Department of Industrial and Manufacturing Engineering

Permanent URI for this collectionhttps://cris.hit.ac.zw/handle/123456789/9

Browse

Now showing 1 - 15 of 15

IMPACT OF A PREVENTIVE MAINTENANCE PROGRAM FOR HVAC SYSTEMS IN HOSPITALS: A CASE STUDY OF KITWE CENTRAL HOSPITAL
(International Journal of Scientific & Engineering Research,, 2013-09-01) Mutenhabundo, Winnie; Bupe, Mwanza
he purpose of the research was to assess the benefits that come with implementing a preventive maintenance system in the hospital heating, ventilation and air-conditioning (HVAC) systems. The run-to-failure maintenance strategy of the HVAC system practiced at Kitwe central hospital affected the quality of health operations considering the increase in demand due to population growth. The researchers set objectives focusing on minimizing downtime to sustain the reliability of the equipment, lowering utility costs and greatening comfort for the building’s occupants. Initially, the types of HVAC equipment at the hospital were identified and an inventory list was developed. The Mean Time Between Failures (MTBF) of the equipment was then established together with the lead times of the inventory items. Finally, the design of a replacement program based on the gathered data was developed. With the implementation of the preventive maintenance program, the benefits of the research came doubled folded; the reliability of the HVAC equipment increased and high utility costs which were incurred due to the frequent breakdowns and poor utilization of machines and employees reduced significantly. The researchers recommend the preventive maintenance for the HVAC system not only to Kitwe hospital but to other hospital for operations enhancement in promotion of good health
Conceptual Design Framework for Developing a Cylindrical Robot Manipulator for Material Handling in Zimbabwean Small to Medium Enterprises: A Finite Element Approach
(Int'l Journal of Advances in Mechanical & Automobile Engg. (IJAMAE);, 2014) Masike, Rujeko; Garikayi, Talon; Tigere, Godfrey
In many small to medium engineering companies in Zimbabwe the need for material handling devices has become a necessity. There is lack of machinery that could increase production rate, improve product quality and reduce manufacturing costs while maintaining safe working environments. Material handling is a bottle neck during production due to lack of proper equipment and plant layout thus this research seeks to improve the material handling system through the conceptual design of a framework for the application of a cylindrical robot. There are many robots in the market that will improve material handling effectively. The purpose of this paper is to present a framework that has a structured approach for developing cylindrical robots based on finite element analysis methods that will be used by small and medium engineering enterprises (SMEs).This will enable the SMEs in developing nations to maintain competitive prices on products with minimal work accidents. The research explores the current literature and design approaches used to develop cylindrical robots. The paper also provides detailed methodologies to be used for structural analysis, component simulation and performance evaluation of the machine through finite element analysis (FEA). The framework provides suitable guidelines for designers to make appropriate decisions from the initial design stage to the commercialization of the design. The authors conclude that the preliminary framework be applied to formalize design steps for sim ilar material handling machinery implementation in the SME sector.
Production of Bio Fuels from Eichhornia Crassipes Algae
(International Journal of Research Studies in Biosciences (IJRSB), 2014-02-01) Sengudzwa, Thamari; Chirinda, Ngoni; Manyuchi, mercy; Mawere, Cephas
In a bid to promote renewable energy and control of dam pollution, algae, a plant notorious for growing in waste water dams was used to produce algae oil. Algae plantswere collected from the dam and algae oil was extracted using the Soxhlet procedure. Hexane was used as the solvent. A conversion rate of 14% was obtained for an extraction time of 6 hrs. This algae oil will then be trans-esterified to produce a bio fuel. The bio fuel can be used as an alternative to petrochemical fuel and is sulfur free. Moreover, it is proven to be the cleanest fuel for combustion systems.
