A Study of Crack Interaction Criteria

Author(s):  
Colin Scott

Cracks in close proximity may interact and lead to leaks or ruptures at pressures well below the predicted failure pressures of the individual cracks. Several industry organizations and standards, including CEPA, ASME, API, and British Standards provide guidance on the treatment of potentially interacting cracks. This guidance tends to be very conservative. This paper is a study of crack interaction, including a discussion of industry guidance, a critical review of failure pressure models, and a review of results of laboratory hydro-testing of pipe sections containing either in-service flaws or simulated flaws. In some cases the industry guidance and current failure pressure models provide inconsistent predictions, and this leads to uncertainty in the assessments used in routine crack management programs. The results of the hydro-testing are discussed in the context of both types of predictions. Understanding and predicting these interactions is important in maintaining an effective and efficient crack management program. The paper is aimed at engineers involved in integrity assessments and integrity management system process improvement.

Author(s):  
Alex J. Baumgard ◽  
Tara L. Coultish ◽  
Gerry W. Ferris

Over the last 15 years, BGC Engineering Inc. has developed and implemented a geohazards Integrity Management Program (IMP) with 12 major pipeline operators (consisting of gas and oil pipelines and of both gathering and transmission systems). Over this time, the program has been applied to the assessment of approximately 13,500 individual hydrotechnical and geotechnical geohazard sites spanning approximately 63,000 km of operating pipelines in Canada and the USA. Hydrotechnical (watercourse) and geotechnical (slope) hazards are the primary types of geohazards that have directly contributed to pipeline failures in Canada. As with all IMPs, the core objectives of a geohazard management system are to ensure a proactive approach that is repeatable and defensible. In order to meet these objectives, the program allows for varying levels of intensity of inspection and a recommended timescale for completion of actions to manage the identified geohazards in accordance with the degree of hazard that the site poses to the pipeline. In this way, the sites are managed in a proactive manner while remaining flexible to accommodate the most current conditions at each site. This paper will provide a background to the key components of the program related specifically to existing operating pipeline systems, present pertinent statistics on the occurrence of various types of geohazards based on the large dataset of inspections, and discuss some of the lessons learned in the form of program results and program challenges from implementing a geohazard integrity management system for a dozen operators with different ages of systems, complexity of pipeline networks, and in varied geographic settings.


Author(s):  
Menno T. van Os ◽  
Piet van Mastrigt ◽  
Andrew Francis

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.


Author(s):  
Lawrence Ator ◽  
Minh Ho

The National Energy Board of Canada (NEB), a federal energy regulator, has implemented a management system audit program as a tool to verify compliance with its predominantly goal-oriented Onshore Pipeline Regulations, 1999 (OPR) [1]. The OPR allow individual companies to choose the most effective way to manage their pipeline systems. The audit program is based on expected elements that the NEB believes are necessary to meet the goals of the OPR. This paper will explain why these audits and expected elements are necessary and describe how goal-oriented regulations will enhance pipeline safety. The audits conducted to date have identified several challenges that the NEB and pipeline companies face in pursuit of the goal of safe pipelines; these will be described and possible solutions will be proposed. The overall objective of the paper is to explain the benefits of using a management system approach to direct a company’s pipeline integrity management program and what is required of companies to meet the expectations of the NEB.


Author(s):  
Honglong Zheng ◽  
Muyang Ai ◽  
Lijian Zhou ◽  
Mingfei Li ◽  
Ting Wang ◽  
...  

