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Corrosion is the degradation of metals by chemical or electrochemical reaction with loss of their physical properties in specific areas or overall. Every year in industrialised countries the losses due to corrosion are enormous — roughly about 3.5 to 4.2% of a country's GDP, and running into billions of dollars. A significant part of these losses can be avoided by putting into practice existing corrosion control measures in a systematic manner.

Corrosion monitoring techniques fall broadly into two categories: those which provide simple numeric data for control purposes, and those which offer a spectrum of information for diagnostic purposes. Corrosion monitoring can be carried out directly at locations susceptible to corrosion, or indirectly under conditions simulating susceptible but inaccessible points. The interpretation of the data can reflect the purpose of monitoring at the particular location. A consistent form of presentation, and comparative tabulation including statistical analysis can greatly facilitate correlation and trend spotting. Broad spectrum techniques may give an early indication of new problems. An effective internal corrosion monitoring programme can make a major contribution towards the control of plant operating costs.

Many Indonesian operators generally have a tendency to keep their aircraft in service up to or even beyond their economic design goal life (EDGL). The problem that should be solved by the operators is how to operate those ageing aircraft safely and economically. The combination of fatigue and corrosion phenomena needs vigorously corrective action to meet airworthiness requirements, though it increases costs in maintenance. Since corrosion is a never‐ending problem, the aviation community such as designer, manufacturer, operator and the regulatory authority has an obligation to be more concerned and proactive in ensuring continuous airworthiness of the ageing aircraft. Aims to assess issues on corrosion prevention and control activities conducted by Indonesian operators, discusses all the facts and possible corrective actions and provides recommendations to maintain and ensure safe operation of ageing aircraft by controlling and preventing corrosion as well as metal fatigue.

To study and compare the inhibition effects of eco‐friendly inhibitors of sodium silicate and 1‐hydroxyethylidene 1,1 diphosphonic acid (HEDP) in corrosion control and prevention of soft water discolouration (red water) in carbon steel pipelines.

Electrochemical impedance and Tafel polarization measurements were used to study corrosion inhibition properties. The experiments were carried out under different concentration ratios of inhibitors. Different hydrodynamic conditions were applied to simulate pipeline fluid flow. Scanning electron microscopy (SEM) and EDAX analysis were used for surface studies.

It was observed that corrosion inhibitor combinations under static conditions showed synergistic effects at low concentrations. The inhibition efficiency and synergistic behaviours of inhibitors were enhanced as the electrolyte turbulence was increased. In addition, the inhibitor concentration value required to reach maximum inhibition decreased. It was found that at 20 ppm sodium silicate and 5 ppm HEDP, co‐inhibition efficiencies increased significantly to more than 90 per cent and the corrosion rate decreased far below 1 mpy as the electrode rotational speed was increased. Surface studies using SEM revealed the formation of a compact and uniform film of co‐inhibitors.

The results of this paper can be used for the development of effective, non‐toxic and economically attractive corrosion inhibitor formulations for soft water transmission pipelines.

The observed synergistic behaviour can be due to the incorporation of the silicate gel‐like network through organic phosphorous bonds. The hydrodynamic condition of the electrolyte leads to enhancement of inhibition efficiency, which indicates that the corrosion inhibition was mass transfer controlled.

The aim was to study the effect of an electromagnetic treatment used on corrosion control of carbon steel in cooling systems.

The aim was to assess the performance of an electromagnetic treatment used on corrosion control of carbon steel in cooling water systems.

The main conclusion is that the electromagnetic system cannot induce a direct effect on the corrosion rates. The use of chemical corrosion inhibitors cannot be suggested.

The optimized industrial use of water is an objective of unquestionable importance, as water is a finite resource. The use of efficient corrosion control on water cooling systems permits the reduction of the water volume required. Consequently, a social benefit can be associated with the improvement of corrosion control technologies.

The development of alternative corrosion control technologies, such as the use of physical treatments, has been considered as a promising tool. In this work, a consistent assessment of the results achieved on a full-scale system, without using chemical corrosion inhibitors, is presented.

This paper aims to study the controlled release and synergistic effect of water-soluble polyvinyl alcohol (PVA) on phosphate corrosion inhibitor at the interface of thermal insulation cotton/carbon steel.

This study was carried out using a coating method, scanning electron microscopy, energy dispersive spectroscopy and AC impedance.

The single-phase phosphate particles were coated/adsorbed on the PVA film, which was formed on the fiber surface of corrosion inhibitor/PVA-impregnated rock wool sample. On the surface of Q235 steel, an effective protective film was formed by the corrosion inhibitor with partially dissolved PVA that can significantly increase the polarization resistance of corrosion reaction, and reduce the capacitive reactance of electric double layer. The rock wool impregnated with the phosphate corrosion inhibitor and 1.5 per cent PVA showed obvious controlled release and inhibition synergism.

