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The purpose of this paper is to study the pressure response characteristics of the cartridge electromagnetic relief valve, which offers the problems caused by low pressure response and low efficiency in hydraulic plate shearing machines.

First of all the mathematical model of the cartridge electromagnetic relief valve is deduced to analyze the influence of the relevant parameters on the system pressure response. Then experiments are conducted to research the dynamic characteristics on building and relieving pressure. Through comparison of theoretical and experimental research, the results are found.

The results show that the input flow, working pressure, diameter of adjacent damping hole, and spring stiffness of the main valve have great influence on building pressure of the system, and have no influence on relieving pressure, while diameter of damping hole of control cover plate has influence on the building and relieving pressure of the system.

The research results provide powerful theoretical support for the parametric design of the cartridge electromagnetic relief valve in the hydraulic system of plate shearing machine.

THE Electronic Computer Exhibition and the B.I.M. conference have provided material for serious contemplation. Sir Harold Gillett, Lord Mayor of London, opening the Exhibition suggested that we are living in the age of the second industrial revolution. There are some who share the Lord Mayor's view and others who take the whole matter in their stride. One thing is certain, we shall be able to do more—and do it more efficiently.

Chadderton, England — the home of British Aerospace PLC (BAe), the British company which plays an important role in the Airbus project as designer and builder of the wings for A300, A310, A320 and A340 aircraft. The wings are designed at BAe, Filton, prior to machining at Chadderton, following which assembly is undertaken at BAe in Chester. The company has a one‐fifth share in the Airbus business representing £1 billion turnover and with orders and deliveries for the aircraft approaching 900, the importance of Airbus to the plant is continuing to increase.

This paper gives a review of the finite element techniques (FE) applied in the analysis and design of machine elements; bolts and screws, belts and chains, springs and dampers, brakes, gears, bearings, gaskets and seals are handled. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of this paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An Appendix included at the end of the paper presents a bibliography on finite element applications in the analysis/design of machine elements for 1977‐1997.