As a preventative management mode, integrity management which is significantly effective is now applicable in modern industry. Based on the successful application of integrity management for the pipeline, managers expect an extension of the integrity management program for the oil and gas stations such as pumping stations, so as to make the best arrangement of resources and guarantee the safety of station facilities. The differences between station integrity management system in China and abroad are analyzed. It is claimed that the oil and gas station integrity management is more difficult and complicated in China. An integrity management program is developed for the oil and gas stations in China. The authors summarily introduce the station integrity management framework, and determine the processes and elements of management. For the main parts of the stations are plenty of facilities, the authors attempt to carry out the management on each category of facilities in particular. According to the characteristics and working status, field facilities can be classified into three categories: static facilities, dynamic facilities, and electrical instruments. For all these facilities, integrity management approach consists of five steps: data collection, risk assessment, integrity assessment, repair & maintenance, and performance evaluation. Station integrity management system comprises five aspects: system documents, standards & specifications, supporting technologies, management platforms and applications. This paper should be considered as a reference for the oil and gas station integrity managers in the future.


Author(s):  
M. Robb Isaac ◽  
Saleh Al-Sulaiman ◽  
Monty R. Martin ◽  
Sandeep Sharma

In early 2005, Kuwait Oil Company (KOC) initiated a Total Pipeline Integrity Management System (TPIMS) implementation in order to carry out a major integrity assessment of its operating facilities, equipment, buried plant piping and pipeline network and to establish a continuing integrity management program. KOC Transit System is a complex infrastructure consisting of over three hundred pipelines, thousands of wellhead flow lines, and consumer and offshore lines for which there was a significant loss of data when the facilities were destroyed during a military invasion in 1990. An initial pipeline system assessment identified issues and actions regarding condition of the pipelines, corridors, requirements on in-line inspection (ILI), documentation, RISK assessment, status of international code compliance, and overall state of the system. Following recommendations from that initial assessment led to the development of a long term strategy; the execution of which required the implementation of a comprehensive integrity management program. This case study discusses the results obtained after five years of implementation of TPIMS at KOC. It will demonstrate some of the complex components involved in managing the integrity of the Transit System that have been made possible through the implementation of the system. The general concept and structure of TPIMS will be described, and how it deals with the complexity of the KOC pipeline system. The system made it possible to integrate and manage data from various sources, by conducting integrity assessment using ILI, Direct Assessment and hydrostatic testing, as well as structure a comprehensive RISK & Decision Support mechanism. This is one of the world’s first implementations of this magnitude which encompasses such a wide range of services and variables; all being managed in a single environment and utilized by a multitude of users in different areas at KOC. The biggest challenge in a project of this scope is data management. Examples will be shown of the integration structure to illustrate the benefits of using a single comprehensive and versatile platform to manage system requirements; ultimately providing system reliability and improving overall operational efficiency.


Author(s):  
Reena Sahney ◽  
Mike Reed ◽  
Darren Skibinsky

The Canadian Energy Pipeline Association (CEPA) is a voluntary, non-profit industry association representing major Canadian transmission pipeline companies. With the advent of changes in both CSA Z6621 as well as the National Energy Board Onshore Pipeline Regulations (OPR)2, the membership determined a Recommended Practice regarding a Management Systems Approach for Facilities Integrity was needed. As such, the Pipeline Integrity Working Group (PIWG) within CEPA formed a task group to support the initiative. The outlined approach was intended to have two main philosophical underpinnings: it must comprehensively support safe pipeline system operations and it must provide a practical mechanism for implementing a management systems approach for Facilities Iintegrity. The main challenge in developing a framework for a Facilities Integrity Management System lies in the broad range of equipment and system types that the management system must encompass. That is, equipment, in the context of Facilities Integrity Management, must encompass not only station equipment (such as rotating equipment, valves, meters etc.,) but also categories such as high pressure station piping and fuel lines. Further, there was the recognition that Operators already have an array of tools, processes and techniques in place to manage their various equipment and systems. In light of these observations, the Recommended Practice describes a framework that uses major equipment types as a key differentiator. This is an approach that can be easily aligned with existing corporate computerized maintenance management systems (CMMS) such as SAP™ or Maximo™. Once the equipment categorization has been established, the Recommended Practice then provides guidance regarding the specific requirements that should be addressed for each equipment category based on the framework in CSA Z662-11 Annex N. Specific suggestions are provided in the areas of: alignment with corporate goals and objectives, scope, definitions, performance metrics, risk assessments, competency of personnel, change management as well as documentation. The approach also maximizes the opportunity to leverage existing systems and processes to the extent possible. Overall the Recommended Practice should provide operators with a practical way to achieve a greater degree of rigor and alignment of facilities integrity management while ensuring detailed study and analysis is focused in the most appropriate areas.


