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The purpose of this paper is to study the cause of severe corrosion of the galvanized lightning rods in a 220 kV transformer substation, and to seek the effective corrosion inhibition measures for the hollow lightning rods.

The corrosion morphology and rust component of lightning rod was analyzed, and the corrosion process of lightning rod was researched by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), ion chromatography and electrochemical tests.

The results indicated that the outer surface of hollow lightning rod was corroded slightly; however, its inner surface suffered severe corrosion because of a long time high-humidity environment inside the tube caused by the rainwater permeation. A rust layer consisted of Fe₃O₄ and a little FeOOH was accumulated on the inner surface of the hollow lightning rod. Moreover, Fe₃O₄ rust layer worked as a large cathode area which could promote the corrosion of metal substrate further. A self-accelerating corrosion process was formed on the inner surface, making the corrosion failure of lightning rod occurred and aggravated gradually.

The corrosion of inner surface of hollow lightning rod cannot be detected easily. More attention should be paid to the corrosion inhibition of lightning rod. The key of corrosion inhibition for the hollow lightning rod was to avoid the rainwater accumulation inside tube. The research results can provide guidelines on the corrosion inhibition measures selection of lightning rod in transformer substation.

It is shown that complete derusting of structural steel is not necessary if rust converter which can convert adherent rust into a protective coating is used. The performance of the rust converter developed by the authors is described in this paper.

There are literally hundreds of publications which begin by referring to the expense incurred through the depredations of rust. Consequently the technical literature on the occurrence of rust and on its nature is voluminous and, the basic principles involved in its formation being known, it might seem nearly impossible to contribute anything fresh to the subject. However, even though the basic conditions necessary for rust formation are well known and explanations of the rusting mechanism are likely to be amended only in detail, there are considerable difficulties in applying the knowledge to individual problems where rust prevention is necessary. Some of these difficulties stem from the loose manner in which the term ‘rusted ’ is applied, others from lack of correlation between cause and effect, between the type of oxide or hydroxide found and the original factors responsible for the phenomenon, and still others through lack of a clear specification of the degree of rust prevention required, which could be permanent or temporary, continuous or intermittent, complete or partial, depending on economic rather than technical considerations. It is proposed to consider in this article the stain stage of rusting, because this is the period at which it might be possible to obtain the maximum amount of information on the rusting process.

It must be first of all asked what rust really is. The question may seem to have an obvious answer. Anybody who has had anything at all to do with iron is acquainted with the effect of rust. Nevertheless, it has to be admitted that even a number of researchers who have dedicated themselves to the subject do not have such clear ideas about it as might be assumed on the first approach. The cause of rust has always been, and still is, a subject of research and discussion, especially in the light of modern electrochemical theory which indicates to us very clearly that to attribute to rust the binomial ‘water+atmospheric oxygen’ alone is a solution which is far too simplistic. A lot of theories have been put forward in this matter, but we shall obviously not have time to study them all. According to J. N. Friend, iron which has been subjected to the combined attack of water vapour and atmospheric oxygen only corrodes quickly when carbon dioxide is present, even in small quantities.

The Presidential Address to the Liverpool Engineering Society by Mr. Farthing (the salient points of which are reproduced in this issue) has particular bearing upon lubrication and especially on young lubrication engineers. Mr. Farthing stressed the very wide field open to young engineers and the difficulties associated with training in order to cover as wide a field as may be necessary. It is usually so important to gain a wide knowledge before one can specialise and this is certainly the case with lubrication engineers. One cannot begin to fully appreciate the intricacies of a lubrication system with all its accessory components lubricating and guarding, for example, a large motive power plant or rolling mill, until one has more than a mere working knowledge of the plant itself, the duties it must perform, how it performs them and the snags that arise which might be overcome by correct lubrication. In view of the fact that lubrication systems are just as important in a textile mill as in a power station or a large brick works, the almost impossible‐to‐achieve‐range of knowledge that would simplify the work of a lubrication engineer is very obvious. Fortunately, lubricating principles apply to most cases and knowing how to apply one's knowledge from basic principles is the key to success in this difficult profession.