Process Optimization Using Design for Environment Concept in the Input System of a Paint Disperser
(International Conference on Advances in Marine, Industrial and Mechanical Engineering (ICAMIME'2014), 2014-08-15) Mutenhabundo, Winnie; Chirinda, Ngoni.; . Mugwindiri, Kumbi
These Design for Environment has gained millennium goal commendation on Sustainable Development in order to promote green technologies. In this research, the Design for Environment concept was employed for the optimization of an input system of a water-based paint disperser in which the respirable pigment dust exceeded the threshold limit. An audit revealed waste streams and the levels of emissions and their impacts were assessed. The researchers set their objectives seeking to reduce the negative effects. A Cleaner Production Assessment was done to identify, quantify and find options to minimize wastes. ISO 14 001 was identified as a tool toimprove environmental performance. Life Cycle Assessment was done to assess the environmental aspects and the potential environmental burdens. A Design for Environment product that reduces dust emissions was identified. The synthesized product was recommended for fine tuning and prototype development. The researchers recommend Design for Environment technology for process optimization
DESIGN OF A MICROCONTROLLER BASED TEMPERATURE-HUMIDITY CONTROL SYSTEM OF BIO-MASS FIRED TOBBACCO CURING BARNS FOR SMALL TO MEDIUM SCALE FARMERS IN ZIMBABWE
(Harare Institute of Technology, 2015-01-03)
High quality cured tobacco is one of the most foreign currency generators in Zimbabwe. Currently curing process within the small to medium scale farmers is through curer’s experience. In order to reduce this dependency and achieve high quality the curing process requires a well-designed temperature control system. A biomass fired flue curing tobacco barn design for small-medium scale farmers in Zimbabwe with a clear objective to control temperature and humidity is the focal point of this paper. The designed barn accommodates capacity of small-medium tobacco farmers with a provision to use firewood, coal or dung in as source of energy. To reduce curer experience dependency a furnace with seized fuel trays, which are charged into the furnace as per calculated frequency for every curing stage basing on heat content and type of fuel was incorporated. The designed barn system that, have an outside control box contains a combination of heat extraction fans, cold air blowers and humidifiers that regulate temperatures and humidity levels to required levels for every curing stage under the instruction from 16F887 microcontroller. This has replaced the primitive way to check thermometers inside the barn even at high temperatures of about 80°C. Commendable energy efficiency was realized in various system performance simulations through different techniques
Reliability Engineering: A Demonstration of How Reliability Engineering Techniques and Methods Improve Processes, Products and Services
(International Conference on Mechanical and Industrial Engineering (ICMIE'15), 2015-07-14) Chikuruwo, Mary N.H; Chikowore, Takawira R
Understanding what, when and where to use the wide variety of reliability engineering tools available helps in achieving the highest reliability in products, processes and services. This paper outlines the value of using Weibull Analysis, Reliability Block Diagrams Reliability Centered Maintenance and Root Cause Analysis and as techniques for processes, products, equipment and services improvement. Reliability Engineering tools help to determine the relationship between the process and the equipment. A demonstration of where and how the reliability engineering techniques can be applied is shown in the research. Every product and process design and their development are unique such that meticulous planning is required to map the reliability tasks to the identified constraints. A product with complex multidisciplinary integrated functions requires efficient reliability tools. These tools are required to be used to assess built-in safety and reliability features of the product under an applicable environment. The techniques discussed in this research will help in determining the present and future reliability of the products or processes.
An Economically Sustainable Urban Public Transport Framework: System Dynamics Modelling Approach to Reduce Public Transport Liberalisation Impact in Harare City
(International Journal of Science, Technology and Society, 2015-07-25) Mupfumira, Portia; Wirjodirdjo, Budisantoso
Public transportation plays a key role to socio-economic development of any nation. This service enhances people’s livelihood framework by facilitating mobility and accessibility to services. Moreover, there is clear global evidence that a well performing public transport is an important enabler of sustained economic prosperity. Rapid urbanization in developing countries has resulted in transport facilities and infrastructure failing to cope with demand resulting in congestion, movement delays, high travel costs, and construction of holding bays in order to decongest the city, which will contribute to an increased usage of nonrenewable energy. This prompts implementation of non-comprehensive strategies such as partial deregulation of transportation systems that caused further deterioration in economic sustainability. An economically sustainable transport system advocates for mobility, resource, and operational efficiency. This research focuses on developing a bus investment conceptual framework of a public transport system that improves mobility, resource, and operational efficiency to aid in sustaining of public transportation system for an unforeseeable future. With this in mind, a Harare bus investment system has been modelled as a policy framework model to evaluate its economic sustainability. This will help develop a long-term economically sustainable public transportation and reduce the overall impact of the earlier liberalisation of the transportation sector.
