Natural Honey and Nigerian Gum Arabic as Composite Binder for Expendable Foundry Cores

Potentials of foundry sand core binders made with composites of Nigerian gum Arabic and natural honey were investigated. Core specimens made with silica base sand bonded with composites of each of four grades of Nigerian gum Arabic and honey were classified and tested for tensile and compressive strength; permeability and shatter index to ascertain binder efficacy. Tensile strength specimens shaped like figure number eight were oven baked at 180°C and 200°C; cooled to room temperature and tested with universal strength machine. Cylindrically shaped permeability and shatter index specimens were tested with permeability meter and shatter machine. Results showed that cores baked at 200°C attained higher strength at shorter baking periods than those baked at 180°C. Honey improved tensile strength by 15%, 17%, 16% and 17% over the plain gum Arabic grades 1, 2, 3, 4 bonded cores, respectively. It improved compressive strength by 7%; permeability and shatter index by 2%. Composites cores of 3% gum Arabic grade 2 - 4 with 0.5% honey baked at 200°C were suitable for magnesium, copper bronze, non-intricate aluminium, classes III, IV, V iron and steel castings. Cores made with composites of 1.5 - 3% honey and 3% gum Arabic grade 1 - 4 were suitable for intricate aluminium, copper brass, class II - V iron and steel castings

Inhibition Characteristics of Watermelon Oil on Aluminium in Acids and Saline Water

The response of aluminium specimens immersed in saline water and 1 molar aqueous solution of acetic and sulphuric acids towards corrosion inhibitive actions of oil locally extracted from seeds of watermelon was investigated. Mirror polished aluminium specimens measuring 10-mm diameter by 20-mm length were immersed in batches of plastic beakers containing 50 ml of saline water and acid solutions with watermelon seed oil concentrations by weight of 0.0, 0.5, 1.0, 1.5 and 2.0% as inhibitors. Weight loss method was used to monitor corrosion rate of the specimens over a period of 240 hours. Results showed that reasonable corrosion and inhibition occurred in specimens immersed in solutions of sulphuric and acetic acids while weight losses in specimens immersed in saline water were very minimal and beyond detectable limits of weighing apparatus used. Statistical average reductions of 26, 1.5, 2 and 16% in corrosion rates were achieved, respectively, with the addition of 0.5, 1.0, 1.5 and 2.0% watermelon seed oil for specimens immersed in sulphuric acid, while 49, 6, 28 and 20% reductions were achieved for aluminium in acetic acid solutions. The oil was therefore more inhibitive in acetic than sulphuric acids

Characterization of Foundry Sand Cores Bonded with Raw Nigerian Water Melon Seed Oil

Raw oil extracted from Nigerian variety of water melon seed was used as sole binder for foundry sand cores. Specimens were characterized for foundry properties that included baked tensile, green and baked compressive strengths; baked collapsibility, green permeability, bulk density and shatter index to determine the efficacy of the oil in the absence of additives for core application. Except the baked collapsibility test that was carried out at a temperature of 6000C, other specimens were oven baked at 2000C and oven cooled before the tests. Green permeability and compressive strength tests were carried out on freshly moulded specimens. Standard foundry laboratory/workshop equipment available at Nigerian Machine Tools Company Limited, Oshogbo was used to conduct tests under standard conditions. Results showed that cores with compositional mix of 1-3% water melon seed oil had adequate foundry characteristics for production of classes II-V iron and steel castings. Cores bonded with the oil were unsuitable for classes I and II iron/steel and non ferrous castings including copper, aluminium and magnesium alloy due to the poor baked tensile strength and collapsibility values. Results of green permeability, shatter index and compressive strength of tested cores were very sufficient for casting both ferrous and non-ferrous alloys. Keywords: Melon seed, oil, cores, baked, foundry, characteristics.

THE ROLE OF AGRICULTURE IN THE ECONOMIC DEVELOPMENT OF NIGERIA

Nigeria is on its way to modern development. Branding itself as the “giant of Africa”, the country now needs to prove its potential by raising its standards to a level with other fast developing economies of the world. The vision 20-20-20 program this country is currently pursuing is a major step to achieve this goal. Nigeria, according to its seven point agenda, is focussing on developing agricultural as an important strategic move. This paper uses trend analysis in terms of a historical and current perspective and various descriptive methods to analyse the development of Nigeria through each decade since its independence in 1960 and examines the factors that have had an impact on its agricultural productivity. This will aid in describing and predicting the performance of the agricultural sector in Nigeria and as a result, the overall economic development of the country in the coming decade. This paper proves that an in-depth research on the development of the agricultural sector is essential to the progress of the country. Also, it is important to find out what has not worked previously and why, before taking any steps to develop the agriculture or the economy. The basis of this development should start with the empowerment of the poor

