Showing items 1 - 20 of 27

Your selections:

Transformation of a maintenance concept through the use of business engineering techniques.

  • Authors: Theron, Tertius
  • Date: 2012-08-23
  • Subjects: Plant maintenance - Management , Reliability (Engineering)
  • Type: Thesis
  • Identifier: uj:3073 , http://hdl.handle.net/10210/6493
  • Description: M.Ing. , Ever since man had invented the wheel, or for that matter any of his first hand tools, he had a definite need to maintain that object. Man did not have any means to predict failures and he had no idea of how to prevent them. He could not plan for these failures and would not know what material and resources to have on hand. He was obviously restricted to a very primitive and elementary form of breakdown maintenance or a sort of run to break strategy as we would call that in modern maintenance terms. His success could only be measured in terms of the time to the next failure. Due to the nonexistence of engineering standards, the large standard deviation in mean time between maintenance (MTBF) values would render these same values rather useless for predictive purposes. This situation restricted our forefathers to a very reactive approach to maintenance. The astonishing present levels of sophistication in man's skills, engineering design and manufacturing came about through revolution and evolution. This indicates a huge amount of change that has taken place over the years and is still taking place today. As the world is in a constant state of change no business organization can escape the effects of operating m a continually evolving landscape. The very forces of change come about typically through industrial globalization, technological advance, political upheaval, the opening up of new markets and the changing expectations of customers that become more knowledgeable and demanding. For any business to respond to customer needs in a satisfactory manner, that business will have to be highly dependent on logistics. As logistics is a major contributor to life cycle cost (Blanchard, 1992: 70-84) and therefor impacts directly on profit margins, there is a growing need for more effective and efficient management of an organization's resources. Logistic support for any organization or plant is a major consideration in the early design stages of any system or organization or plant. From a logistic support perspective it becomes therefor necessary to assure the effective and economical support of a system, organization or plant throughout its programmed life cycle. One of the most important logistic support elements is maintenance. A lot has been said and written about maintenance. A number of well known philosophies and procedures (Blanchard, 1992: 9-25) such as 'planned preventive maintenance' (PPM), `condition based monitoring' (CBM), 'reliability centered maintenance' (RCM), 'total productive maintenance' (TPM), 'just in time' (JIT), 'life cycle costing' (LCC), etc. have been developed over many years and are applied throughout the world today. Techniques such as 'failure mode effect and criticality analysis' (FMECA), 'fault diagnostics', 'quality circles', and others have also been introduced to the industry. However various studies (Willmott, 1990: 17) have shown that present levels of maintenance management effectiveness are still unsatisfactory. One of the most important reasons for this state of affairs is that maintenance is still viewed by many organizations as a technical activity rather than an integrated management discipline. This misconception is then reinforced by several factors such as that the maintenance department is at its most visible when an emergency malfunction occurs. As soon as the malfunction has been restored, production carries on with its activities and no one asks the question why the breakdown was not anticipated before it occurred and disrupted production. A second reason is that maintenance managers view themselves as fire fighters and not as managers. A third reason is that the maintenance department is viewed as an organizational function with unpredictable response times and erratic priorities. All of these prejudices and misconceptions are costing industry dearly. This study will indicate that much can be done to transform the maintenance function of any organization to such an extent that costs are minimized and plant availability is improved that will ultimately lead to higher profit margins.
  • Full Text:

Reliability engineering management in the petrochemical environment : the air separation unit

  • Authors: Stadler, Richter
  • Date: 2015
  • Subjects: Reliability (Engineering) , Maintainability (Engineering) , Gas separation membranes , Gases - Separation , Sasol (Firm)
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/212776 , uj:21026
  • Description: Abstract: The key processing unit, the “cold box", is fundamentally responsible for air extraction and separation. The cold box is critical in the Sasol Chemical Industries (SCI) environment, due to the importance of oxygen in several processes. Due to the criticality of the equipment, it became necessary to streamline the maintenance process utilized on the cold box. Irregular and unplanned maintenance can lead to unforeseen events and may have safety and environmental implications. The maintenance philosophy that is followed to maintain the equipment is of utmost importance. Sasol conducts maintenance on their cold box with a black box approach, which makes it difficult for the maintenance team to predict failures, resulting in significant losses. The study investigates the potential benefits of an alternative maintenance strategy. The key focus of the research includes an evaluation on the impact of an alternative maintenance approach has on the reliability and stability of the equipment. The research approach includes a global literature study providing potential options for improvements. The viability of these options was tested via a questionnaire conducted with plant personnel with current plant personnel. The questionnaire consists of 28 questions, which are formulated to determine certain data relating to the research question. The questions are divided into six categories, as it is extracted from the relevant sections. See details in Appendix A The categories are: 1. Challenges in the different air separation processes 2. Maintenance management 3. Maintenance planning 4. Maintenance strategy 5. Reliability management 6. Quality management and the reliability centred maintenance (RCM) process On completion of the data collection, the data was thoroughly validated to verify that the information is relevant to the research topic. Each maintenance management division’s data was tabulated based on the response of the individuals and analyzed thoroughly to extract the conclusions of the collected data (Maxwell, 2002). The results of the respondents indicated that proactive maintenance and all aspects thereof is the key to success for improving the reliability of the cold box. Reliability engineering management is essential for the stability of the cold box. , M.Phil. (Engineering Management)
  • Full Text:

