State of the Art Assessment of Composite Systems Used to Repair Transmission Pipelines

2006 ◽  
Author(s):  
Chris Alexander ◽  
Bob Francini
Keyword(s):  
Composite Materials ◽  
Third Party ◽  
Composite Repair ◽  
Critical Elements ◽  
Research Organizations ◽  
Repair Systems ◽  
Long Term Performance ◽  
Term Performance ◽  
Transmission Pipelines

For the past decade there has been relatively wide acceptance in using composite materials to repair damaged gas and liquid transmission pipelines. There have been numerous independent research programs performed by pipeline companies, research organizations, and manufacturers that have contributed to the acceptance of composites as a legitimate repair material. Additionally, insights have been gained by both pipeline operators and composite repair manufacturers during field installations. ASME has also responded by adding sections to both the ASME B31.4 and B31.8 pipeline codes, as well as currently developing a repair standard for non-metallic composite repair systems by the Post Construction Committee. Stress Engineering Services, Inc. and Kiefner & Associates, Inc. have been integrally involved in assessing the repair of pipeline systems, with the former having been involved in performing full-scale testing and analysis on most of the major U.S.-based composite repair systems. The purpose of this paper is to provide for the pipeline industry a third-party evaluation of composite repair systems and information that is needed to properly evaluate how composite materials should be used to repair high pressure pipelines. The contents of the paper will include discussions on what critical elements should be evaluated for each composite system, items of caution and concern, and the importance of evaluation to ensure safe long-term performance.

Advanced Insights on Composite Repairs

2012 ◽  
Author(s):  
Chris Alexander ◽  
Jim Souza
Keyword(s):  
Composite Materials ◽  
Test Sample ◽  
Repair System ◽  
Strain Gages ◽  
Composite Repair ◽  
Pressure Cycling ◽  
Repair Systems ◽  
Long Term Performance ◽  
Term Performance

In response to inquiries from pipeline operators regarding the long-term performance of composite materials, manufacturers have performed additional tests to evaluate the performance of their composite repair systems. Insights were gained through these additional tests that demonstrated the long-term worthiness of the composite system. Of particular importance were two types of tests. The first involved the application of strain gages between layers of the composite repair system that was used to reinforce a corroded pipe test sample. As the sample was pressurized the strain gages permitted a comparison between the measured values and design stresses per the ASME PCC-2 design code. The second series of tests involved pressure cycling a 75% corroded sample to failure. In addition to the inter-layer strain measurements, the pressure cycling provides an important insight regarding the long-term performance of the composite repair. This paper addresses how the ASME PCC-2 Code, along with additional well-designed tests, can be used to design a composite repair system to ensure that it adequately reinforces a given defect. As composite materials are being used to repair pipeline anomalies beyond the corrosion-only defects, it is essential that pipeline operators utilize a systematic approach for ensuring the long-term performance of composite repair systems.

Advanced Techniques for Establishing Long-Term Performance of Composite Repair Systems

2014 ◽  
Author(s):  
Chris Alexander
Keyword(s):  
The United States ◽  
Operating Conditions ◽  
Repair System ◽  
Composite Repair ◽  
Design Life ◽  
Repair Systems ◽  
Long Term Performance ◽  
Term Performance ◽  
Composite Repairs

Although composite materials are used to repair and reinforce a variety of anomalies in high pressure transmission gas and liquid pipelines, there continues to be widespread debate regarding what constitutes a long-term composite repair. The United States regulations require that composite repairs must be able to permanently restore the serviceability of the repaired pipeline, while in contrast the Canadian regulations take a more prescriptive approach by integrating the ASME PCC-2 and ISO 24817 composite repair standards along with a requirement for establishing a 50-year design life. In this paper the author provides a framework for what should be considered in qualifying a composite repair system for long-term performance by focusing on the critical technical aspects associated with a sound composite repair. The presentation includes a discussion on establishing an appropriate composite design stress using the existing standards, using full-scale testing to ensure that stresses in the repair do not exceed the designated composite design stresses, and guidance for operators in how to properly integrate their pipeline operating conditions to establish a design life. By implementing the recommendations presented in this paper, operators will be equipped with a resource for objectively evaluating the composite repair systems used to repair their pipeline systems.

Strain-Based Design Methods for Composite Repair Systems

2008 ◽  
Author(s):  
Chris Alexander
Keyword(s):  
Finite Element ◽  
Composite Materials ◽  
Design Method ◽  
Design Methods ◽  
Strain Gages ◽  
Composite Repair ◽  
Reinforced Steel ◽  
Long Term Performance ◽  
Term Performance

Composite materials are commonly used to repair corroded and mechanically-damaged pipelines. Most of these repairs are made on straight sections of pipe. However, from time to time repairs on complex geometries such as elbows, tees, and field bends are required. Conventional design methods for determining the amount of required composite materials are not conducive for these types of repairs. Over the past several years, the author has developed a methodology for assessing the level of reinforcement provided by composite materials to damaged pipelines using finite element methods. Instead of stress as the design basis metric, the method employs a strain-based design criteria that is ideally-suited for evaluating the level of reinforcement provided to non-standard pipe geometries. The finite element work has been validated using experimental methods that employed strain gages placed beneath the composite repair to quantify the level of reinforcement provided by the repair. This paper provides a detailed description of the strain-based design method along with appropriate design margins for both the reinforced steel and long-term performance of the composite materials.

