Design and development of a permanent mould for crucible production

This study aimed at development of a permanent mould for crucible production. Solid-Works was used as the computer aided design (CAD) tool for design and structural analysis of the parts, with necessary design considerations put in place. The fabrication of the mould was carried out at Federal Institute for Industrial Research Oshodi (FIIRO), selecting Mild steel as the parent material. The mould basically consisted of the male and female parts made up of medium carbon steel because of the required strength. It was discovered from the structural analysis that the application of 1.0783 MN/m2 to produce the crucible from the mould is safe because it is not up to the vonmises maximum pressure of similar load of 5.584 MN/m2 , this is lesser than the yield strength of the material which is given to be 2.481 MN/mm2 . This shows that the material and its specification is safe and will not fail for the purpose for which it is designed for. Results showing the displacement and strain analysis revealed that the displacement in the mould is in the rate of 0.001 MN/mm and 0.00173 mm. This displacement is insignificant to cause failure in the part. And the strain is seen to be in the range 2.176 X 10-8 and 2.232 X 10 -5 , the results therefore give confidence in the design to meet requirement. Keywords: Casting, Development, Foundry, Crucible, Mould, SolidWork

Determination of work index of graphite from Samanburkono (Nigeria) using modified bond's method

This report covers the work index determination of Saman-Burkono graphite. The test sample was obtained from Saman-Burkono in Ningi Local Government Area of Bauchi state, while reference material (coal) was sourced from Okaba coal mine, Ankpa Local Government Area of Kogi State. A known weight of graphite sample and coal were crushed, pulverized and ground using the laboratory milling machine. The two samples were grinded with two cells of diameter 3.5cm and 222g weight. The analysis of the feed size fort the two samples was found graphically to be 180μm and 175μm, and ball mill discharge was 130μm and 140μm respectively. The work index of a coal as reference material was 7.65 kWh/ short ton, this was used to calculate the work index of the graphite which was found to be 11.047 kWh/short ton, being the required energy to comminute one ton of graphite.Keywords: Comminution, Graphite, Saman-Burkono, Nigeria, Modified Bonds metho

Comparison of lubricant properties of castor oil and commercial engine oil

The tribological performance of crude Nigeria-based castor oil has been investigated and compared with that of a foreign, 20W-50 high quality crankcase oil, to see its suitability as base oil for lubricating oils in indigenous vehicle and power plants engines. The experiment was conducted using a four ball tester. The results showed that unrefined castor oil has superior friction reduction and load bearing capability in an unformulated form than the commercial oil; can compete favourably with the commercial oil in wear protection when formulated with suitable antiwear agent, hence can be a good alternative base stock for crankcase oils suitable for Nigeria serviced vehicles, and plants engines from tribological, environmental, and non-food competitive points of view