Continuous process improvement applied to an engineering education system

The Engineering education is considered to be a system. Most engineering education systems are under pressure to meet the demands set by its government and private industries . While an expensive student throughput increase is possible, continuous improvement of the education system at all levels will be a more feasible and realistic approach. Within the operation management community a multitude of process improvement champions are competing for the attention of managers (or organisaion leaders). Each champion advocates the adoption of thier improvement methodology. Almost all plead that if one can adopt their specific tools or follow a specific way of thinking, all operation problems can be solved. Most managers (leaders) are however still confused to select the best process improvement methodology for their situation or system’s culture. In this research study several process improvement methodologies were evaluated and related to issues in an engineering education system. The objective is to support heads of an engineering education system with strategic operation decisions to meet future demands. Working through the apparent conflicting claims of performance improvement programs, it was found to critical to concentrate on the primary and secondary effects of these programs. Although each improvement methodology can contribute valuable approaches to an engineering education system, it is still found to be a challenge for leaders to define quality education and set targets for continuous improvements. The finding of this study illustrates that the various continuous improvement process methodologies can be utilised at various levels of the engineering education system. In order to fully maximise the effectiveness of the improvement methodology or initiative the system must be transformed from the traditional engineering education system to a more innovative system which includes process improvement as part of its culture

Wear characterisation in milling of Ti6Al4V : a wear map approach

Thesis (PhD (Industrial Engineering))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: Information on the milling of Ti6Al4V is limited; with most studies concluding that it is not possible to obtain a significant increase in the material removal rate (Qw). Tool wear maps can be a diagnostic instrument for failure analysis. Cutting speed (vc), maximum un-deformed chip thickness (heMax) and the radial immersion percentage (ae/Ø %) are the key variables in understanding the milling of titanium alloys. The objective of this research study was to construct tool wear maps for the milling of Ti6Al4V. This will form the foundation of understanding the cutting demands on the tool, in order to analyse the main wear mechanisms. Remedial actions, which are developed by tool suppliers, can be considered and integrated via this understanding of the failure modes and related mechanisms. Firstly, experimental data from background studies, literature and industry on wear rates and wear mechanisms pertaining to the milling conditions was gathered to construct the tool wear map. Mathematical models describing the wear behaviour for these conditions were also investigated. Secondly, work piece failure maps have been superimposed onto the tool wear maps constructed to understand the global failure boundaries. Experimentation was carried out to validate the constructed maps. The tool wear map could then be used to discuss the observed effects and consider remedial actions. Cutting speed corresponds to the magnitude of the thermal load and heMax represents the mechanical load. The ae/Ø % defines the duration of the exposure to the thermal load at the edge of the cutting tool. This investigation has shown the following issues to be of importance when considering tool performance via the tool wear map approach: 1. The key to designing tool wear maps is to identify the most economic Scheduled Replacement Time (SRT) for the specific components. Knowing the correct SRT makes it possible to optimize the milling conditions so that the cutting tool wears gradually under the cutting conditions, and lasts longer than the economic SRT. 2. Increased vc will decrease tool life (TL). However, in low transverse rupture strength tools there may be a minimum vc below which mechanical overload may occur. Similarly, a local maximum TL (a sweet spot) may exist if there is a phase change in the work piece material. 3. Increased heMax will decrease TL. However, heMax must be kept below a maximum critical value to avoid mechanical overload, but above a minimum critical value to avoid work hardening. 