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.

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

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

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

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

Evaluation of effective baking conditions for grade 3 Nigerian Acacia species bonded foundry sand cores

Abstract: The most effective economical baking conditions were determined for foundry cores bonded with the grade 3 Nigerian acacia species exudates. Silica sand base cores bonded with the material were oven baked at temperatures ranging from 160 to 250ºC for varying periods oven cooled and then subjected to tensile strength tests to ascertain the best baking conditions for different alloy castings. The experimental core specimens were in accordance with foundry test standard, shaped like figure number eight. They were tested with standard universal strength machine equipped with attachment for gripping the cores and an instantaneous meter from which the test values were read. The result were compared with established standard foundry core property table which showed that the class V iron/steel cores are best made with 3% acacia bonded silica sand baked at 160ºC for 1 h. For magnesium cores, sand bonded with 4.5% acacia baked at 160ºC for 1-2 h was optimum. For class IV iron/steel cores 4.5% acacia bonded sand baked at 180ºC for 1 hour was optimal. Sand bonded with 4.5% grade 3 acacia baked at 200ºC for 1.0-2.0 h was optimum for copper, aluminium, classes II and III iron/steel cores. Sand bonded with 8.0-13.0% grade 3 Nigerian acacia species baked at 200ºC for 1.5-2 h was found most effective for class I iron and steel cores

Investigation of the Potentials of Oil Palm Frond Fibre for Thermal Insulation of Food Flasks

Natural fibers obtained from oil palm fronds at Offa, Nigeria were investigated for reinforcement of heat-resistant lining for hot food flasks. Frond fibre was subjected to 5% NaOH chemical treatment to impose better surface property and used to reinforce polypropylene matrix as composites with 10%, 20%, 30% and 40% fibre loading. Treated frond fibre, polypylene matrix and samples of fabricated composites were subjected to standard chemical, mechanical and physical tests including density/hardness, impact/tensile strengths and thermogravimetric/thermal conductivity analyses following standard procedures. The test  equipment included injection molding machine, Instron tensile tester, Tinius impact tester, Rockwell hardness tester, Perkin Elmer instrument and Lees disc apparatus; accessed in workshops/laboratories of Kaduna Polytechnic, Ahmadu Bello University, Zaria, Engineering Materials Development Institute, Akure and Federal University of Technology, Minna. The characterization result showed the composite was nontoxic to humans if it contacted food in the flask. The physical, mechanical and thermal properties showed that only 20%-40% fibre loading was beneficial after which performance declined. Mechanical properties of frond reinforced composites (density, hardness, impact and tensile strength) were adequate for required service condition. The decomposition temperature of the composites was about 4800C which was above 3500C-4350C for most conventional domestic insulators, 2900C for pure treated frond fibre and 4350C for polypropylene matrix. Thermal conductivity reduced from 0.0035Wm-1K-1 to 0.0025Wm-1K-1 for 20%-40% 10mm thick fibre loaded composites. For 50mm thick conventional domestic insulators, it was 0.11- 0.23Wm-1K-1 for polypropylene matrix, 0.066Wm-1K-1 for rock wool, 0.036Wm-1K-1 for glass fibre and 0.03Wm-1K-1 for polystyrene, confirming the superiority of the frond reinforced composites as minimized thermal conductivity is the most critical determinant of material suitable for thermal insulation

Evaluation of the Suitability of Oil Palm Fruit Bunch Stalk Fibre for Lagging of Hot Food Containers

Oil palm fruit bunch stalk fibres obtained after the harvest from a plantation located at Offa, Nigeria. These fibers were treatedwith 5% NaOH aqueous solution, used to reinforce polypropylene polymer and investigated for thermal insulation of hot foodcarrying flasks. Treated fibres were loaded in concentrations by weights of 10%, 20%, 30% and 40% as filler into polypropylenematrix, fabricated into composites with an injection moulding machine with specimen of each formulation analysed for chemical,physical, mechanical and thermal properties including density, hardness, impact/tensile strengths, thermo-gravimetric and thermal conductivity using standard test equipment to ascertain the suitability for heat resisting application. Test equipmentincluded Lee’s disc apparatus, Perkin Elmer instrument, Instron tensile, Tinius impact and Rockwell hardness testers accessed inworkshops and laboratories in Nigeria. The characterization result showed the composite as nontoxic to humans if it contactedfood in the flask. The physical, mechanical and thermal properties showed that only 20%-40% fibre loading was beneficial afterwhich performance declined. Mechanical properties of bunch stalk reinforced composites (density, hardness, impact and tensilestrength) were adequate for the service conditions. The decomposition temperature of composites was about 4800C which wasabove 3500C-4350C for most conventional domestic insulators, 2810C for pure treated bunch stalk fibre and 4350C for polypropylene matrix. Thermal conductivity reduced from 0.11- 0.23Wm-1K-1for polypropylene matrix to 0.0025Wm-1K-1 for40% 10mm thick fibre loaded composite while it was 0.066Wm-1K-1 for 50mm thick rock wool, 0.036Wm-1K-1 for glass fibre and0.03Wm-1K-1 for polystyrene used as conventional domestic insulators. This confirmed superiority of the fruit bunch stalkreinforced composites as for thermal insulation application over common domestic insulator