The rock wool impregnated with the phosphate corrosion inhibitor and 1.5 per cent PVA showed the following advantages: the adsorption and release quantities of the corrosion inhibitor increased by 3.3 and 2.9 times, respectively; the release-adsorption equilibrium time increased from 2 to 6 h; and the corrosion inhibition efficiency increased from 61.55 per cent to 94.6 per cent.

To analyze the different approaches used to estimate the cost of corrosion and understand the limitations so as to have proper appropriation in future appraisals.

Four well‐known approaches to analysis of cost of corrosion viz., the Uhlig method, the Hoar method, NBS‐BCL input/output method and net present value method have been considered in great detail and the impact of these approaches on corrosion economy in different countries has been highlighted.

Uhlig method of estimating corrosion cost always gives a conservative estimate of the direct cost of corrosion. The direct cost of corrosion, as estimated by the Hoar method, is found to be somewhat higher than is the estimate made using the Uhlig method, as shown by Shibata of Japan. The NBS‐BCL method of input/output analysis, though apparently more scientific, is subject ultimately to uncertainties in quantifying the capital cost and intermediate output. The net present value method appears to be more realistic than do other approaches as it enables a life cycle costing of each structure/facility to be made and arrives at the most cost‐effective corrosion control method. Even though all the above four approaches enable an estimation of direct cost of corrosion, there is no standard approach to assess the indirect cost of corrosion.

In a developing economy, each and every industry has to go for systematic corrosion auditing in order to identify and adopt the most appropriate corrosion control measures and effect considerable savings. This paper would be of immense use in that regard.

Considers briefly the history of corrosion in metallic aircraft. Summarizes the different types of corrosion which affect aircraft and the methods for monitoring and measuring this corrosion. Presents an alternative approach called “controlled search peening” where the induced surface compressive stresses stretch and yield the outer material surface and induce visible blistering and flaking at the surface, indicating the existence of exfoliation corrosion.

This paper aims to report the best practices of deicer corrosion control adopted by the Washington State Department of Transportation (WSDOT) to preserve the performance, reliability and value of its highway maintenance equipment assets.

To enable quantitative analyses, data were collected from a site visit to WSDOT, as well as from a survey of maintenance practitioners from various transportation agencies. The direct costs related to equipment corrosion aggravated by the exposure to roadway deicers were analyzed, along with the direct benefits of mitigating such corrosion, using WSDOT as a case study. In addition, the same preliminary cost benefit analysis was conducted for an “average” Department of Transportation in a northern climate.

Both cases show a highly favorable benefit-to-cost ratio for enhanced investment in controlling the risk of deicer corrosion.

It has not yet been possible to confirm this compelling argument because the analysis is partly based on assumptions instead of fully based on actual data.

This work highlights the need to collect the relevant data such that future analysis and sensitivity analysis can be substantiated with actual data on costs and benefits. It concludes with a few suggestions for implementation.

Many components in highway maintenance equipment fleet are at the risk of metallic corrosion, which is exacerbated in service environments where roadway deicers have been applied. This work lays the foundation for future research into this important issue.

This paper seeks to describe the adoption and implementation of a cost‐effective gas pipeline corrosion monitoring and control procedure for use in natural gas infrastructural facilities in sub‐Saharan Africa.

The incidence and severity of pipeline corrosion in a major gas production facility were monitored using a combination of instrumented field survey (potential measurements, line currents and soil resistivity measurements) and microscopic evaluation (OM and SEM) techniques. Portable field survey equipment with appropriate circuitry, contactors and sensors for potential, line current and soil resistivity measurements were used to make the field measurements. The equipment was standardized and calibrated for use in the service environment. The field survey data were superimposed on common plots in order to obtain clearer and complementary information on possible corrosion hotspots and damage locations along the submerged pipelines. Metallographic examination of the samples collected from the field was carried out to establish the type of corrosion attacks and mode of failure of the pipeline material.

It was established that a combination of corrosion‐related damage occurred as a result of localized attack over time. The investigation procedure was cost‐effective and can be used to determine which pipeline structures are protected and to gauge with a high degree of precision the integrity of the submerged pipeline.

In the future, the procedure could be fully automated for routine on‐line/on‐site monitoring of gas pipelines in a sour‐gas environment.

The paper presents a useful database for the selection and/or design of corrosion‐resistant materials for use in sour‐gas environments and data for a comprehensive corrosion monitoring and control program in the peculiar service environment of sub‐Saharan Africa, for improved performance, productivity, personnel safety and reduced operating costs.

The information is useful to on‐site engineers and operators of gas‐production facilities, particularly in sub‐Saharan Africa, for designing and implementing cost‐effective corrosion monitoring and control programs.