Applying the predictable maintenance approach to DC traction substations in South Africa

  • Authors: Sprong, Willem
  • Date: 2010-03-10T06:20:01Z
  • Subjects: Reliability (Engineering) , Electric railroads substations , Electric substations
  • Type: Thesis
  • Identifier: http://ujcontent.uj.ac.za8080/10210/383805 , uj:6651 , http://hdl.handle.net/10210/3058
  • Description: D. Ing. , This dissertation deals with the important issue of reliability management for 3kV DC Traction Substations used by the national railway company in South Africa. Maintenance is one of the critical and most costly phases in the lifecycle of any plant. It looks at the total life cycle of the equipment in a typical substation, but the focus in the latter chapters is on the maintenance. Through improved maintenance management, the reliability of the system can be improved. The approach to maintenance is addressed as a predictive strategy, avoiding even more costly nonproductive time due to downtime caused by failure or induced by maintenance. Condition monitoring and assessment is described as one of the effective tools in the maintenance engineer’s armoury to apply a predictive approach. A direct link between predictable maintenance and reliability is explored. In the definition of reliability, concepts such as time and expected performance can be linked to a predictable delivery of the designed function. In other words, if down time is expected and can be prepared for, it is more acceptable than the unexpected. In essence, the system is still reliable as it performs according to expectation. The concept of predictable maintenance can be applied wider than just the 3kV traction substation. The process of identifying critical equipment, to measure the condition and to take decisions based on the rate of change in the condition can be used in any maintenance environment, even outside electrical. The crucial ingredient to this is to understand that condition monitoring is not based on fixed values, but the rate at which these values change. This is called Fuzzy logic. Can we predict the future? If yes, how accurate will the predictions be?
  • Full Text:

Reliability of an electric motor system

  • Authors: Tang, Chao ran
  • Date: 2012-08-27
  • Subjects: Electric motors -- Reliability , Reliability (Engineering)
  • Type: Thesis
  • Identifier: http://ujcontent.uj.ac.za8080/10210/382149 , uj:3204 , http://hdl.handle.net/10210/6617
  • Description: M. Ing. , The design of electric motor systems as we know it today, is very important and has a direct influence on the reliability of the system. In this dissertation, recommendations in design are given to obtain a reliable electric motor system. This dissertation covers a literature review of reliability engineering, and this is then applied to an electric motor system in order to determine the reliability of the system. This dissertation is divided into five parts: Problem definition, theory and literature survey, economics of reliability engineering, analysis and synthesis of an electrical motor system, conclusions and recommendations. Part I describes the environment of an electric motor system and presents some fundamental concepts of reliability engineering. It emphasizes the importance of reliability analysis in the design of electric motor systems. Part II describes some theory and literature about reliability. It emphasizes some existing reliability analysis methods for development of electric motor systems. The reliability prediction method is very useful for analysis of electric motor systems. The author emphasizes that economics of reliability engineering should be taken into account in the design process in Part III. The analysis of life cycle costs is very important. Life cycle costs (LCC) usually consist of the initial investment, preventive maintenance costs, repair costs and the costs for production losses and outages due to failures and disturbances. Life cycle costing methodology is useful in analyzing the design, reliability and maintenance during trade off of technical systems and equipments. Part IV focuses a specific electric motor system. Some existing reliability analysis methods are used to analyse reliability of electric motor systems. It is highlighted how to improve the reliability of electric motor systems. Some economics considerations are also presented in this section. The main conclusion reached in this dissertation is that failure data feedback, and accurate records are very important for reliability engineering. The author makes some recommendations for reliability of an electric motor system in design. This dissertation may contain direct information from sources indicated generally by. This is however generally contextualized within the main aim of the research. This is the result of specific communication obstacles.
  • Full Text:

