Inventory parameter management and focused continuous improvement for repetitive batch manufacturers

What this thesis proposes is a methodology to assist repetitive batch manufacturers in the adoption of certain aspects of the Lean Production principles. The methodology concentrates on the reduction of inventory through the setting of appropriate batch sizes, taking account of the effect of sequence dependent set-ups and the identification and elimination of bottlenecks. It uses a simple Pareto and modified EBQ based analysis technique to allocate items to period order day classes based on a combination of each item's annual usage value and set-up cost. The period order day classes the items are allocated to are determined by the constraints limits in the three measured dimensions, capacity, administration and finance. The methodology overcomes the limitations associated with MRP in the area of sequence dependent set-ups, and provides a simple way of setting planning parameters taking this effect into account by concentrating on the reduction of inventory through the systematic identification and elimination of bottlenecks through set-up reduction processes, so allowing batch sizes to reduce. It aims to help traditional repetitive batch manufacturers in a route to continual improvement by: Highlighting those areas where change would bring the greatest benefits. Modelling the effect of proposed changes. Quantifying the benefits that could be gained through implementing the proposed changes. Simplifying the effort required to perform the modelling process. It concentrates on increasing flexibility through managed inventory reduction through rationally decreasing batch sizes, taking account of sequence dependent set-ups and the identification and elimination of bottlenecks. This was achieved through the development of a software modelling tool, and validated through a case study approach.

A survey of continuous improvement practices in the United Kingdom and Mexico

With the advent of globalisation companies all around the world must improve their performance in order to survive. The threats are coming from everywhere, and in different ways, such as low cost products, high quality products, new technologies, and new products. Different companies in different countries are using various techniques and using quality criteria items to strive for excellence. Continuous improvement techniques are used to enable companies to improve their operations. Therefore, companies are using techniques such as TQM, Kaizen, Six-Sigma, Lean Manufacturing, and quality award criteria items such as Customer Focus, Human Resources, Information & Analysis, and Process Management. The purpose of this paper is to compare the use of these techniques and criteria items in two countries, Mexico and the United Kingdom, which differ in culture and industrial structure. In terms of the use of continuous improvement tools and techniques, Mexico formally started to deal with continuous improvement by creating its National Quality Award soon after the Americans began the Malcolm Baldrige National Quality Award. The United Kingdom formally started by using the European Quality Award (EQA), modified and renamed as the EFQM Excellence Model. The methodology used in this study was to undertake a literature review of the subject matter and to study some general applications around the world. A questionnaire survey was then designed and a survey undertaken based on the same scale, about the same sample size, and the about the same industrial sector within the two countries. The survey presents a brief definition of each of the constructs to facilitate understanding of the questions. The analysis of the data was then conducted with the assistance of a statistical software package. The survey results indicate both similarities and differences in the strengths and weaknesses of the companies in the two countries. One outcome of the analysis is that it enables the companies to use the results to benchmark themselves and thus act to reinforce their strengths and to reduce their weaknesses.

Using simulation to assess the introduction of technology in a continuous operations process

Purpose – To investigate the role of simulation in the introduction of technology in a continuous operations process. Design/methodology/approach – A case-based research method was chosen with the aim to provide an exemplar of practice and test the proposition that the use of simulation can improve the implementation and running of conveyor systems in continuous process facilities. Findings – The research determines the optimum rate of re-introduction of inventory to a conveyor system generated during a breakdown event. Research limitations/implications – More case studies are required demonstrating the operational and strategic benefits that can be gained by using simulation to assess technology in organisations. Practical implications – A practical outcome of the study was the implementation of a policy for the manual re-introduction of inventory on a conveyor line after a breakdown event had occurred. Originality/value – The paper presents a novel example of the use of simulation to estimate the re-introduction rate of inventory after a breakdown event on a conveyor line. The paper highlights how by addressing this operational issue, ahead of implementation, the likelihood of the success of the strategic decision to acquire the technology can be improved.

The mechanics of the conform continuous extrusion process

The work describes the programme of activities relating to a mechanical study of the Conform extrusion process. The main objective was to provide a basic understanding of the mechanics of the Conform process with particular emphasis placed on modelling using experimental and theoretical considerations. The experimental equipment used includes a state of the art computer-aided data-logging system and high temperature loadcells (up to 260oC) manufactured from tungsten carbide. Full details of the experimental equipment is presented in sections 3 and 4. A theoretical model is given in Section 5. The model presented is based on the upper bound theorem using a variation of the existing extrusion theories combined with temperature changes in the feed metal across the deformation zone. In addition, constitutive equations used in the model have been generated from existing experimental data. Theoretical and experimental data are presented in tabular form in Section 6. The discussion of results includes a comprehensive graphical presentation of the experimental and theoretical data. The main findings are: (i) the establishment of stress/strain relationships and an energy balance in order to study the factors affecting redundant work, and hence a model suitable for design purposes; (ii) optimisation of the process, by determination of the extrusion pressure for the range of reduction and changes in the extrusion chamber geometry at lower wheel speeds; and (iii) an understanding of the control of the peak temperature reach during extrusion.

Achieving continuous improvement through self-assessment

In 2007 the UK Office of Government Commerce was mandated to carry out Procurement Capability Reviews (PCR) across the 16 top spending UK Government Departments. Since then, this programme has evolved into a self assessment based approach which is markedly different from the original approach. Will the move from a centre-led strategic review of procurement capability to a department-led model based on self assessment continue to strengthen and improve procurement capability across Central Civil Government? OGC is currently working with UK Government Departments to carry out their PCRs using a self-assessment tool which incorporates qualitative and quantitative measures. Results are generated based on a capability maturity model. The results are assured independently. OGC expectations are that tangible and measurable capability improvements will be realised when departments embed the self-assessment model and implement the findings as part of a continuous improvement regime. This paper is a case study, using some relevant literature to reflect on past and possible future development of the PCR self assessment scheme.