An Estimate of the Market Potential for Corrosion Protection, Prevention, and Monitoring Systems in Ships

2009 ◽  
Vol 25 (04) ◽  
pp. 214-220
Author(s):  
Saurav Dhiman ◽  
Biplab Datta

There was a sudden increase in the number of ship accidents in the early 1990s. The primary reason for these accidents was a combination of local corrosion, fatigue cracking, and operational damage. This paper establishes the need for corrosion protection and monitoring systems for marine vessels. An attempt has been made to estimate the market potential for such systems in the near future.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Michio Kumagai ◽  
Richard D. Robarts ◽  
Yasuaki Aota

AbstractAn autonomous underwater vehicle (AUV) was deployed in Lake Biwa from 2000 to 2012. In December 2009, ebullition of turbid water was first found in the deepest area (> 90 m) of the North Basin. Follow-up investigations in April and December 2010 and January 2012 confirmed the existence of benthic vents similar to the vents observed in other deep lakes. Importantly, vent numbers per unit travel distance in Lake Biwa dramatically increased from only two vents (0.37 vents km−1) in December 2009 to 54 vents (5.28 vents km−1) in January 2012, which could be related to recent tectonic activity in Japan, e.g., the M9.1 Tohoku earthquake in March 2011 and slow earthquakes along the Nankai Trough from 2006 to 2018. Continuous back-up investigations from 2014 to 2019 revealed additional benthic vents in the same area. The sudden increase in benthic vent activity (liquid and gaseous ebullitions) have significant potential to alter lake biogeochemistry and, ultimately, degrade Japan’s major drinking water source and may be a harbinger of major crustal change in the near future.


2021 ◽  
Vol 16 (4) ◽  
pp. 121-137
Author(s):  
Michele Fabio Granata

The case-study of a steel bowstring bridge set in a marine environment and highly damaged by corrosion is presented. The bridge was built in 2004 and was repainted for corrosion protection in 2010. Despite the recent construction and the maintenance interventions, many structural elements like hangers are highly damaged by corrosion with decreasing performance in terms of serviceability and ultimate limit states. A deep investigation was carried out in order to assess the bridge and to establish the necessary retrofit actions to be carried out in the near future. In-situ tests reveal the reduced performance of the original steel in terms of strength and corrosion protection, together with the inefficiency of the successive maintenance interventions. The paper presents assessment of the bridge and retrofit measures, including replacement of the hangers and galvanization through thermal spray coating technology, in order to increase its service life. The results of the investigations and the intervention measures are outlined and discussed.


Author(s):  
Ankang Cheng ◽  
Nian-Zhong Chen

Subsea structures such as pipelines are vulnerable to environment-assisted crackings (EACs). As a type of EAC, corrosion fatigue (CF) is almost inevitable. For such a process, stress corrosion (SC) and hydrogen-assisted cracking (HAC) are the two mainly driving mechanisms. And it was further pointed out that slip dissolution (SD) and hydrogen embrittlement (HE) should be responsible for SC and HAC respectively. Based on such a fact, a two-component physical model for estimating the CF crack propagation rate was proposed. The proposed model was built in a frame of fracture mechanics integrated with a dissolution model for C-Mn steel and a newly established model by the authors accounting for the influence from HE upon crack propagation. The overall CF crack propagation rate is the aggregate of the two rates predicted by the two sub-individual models, and then the crack propagation time is calculated accordingly. The model has been proven to be capable of capturing the features of HE influenced fatigue cracking behaviour as well as taking mechanical factors such as the loading frequency and stress ratio into account by comparison with the experimental data of X42 and X65 pipeline steels.


