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Whether in the wet or dry process fields of cast iron enamelling there would seem to be need for improvement in the smoothness and soundness of castings. Efforts to this end could well make the use of recent enamel developments more profitable for the enameller, for what is the use of greater covering power, for example, in an enamel, if it is still necessary to apply a thick coating to obtain a smooth finish?

An extensive investigation simulating the behaviour of coal tar protective systems on steel pipelines under concrete weight coatings has been carried out. In particular the study has been made of the behaviour of synthetic primer/high temperature coal tar enamel with glass reinforcement under the stresses caused by expansion of the steel pipe within its concrete weight coating. The possibility of shearing of the sacrificial anodes has been given special consideration. At high oil temperatures there tends to be an initial creep of the pipe which gradually ceases within 1/2 weeks, but the total movement amounts merely to a few millimeters. This has been found to apply up to temperatures in excess of 100°C. In order to establish this conclusion, laboratory studies were carried out by three different techniques and the effects evaluated. At elevated temperatures some coal tar oils pass from the enamel to the concrete, resulting in an increase in softening point of the coal tar enamel of up to 20°C. The resistance to creep of the enamel is thus greatly increased while the integrity of the corrosion protective coating is maintained. The conclusion that the coal tar enamel system provides a fully reliable protection at the highest submarine oil temperatures is borne out in experience. A North Sea line has been operating satisfactorily at 113°C, for the last four years.

In terms of protection and enhancement of metals, vitreous enamel remains unequalled. Far‐reaching technical improvements have broadened its adaptability and simpler, cost‐saving application and processing techniques have been developed.

The purpose of this study is to find the best geometries among the cylindrical, enamel and honeycomb geometries based upon the mechanical properties (tensile test, compression test and shear test). Further this obtained geometry could be used to fabricate products like exoskeleton and its supporting members.

The present research focuses on the mechanical testing of cylindrical, enamel and honeycomb-shaped parts fabricated through multi-jet printing (MJP) process with a wall thickness of 0.26, 0.33, 0.4 and 0.66 mm. The polymer specimens (for tensile, compression and shear tests) were fabricated using a multi-jet fusion process. The experimental results were compared with the numerical modelling. Finally, the optimal geometry was obtained, and the influence of wall thicknesses on various mechanical properties (tensile, compression and shear) was studied.

In comparison to cylindrical, enamel structures the honeycomb structures required less time to fabricate and had lower tensile, compressive and shear strengths. The most efficient geometry for fully functional parts where tensile, compressive and shear forces are present during application – cylindrical geometry is preferred followed by enamel, and then honeycomb. It was found that as the wall thickness of various geometries was increased, their ability to withstand tensile, compressive and shear loads also enhanced. The enamel shape structure exhibits greater strain energy storage capacity than other shape structures for compressive loads, and the strength to resist the compressive load will be lower. In the case of cylindrical geometries for tensile loading, the resisting area toward the loading will be higher in comparison to honeycomb- and enamel-based structures. At the same time, the ability to store the stain energy is less. The results of the tensile, compression and shear load finite element analysis using ANSYS are in agreement with those of the experiments.

From the insight of literature review, it is found that a wide range of work is done on fused deposition modeling (FDM) process. But in comparison to FDM, the MJP provide the better dimensional accuracy and surface properties (Lee et al., 2020). Therefore, it is observed that past research works not incorporated the effect of wall thickness of the embedded geometries on mechanical properties of the part fabricated on MJP (Gibson, n.d.). Hence, in this work, effect of wall thickness on tensile, compression and shear strength is considered as the main factor for the honeycomb, enamel and cylindrical geometries.

The results of a recent study conducted at the US National Bureau of Standards, indicate that spalling in vitreous‐enamelled aluminium is caused by the corrosive attack of moisture and moisture‐salt mixtures at the enamel‐metal interface.

Summary The properties of coal tar systems and the mechanical requirements of pipeline protections before and after installation of the pipelines are defined. Correct specification related to the particular service conditions and adequate inspection are of paramount importance. With correct selection of primer, grade of coal tar enamel and glass reinforcements coal tar based systems are providing the most reliable protection under almost all service conditions.

With the increasing severity of the ever‐expanding range of synthetic detergents being made available, the question of the resistance of enamels to attack by them becomes more important. Testing apparatus and methods used for the evaluation of the resistance of these finishes are covered in this article as well as the factors affecting their resistance.

Cannon Industries Ltd., have opened a £3/4m. completely automated, electrophoretic enamelling plant for their gas cookers and fires at their Bilston, West Midlands works.

Reports the effects of composition and curing temperature on the film properties of three water reducible enamels prepared from palm stearin alkyds. The properties studied were hardness, flexibility, and adhesion. While all the formulations exhibit excellent adhesion, generally increasing the melamine content and curing temperature can increase the hardness but reduce the resistance to cracking and deformation of the coating. Applies Fourier transform infra‐red spectroscopy (FTIR) to the study of the curing reactions. Finds that FTIR is able to identify the predominant cross‐linking reactions.

The purpose of this study is to analyze door-panel alignment defects seen in built-in ovens manufactured in one household appliances company's plant. Alignment defects in oven door panel substantially affect aesthetics of the product which is an important aspect in driving customer preference and satisfaction. Therefore, this study aimed to increase the initial 3.1 sigma level of oven-manufacturing process to at least 4 sigma level by decreasing a particular door-panel alignment defect, which constituted 67.7 percent of the overall alignment defects.

The goals were achieved through a structured Six Sigma implementation with lean element by utilizing various Six Sigma tools such as workflow, Pareto-analysis, measurement system analyses, control-charts, process capability analysis, cause-and effect-diagram and hypotheses tests. A non–value-added step was also eliminated through the lean approach.

Through Six Sigma implementation, the initial 3.1 sigma process performance level has been increased to 4.4 sigma level leading to substantial decrease in alignment defects.

In the quality management literature, not many papers directly deal with aesthetics and appearance problems of the products especially in the household appliances industry. Moreover, hypothesis testing is not frequently used in Six Sigma implementations in the literature. In addition to limited usage of hypothesis testing, very few studies conducted a thorough measurement system analysis. Considering these gaps in the Six Sigma literature, this study fills an important gap in research by implementing a detailed Six Sigma study, enhanced with hypothesis testing and a thorough measurement system analysis, on the aesthetics and appearance of the product.