4. Increased ae/Ø % will decrease TL. The best balance of high Qw and economic TL is found with ae/Ø between 30-40% for rough milling. In finish milling the radial cut is limited to 1 mm finishing stock of the work piece. This study revealed the following important factors when considering work piece failure in the milling of Ti6Al4V: 1. Increased vc will reduce the cutting resistance of the work piece and increase Qw. However, vc must be kept below a maximum critical value to avoid work piece material burn, but above a minimum critical value to avoid burring and poor surface finish, due to tool build-up and chip jamming. 2. Increased heMax will increase the cutting resistance of the work piece and increase Qw. The heMax must be kept below a maximum critical value to avoid poor surface finish, poor flatness and parallelism (due to work piece bending). Likewise, heMax must be kept above a minimum critical value to avoid work hardening and burring. The constructed tool wear maps are validated with experimental work. This research work identified safe zones to productively mill Ti6Al4V, while producing components with a sufficient surface integrity.AFRIKAANSE OPSOMMING: Inligting rondom freeswerk van Ti6Al4V is beperk en volgens meeste studies is dit nie moontlik om ‗n wesenlike toename in die materiaal verwyderingstempo (Qw) te behaal nie. Snybeitel verwerings kaarte kan ‗n diagnostiese hulpmiddel wees tydens analisering van snybeitels. Snyspoed (vc), maksimum onvervormende spaanderdikte (heMax) en radiale snitdiepte persentasie (ae/Ø %) is die sleutel veranderlikes om die freeswerk van Ti6Al4V beter te kan verstaan. Die doel van die navorsingstudie was om snybeitel verweringskaarte vir die freeswerk van Ti6Al4V te bou. Die werk vorm ‗n fondasie om die eise van freeswerk op die snybeitel beter te verstaan. Sodoende kan die hoof verweringsmeganismes analiseer word. Regstellende aksies wat deur snybeitel vervaardigers ontwikkel is, was ondersoek en integreer met die huidige kennis rondom die falingstipe en verwerings meganismes. Aanvanklik was eksperimentele data van agtergrond studies, literatuur en industrie oor die verweringstempos en -meganismes rondom die freeswerk van Ti6Al4V versamel. Hiermee is verweringskaarte gebou. Wiskundige modelle wat die verwering kan beskryf was ook ondersoek. Daarna was werkstuk falingskaarte integreer met die ontwikkeling van die snybeitel verweringskaarte om sodoende die grense in geheel te verstaan. Eksperimentele werk was gedoen om die snybeitel verweringskaarte se uitleg te toets. Sodoende kon die snybeitel verweringskaarte gebruik word om die gedrag van die snybeitel te bespreek en regstellende aksies te ondersoek. Snyspoed (vc) stem ooreen met die grootte van die termiese lading en heMax verteenwoordig die grootte meganiese lading. Die ae/Ø % omskryf die tydperk van blootstelling aan die termiese lading op die snyrand. Die ondersoek het bewys dat die volgende faktore belangrik is wanneer snybeitel prestasie met die snybeitel verweringskaart evalueer word: 1. Die sleutel tot die ontwerp van snybeitel verweringskaarte is om die mees ekonomies beplande vervangingstyd (SRT) vir spesifieke komponente te identifiseer. Sodoende is dit moontlik om die frees toestande te optimaliseer, waaronder die snybeitels geleidelik sal verweer onder die eise en vir ‗n langer tydperk as die ekonomiese SRT sal kan sny. 2. Toename in vc sal snybeitelleeftyd (TL) laat afneem. Snybeitels met ‗n lae dwarsbreuksterkte, kan ‗n minimum vc hê waaronder meganiese oorlading plaasvind. Terselfdertyd, kan ‗n maksimum TL (‗n ―sweet spot‖) bestaan as daar ‗n fase verandering in die werkstuk materiaal plaasvind. 3. Toename in heMax sal TL laat afneem, maar moet laer as ‗n maksimum- en hoer as ‗n minimum kritiese waarde wees, om sodoende meganiese oorlading en werksverharding onderskeidelik te vermy. 4. Toename in ae/Ø % sal TL laat afneem. Die beste balans tussen TL en ae/Ø % is gevind met ae/Ø % tussen 30-40% vir growwe freeswerk. In afrondingsfreeswerk is die radiale snit beperk tot 1 mm van die oorblywende werkstuk. Die ondersoek het bewys dat die volgende faktore belangrik is wanneer werkstukfaling in ag geneem word met snybeitel verweringskaarte: 1. Toename in vc sal die werkstukweerstand geleidelik verminder en Qw laat toeneem. Ongelukkig is vc beperk tot ‗n maksimum kritiese waarde om werkstukfaling te voorkom weens ‗material burn‘. Die snyspoed moet ook hoër as ‗n kritiese waarde wees om werkstukklitsing en swak afronding weens spaander probleme te vermy. 2. Toename in heMax sal die werkstuk weerstand geleidelik vermeerder en Qw laat toeneem. Die heMax is beperk tot ‗n maksimum kritiese waarde om swak werkstuk afronding, weens die buiging van die werkstuk, te vermy. Terselfdertyd moet heMax hoër as ‗n kritiese waarde wees om werkstukverharding en -klitsing te voorkom. Die saamgestelde snybeitel verweringskaarte was bekragtig met eksperimentele werk. Die navorsingswerk het veiligheidsareas identifiseer om Ti6Al4V produktief te frees, sonder om die werkstukoppervlak krities te beïnvloed

Machine learning in cutting processes as enabler for smart sustainable manufacturing