Author(s):  
James Frith ◽  
Robert Frith

After operating for a number of years, a high temperature rotary ore cooler suffered cracking. The cracks grew through the shell wall resulting in leakage of water from the water bath into the ore. Under the extreme temperature, the risk of water dissociation into hydrogen and subsequent explosion was of substantial concern and instigated the investigation in to the root cause of the cracking which was deduced to be driven by high thermally induced stresses. The root cause for the thermally induced stressing was found to be related to a design flaw that was not immediately obvious. The investigation outcome was a recommendation to change the design to eliminate the high localized stresses which were believed to be the driving force behind the corrosion fatigue crack propagation. This paper presents the investigation approach which included advanced thermal and stress analysis and reports on the general design principle that should be adopted to avoid thermal stress induced corrosion fatigue cracking under high temperature operation.


2011 ◽  
Vol 300 (5) ◽  
pp. G709-G715 ◽  
Author(s):  
Jonathan A. Fallowfield

Detailed analysis of the cellular and molecular mechanisms that mediate liver fibrosis has provided a framework for therapeutic approaches to prevent, slow down, or even reverse fibrosis and cirrhosis. A pivotal event in the development of liver fibrosis is the activation of quiescent hepatic stellate cells (HSCs) to scar-forming myofibroblast-like cells. Consequently, HSCs and the factors that regulate HSC activation, proliferation, and function represent important antifibrotic targets. Drugs currently licensed in the US and Europe for other indications target HSC-related components of the fibrotic cascade. Their deployment in the near future looks likely. Ultimately, treatment strategies for liver fibrosis may vary on an individual basis according to etiology, risk of fibrosis progression, and the prevailing pathogenic milieu, meaning that a multiagent approach could be required. The field continues to develop rapidly and starts to identify exciting potential targets in proof-of-concept preclinical studies. Despite this, no antifibrotics are currently licensed for use in humans. With epidemiological predictions for the future prevalence of viral, obesity-related, and alcohol-related cirrhosis painting an increasingly gloomy picture, and a shortfall in donors for liver transplantation, the clinical urgency for new therapies is high. There is growing interest from stakeholders keen to exploit the market potential for antifibrotics. However, the design of future trials for agents in the developmental pipeline will depend on strategies that enable equal patient stratification, techniques to reliably monitor changes in fibrosis over time, and the definition of clinically meaningful end points.


2011 ◽  
Vol 275 ◽  
pp. 101-104 ◽  
Author(s):  
Graham Clark ◽  
Ung Hing Tiong ◽  
Aditya Jaya

Aircraft joints feature prominently in aircraft structural degradation. Fatigue cracking and corrosion damage can reduce joint strength and degrade service life. Corrosion management can include use of paints and sealants and, increasingly, the application of Corrosion Inhibiting Compounds (CICs) which retard corrosion, by penetrating into crevices and cracks, and displacing water. A combination of coatings and CIC use can provide effective corrosion protection, but both interact - in different ways - with structural performance and overall system durability. This paper discusses the interaction between these two corrosion protection measures and fatigue performance of joints. The first issue relates to a reduction in the fatigue life of mechanically-fastened joints after application of CICs (or other lubricants) The lubricating properties of the CICs reduce the friction at the faying surface, which may change the load transfer characteristics of the joint. The paper discusses results from a test program assessing the fatigue life and failure mode of riveted lap joints; the results show a marked reduction in fatigue life for joints containing CICs, and the paper discusses the changes which may be responsible for the reduction. The second issue discussed is the degradation of protective coatings in service. Joints are key locations for coating cracking and failure, since areas such as sheet ends and fastener heads, where displacements are concentrated, will produce concentrated strain in coatings. So far, however, the potential influence of aircraft loading on coating degradation prognostics has received little attention. The paper discusses the role of joint displacement in service as a factor contributing to early degradation of aircraft coatings, and argues that this local strain effect, and indeed structural loading history, needs to be considered in predicting and assessing rates of coating degradation. It describes initial analyses of displacements in aircraft joints, to identify the levels of coating strain and the roles and relative contributions of the various deflections in the joints. The results indicate the potential for very large strains in coatings.


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