Long-Term Duration of Composite Repair Systems for Pipeline Defects

2021 ◽  
Vol 1035 ◽  
pp. 870-877
Author(s):  
Lian Xun Ming ◽  
Deng Zun Yao ◽  
Bin Chen ◽  
Zhen Heng Teng ◽  
Lin Wang
Keyword(s):  
Composite Materials ◽  
Water Immersion ◽  
Prediction Equation ◽  
Field Application ◽  
Composite Repair ◽  
Micro Cracks ◽  
Aging Properties ◽  
Repair Systems ◽  
Hydrolysis Of

Composite repair systems of buried pipeline will be affected by moisture and other factors due to anti-corrosion and construction problems. These environmental factors will reduce the service life of the composite system. In this paper, the performance of composite and interface between composite and steel under the action of water were studied. It was found that the formation of micro-cracks on the surface of composite materials and the hydrolysis of epoxy resin were the important reasons for the Performance degradation. Moreover, the aging properties of composite materials and their interfaces under water immersion were analyzed by residual strength theory, and the life prediction equation of composite materials and interfaces were obtained, which can be useful to the field application of composite repair systems.

Repair of Dents Subjected to Cyclic Pressure Service Using Composite Materials

2010 ◽  
Author(s):  
Chris Alexander ◽  
Julian Bedoya
Keyword(s):  
Composite Materials ◽  
Extensive Study ◽  
Life Extension ◽  
Composite Repair ◽  
The Past ◽  
Extensive Evaluation ◽  
Research Organizations ◽  
Repair Systems ◽  
Primary Focus ◽  
Girth Welds

For the better part of the past 15 years composite materials have been used to repair corrosion in high pressure gas and liquid transmission pipelines. This method of repair is widely accepted throughout the pipeline industry because of the extensive evaluation efforts performed by composite repair manufacturers, operators, and research organizations. Pipeline damage comes in different forms, one of which involves dents that include plain dents, dents in girth welds and dents in seam welds. An extensive study has been performed over the past several years involving multiple composite manufacturers who installed their repair systems on the above mentioned dent types. The primary focus of the current study was to evaluate the level of reinforcement provided by composite materials in repairing dented pipelines. The test samples were pressure cycled to failure to determine the level of life extension provided by the composite materials relative to a set of unrepaired test samples. Several of the repaired dents in the study did not fail even after 250,000 pressure cycles were applied at a range of 72% SMYS. The results of this study clearly demonstrate the significant potential that composite repair systems have, when properly designed and installed, to restore the integrity of damaged pipelines to ensure long-term service.

The Behaviours of Cementitious Materials in Long Term Storage and Disposal: An Overview of Results of the IAEA Coordinated Research Project

2009 ◽  
Vol 1193 ◽  
Author(s):  
Zoran Drace ◽  
Michael I. Ojovan
Keyword(s):  
Cementitious Materials ◽  
Research Project ◽  
Main Research ◽  
Long Term Storage ◽  
Research Organizations ◽  
And Performance ◽  
Long Term Performance ◽  
Term Performance ◽  
Cementitious Systems

AbstractCementitious materials are widely used in waste management systems with different aims and requirements for long term performance. Both conventional and novel cementitious materials are used to create reliable immobilising elements for safe storage and disposal of wastes. The barrier elements as well as interactions envisaged between various components are important to ultimately ensure the overall safety of a storage/disposal system. The behaviour and performance of cementitious materials including waste package components, wasteform and backfilling were analysed within the IAEA Coordinated Research Project which involved 26 research organizations from 21 Member States MS). The paper presents briefly the main research outcomes for conventional cementitious systems; novel materials and technologies; testing and waste acceptance criteria; and modelling long term behaviour.

Developing Stress Intensification Factors for Composite Repair Systems Used to Repair Damaged Pipe

2010 ◽  
Author(s):  
Chris Alexander
Keyword(s):  
Composite Materials ◽  
Extensive Study ◽  
Life Extension ◽  
Composite Repair ◽  
The Past ◽  
Extensive Evaluation ◽  
Research Organizations ◽  
Piping Systems ◽  
Repair Systems ◽  
Girth Welds

For the better part of the past 15 years composite materials have been used to repair corrosion in high pressure gas and liquid transmission pipelines. This method of repair is widely accepted throughout the pipeline industry because of the extensive evaluation efforts performed by composite repair manufacturers, operators, and research organizations. Pipeline damage comes in different forms, one of which involves dents that include plain dents, dents in girth welds and seam welds. An extensive study has been performed over the past several years involving multiple composite manufacturers that installed their repair systems on the above mentioned dent types. The test samples were pressure cycled to failure to determine the level of life extension provided by the composite materials over a set of unrepaired test samples. Several of the repaired dents in the study did not fail even after 250,000 pressure cycles had been applied at a range of 72% SMYS. The primary purpose of this paper is to present details on how Stress Intensification Factors were derived using the empirically-generated data. The results of this study clearly demonstrate the significant potential that composite repair systems have, when properly designed and installed, to restore the integrity of damaged pipelines and piping systems to ensure long-term service.

Fine Particle Mass Monitoring with Low-Cost Sensors: Corrections and Long-Term Performance Evaluation

2019 ◽  
Author(s):  
Carl Malings ◽  
Rebecca Tanzer ◽  
Aliaksei Hauryliuk ◽  
Provat K. Saha ◽  
Allen L. Robinson ◽  
...  
Keyword(s):  
Performance Evaluation ◽  
Fine Particle ◽  
Low Cost ◽  
Particle Mass ◽  
Long Term Performance ◽  
Term Performance
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