CITATION: du Preez, A. & Oosthuizen, G. A. 2019. Machine learning in cutting processes as enabler for smart sustainable manufacturing. Procedia Manufacturing, 33: 810-817. doi:10.1016/j.promfg.2019.04.102The original publication is available at https://www.sciencedirect.com/journal/procedia-manufacturingENGLISH ABSTRACT: Machine learning is becoming an increasingly popular concept in the modern world since its most common goal is to optimize systems by allowing one to make smarter use of products and services. In the manufacturing industry machine learning can lead to cost savings, time savings, increased quality and waste reduction. At the same time, it enables systems to be designed for managing human behaviour. This research study used a systematic review to investigate the different machine learning algorithms within the sustainable manufacturing context. The study focuses specifically on cutting processes.https://www.sciencedirect.com/science/article/pii/S2351978919305839Publisher’s versio

The evolution of quality management systems to assist entrepreneurs in incubation clusters

Quality management systems are important for any organization to sustain growth develop technologies and to manage innovation. However, the cost of quality can make it challenging for start-up enterprises to be competitive. South Africa needs to establish successful incubation models that can assist the country's government to reach key economic development milestones. The transformation of quality management systems in these incubation clusters to assist start-up enterprises is still not clearly understood. This paper investigates key elements to define the life cycle position of an incubation cluster and the phases to grow from a start-up to a large corporation. The benefits for centrally managing quality management system (QMS) are also discussed. Data was collected from existing incubators and small businesses in the manufacturing industry Current best practices are highlighted and future work discussed

Improving the R&D process efficiency of the selective laser sintering industry through numerical thermal modeling

CITATION: Olivier, C. M., Oosthuizen, G. A. & Sacks, N. 2019. Improving the R&D process efficiency of the selective laser sintering industry through numerical thermal modeling. Procedia Manufacturing, 33:131-138, doi:10.1016/j.promfg.2019.04.017.The original publication is available at https://www.sciencedirect.com/journal/procedia-manufacturingENGLISH ABSTRACT: The selective laser melting (SLS) industry is a relatively novel industry within the broad spectrum of available additive manufacturing (AM) technologies. As with most developing industries, the primary aim is to develop better quality components at reduced costs, often with a disregard towards efficiency. Resource efficiency is a key component of waste management and ties directly to sustainable manufacturing. In the SLS industry, large quantities of raw material are wasted during the machine calibration stage. Each time a new material is developed for SLS manufacturing a specific set of processing parameters need to be developed in order to ensure that high density, high strength components are produced. This paper investigates the possibility of replacing the current inefficient research and development (R&D) methods with numerical modeling. The fusion process can be simulated in a numerical thermal model using a combination of temperature dependent material properties and heat transfer principles.https://www.sciencedirect.com/science/article/pii/S2351978919304949Publisher’s versio

Suitable clamping method for milling of thin-walled Ti6Al4V components

CITATION: Delport, L. D., Conradie, P. J. T. & Oosthuizen, G. A. 2017. Suitable clamping method for milling of thin-walled Ti6Al4V components. Procedia Manufacturing, 8:338-344, doi:10.1016/j.promfg.2017.02.043.The original publication is available at https://www.sciencedirect.comThe use of Titanium alloys is becoming more widespread in the aerospace, automotive and medical industries due to its favourable mechanical and thermal characteristics. Reducing the number of defective parts will increase the overall efficiency of the machining operation and thereby contribute to a more sustainable manufacturing process. An industry problem where a thin-walled titanium alloy aerospace component has deformed during machining has been identified. The effects of clamping methods during the machining process on the accuracy of titanium parts will be investigated through FEM analysis and experiments.https://www.sciencedirect.com/science/article/pii/S2351978917300495Publisher's versio

Initialising customer-orientated digital transformation in enterprises

Digitisation forms a part of Industrie 4.0 and is both threatening, but also providing an opportunity to transform business as we know it; and can make entire business models redundant. Although companies might realise the need to digitise, many are unsure of how to start this digital transformation. This paper addresses the problems and challenges faced in digitisation, and develops a model for initialising digital transformation in enterprises. The model is based on a continuous improvement cycle, and also includes triggers for innovative and digital thinking within the enterprise. The model was successfully validated in the German service sector

lnitialising customer-orientated digital transformation in enterprises

Digitisation forms a part of Industrie 4.0 and is both threatening, but also providing an opportunity to transform business as we know it; and can make entire business models redundant. Although companies might realise the need to digitise, many are unsure of how to start this digital transformation. This paper addresses the problems and challenges faced in digitisation, and develops a model for initialising digital transformation in enterprises. The model is based on a continuous improvement cycle, and also includes triggers for innovative and digital thinking within the enterprise. The model was successfully validated in the German service sector