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In chemical plants, corrosion is present to some extent in practically all electrical installations. Some of this corrosion is of a limited nature and relatively harmless. In other cases a more suitable material or a better appreciation of design factors would avoid severe cases which call for costly shutdowns. Numerous metals and alloys are available for electrical installations; all have advantages and disadvantages. This information, together with pertinent design factors, is the key to trouble‐free electrical units.

The purpose of this present work is to investigate how different parameters of the blast cleaning process affect properties and quality of brass parts surface. It aims to study the following process variables: particle abrasive shape: (spherical (S) and angular (G) shot), particle abrasive size (S170, G40 and G50) and the impact velocity (40 m/s, 60 m/s and 80 m/s).

An experimental approach based on three testing methods is used to quantify the analysis of particulate contaminants on substrates surfaces. These methods are: SEM, BSEM and EDXA plots from SEM imaging.

The results obtained clearly show that the particle embedment decreases with decreasing of the size of angular abrasive. An increase in the embedment could be noted as impact velocity increased. It was also found that the angular abrasives have delivered a contamination level higher than that delivered by spherical abrasives. Furthermore, it was demonstrated that the abrasive debris nature embedded in the treated surfaces is the iron. The coupling of this debris with the base metal (copper) in the presence of wetland causes an electrochemical corrosion. Then, if the contamination level decreases, the corrosion rate in treated brass parts by steel shots decreases also.

Search in the case of blast cleaning for the brass parts by steel shots has not been done previously. Using the spherical shape of the abrasive projected with a moderate impact velocity will be a solution in this case.

A sign of Aylesbury Automation's new policy of moving into multi‐part assembly work is the company's recent completion of three important electrical assembly contracts, one of them using a 12‐station machine and another employing a computer‐controlled X‐Y table.

IN presenting the 1975 Viscount Nuffield Memorial Paper entitled “The attempt to reform British Leyland's Industrial Relations” its author, Mr. Pat Lowry (Director of Personnel, British Leyland Ltd.), asserts that British Leyland did not invent strikes — it inherited them. It is to be wondered whether Mr. Lowry was not too close to events to understand fully the nature of the illness which, in recent times, has gripped British Leyland and, indeed, other car manufacturers. British Leyland were not short of specialists and consultants during recent years, neither was there any lack of diagnoses or of treatments.

The fundamental purpose of any automatic machine is to reduce or even eliminate completely the need for manual labour and, most important, to give the highest possible output. Achievement of the latter requirement generally means that the machine is designed to handle one type of component only, and any variation in component design necessitates either another machine or modification of the original machine. In other words, automatic machines are, in general, not flexible or adaptable. The plating industry provides an exception to this generalisation because the use of automatic machines capable of a variety of operations is now established practice. In this article is described an automatic programme plating machine designed specially to give maximum flexibility. It is new to this country, and the first machine has now been built under licence.

The purpose of presented study is to investigate the development of the barreling obtaining the variation of the surface area during upsetting of cylindrical specimens for various metals and alloys.

Variations of the surface areas were first obtained analytically using mathematical equations for uniform and non‐uniform upsetting. Barreling contours were accepted as circular segments in the development of the equations. In the experimental part of the study, barreling radii and other related dimensions of upset specimens were measured and inserted into the developed equations in order to obtain the variations of total specimen surface areas.

As it is expected, barreling effects the variation of total surface areas of the specimen. It can be concluded that the total surface area first decreases at low upset ratios for all the test materials and then begins to increase as the upset ratios increases. Consequently, total surface areas for non‐uniform upsetting are always smaller that those of uniform upsetting.

Five kinds of materials were used in the experimental part of the study. Specimens were also upset without lubrication. A relatively slow hydraulic press was used during the experiments with 5 mm/s ram speed.

Although the study has not direct implications for the practical purposes in forging area, results can be used as a very useful source of information for researchers in this field to plan their studies. Variation character of total surface area obtained in the study may give useful data in analyzing the deformation patterns in upsetting.