Reliability growth management of complex electromechanical systems

  • Authors: Rooney, Alexander Charles
  • Date: 2012-09-04
  • Subjects: Reliability (Engineering) , Engineering - Management , Electromechanical devices - Testing
  • Type: Mini-Dissertation
  • Identifier: http://ujcontent.uj.ac.za8080/10210/369213 , uj:3499 , http://hdl.handle.net/10210/6889
  • Description: M.Ing. , This dissertation proposes a reliability management process for the development of complex electromechanical systems. Specific emphasis is the development of these systems in an environment of limited development resources, and where small production quantities are envisaged. The results of this research will provide a management strategy for reliability engineering activities, within a systems engineering environment, where concurrent engineering techniques are used to reduce development cycles and costs. In order to implement a successful reliability engineering and growth management process, the following objectives need to be met: To ensure that reliability is designed into the system under development by providing reliability design data to the system engineering and development teams. To optimise reliability testing resource expenditure by managing the reliability growth process through a design problem monitoring and solution management process. To ensure that system life-cycle costs are optimised through good reliability design choices. To provide an environment where reliability engineering is a integral part of the system engineering process so as to optimise the rapid development process while keeping development expenditure within acceptable limits.
  • Full Text:

Application of reliability engineering in the chemical process plant, to improve reliability and maintainability of equipment

  • Authors: Mamatlepa, Makgomo Thelma
  • Date: 2017
  • Subjects: Chemical plants - Equipment and supplies , Chemical plants - Equipment and supplies - Maintenance and repair , Plant maintenance , Reliability (Engineering)
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/242393 , uj:24999
  • Description: M.Phil. (Engineering Management) , Abstract: By definition, reliability is the probability that a system (could be equipment, vehicle, machine or even a product) performs its intended function, under specified conditions or environment for a set period of time. The Chemical plant at Company X has been struggling to produce PGM salts in a specified time duration due factors such as equipment failure, process related issues and product quality. This paper addresses the importance and value of reliability engineering to the Company X Chemical plant and reasons for considering reliability engineering more fundamentally in the management of operations and maintenance in the plant. The study focused on production loss; factors that contribute to production loss and reliability theory that can be applied to the plant with special focus on equipment failures. The study achieved the research objectives through an extensive study of literature related to the research topic and implementation of practical research. Practical research was carried out through the collection of empirical data from the day to running of the plant, whereby every production stoppage was captured with causes of the interruption. The study employed qualitative method through review of literature to compare what other authors have discovered about different reliability tools and effective maintenance strategies. A case study method was employed to satisfy the other two objectives whereby data was collected, analysed and interpreted to identify factors that contributes to production loss. The results revealed equipment failures as the main contributing factor to production loss in the plant; this was further broken down to individual vessels to see which ones experience the most failures or have shorter MTTF. The findings of the study revealed further that; in order to improve reliability, availability and maintainability of equipment in the plant, a proper RCM process could add value in the plant. RCM analysis will identify most problematic equipment with most failures, analyse failure modes through FMEA process and suggest maintenance strategies that can be implemented to improve performance of the plant. It is concluded that current corrective maintenance approach in the plant is ineffective because it fails to pre-empt or prevent failures before they occur, instead opting for a more proactive preventative maintenance approach will be cost effective for the company. And that reliability theory should be applied specifically for each plant and not use a holistic approach because plants are unique and operate under different conditions...
  • Full Text:

Reliability engineering of a hospital oxygen supply system.

  • Authors: Nel, Coenrad Marais
  • Date: 2012-09-11
  • Subjects: Reliability (Engineering) , Oxygen - Equipment and supplies
  • Type: Thesis
  • Identifier: uj:10037 , http://hdl.handle.net/10210/7426
  • Description: M.Ing. , This dissertation covers a literature study of the reliability engineering, and this is then applied to the hospital oxygen supply system in order to determine the reliability of the system. The hospital oxygen supply system must comply with international and local legislation, which insists that the reliability of the system must be very high, since it supports life in the hospital. Since there were no previous studies conducted in terms of the oxygen supply system to the knowledge of the author, it definitely opens a new study field for the application of reliability engineering concepts. In the research it was found that no records were kept by the company on the failures occurring with the oxygen supply system. This increased the difficulty to calculate the actual reliability of the supply system. A reliability prediction was done, based on the failure rate data from a database. The reliability prediction of the .system was very low, and possibly not a very accurate prediction of the actual reliability of the system. The author therefore created a reliability calculation program, which calculates the reliability of the system and also keeps, an accurate failure data record on each component of the system. The main conclusion reached with this dissertation is that failure data feedback, and accurate records are a very important factor of reliability engineering. This may influence the company's ability to rectify design changes in their systems, as there is no idea where the failure occurred and how much money value is linked to the failures occurring.
  • Full Text:

The sustainability of life cycle costs in a systems engineering process of a 21st century reliability engineering environment

