Previous statistical examination of relevant factors in laser drilling has shown that the focal settings, material thicknesses and drilling ambient pressure had a significant effect on the resultant hole geometry, but left open the question of which combination of factors gives optimum drilling. Consequently, the present work examines the optimum focal settings with material thicknesses at atmospheric and subatmospheric ambient pressures of air and oxygen for different materials. The results obtained show that the optimal setting reduces as material thickness increases at all ambient pressures.
The development techniques for gently transferring bulk mail from one conveyor to another is described in a previous paper (1). This paper describes the further development of those techniques, and a method of establishing specific designs.
The effect of the accuracy of location of cylindrical billets in completely closed cavity dies, on forging loads and product accuracy has been investigated. Aluminium billets with various off-centre locations were forged at room temperature on a 3000 kN hydraulic testing machine. The results indicate that inaccuracies in billet location significantly affect forging load requirements and dimensional accuracy of forgings. An energy method solution is presented to provide accurate load predictions for relatively small off-centre locations of billets.
The effect of die design, billet location, billet volume variation, billet geometry, friction and die expansion, on forging loads and forged dimensions are investigated, for solid cylinders forged in completely closed die cavities. Forging tests were carried out on both a 2000 kN mechanical press and a 3000 kN hydraulic testing machine using BS 080M40 steel and commercially pure aluminium. The results show that the above factors can significantly affect forging load requirements and die cavity filling. They provide a basis of information for commercial development of net-shape or near-net-shape forging processes.
The paper contains details of a study carried out by the author while acting as an academic supervisor in a Teaching Company programme. Firstly, the structure and progress of the Teaching Company Scheme since its inception is reviewed. The study is then reported with the aim of identifying strengths and weaknesses within the programme. The views of the three parties involved in the programme (associates, academics and industralists), have been sought. The work shows that all three parties believe that they have much to gain from participation in the programme and also that account must be taken of a high level of commitment necessary for overall success. Finally, conclusions and recommendations are made which offer all three parties a general policy to adopt for the remainder of the programme.
A non-contacting optical sensor is devised to monitor the position and orientation of a robot end-effector or grasped object within fine limits of accuracy. This enables fine alignment of tools or parts with respect to assembly fixtures, thus rendering precision assembly tasks to be performed in a dexterous manner. The sensor is capable of detecting linear displacements of the order of 5 μm or better and angular misalignments down to 5 seconds of arc. The principle of differential detection is employed which reduces the undesired effects of noise and fluctuations in the source intensity.
This paper presents a simulation study of the system efficiency, in terms of production rate, of automatic transfer lines. A particular type of system, referred to as balanced automatic transfer lines, is considered in the study. In such a balanced automatic transfer line, the stations are considered identical in terms of availability and the buffers are uniformly allocated, and only four system design parameters are involved, namely the number of stations, the identical failure and repair rates, and the uniform buffer capacity. Based upon simulation results, an empirical production rate equation is established by using available optimization techniques for fitting non-linear functions. The empirical relationship is validated using further experimental results. It is shown that this empirical equation can be simply used, with a high enough accuracy in many practical applications, to predict production rates of balanced automatic transfer lines with reasonably wide ranges of system design parameters.
The President describes the relationship between technology and the prosperity of our society, and outlines the essential role of the engineer in contributing to this prosperity. He reviews his career in industry and Government and the key contribution of engineering to the growth, development and commercial success of the oil and petrochemical industry. By means of some case studies he illustrates the role of the mechanical engineer in a process industry.
‘Safety’ is a relative term and has different meanings in different situations. The use of the term ‘safety’ in relation to persons as distinct from damage to operating plant under abnormal conditions is discussed. Examples are given pertaining to an installation involving robots, conveyors and other handling plant where a man-machine interface is required for normal operation. The reliability of devices used to provide safety and the need to keep such devices foolproof is discussed. The paper also discusses the possibility of the creation of hazards by removing power from moving machinery in an emergency.
In this paper the author identifies some of the key skills to be used by industrial sales engineers and recommends strategy and tactics for their success. He gives advice on how to approach different types of buyers, on how to make an effective sales presentation, on the use of different types of questions and on how to close the order.