Author(s):  
Bruce Hansen ◽  
Jeff Wiese ◽  
Robert Brown

In 2000 and 2002, the US Department of Transportation’s Office of Pipeline Safety (OPS) published new regulations requiring integrity management programs for hazardous liquid pipeline operators. OPS had four fundamental objectives: 1) to increase the level of integrity assessments (i.e., in-line inspection or pressure testing) for pipelines that can affect high consequence areas; 2) to improve operator integrity management systems; 3) to improve government oversight of operator integrity management programs; and 4) to improve public assurance in pipeline safety. At the core of this new rule is a set of management-based requirements (referred to as “Program Elements” in the rule) that are fundamentally different from the existing, largely prescriptive pipeline safety requirements. The evaluation of operator compliance with these requirements requires the examination of management and analytical processes-aspects of operator’s business that are not reviewed in standard OPS compliance inspections. OPS realized a fundamentally different approach to oversight was needed to assure operators are developing and implementing effective integrity management programs. This paper describes the comprehensive changes to the OPS inspection program that were developed to perform integrity management inspections. OPS completed the initial integrity management inspection of all large hazardous liquid pipeline operators in early 2004, and is making progress in reviewing the programs of smaller liquid operators. During this initial year OPS gained substantial knowledge about the state of hazardous liquid pipeline operator integrity management programs. At a high level, OPS learned that operators generally understand what portions of their pipeline systems can affect high consequence areas, and are making the appropriate plans and progress in conducting integrity assessments for these areas. However, the development of effective management and analytical processes, and quality data and information to support these processes takes time. While most operators appear to be headed in the right direction, fundamental changes to management systems require time. OPS recognizes this situation and has developed an inspection and enforcement approach that not only assures compliance with the rule requirements, but also fosters continuous improvement in operator integrity management programs. This paper describes the lessons learned from the initial inspections, and OPS expectations for future integrity management program development. Finally, the intial year of integrity management inspections provided some valuable insights about how to perform these new type of inspections and improve external communication. This paper also addresses what OPS learned about its inspection program, and how this program is being positioned to support on-going inspections of hazardous liquid operator integrity management programs.


Author(s):  
Aleksandar Tomic ◽  
Shahani Kariyawasam

Risk Assessment is an integral part of an Integrity Management Program (IMP), and it is generally the first step in most IMPs. Risk is of the product of two variables, the likelihood of failure and the consequence of failure, where failure is defined as a loss of containment event. Hence, it is necessary to calculate both variables in order to accurately model risk. To assess risk, criterion need to be established and the actual risk needs to be compared to the criterion in order to determine the acceptability of risk. Currently, most industry risk assessment models are qualitative risk models, where consequence is generally characterized by class, relative population measures, or some other relative measure. While this may be adequate for some relative risk ranking purposes, it is generally not accurate in representing the true consequences and the arbitrary nature leads to overly conservative or overly un-conservative results. Conversely, Quantitative Risk Assessment (QRA) models take into account the effect of the thermal radiation due to ignited pipeline rupture and evaluate the consequence on the surrounding human population. Such a consequence model is dependent on the pipeline properties (i.e. diameter and MOP) and the structure properties (i.e. precise locations and types of structures). The overall risk is then represented by two specific, well defined measures: Individual Risk (IR) and Societal Risk (SR). The goal of this paper is to perform a critical review of IR and SR acceptability criteria that are widely available and widely used, and outline the criteria (and the approach) adapted by TransCanada Pipelines. Worldwide, there are several different standards that define the criteria for evaluating IR and SR, particularly some countries with higher population densities around pipelines (e.g. UK and Netherlands). These IR and SR criteria have been compared in a hypothetical case study, to determine the most appropriate method in terms of the assumptions for calculating risks, the criteria, and how the actual risks compares to the criteria. The outcome of this study was the adoption of a defendable process for calculating SR, along with the associated criterion.