  • Authors: Maoto, Reboneng Mothupi
  • Date: 2013-05-28
  • Subjects: Sustainable development , Life cycle costing , Systems engineering , Reliability (Engineering) , Value analysis (Cost control) , Engineering economy
  • Type: Mini-Dissertation
  • Identifier: uj:7562 , http://hdl.handle.net/10210/8424
  • Description: M.Phil. (Engineering Management) , With the current global political and economic environments, there is a lot of economic fluctuation and uncertainty in the world markets. This results in the instability of prices for goods and other products. And since we operate in a globalised era, this has a direct impact on the life cycle costs of many systems and products. Experience has indicated that a large portion of the total cost of many systems is as a direct result of activities associated with the operation and support of these systems and products, while the commitment of these costs is based on decisions made in the early stages of the system life cycle (Blanchard, 1990:505 & Blanchard, 2004:24-26). Further, the various costs associated with the different phases of the life cycle of a system or a piece of equipment are interrelated. Thus, in addressing the economic aspects of a system, one must look at the total cost in the context of the overall life cycle, particularly during the early stages of conceptual design and advanced system planning. Life cycle cost, when included as a parameter in the systems engineering process, provides the opportunity to design for economic feasibility. To address these aspects the following questions are answered through the research:  What are life cycle costs and what are the benefits of costing them?  When and where are costs incurred in a systems life cycle?  What are the key variables in establishing life cycle costs?  How can these variables be better defined to ensure that the life cycle costs are sustained through the entire life of a system?  Can the engineering inflation be defined and be used instead of the general inflation rate? Now the challenge is that with the fluctuating economic conditions mentioned earlier, one cannot predict the life cycle costs of a system as closely accurate as is required. The proposed research focused on identifying sustainable measures to ensure that life cycle costs remain relevant through the lifespan of a system or equipment.
  • Full Text:

Management of the diagnosis, specification and execution of concrete repairs for reliability

  • Authors: Bester, Johannes Jacob
  • Date: 2011-02-28T06:08:29Z
  • Subjects: Concrete maintenance and repair , Reliability (Engineering) , Maintainability (Engineering) , System failures (Engineering)
  • Type: Thesis
  • Identifier: uj:7034 , http://hdl.handle.net/10210/3556
  • Description: M. Phil. , Concrete is worldwide the most commonly used construction material and, although concrete is durable when exposed to aggressive conditions, it requires some maintenance. If this maintenance is neglected for a prolonged period of time, intrinsic and extrinsic factors will cause the concrete to degrade necessitating repair and rehabilitation. The correct diagnosis of the root cause of degradation, proper specification of repair materials and quality execution of the concrete repairs all contribute to the reliability of the repairs. The correct management of the repair process is necessary to ensure reliability in order for the structure to be returned to an acceptable state.
  • Full Text:

Case study of preventive maintenance carried out at Sebokeng Hospital in radiology department

Digitalisation for optimisation of railway interlocking tests

  • Authors: Nzama, Sipho Ian Ntokozo
  • Date: 2019
  • Subjects: Railroads , Railroads - Safety measures , Reliability (Engineering) , Railroad engineering , Engineering systems - Testing
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/297348 , uj:32414
  • Description: M.Phil. (Engineering Management) , Abstract: Railway system interlocking testing is highly valued and it is a priority that requires stringent procedures which are guided by rail safety regulations. Historically, interlocking testing required significant protocols and efforts which resulted in expensive resource allocation in the form of personnel, equipment and time. The introduction of new technology can potentially reduce the configuration setup times and automate repetitive testing. This in turn can improve the reliability of the test results, save time and resources. This study highlights modernised technology that proposes a new automated system setup that could improve the testing process as this technology can potentially replace traditional testing methods. The findings of this study prove that; the use of digital technology in railway interlocking testing can significantly reduce the amount of time traditionally spent on this process, digital testing can increase the reliability of the test results and it can save on the required human resources to run the tests. A key additional benefit of the digital system is that it uses Siemens Computer Aided Signalling (SICAS), which is developed to comply with the Safety Integrity Level 4 (SIL4) of the European Committee for Electrotechnical Standardisation (CENELEC) Standard EN 50126 of Railway Applications.
  • Full Text:

A framework for improving pump reliability and availability in air separation industry

