The Role of Composite Repair Technology in Rehabilitating Piping and Pipelines

Author(s):  
Chris Alexander

Composite materials have been used to repair high pressure pipelines and piping for the better part of 20 years. The initial aim of composite repair technology was focused on reinforcing corrosion. However, composite materials are now used to reinforce a wide array of anomalies and features including dents, mechanical damage, vintage girth and seam welds, wrinkle bends, elbows, tees, branch connections, and even cracks. In this paper the author provides an industry overview including results and insights from multiple research programs sponsored by composite repair manufacturers, pipeline operators, and the Pipeline Research Council International, Inc. Discussions will also be included regarding the important role that the ASME PCC-2 and ISO 24817 composite repair standards have in ensuring that quality control measures are in place. The ongoing focus of these efforts has been to demonstrate to industry the capabilities that composite repair systems have to provide long-term solutions for reinforcing damaged equipment.

Author(s):  
Chris Alexander ◽  
Jim Souza ◽  
Casey Whalen

For the better part of the past 20 years composite materials have been used to repair damaged piping and pressurized components in plants, refineries, and pipelines. The use of composite materials has been accompanied by comprehensive research programs focused on the development and assessment of using composite technology for restoring integrity to damaged piping and pressurized components. Of particular interest are composite repair standards such as ISO 24817 and ASME PCC-2 that provide technical guidance in how to properly design composite repair systems. The vast body of research completed to date has involved assessments at ambient conditions; however, at the present time there is significant interest in evaluating the performance of composite repair materials at elevated temperatures. This paper is focused on the topic of high temperature composite repairs and addresses the critical role of utilizing temperature-based mechanical properties to establish a composite repair design. The backbone of this effort is the development of composite performance curves that correlate change in strength as a function of temperature. A discussion on supporting full-scale pressure test results are included, along with guidance for users in how to properly design composite repair systems for applications at elevated temperatures.


2020 ◽  
Author(s):  
Dinesh Aggarwal ◽  
Richard Myers ◽  
William L. Hamilton ◽  
Tehmina Bharucha ◽  
Niamh Tumelty ◽  
...  

A review was undertaken of all genomic epidemiology studies on COVID-19 in long term care facilities (LTCF) that have been published to date. It was found that staff and residents were usually infected with identical, or near identical, SARS-CoV-2 genomes. Outbreaks usually involved one predominant lineage, and the same lineages persisted in LTCFs despite infection control measures. Outbreaks were most commonly due to single or few introductions followed by spread rather than a series of seeding events from the community into LTCFs. Sequencing of samples taken consecutively from the same cases showed persistence of the same genome sequence indicating that the sequencing technique was robust over time. When combined with local epidemiology, genomics facilitated likely transmission sources to be better characterised. Transmission between LTCFs was detected in multiple studies. The mortality rate amongst residents was high in all cases, regardless of the lineage. Bioinformatics methods were inadequate in one third of the studies reviewed, and reproducing the analyses was difficult as sequencing data were not available in many cases.


2021 ◽  
Vol 1035 ◽  
pp. 870-877
Author(s):  
Lian Xun Ming ◽  
Deng Zun Yao ◽  
Bin Chen ◽  
Zhen Heng Teng ◽  
Lin Wang

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.


Crystals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 559 ◽  
Author(s):  
Jingyu Sun ◽  
Yunhe Zhou ◽  
Yajuan Su ◽  
Sheng Li ◽  
Jingmei Dong ◽  
...  

Resveratrol (RSV) has various pharmacological effects; however, few studies have directly addressed the possible antifatigue effects of long-term endurance exercise. The clinical use of RSV is limited by its poor water solubility and extremely short plasma half-life. Solid lipid nanoparticles (SLNs) are considered as reasonable drug delivery systems to overcome some of these drawbacks and expand its applications. In this study, RSV-SLNs were successfully prepared through emulsification and low-temperature solidification. Results showed that RSV-SLN supplementation effectively enhanced endurance performance. RSV-SLN supplementation might enhance mitochondrial function by ameliorating mitochondrial quality control (QC), which was superior to RSV application. These results revealed an unexpected role of RSV-SLN compared with RSV in terms of linking nutrient deprivation to mitochondrial oxidant production through mitochondrial QC. A mitochondrion-mediated pathway was likely involved in RSV-SLN, thereby improving endurance performance. Overall, this study highlighted new possibilities for anti-physical-fatigue strategies.


1997 ◽  
Vol 4 (1) ◽  
pp. 49-53 ◽  
Author(s):  
ABM Wilmink ◽  
C S F F Hubbard ◽  
C R G Quick ◽  
A B M Wilmink

Objectives— To assess quality and variability in measurements of the infrarenal aortic diameter by ultrasound, and to recommend quality control measures to improve consistency in measurements of the infrarenal aortic diameter (IAD) in a long running screening programme. Setting— An aneurysm screening programme in Huntingdon. Methods— Quality of the ultrasound image was subjectively assessed by each ultrasonographer. Quality of the measurements was assessed by analysing the frequency of measurements that were outside the normal variability of the estimated true diameter. The interobserver variability was measured by analysing repeated measurements of the IAD in the same patient by two ultrasonographers, using the same scanner. The variability between different scanners was measured by analysing repeat measurements of the IAD in the same patient by the same ultrasonographer, using two scanners. The intraobserver variability was estimated by analysing all patients with three consecutive measurements of the IAD, carried out by the same ultrasonographer. Results— Although the subjective assessment of the quality of the ultrasound image of the aorta varied, there were no statistically significant differences in the likelihood of obtaining measurements outside the limits of agreement between the ultrasonographers. The interobserver, intraobserver, and between scanner variability of ultrasound measurements of the IAD were all around 6 mm. Conclusion— The variability in ultrasound measurements of aortic diameters is acceptable for clinical decision making, and the interobserver variability is very similar to the long term intraobserver variability. Quality control measures are suggested to maintain long term consistency of ultrasound measurements of the IAD.


2001 ◽  
Vol 7 (S2) ◽  
pp. 470-471
Author(s):  
Robin H Cross

The economic importance of animal hides and skins as the source material for the natural leather industry is significant world-wide, and in some countries of the developing world the livelihood of a large proportion of the population depends upon it. Consequently, it is understandable that anything affecting the quality of the source material and the finished product has major economic, industrial and sociological significance. It is also inevitable that a product that is so widely-used in many ways by most of the population will become an important source of evidence in forensic investigations.Quality control procedures in the leather industry involve monitoring the progress of the hides and skins from the growth stages of the animal, through the slaughter, storage, transportation, curing, tanning and finishing processes, to the sale and distribution of the finished product. There are many factors during these stages that can affect quality of finished leather, amongst the most important of which are mechanical and parasite damage during growth, biodeterioration and mechanical damage between slaughter and curing, mechanical, heat and chemical damage during curing, tanning and finishing.


Author(s):  
Chris Alexander

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.


Author(s):  
Chris Alexander ◽  
Jim Souza

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.


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