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Despite improvements in tank cars since their invention in 1870, a major problem has always remained—the problem of corrosion and contamination control. Although aluminium and stainless‐steel cars seem to offer the ideal solution to this problem in some applications, the initial cost of such tank cars makes their utilisation impracticable for most users. It has been estimated that less than 2% of the 174,000 tank cars now in service in the U.S.A. are so constructed. However, close to 10%, or more than 17,000 interiors or tank cars at present in use, are treated with protective coatings or linings designed to ensure adequate protection for the cars and the products they carry. Customer demand for high standards of product purity is continuing to raise this figure at a rapid rate. Because of this trend towards the use of more and better protective linings, the ever‐increasing diversification of chemical products, and the once‐again rising use of railroad tank cars, Metalweld Inc., of Philadelphia, have recently conducted an extensive study of the problems encountered in the protection of tank‐car interiors and exteriors and the effect of such protection on the purity of the products carried. The results of the research indicated that, in practically every problem situation, protection of car and product can be achieved by one of the many protective coating systems available to industry today.

Geigy Co. Ltd. Stand 75. Diversified application of benzotriazole as a corrosion inhibitor specifically for copper and its alloys is the main theme of Geigy's stand.

Glassflake filled polyester and epoxy resin lining and coating systems have been developed and used in the fight against corrosion during the last 15 years. Similarly, sophisticated silica and carbon filled glass cloth reinforced systems have been developed for rapid site installation to tanks and floors. These linings have many technical and cost advantages over conventional materials and are now gaining wide acceptance by the plant engineer and specifier.

Multilayer composite liner structures are the primary structural form of hydraulic tunnels. However, the bearing mechanism of multilayer composite liners has not been investigated thoroughly. Many existing design schemes do not properly achieve a balance between structural safety, anti-seepage capacity, and cost effectiveness. Thus, a new composite liner structure type and its theoretical model was proposed.

A novel hydraulic tunnel composite liner structure with a polyurea spray coating interlayer was proposed in this study. A theoretical model based on the state-space method was developed and verified using FEM models and existing theoretical models. Parametric analysis was conducted based on the theoretical model to investigate the influence of various variables, including interfacial shear stiffness, inner liner thickness, and outer liner elastic modulus.

It was concluded that the proposed theoretical model can be used successfully to calculate multilayer composite liner structures with high calculation efficiency. The overall deformation stiffness of the composite liner system increased with the interfacial shear stiffness. The sprayed coating interlayer significantly affects the residual force distribution between the outer and inner liners, which can also be affected by the adjustment of the thickness of the outer and inner liners. Thus, attention should be paid to these factors in the rational design of the proposed composite liner system.

With the development of China’s water conservancy projects, complex geological conditions, high surrounding rock stress, high internal and external water pressures, and other unique application scenarios have gradually increased. This places higher requirements on the bearing performance and impermeability of hydraulic tunnel lining structures. On the other hand, conventional hydraulic tunnel lining structures can hardly achieve a satisfactory balance between economy, structural safety, and impermeability. Thus, the proposed structure has the potential to be used in a wide range of applications.

From November 29 to December 2 the Empire Hall at Olympia, London, will be given over to what will probably be the world's largest display of products, processes and services for use in the prevention or limitation of corrosion. Over 120 stands will be shared by 94 exhibitors, each contributing in some way or in many ways to this cause. The extensive preview in the following pages is divided into sections. However, the grouping is general and reflects only one aspect of a company's activities. Therefore a complete examination of items is recommended.

Glassflake reinforced lining and coating systems have been under continuous development and evaluation for nearly two decades. For the last 15 years they have been extensively used and are now available in a variety of formulations to suit most corrosive environments. These systems combine abrasion and erosion with corrosion resistance in a unique way to provide cost effective protection to a wide range of plant and equipment. Because of this, these materials are gaining wide acceptance by the specifier and engineer alike, and the term F.R.P. has gained a new meaning — Flake Reinforced Plastic.

Neoprene is the name given to a synthetic elastomer based on polychloroprene. When neoprene is vulcanised, a. product having similar physical properties to cured natural rubber, but generally more abrasion‐ and chemical‐resistant, is produced. Various types of neoprene can be produced by different techniques in the manufacture of the polymer, all types having their own characteristics. This article surveys the neoprene materials used in the protective coating and lining fields—liquid and sheet neoprene, caulking compounds, putties and adhesives—and some of the practical applications to which they have been put.

Summary The variety of approaches used to combat corrosion and afford protection of structures and components are outlined. Factors governing selection so often favour combinations of traditional metal and modern polymeric coating or lining. Emphasis is placed on the vital importance of surface preparation and comprehensive specifications. In this context, the role of Specialist Painting Inspectors is outlined and their contribution to quality assurance and improved standards of workmanship is illustrated by reference to bridges, offshore platforms, telescopes and lined components. Future trends are indicated with emphasis on newer methods of surface preparation and protection.

Industrial chimneys are a great part of environmental protection in industrial countries. In recent years many of them have been used to carrying away very aggressive gases from boilers and flue gas desulphurisation (FGD) units below acid dew‐point temperature. It is opf very important to modernize the old stacks and protect them against corrosion. The proper anti‐corrosion protection of modern high stacks is also an important technical and economical problem. In this paper the mechanism of acid dew‐point corrosion, as well as construction of industrial chimneys, methods of their anti‐corrosion protection and modernisation are described.

The plant engineer anxious to protect equipment from corrosion can today choose from a variety of methods, one of which is to use elastomeric lining and coating materials designed to meet a given set of corrosive conditions. What must be known, however, in selecting the right materials and methods are not only the properties of the coatings but also their limitations. In the following, some properties and uses of linings based on elastomers are considered.