  • Authors: Maphosa, Ibo
  • Date: 2017
  • Subjects: Pumping machinery industry , Gases - Separation , Reliability (Engineering)
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/269843 , uj:28671
  • Description: M.Ing. (Engineering Management) , Abstract: The quest for a sustainable Asset strategy is gaining substantial momentum in modern day enterprises, especially in air separation plants where hundred percent process reliability and plant availability is no compromise. In order to achieve such levels of operational excellence and integrity, Asset strategy and equipment maintenance strategy systems must be properly integrated. Although many different maintenance programmes exists in the current industrial domain, unintended downtime due to failures of centrifugal pumps remains a major source of downtime in air separation plants. This phenomenon is investigated here in the context of the implementation of reliability centred maintenance (RCM) framework in air separation environment, based upon the available organisational standards and processes. The main objectives of this study are to identify the factors that affect centrifugal pump reliability and identify the ways to improve the reliability of centrifugal pumps in air separation industry. Two Case studies (plants) in the same company were selected for this research. The case study method was considered the appropriate method for this research. This was based upon the type of the research questions posed and in-depth understanding of business operational processes the method provides to the candidate. Computer Assisted Qualitative Data Analysis (CQADAS) software (ATLAS.ti Version 8) was used to analyse the data from the participants. All the questionnaires that were completed by the participants were loaded into the data analysis software. Data reduction, data coding, grouping and theme generation was accomplished. It was found that effective two-way communication or lack thereof between the plant personnel and the Reliability Engineers affects knowledge sharing and quality of pump strategies. An updated RCM framework and an asset strategy model that was developed provide the clarity and improvement of communication that is required to improve centrifugal pump reliability.
  • Full Text:

Corrugation wavelength fixing mechanism and its relationship to train and track geometry parameters

  • Authors: Balekwa, Bingo Masiza
  • Date: 2017
  • Subjects: Railroads - Maintenance and repair , Mechanical wear , Railroad engineering , Reliability (Engineering) , Electric railroads - Equipment and supplies - Management
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/262890 , uj:27786
  • Description: M.Tech. , Abstract: The wavelength fixing mechanism is studied by correlating natural frequencies of a locomotive wheelset to rail corrugation frequency. The bending natural frequencies of a locomotive wheelset are found to be related to a corrugation frequency at the Belfast to Steelpoort track. Modal analysis was conducted to determine the natural frequencies of the wheelset, and a corrugation frequency was calculated using captured train speeds and measured wavelengths. Due to severe curving forces, corrugation is only on curved track, particularly on the inner (low) rail of the track with wavelengths of 58 mm - 90 mm. Corrugation is understood to have occurred due to wear because there is no discernible metal flow on it at all curves. Concrete sleepers have an influence on the formation and sustaining of corrugation on rails - given the fact that corrugation was only found on curved track supported on concrete sleepers. There is a strong discernible relationship between corrugation wavelengths and train speeds; this is true especially for loaded trains. The train speeds are directly proportional to the wavelengths, whereas the tractive efforts are inversely proportional. This makes sense given the fact that in general, tractive efforts are inversely proportional to train speeds. Reference [1] states that amongst most researches that have been conducted over a century, an increase in corrugation wavelength with increasing train speed is observed. The greater the curve radius, the longer the wavelengths. In order to avoid long-pitch corrugation, the track curve radius should be reduced to less than 400 m, this means smaller radius curves have mostly short-pitch corrugation (wavelength < 80 mm) and large radius curves have mostly long-pitch (wavelength > 80 mm) [2]. There seems to be no discernible relationship between the track gauge deviation and the degree of severity of corrugation. All corrugated curves were found on curves with track gauge deviation, either narrowed or widened. Track curves with corrugation were compared with those that have no corrugation present. Track gauge deviations for curves with no corrugation are significantly less than those of curves with corrugation. This research study also looked at answering some of the common questions, regarding corrugation and its relationship with the environment and terrain.
  • Full Text:

Asset modelling framework for use in computerised physical asset management systems