The effects of barreling on the material behavior in upsetting for non‐uniform conditions were analyzed with respect to variation of total specimen surface area. This point of view may be extended for different materials and friction conditions.

IT has long been the aim of aero‐engine designers to reduce the number of external pipes and this has been accomplished to some degree by the introduction of internal oil and coolant passages. But for all that, there are still a considerable number of pipes attached to the outside of most aero‐engines and it will be obvious that the correct maintenance of these is of paramount importance.

The paper describes two well‐known and occasionally confused mechanisms for degradation of electronic circuitry. Intended as a tutorial for individuals working in electronic packaging who have limited background in materials and little experience with these mechanisms, the paper defines and describes the two latent shorting phenomena. Major papers and conferences dealing with the phenomena are cited. Electrolytic or electrochemical shorting is an electrical field‐induced mechanism that can destroy the integrity of modern, densely packed circuits operated in the presence of moisture and ionic contaminants. Examples of copper migration to form electroplated shorts in both thick film hybrid multilayer and printed circuit multilayer boards are discussed, and common features to both systems are outlined. Related mechanisms that may occur with the simple electrochemical (metal plating) mechanisms to produce a broad array of electrical isolation breakdowns are also described. The closing of this part of the paper is a brief review of the Sarnoff‐developed RCA/GE multilayer copper materials system. By design this system solves the problems raised regarding thick film copper multilayer latent failure mechanisms. The discussion of whisker growth is limited to proper whiskers, including those that grow without the application of external stress, squeeze whiskers, and whiskers that result from classic electromigration. All of these grow from solid sources in contact with the whisker. The whisker growth direction is not electrical field related. Identification is made of Sn, Cd, Sb and Zn as the materials classically found to grow whiskers at room temperature. Avoiding the use of electroplated films of Cd, Sb and Zn in close proximity to electronic circuitry is encouraged, and the modern requirements that Sn films be used only after melting, or be alloyed with lead, and not on brass substrates are discussed. In more recent literature indium alloys have been identified as room temperature whisker growth systems. Finally, mechanical design to eliminate squeeze whisker shorting that can result from fasteners in contact with the above and other metals is briefly treated.

The paper's aim is to analyze and assess the importance of a recent US Court of Appeals for the First Circuit decision in the case of Sun Capital Partners III LP v. New England Teamsters and Trucking Industry Pension Fund with respect to the court's conclusion that a private equity fund constitutes a “trade or business” for purposes of the ERISA multiemployer pension withdrawal liability and that, therefore, the fund could, under a “piercing the veil” type of approach, be held liable for the ERISA withdrawal liability of a bankrupt portfolio company.

The paper provides historical background on termination and withdrawal liability under ERISA; explains the facts of the Sun Capital case; and offers preliminary reflections on the “investment plus” approach in ERISA context, the significance of the offset mechanism, why the Sun Capital decision is a significant victory for the Pension Benefit Guaranty Corporation, the liability of one portfolio company for the pension obligations of other portfolio companies owned by the same private equity fund, potential unintended consequences for tax-advantaged benefit plans of portfolio companies; the possibility that different pension plans at different portfolio companies may violate non-discrimination rules, the application of Sun Capital beyond ERISA, and the potential effect of this ruling on taxation of carried interest.

The employer and all “trades or businesses” in its “controlled group, including, under certain circumstances, a private equity fund, are liable for the employer's share of unfunded pension liabilities if the employer withdraws from a multi-employer defined-benefit pension plan.

Practical guidance from experienced financial services lawyers is given in the paper.

THE elastic members used in flexible engine mountings are nearly always made of rubber, cither natural or synthetic, bonded or unbonded. The reason for this is that although metallic springs could be designed to have the required stiffness properties they have very little natural damping and would allow very large amplitudes to build up at resonant conditions unless some external damping device such as friction disks or oil dashpots were employed. Also it is a difficult matter to anchor a metallic spring in such a way that fretting will not occur at the fixing point. Rubber on the other hand has considerable damping properties and it is this (plus its high specific resilience) which has largely determined its pre‐eminence in this field.