Summary
Power transformer plays a vital role in power system network, and it mainly consists of liquid and solid insulations. In this mineral oil plays a major insulation role and cooling purpose. Moisture and prolonged electric stress leads the way for ageing in transformer insulation. It results in degradation of insulation properties and hindrance in uninterrupted operation. Due to thermal degradation, insulation loosens its dielectric withstand properties. To avoid this, periodic condition monitoring is required to protect the transformer insulation. In this work, an effort has been taken to investigate the aged mineral oil using semiconductive nanocomposites by retreatment technique. The nanocomposites are added with the aged oil in different volume fractions to evaluate the enhancement level of aged oil for reutilization purpose. The critical properties like breakdown voltage, dielectric loss, resistivity, dielectric permittivity, viscosity, flash point, and acidity of the samples before and after treatment are measured according to American Society for Testing and Materials (ASTM) and International Electro‐technical Commission (IEC) standards. It is found that semiconductive nanocomposites improve the critical properties of aged oil and suitable proportion of volume fractions shows impressively enhanced results than base fluid samples. The result paves a new way in economic retreatment of aged oil under environmental friendly nature for reutilization purpose.
Super plastic forming is a manufacturing process utilized in the automotive industry like vehicle structures to produce complex geometries of aluminium or magnesium alloy components which cannot be fabricated at room temperature. The technique has proven to be an efficient cost-worthy process in forming various lightweight components for aerospace and medical applications During the process, parameters such as die entry radius, pressure, temperature and material thickness at the sheet die interface greatly influence the metal flow and also depends on product quality. The aim of prsent work is to optimise the conventional super plastic forming process parameters for getting the better quality with proper dimensions of hemispherical cup out of AA2024 sheet. The sheet is placed in a die, which can have a simple to complex geometry depends on the final part to be produced. It is shaped into the hemispherical cup using compressed air. These input process parameters were varied and output parameters such as thickness, maximum height, diameter and minimum forming time of cup were studied and L9 Orthogonal array with a specific end goal to acquire the yield parameters influencing item quality, both VIKOR and ANOVA were assessed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.