  • Authors: Henry, C.A.
  • Date: 2017
  • Subjects: Assets (Accounting) - Management , Engineering - Management , Information technology , Reliability (Engineering)
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/269606 , uj:28642
  • Description: M.Ing. (Engineering Management) , Abstract: The objective of the research is to formulate a simplified physical asset modelling framework that is universal to any industry or any asset type, for use in the chosen Computerised Physical Asset Management System (CPAMS) such that it provides the benefit of improved management of physical assets over its lifecycle. The research highlights that there are numerous CPAMS, whether branded as ERPS, CMMS, EAMS or CFMS as example, however the track record of providing organisational benefit given the significant initial and ongoing investment, is limited. The literature review highlights that the configuration of the CPAMS is one of the contributors to limited benefit, where configuration refers to the structuring and organisation of the CPAMS to do that which the user require. One aspect of the CPAMS configuration is the physical asset modelling framework within which the physical assets are recorded in the CPAMS along with its myriad of data, information and various settings. In addition to that which is entered by the user, the processing of various performances and reporting against the asset modelling framework is equally critical. The development of the physical asset modelling framework involved two independent approaches, firstly deriving a framework from literature review of reliability and logistics engineering theory, and secondly, a framework derived from the research of existing industry asset and asset hierarchy naming conventions, standards or frameworks. The theory-derived framework was validated by the existing industry frameworks with the difference that majority of the existing industry frameworks has an additional organisation level in the hierarchy. A single physical asset modelling framework was derived from the nine existing industry frameworks and since this also validated the theory-derived framework, the industry-derived framework was concluded as the universal simplified physical asset modelling framework. A CPAMS is a necessity for the optimised management of physical assets over its lifecycle to achieve levels of sustained performance required by the organisation’s long-term business strategy and real-time operations. A CPAMS has the potential to realise this optimised management, however, and this is to be emphasised, this potential is only realisable when the CPAMS is configured and maintained by skilled asset management professionals having detailed understanding of what is required for lifecycle asset management, and therefore how the CPAMS must enable this management. This research has developed one such critical requirement which is a universal simplified physical asset modelling framework.
  • Full Text:

Strategic incremental reliability through an integrated and business focussed maintenance system - stratified model

  • Authors: Muganyi, Peter
  • Date: 2018
  • Subjects: Service life (Engineering) , Reliability (Engineering)
  • Language: English
  • Type: Doctoral (Thesis)
  • Identifier: http://hdl.handle.net/10210/293940 , uj:31972
  • Description: Abstract: The immense contribution of physical assets reliability and their related maintenance strategies has taken central stage in various asset intensive enterprises. In a lot of ways, the way physical assets are maintained and their ensuing reliability carry a noteworthy bearing on the processes of businesses, and hence, their competitiveness and profitability in the product market. Presently, it is no longer time for strengthening the functional divide of an organization, but a business focused approach is required in formulating operational strategies, that galvanizes key functional strategies that cut across strategic functions such as asset maintenance, finance, logistics and manufacturing. This research study developed a strategic physical asset maintenance model that allows asset intensive businesses to increase their physical assets’ reliability performance through application of a business focused maintenance model. The reliability improvement maintenance model was developed and honed based on the gaps that the prevailing maintenance strategies that are widely applied within the South African manufacturing industries such as Total Productive Maintenance (TPM), Reliability Centered Maintenance (RCM) and World Class Manufacturing Maintenance System (WCMMS) are leaving. The gaps that were identified encompassed: (a) lack of application of Computerized Maintenance Management System (CMMS) to drive towards acquisition of perfect maintenance information, (b) absence of formulation systems for optimized maintenance organizational structures to aid up-surging of reliability performance of physical assets, (c) unavailability of a purposed reliability improvement stratum premised on proactive maintenance, (d) absence of cost efficient maintenance resources allocation through assets criticality optimization, (e) unavailability of a planned reliability sustaining model based on perfect, limited and imperfect maintenance actions, (f) inability to unearth failure causes and provide feedback through the proactive maintenance loop to totally root out failure causes, and (g) lack of inclusion of interactive technology and innovation management as a way to heighten assets reliability. Various maintenance strategies were studied to develop an effective maintenance management model that will assist businesses in their business strategic thrusts. The Integrated and Business Focused Maintenance System [IBFMS] - Stratified model was viewed as the most appropriate maintenance strategic model, as its pursuit is on integrating various maintenance techniques that are feasible and effectual in improving the physical assets reliability and hence, the overall business performance. The components of IBFMS Stratified model that were identified as effectual in reliability amelioration comprised of: (a) Pursuit of proactive maintenance where 87% of survey participants confirmed it as effective (b) CMMS drive to acquire perfect maintenance information whereby 68% of survey respondents signified the relevance of CMMS to acquire perfect information useful for reliability improvement (c) Strategic maintenance organizational formulation to support maintenance activities and whereby 81% of survey participants confirmed as effective in assets reliability increase... , D.Phil. (Engineering Management)
  • Full Text:

Factors that can improve the reliability of the traction motor for the locomotives