This case study concerns a mechanical engineer who has strong views on business management. He purchased a small engineering company in Dunedin, New Zealand, and put into practice his managerial philosophies of worker participation in decision-making and profit-sharing. The paper reviews the progress of the company during its first three years and then discusses the options for its future development.
Group Schemes for technologist industrial training were established in the early 1970s on the initiative of the Engineering Industry Training Board (EITB) to help small companies to take sandwich course students for single periods of industrial training. The Group Scheme at Bradford University has provided industrial training places for 40 students on the mechanical engineering course during the last 15 years, and the participating companies have recruited six graduates. Details are given of the operation of the Scheme including recruitment, the provision of basic engineering training, and the response of small companies to changes in grant aid. The provision of grant aid has proved a critical factor in the readiness of a company to take a student. The introduction of Engineering Applications 1 (EAI) and changes in funding from the EITB has altered the Group Scheme from a body offering sponsorship in a collective of small companies to one providing closely monitored training for ‘college-based’ students. The work of the Group Scheme could be improved by giving the EITB responsibility for encouraging engineering training in all industries.
Pressure fluctuations in a hydraulic system may be substantially reduced by cancelling the flow ripple produced by the pump. This paper describes a secondary flow ripple generating mechanism which introduces an equal and opposite flow fluctuation to that generated by the pump. Tests have shown that the mechanism can virtually cancel four harmonics of pressure ripple but success is dependent on an accurate knowledge of the pump flow fluctuation characteristic. This is best determined experimentally. Similar improvements can be achieved using a mechanism in a motor. This has the additional benefit of reducing torque fluctuations. The reduction in gear pump pressure ripple achieved with the mechanism has been shown to reduce overall airborne noise levels from a hydraulic system by as much as 10 dB, although the airborne noise radiated from the pump casing was not affected.
Computer technology has given manufacturers the opportunity to monitor, on-line and in real-time, a wide variety of manufacturing systems. Such monitoring systems have considerable potential for expansion and development but need to take account of the special characteristics of particular manufacturing systems and how the information is to be used to best effect. This paper outlines the use of monitoring in the broad context of manufacturing plant operations and describes the design of a development system that will facilitate research into the effective application and improvement of monitoring systems.
This paper is concerned with the design and development of a low-cost system for applying product information to a target area on the top of a carton passing through a cartoning machine at, typically, 60 cartons a minute. A prototype was designed and built which prints high-quality preprogrammed characters on to a range of carton sizes, can be adjusted in the x, y and z planes and can be fitted to a variety of existing packaging machines.
Through continual improvement in the satisfaction of customer needs and expectations, Japanese manufacturers have set new standards in product specification, quality, and reliability and nowhere more so than in the international automotive markets where there is recognition of best-in-world status. In response to the challenge, manufacturing companies in the West and in particular those with international market perspectives, have initiated a process of change that commits to a different approach to quality. The reinforcement of quality control procedures driven by design specifications to which all manufacturing processes must be made to conform, is being displaced by the need for change in the operation of all functions within the company, including those less obviously associated with quality in the end product. Total quality is a philosophy that lays the ground for revisions to the management of the entire production process and creates the conditions for the establishment of a common purpose.
The interplay between the capability of a company, the pull of a market for its product, and its profitability, is examined on a catastrophe ‘cusp’ diagram.
This paper reviews the development of ‘high tech’ companies in the Cambridge area and examines some of the factors which are believed to have encouraged these developments. It identifies the characteristics which attract able young engineers to work for these companies and points to some lessons which manufacturing industry may learn from the ‘Cambridge phenomenon’.
This paper reports on an investigation based on manufacturing companies in the United Kingdom. The investigation examined various ways in which companies manage their product quality. In carrying out the study three different pieces of work have been undertaken: namely, case studies, two separate postal questionnaire surveys, and the development and testing of a method for helping organizations to focus on their quality-related decisions. The method developed enables an organization to identify the strengths and weaknesses of their approach to quality management. The findings reveal the many different opinions, structures and functions relative to the approaches of manufacturing companies to quality management. Due to the multitude of factors which influence the way a company goes about managing the task it was impossible to identify a general approach. It was, however, possible to evolve a method based on a quality-related decision-making approach, which provides a means for manufacturing companies to assess their ongoing management of quality and relate this to their specific needs.