Determination of the Suitability of River Gurara Bed Sand Bonded with Clay for Foundry Casting Moulds

The study investigated foundry properties of bed sand from river Gurara located in Niger State, Nigeria for use in production of foundry casting moulds using bentonite or kaolin clay as binders. A quantity of representative sand sample collected according to AFS procedure was washed, sun dried, classified on vibrated sieves and used for the experiment works. Specimens bonded with 0.5-3% of either bentonite or kaolin clay were prepared in accordance with AFS standard and tested for refractoriness; permeability; green/dry compressive strengths; moisture content; green hardness and shatter index using equipment including moisture teller, universal strength machine, shatter index and Rockwell hardness testers. The BS classification sieve result showed it consisted of 42% medium and 27% fine sand that will produce castings with fine surface finish. The physiochemical analyses done with XRF machine showed the sand was made up of 88% silica with metal/alkali oxides including Fe2O3 (3.02%), K2O (3.02%), Al2O3 TiO2 (2.12%). It had refractoriness of 1,500oC making it suitable for casting moulds for non-ferrous metals, light/heavy grey iron and some grades of steel. Tested foundry properties including permeability (167-136No); green compressive (26-38KN/m2), dry compressive strength (200-360KN/m2); hardness (65-80); shatter index (88-70) for kaolin bonded specimen and  (130-116); (18-34KN/m2); (182-238KN/m2); (48-54No); (110-76N0) for bentonite bonded specimen when compared with existing foundry standards also confirmed suitability of sand bonded with these clay for the applications mentioned. Keywords: Gurara river, bed sand, Kaolin, Bentonite, Foundry Keywords: Claims, Delivery, Administration DOI: 10.7176/IEL/9-2-05 Publication date:March 31st 201

Hybridizing Effect of Palm Frond Fibre on Helmet Shell Cast from Elaeis Guineensis Male Flower Bunch Fibre Reinforced Biocomposite

Biomass fibres obtained from agricultural wastes have found application in the production of structural reinforcement for bio-composites used for manufacturing of engineering components because of their low cost, biodegradable and eco-friendly advantages. Ademoh and Olanipekun (2014) had produced motorcycle safety helmet using a bio-composite reinforced with 20% male flower bunch stalk fibre. In this research, 20% weight of treated hybrid composite from treated oil palm male flower bunch stalk fibre and oil palm frond fibre in the ratio of 3 to 1 respectively were used in reinforcing unsaturated polyester resin to fabricate anti-crash helmet shell using hand lay-up method. The mechanical performance of the helmet shell was determined and the results obtained were compared with past literatures. From the result, hybrid composite of oil palm male flower bunch stalk fibre hybrid and oil palm frond fibre with unsaturated polyester has good mechanical attributes and can replace ABS plastic commonly used in conventional helmet productions. On comparison with immediate preceding work of Ademoh and Olanipekun (2014) the 15% male flower bunch/5% palm frond reinforced bio-composite of this study showed improvement 77.06% on modulus; 68.20% on impact strength and 13.61% on harness and reduction of 21.04% on toughness. Keywords:  palm frond fibre, male flower bunch stalk,  fibre, polyester, helmet shell

Assessment on Radiation Hazard Indices from Selected Dumpsites in Lafia Metropolis, Nasarawa State, Nigeria

This research reports an assessment of ionizing radiation in some chosen Dumpsites in Lafia Local government area of Nasarawa State. Ionizing radiation measurement was conducted at four Dump sites. The survey was done using a radiation survey meter (Radex one Outdoor 55130719 NA). Radiation exposure rate in micro sievert per hour (μSvhr-1) was measured. Readings were taken by placing the detector at gonad level about 1 meter above the ground. Result showed that the average annual effective dose rate in the selected dumpsites were 0.22 mSv/yr for Lafia modern market, 0.17 mSv/yr for dumpsite opposite governor Isa house, 0.15 mSv/yr for Timber shade Lafia and 0.20 mSv/yrfor Science School Lafia respectively with a mean value of 0.19 mSv/yr for all location, while the mean calculated excess life cancer risk (ELCR) is 0.65 x 10-3.Dumpsites yearly absorbed dose rate and their corresponding ELCR values did not exceed the 1.0 mSv/y Basic Safety Standard set for the masses by International Council on Radiation Protection (ICRP, 1999) and mean world average ECLR value of 1.16 x 10-3. Based on these results there are no radiation consequence to the scavengers, dumpsite workers and residents living around the dumpsites