The corrosion of boiler drums is intimately linked to the deterioration of the protective oxide film separating the steel substrate from the boiler fluid, which often contains constituents conducive to corrosion. Various forms of corrosion occur in the boiler drums and such occurrences can be due to:

Fretting corrosion—a surface damage occurring between two closely fitting surfaces subject to slight vibrational movement—has caused trouble in machinery ever since the first closely fitting machined parts were put together. It is something different from ordinary wear or rusting of the usual chemical nature, and it is not always recognised as fretting corrosion by users of equipment in which it occurs. ‘Friction oxidation,’ ‘wear oxidation,’ ‘false brinelling,’ ‘chafing,’ ‘bleeding’ and ‘cocoa’ are some of the names that have been applied to the phenomenon. One of the results of work carried out by the Mechanical Engineering Research Laboratory of the D.S.I.R., briefly described in CORROSION TECHNOLOGY, May 1954, is that it is possible to correlate the degree of damage with such variables as total number of oscillations, load or atmospheric humidity. In the United States, too, much work has been done on fretting corrosion and ways of combating it. So that as many as possible could benefit from this research, the American Society for Testing Materials organised a Symposium in which leading experts gave their findings. The Symposium has recently been published as a booklet. Here are shortened versions of two of the papers presented.

The purpose of this paper is to study the influence of temperature on the acceleration and simulation of indoor corrosion tests and the corrosion behavior of Q235 carbon steel.

The indoor corrosion test was carried out by continuous salt spray in a salt spray chamber. Weight loss analysis, X-ray diffraction, cannon 1500 D, scanning electron microscopy and electrochemical techniques are used to analyze the results.

It was found that thickness loss of Q235 carbon steel increases with higher temperature and it can reach 0.095 mm at 50°C. Compared with the Xisha exposure test, the acceleration rate can achieve 230 times. This phenomenon indicates that decreasing the experimental temperature is beneficial to the anti-corrosion of the Q235 carbon steel. It is fascinating to find that acceleration and simulation increase with temperature simultaneously, which shows that β-FeOOH promotes the corrosion rate and α-FeOOH provides high simulation. Meanwhile, electrochemical impedance spectroscopy indicates that the resistance of the rust layer improves with temperature.

Through the study, the authors found that with the increase of temperature, the acceleration and simulation of indoor corrosion test improved, corrosion products and kinetics are the same as those in outdoor exposure test, and which means that the laboratory can achieve the long-term corrosion degree of outdoor exposure in a short time, and the similarity with outdoor exposure is high. This helps to the study of marine atmospheric corrosion, and indoor accelerated corrosion tests can largely eliminate regional differences by adjusting some environmental factors, and lay a foundation for marine atmospheric corrosion.

The effects of temperature on the acceleration and simulation of indoor corrosion tests are discussed. Through laboratory experiments, the long-term service life of Q235 carbon in the Xisha marine atmosphere can be predicted effectively.

This paper aims to investigate the reason for natural gas leakage from transmission pipelines between Linyi and Shouguang in China during sealing tests, explore the failure mechanism and provide a reference for taking reasonable measures to prevent such accidents.

Failure analysis for the steel pipe has been addressed with different methods, such as microstructure analysis, inclusion analysis, corrosion product analysis, macro- and micro-morphology analyses and bacterially catalyzed experiments.

Several bulges were observed, especially at the bottom of the steel pipe sample, with the distribution and positioning not related to the weld. The inner surface of the steel pipe was severely corroded, and the oxide scale was flaking in many places. The greatest corrosion area was identified at the bottom of the steel pipe near the gas leakage point. Severe pitting and perforation corrosion in the pipeline were observed, and the main corrosion reaction products were Fe3O4, FeO and FeS. The grain orientation distribution near the crack (coarse grains <101> and fine grains <111> at the microcrack tip) indicates that fine grains may be beneficial in hindering crack propagation.

The principal mechanism for the corrosion failure is supposed to be due to the interaction of chloride ions with the sulfate-reducing microorganisms present and the stress corrosion cracking by chloride and sulfide formed by the sulfate-reducing microorganisms.

During the latter part of the 19th century industrial processes were developed to produce adherent oxide films on steel as a means of protection against corrosion.