Author(s):  
Bushra Waheed ◽  
Brodie Couch ◽  
Gouri Bhuyan ◽  
Hassan Iqbal ◽  
Eddie Lee

Integrity Management Program (IMP) is a systematic and documented program for assuring asset integrity throughout the full life cycle of an asset. To ensure safe and reliable operation, the British Columbia Oil and Gas Commission (Commission) has been requiring its licensed pipeline operators through its regulations to develop and implement pipeline integrity management programs (IMPs) in accordance with Canadian Industry Standard CSA Z662. The auditing process, the collated results and findings from the IMP audit years (2011–15) were published in IPC 2016-64161[1]. Since 2016, the Commission has enhanced its IMP compliance assurance process, and aligned it with the management system approach using Deming’s model of plan-do-check-act (PDCA) for IMP components and incorporated a lifecycle approach that spans the entire lifecycle of a pipeline system from planning to abandonment. In addition, the Commission has adopted a multi-criteria decision-making approach when prioritizing which operators to audit. This method utilizes weighted rank approach and takes into account multiple factors, such as, previous IMP audit results, pipeline length and product, class location, incident frequency, and asset age. Through collaborative efforts with the University of British Columbia (Okanagan), an innovative risk based audit tool — Integrity Management Program Audit and Knowledge Tool (IMPAKT) has been developed to help evaluate the compliance of operators’ IMP in terms of the management system approach and its associated risk. This tool conducts three-dimensional analysis of IMP performance using the failure mode effect analysis (FMEA) technique and allows the Commission to generate a risk profile for each IMP component to determine which components are most critical, requiring immediate attention. The final audit results are presented as a Risk Priority Number (RPN), which is a product of severity, occurrence and action. An effective integrity management program requires a strong safety culture, therefore, safety culture aspects are incorporated into the risk based auditing tool, IMPAKT. This risk based evaluation process also allows the Commission to develop a compliance benchmark to make comparison between different operators’ IMP results for continuous performance improvement. This paper presents the innovative approach developed and implemented by the Commission for the IMP compliance oversight (auditing) process and implication of such changes.


2014 ◽  
Vol 26 (8) ◽  
pp. 1377-1385 ◽  
Author(s):  
Tilly Eichler ◽  
Jochen René Thyrian ◽  
Daniel Fredrich ◽  
Leonore Köhler ◽  
Diana Wucherer ◽  
...  

ABSTRACTBackground:A computerized Intervention-Management-System (IMS) has been developed and implemented to facilitate dementia care management. IMS is a rule-based expert decision support system that matches individual patient characteristics to a computerized knowledge base. One of the most important functionalities of IMS is to support the compilation of the individual intervention plan by systematically identifying unmet needs and suggesting the corresponding specific interventions for recommendation to the general practitioner (GP). The present analysis aimed to determine if the implementation of IMS improves the identification of unmet needs and the recommendation of adequate specific interventions. In addition, the feasibility and acceptability of the IMS were evaluated.Methods:Delphi-MV is an on-going GP-based, cluster-randomized, controlled intervention trial to implement and evaluate a collaborative dementia care management program for community-dwelling PWDs and their caregivers. IMS was developed and implemented over the course of the DelpHi-trial. The identified unmet needs and the interventions that were recommended to the GP before and after the implementation of IMS were compared. To evaluate the feasibility and acceptability of the IMS, a survey was conducted among the current users of IMS.Results and Conclusions:After the implementation of IMS, the number of specific interventions recommended to the GP increased by 85%. Our findings provide evidence that IMS improves the systematic identification of unmet needs and the subsequent recommendation of interventions to address these needs. The users evaluated IMS as very helpful and would like to use it for their future work. However, the usability could be further improved.


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