Development of Manually Operated Orange Peeling Device for Domestic Use

Orange a very rich source of vitamin C is a perishable fruit that can only be stored unpreserved for few days before its biological degeneration. When processed to juice, the chemical preservatives that are usually added coupled with the contaminations by its back skin fluid instantly change its natural flavor. This has made many consumers to still prefer freshly peeled fruit to its processed juice. As a solution to laborious hand peeling process that is highly prone to injury due to the sharp tools used several devices have been developed for its peeling. Each of these has its own technical, economic and other shortcomings. This work designed and fabricated a manual orange peeling device with a capability of processing oranges for a domestic family household. The device incorporated a rotary handle through which power was introduced into the system, power screw, spur gear train mounted on a base and cutting blade that performed the peeling function. The fabricated device was operated and assessed to have a peeling efficiency of 97%, generated 2.6% over peeled and damaged oranges and a capacity to peel about 140 oranges per hour as compared to hand peeling that can produce 32 peeled oranges per hour. It is robust, simple to operate and maintain, had good aesthetics and light weight of 619g due to transparent light but strong plastics used to construct the frame and base. Keywords: Orange, peeling, device, household, juice

Development and Evaluation of Maize Husks (Asbestos-Free) Based Brake Pad

The development and evaluation of maize husks as asbestos-free friction material for the production of automotive brake pad was carried out in this work. Asbestos friction material that has been used for over 80 years was found to be carcinogenic in nature and has prompted several research efforts for its replacement from brake pads. Three sets of composite compositions were made using maize husks as filler material to impart friction properties with varied epoxy resin contents as the matrix that bonded the particles in the mix.  Brake pad specimens were made out of the composites and subjected to mechanical, physical and tribological analyses to ascertain their possible performance in service using standard test procedures, materials and equipment. The particulate size of the MH filler material was 300µm and epoxy resin was in slurry. The result showed that specimen composite 3 with 30% MH filler content having coefficient of friction, abrasion resistance, water absorption, oil absorption, density, hardness, tensile strength, compressive strength, and thermal conductivity of 0.37, 4.470E-6g/m, 0.725%, 0.660%, 0.852g/cm3, 99.34mPa, 14.407mPa, 6.779mPa and 0.330W/mk respectively was optimum in performance. It was observed that reducing the filler content increased hardness, wear rate, tensile strength, compressive strength and thermal conductivity of the composite brake pad, while density, coefficient of friction water and oil absorption got increased with increased MH filler content. The result when compared with those of conventional brake pad made of asbestos and other friction materials of past researches showed that MH particles are an effective replacement for asbestos in automotive brake pad manufacture. Unlike asbestos based brake pad, the composite brake pads are eco-friendly and do not have the health hazards like cancer aggravation, asbestosis, mesothelioma, lung and other ailments associated with use of asbestos bearing components. Keywords: Brake pad; asbestos; maize husks, tribological properties

Design and Fabrication of Shea Nut Steam Roaster

Sheanut (Butyrospernum paradoxum) is an oil rich tropical tree crop, which is indigenous to the West African savannah zone. In Nigeria, most of the shea nut roasters are made of light mild steel materials with openings. The source of heat for the roasting is open fire. This takes time and the mild steel can easily get rusted and contaminate the product. In addition, open fire roasting has the disadvantage of producing burnt crushed kernels which in turn lead to black shea oil formation, loss of vital and essential nutrients.  A shea nut roaster which makes use of steam as source of heat energy was designed and fabricated to be used in roasting shea nut prior to extracting oil from them. It was developed to address the aforementioned problems. The equipment consists of heating unit, roasting unit, power transmission unit and the supporting frame. A gear motor of 0.25kW was selected to supply power to the shaft whose end was welded to the stirrer. The roasting unit consists of three compartments: roasting chamber, steam chamber and insulator chamber. The heating unit has two pipes: water inlet pipe and steam delivery pipe. Also, charcoal burner was attached to the heating unit to help boil the water for steam to form; this steam will then be transported by the steam delivery pipe to the steam chamber which in turn heats up the outer surface of the roasting chamber and thus the crushed nuts inside are roasted through the heat being supplied. The machine was fabricated with about 90% local materials. Test results of the roaster using shea nuts indicate successful heating/roasting, the nuts were not scorched or burnt, rather they were looking dry but fresh, this indicates that the design of the machine suits its purpose for roasting shea nuts prior to oil expelling . Also, roasting capacity of 45kg/hr was achieved. The successful development of this machine will reduce drudgery and time taken associated with the traditional method of roasting shea nuts and therefore will increase productivity and utilization. Keywords: Heating, steam; shea nut; roaster; desig