Design of an Automated Vibration Monitoring System for Condition Based Maintenance of a Lathe Machine (Case Study)
(Conference: 2016 International Conference on System Reliability and Science (ICSRS, 2016-11-21) Chikuruwo, Mary Nyaradzayi Hughslar; Maregedze, Laurence; Garikayi, Talon
This article presents an automated vibration monitoring system for a lathe machine. This study was motivated by the fact that machine production time was wasted during planned maintenance when, most times, the machines did not require any maintenance at all. Also, the periodic intervals used did not depict the correct ageing of the machine components which resulted in unexpected failure of the machine. Planned maintenance schedules are done with the assumption that the machine is going to breakdown after a certain period of time. The aim of this research was to come up with a vibration monitoring system for a lathe machine, which included incorporating an electronic circuit in the system, use of liquid crystal display for improved user interface and use of vibration sensors to determine the vibration level of the machine. Experimental research design was used to determine the acceptable ranges of vibration amplitudes in order to classify the amplitude into 4 groups namely: extremely rough, rough, acceptable and smooth. The designed system produced consistent vibration amplitudes for both machining and nonmachining operation. The system used different indicators linked to the main processor of the circuit which monitors the machine real-time performance. It was capable of alerting the user when the vibration amplitude was out of range and also to switch off the machine when the vibration threshold was exceeded. The vibration monitoring system helps in damage control and enables preventive measures to be taken before damage occurs.
PROGRESS IN INFRASTRUCTURE AND PROPERTY DEVELOPMENT IN AFRICA
(Proceedings of the 9th Zimbabwe Institute of Engineers Congress,, 2017-09-05) Mhonde, Godknows; Manyuchi, Mercy
A Review of the Existing Solar Irradiation Databases
(International Journal of Engineering Science and Computing, 2017-10-21) Kwinjo, Gerald; Munetsiwa, Tendaishe; Arora, R
Huge gains in the form of time and cost savings, increased productivity and efficiency will be obtained by designers and researchers of solar technology systems if relevant information is available and easily accessible for every site in the world. The Internet has played a major role in making this information available to users through various online databases for solar radiation. However, often times many of the available databases do not meet actual users ‘needs. In general most users prefer hourly or daily irradiation data with a spatial resolution of a maximum of 20km, but unfortunately the number of ground measuring station around the globe are too small to attain such accuracy. The accessibility is also made poor by the complexity of the data which comes from various storage standards, units, ways of expressing time etc. in the databases. Moreover, users often face difficulties in selecting the database that meet their needs for a particular time and location. This paper provides a comprehensive review of the available online databases with the information that they provide and their advantages and disadvantages. Demonstrations are also shown for the applicability of one online design software called HELIOSCOPE. Recommendations and proposals for future work were given to address the discrepancies between users’ needs and the available databases
,A Paper on the Testing Procedures and Protocols for Concentrated Solar Thermal Technologies
(International Journal of Engineering Science and Computing,, 2017-11-01) Kanyowa, Tatenda; Ndala, Emmanuel; Nyakujara, Garikayi Victor; Sahoo, U; Das, Subhra
Interest in solar thermal technologies have grown over the past two decades due to the increasing energy deficit around the globe as well as increasing carbon levels in the atmosphere. Unlike solar photovoltaics, solar thermal technology has the potential to provide both high and low-grade energy which can be used for several applications from household, industrial to electricity generation. This document will focus more on concentrated solar technology (CST) which are essential for the future because they can offer flexibility and potential high dispatch ability in power plant applications. In order to fully utilize CSTs, performance standards of these systems are being setup. These can help to ensure that for a certain CST device, it must meet certain performance criteria in order for it to produce favourable results. Performance standards for these systems also help in allowing interchangeability of certain components. Testing of a CST system is done in several steps depending on the type of system. Usually the most ideal conditions are required to test the performance of a CST system. Clear skies with radiation of 450W/m or above are usually ideal to execute this process. The testing equipment is adjusted so that near steady state conditions are established. CST systems must have high optical efficiency for good performance since they rely on reflection of the direct radiation onto a receiver. Good reflecting materials must be used to guarantee better performance of the system since the system will always have losses which will reduce the expected thermal efficiency of the system. These are some of the parameters and conditions which will be discussed in this paper
CAD/CAM 1
(HIT, 2023-11-13) HIT
Engineering Drawing and Graphics 1
(HIT, 2023-11-14) HIT
Computer Engineering
(HIT, 2024-12-13) HIT
Finite Element and Boundary Element Methods
(HIT, 2025-07-13) HIT