  • Authors: Bopape, Thulare Kgaugelo
  • Date: 2018
  • Subjects: Locomotives , Railroads , Reliability (Engineering)
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/393621 , uj:32574
  • Description: Abstract : In recent years, many customers are willing to pay product or service that will last them for a long time without disturbing their day to day run of business. Reliability management for the physical resources has to turn out to be the highly important aspect of running the business, especially in the logistics industry. It is vital for the customer to have a full understanding of the product lifecycle for the purpose of knowing the lifespan of a purchased product. Reliability development is directly linked to the product lifecycle cost (PLCC). Unreliability motor unit causes PLCC to increase and it is affecting the manufacturer’s revenue profits and their reputation. This study presents an approach of identifying factors that increase the reliability of traction motors and reduces its life cycle costs by quantifying the reliability of motor units in the rail environment, collecting data of failure statistics. This stats will be used to determine defect severity and how they affect the overall reliability of the system when components failed. The determination of the quantitative pilot survey was to examine the concept reliability management such as mean time between failures (MTBF), failure rate, projected PLCC for the duration of the warranty period for traction motor of Railway locomotives. Original Equipment Manufacturers are odd to investigate the potential means of dropping PLCC and improve the reliability of the product. Components such as brushes, commutator, brush rings, bearing and winding were identified as the main failures that occur frequently according to the stats collected at company X. Those components were scrutinized using reliability techniques such as Root Causes Analysis (RCA), Failure Mode and Effective Analysis (FMEA) and MTBF to determine the causes and effects of parts failing during their operational period. The risk was measured in the process. The Reliability was defined as the probability that the product or system performs its intended function in a specified time and environmental conditions at without changes its physical characteristics. Reliability can be expressed as the possibility of attainment. It is measured in terms of Mean Time between Failures (MTBF). The definition is broken down into three points which are as follows:  Probability–Consumers expect the probability to be 100 percent. “Useable”  Intended Function –Goods needs to be suitable to carry out its main activity without failing.  Stated Conditions –Goods should be able to withstand environmental conditions without error. The findings reveal that finite training for operators that assemble the motor unit takes places. The periodic inspection must be conducted to prevent failure from occurring. Customers should be included in the reliability management program to educate them on how to use the product efficiently without causing unnecessary faults. Find ways of identifying possible failure can save a lot of time and effort for both manufacturers and endusers. , M.Phil. (Engineering Management)
  • Full Text:

Analysis of factors undermining the reliability of railway track in South Africa

  • Authors: Mukwena, Mulalo
  • Date: 2018
  • Subjects: Railroads - Maintenance and repair , Railroad tracks , Railroads - South Africa - Reliability , Reliability (Engineering)
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/284872 , uj:30782
  • Description: M.Phil. (Engineering Management) , Abstract: Various factors have been highlighted as causes of reliability deficiency for railway track, globally. It is rather opaque as to which of these factors are prevalent in the South African railway industry. The study develops a framework for identifying and classifying causes of reliability deficiency for Railway Track (also referred to as Permanent way Infrastructure). The researcher employed the exploratory sequential mixed methods; a qualitative research in a form of structured interviews was conducted and the subsequent results were used to build a quantitative research survey through which, the researcher solicited responses from 52 respondents. Target respondents were mainly engineers, project managers, and Technicians experienced in the management of Railway infrastructure. Findings reveal that Poor maintenance policies, strategies and implementations is the most pervasive factor causing reliability deficiency of railway Track in South Africa whilst, Insufficient funding and Aging rail network became the second and third prevalent factors, respectively. The research also concluded, among other things, that; Track components used in South Africa are as good as those used by other major railway organizations globally. The study recommended that; railway organizations in the country should priorities the replacement of old infrastructure, adequate funding should be made available for construction of new railway lines, maintenance and rehabilitation projects, and as part of continuous improvements, railway organizations should realign and modernize their maintenance strategies and implementations.
  • Full Text:

Challenges affecting the reliability of diesel locomotives within the South African railway industry

  • Authors: Dibakoane, Kgothlelelo Collet
  • Date: 2013-11-25
  • Subjects: Diesel locomotives - Reliability , Railroads - Dieselization , Reliability (Engineering)
  • Type: Thesis
  • Identifier: uj:7789 , http://hdl.handle.net/10210/8683
  • Description: M.Phil (Engineering Management) , The importance of an effective maintenance programme cannot be over-emphasized because such a programme plays such an important role in the effectiveness of lean manufacturing. Maintenance may be considered the health care of any engineering equipment and its equipment. It is required to reduce waste effectively, and to run an efficient, continuous locomotive operation within a business or service operation. The cost of regular maintenance is very small when it is compared to the cost of a major breakdown at which time production is held up. The main purpose of regular maintenance is to ensure that all equipment required for production is operating at 100% efficiency at all times. Through short daily inspections, cleaning, lubricating, and making of minor adjustments, minor problems can be detected and corrected before they become major problems that can shut down a production line. A good maintenance programme requires company-wide participation and support by everyone from top executives to shop floor personnel (Dale, 2008) The function of reliability engineering is to develop the reliability requirements for a product, establish an adequate reliability programme, and perform appropriate analyses and tasks to ensure that the product meets its requirements. These tasks are managed by a reliability engineer who usually holds an accredited engineering degree and has additional reliability-specific education and training. Reliability engineering is closely associated with maintainability engineering and logistics engineering. Many problems from other fields can also be tackled using reliability engineering techniques (O’Connor 2010). Reliability is defined as the probability that a device will perform its required function under stated conditions for a specific period of time, and quality can be defined as how the recipient of the product or service views the product (Barringer, 2006). Therefore the two cannot be viewed differently as they both have the same focus which is the end result of the product’s performance. The findings reveal that customers should form part of reliability management systems; the development of ways to identify possible failure before it actually happens is key in achieving reliability targets; and training of key personnel on engineering and quality department as well as resource planning and utilization is a key towards eliminating reliability challenges.
  • Full Text:

The management of reliability in a multi-level support environment

  • Authors: Wessels, Arie
  • Date: 2012-09-11
  • Subjects: Reliability (Engineering) , Maintainability (Engineering)
  • Type: Thesis
  • Identifier: uj:9947 , http://hdl.handle.net/10210/7344
  • Description: M.Ing. , In this thesis aspects of reliability management in a multi-level support environment are researched. Complex systems are generally supported over a number of support levels due to the specialist nature and support infrastructure requirements of the individual subsystems. Such a support approach also ensures optimum availability of the system whilst the subsystems are still in the repair cycle. Once a new system is put into service, it is exposed to the actual operational environment and not the simulated environment that was used to qualify the system during its development. In the operational environment, the system is also exposed to the support infrastructure. These factors, as well as any latent design and production defects, impair the achieved operational reliability of such a system. False removals and premature failures after a repair action further degrade the actual operational reliability of the system. It is generally not possible to qualify the logistic support infrastructure fully before placing a new system into operational service. Support stabilisation should take place early on in the support phase of such a system to correct all latent defects and deficiencies of any of the logistic elements required to support the system. Any latent design and production process defects not eradicated from the system will also surface during the support stabilisation period. Support stabilisation will ensure a constant failure rate for the operational life of the system at the lowest life-cycle cost. The methodology used to achieve system reliability growth during the support phase is similar to reliability growth during the development phase. However, additional variables of the operational and support environment are now included in the reliability growth process. The process is also further compounded by the geographic separation of the different levels of support each generally with their own support management infrastructure. The proposed approach is: get total management commitment and close the management loop over the different levels of support. establish the root cause of every system failure implement a test, analyse and fix policy eliminate ineffective repair actions ensure that the system operational environment is within the system specification remove latent design defects from the system correct deficiencies in the logistic elements.
  • Full Text:

Improving the reliability of a chemical process plant

  • Authors: Tomo, Zonwabele Zweli Simon
  • Date: 2012-06-05
  • Subjects: Reliability (Engineering) , Plant maintenance - Management , Chemical plants - Equipment and supplies , SASOL WAX , Engineering instruments , Chemical engineering - Safety measures
  • Type: Thesis
  • Identifier: uj:2427 , http://hdl.handle.net/10210/4887
  • Description: M.Phil. , In modern society, professional engineers, technologists and technical managers are responsible for the planning, design, manufacture, maintenance and operation of the processes and systems ranging from simple processes to complex systems. The failure of these can often cause effects that range from inconvenience and irritation to severe impact on the society and its environment. Users, customers and society in general expect that products be reliable and safe at all times (Allan & Ballinton 1992). The biggest investment in any plant is, arguably, on individual plant equipment. It is therefore reasonable to give the greatest attention possible to the health and integrity of equipment that form part of the chemical process plant.Most of plant failures occur without warning and this result in equipment breakdowns, huge production losses and expensive maintenance. The reaction to plant failures has, in most cases, been a reactive maintenance which means that the plant equipment must fail before the cause of fault is investigated and the equipment is repaired. Reactive maintenance has shortcomings in that it is successful in solving problems temporarily but does not guarantee prevention of fault recurrence. Equipment and process failures waste money on unreliability problems. The question that arises is. ‘How reliable and safe is the plant during its operating life?’ This question can be answered, in part, by the use of quantitative reliability evaluation. The growing need to achieve high availability for large integrated chemical process systems demands higher levels of reliability at the operational stage. Reliability is the probability of equipment or processes to function without failure when operated correctly for a given interval of time under stated conditions. This research dissertation is aimed at developing equipment optimisation program for the chemical process plant by introducing a logical approach to managing the maintenance of plant equipment. Some relevant reliability theory is discussed and applied to the Short – Path Distillation (SPD) plant of SASOL WAX. An analysis of the failure modes and criticality helps to identify plant equipment that needs special focus during inspection.
  • Full Text:
  • Disclaimer
  • Privacy
  • Copyright
  • Contact