The investigation of the physical properties of an electrical porcelain insulator manufactured from locally sourced materials

Abstract The work aims to evaluate the effect of temperature and composition on the physical properties of ceramic electrical porcelain insulators, produced from locally sourced materials in Nigeria. The basic raw materials of triaxial porcelain (Kaolin, feldspar, and quartz) were pulverized, milled for 22 h, and sieved using a 200   μm mesh size. The chemical composition and characterization of the raw materials were obtained using X-ray diffraction (XRD) and X-ray fluorescence (XRF) analysis. The mixtures were formulated using sodium silicate as a deflocculant to help produce the ceramic porcelain samples. The green samples were weighed and fired at temperatures of 1200 °C and 1250 °C. The samples were subjected to 1 h of boiling plus 2 h of soaking. The slip casting technique was used in the production of porcelain insulators. The linear shrinkage, water absorbance, apparent porosity, and bulk density were measured and studied as a function of firing temperature. The apparent porosity and water absorption decreased as the firing temperature increased. The bulk density increased gradually from 1200 °C to 1250 °C and the percentage of moisture remained fairly unaffected by the temperature increase. The linear shrinkage was also found to increase as the firing temperature increased. Despite having the same composition, the average physical properties of the locally manufactured insulators revealed that those manufactured at higher temperatures provided a better insulating effect than those manufactured at lower temperatures. In other words, it shows that excellent ceramic porcelain insulators can be manufactured from locally sourced materials using the appropriate composition and firing temperature.