative DA (ECDA, ICDA and SCCDA) 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 paper presents the case study where the Indian pipeline operators took a self-initiative and implemented DA programs for prioritizing the integrity assessment of their most critical non-piggable pipelines even before the OISD 233 standard was established. The paper also looks into the relevance of the standard to the events and other case studies following the release of OISD 233.

Study on Acceptable Risk for Oil and Gas Pipelines in China

2010 ◽  
Author(s):  
Hua Zhang ◽  
Jinheng Luo ◽  
Juanli Chen ◽  
Xinwei Zhao ◽  
Guangli Zhang
Keyword(s):  
Risk Assessment ◽  
Oil And Gas ◽  
Gas Pipeline ◽  
Risk Level ◽  
Gas Pipelines ◽  
Acceptable Risk ◽  
Risk Criteria ◽  
Oil And Gas Pipelines ◽  
Integrity Management

Risk assessment is basis to put pipeline integrity management in practice and the acceptable risk level is important criteria to execute risk assessment and constitute maintenance safeguard. So it is very important to establish a rational and practicable acceptable criterion and present a specific acceptable risk level. It is just for this need that the present paper gave a review of all the available research around the acceptable risk level and analyzed various domestic and overseas standards and documentation concerning how to define the acceptable risk criteria. As a result, a criterion suitable for oil and gas pipeline was presented and recommended acceptable risk level was gave.

Quantification of Measurement Errors in the Lengths of Metal-Loss Corrosion Defects Reported by Inline Inspection Tools

2019 ◽  
Vol 141 (6) ◽  
Author(s):  
T. Siraj ◽  
W. Zhou
Keyword(s):  
Measurement Error ◽  
Measurement Errors ◽  
Logistic Model ◽  
Oil And Gas ◽  
Metal Loss ◽  
Type I ◽  
Large Set ◽  
Type Ii ◽  
Oil And Gas Pipelines ◽  
Corrosion Defects

Abstract This paper proposes a framework to quantify the measurement error associated with lengths of corrosion defects on oil and gas pipelines reported by inline inspection (ILI) tools based on a relatively large set of ILI-reported and field-measured defect data collected from different in-service pipelines in Canada. A log-logistic model is proposed to quantify the likelihood of a given ILI-reported defect being a type I defect (without clustering error) or a type II defect (with clustering error). The measurement error associated with the ILI-reported length of the defect is quantified as the average of those associated with the types I and II defects, weighted by the corresponding probabilities obtained from the log-logistic model. The implications of the proposed framework for the reliability analysis of corroded pipelines given the ILI information are investigated using a realistic pipeline example.

Managing the Threat of Selective Seam Weld Corrosion Using a State of the Art ILI System

2020 ◽  
Author(s):  
Christopher Davies ◽  
Simon Slater ◽  
Christoper De Leon
Keyword(s):  
Material Properties ◽  
Weld Zone ◽  
Evaluation Process ◽  
Management Plan ◽  
Management Approach ◽  
Metal Loss ◽  
Integrity Assessment ◽  
Seam Weld ◽  
Integrity Management ◽  
Weld Corrosion

Abstract For many years, pipeline safety regulations in the US have defined prescriptive minimum requirements for integrity management combined with a clear expectation that operators should do more than the minimum where appropriate. The regulations have also provided operators with the flexibility to take a performance based integrity management approach leveraging as much information available to manage threats effectively. One the threats that must be managed is Selective Seam Weld Corrosion (SSWC). SSWC is an environmentally assisted mechanism in which there is increased degree of metal loss in the longitudinal weld in comparison to the surrounding pipe body. An appropriate definition is linear corrosion that is deeper in the longitudinal weld zone than the surrounding pipe body. In some cases, the surrounding pipe body may have limited or no corrosion present, and in other cases the pipe body corrosion may have occurred but at a slower rate than the local corrosion in the longitudinal weld zone. Conventional responses to potential or identified threats focus on in-situ investigations, often resulting in expensive and un-planned repairs for features reported by In-line Inspection (ILI) that when assessed properly demonstrate a remnant life well into the next inspection interval. When ILI identifies metal loss indications co-located with the longitudinal seam weld, the current prescribed response is often a blanket call for remediation. Such a response may not be appropriate if an ILI system is deployed to discriminate feature types and integrity assessment is exercised leveraging a sound understanding of the pipe’s material properties. This paper describes an approach that can be taken to manage the threat of SSWC. The foundation of the approach is deployment of an appropriate ILI system incorporating an effective ILI technology, an optimized evaluation process considering the specific threat morphology, material testing and a structured dig program. The evaluation process uses the ILI data and data from the field in combination material properties data and a susceptibility analysis to classify anomalies as “Likely”, “Possible” and “Unlikely” SSWC. This is aligned with the guidance in API RP 1176 “Assessment and Management of Cracking in Pipelines” for defining an appropriate response to ILI calls. Approaching the management of SSWC in this way allows operators to define a structured response for excavation activities to verify the process and remediate features as required. By using likelihood classification the risk to pipeline integrity can be reduced by acting on the most likely SSWC features as a priority, whilst collecting the data needed to make informed decisions on where to focus resources and efforts on what is a very complicated and difficult to manage threat. The output form this work, including a future plan for managing the remaining metal loss features, can be documented in a procedure and incorporated into an existing Integrity Management Plan.

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