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The well-operating condition of journal bearing is the assurance to keep superior performance of water-lubricated twin-screw compressor. To design the journal bearing more reasonably for this type of compressor, this paper aims to study the effects of rotating speed and design parameters on bearing characteristics, considering surface roughness and bending deformation of the shaft at the same time.

The average Reynolds equation considering the effect of surface roughness is adopted and solved by finite difference method and successive over-relaxation method to calculate pressure distribution with real bearing shapes and boundary conditions. The bending deformation of the shaft is calculated using simply supported beam model of variable cross-section.

The dynamic lubrication characteristics of four water-lubricated journal bearings in twin-screw air compressor are calculated and analyzed. In addition, the static characteristics of journal bearing including friction coefficient, film thickness ratio distribution and water film pressure distribution are calculated numerically with different rotating speed and design parameters. Moreover, some design principles of water-lubricated bearing for twin-screw compressor are put forward.

The lubrication characteristics of the water-lubricated journal bearing in twin-screw air compressor are calculated considering surface roughness and bending deformation of the shaft at the same time. The paper’s results may provide design guidelines for journal bearing in this kind of twin-screw compressor.

HARDLY had the dispute at BL ended and the men had gone back to work amidst universal rejoicing (apart from the more militant of the shop stewards) than several hundred of them had to be sent back home, rightly on full pay, because of a plague of fleas that had invaded the factory. Talk about scratching for a living…!

This study aims to develop a new method to treat the numerical singularity at the critical nodes of two skew coordinates, and optimize the leakage of micro herringbone grooved journal bearings (MHGJBs) with this method.

A side leakage numerical algorithm is proposed by using the skew meshes with a virtual node (SMVN) method to evaluate the effects of groove angle, bank/groove ratio, groove depth and groove number on load capacity, friction and side leakage of MHGJB.

The SMVN method is effective in treating the numerical singularity at the critical nodes of two skew coordinates. Besides, a group of optimized parameters of micro herringbone groove is obtained which can not only minimize the side leakage but also improve the load capacity and friction force.

A virtual node method was proposed, which can significantly improve the calculation accuracy in the side leakage model.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. 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 the 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 material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

IT was only a very few years ago that computers came into fashion, as it were. Firms, unfortunately denied the benefit of foresight, vied with each other in being the first in their respective fields to own a computer.

The research establishment moved last year from its previous location at Bracknell, following the sale by Burmah of Edwin Cooper & Company Limited, joint occupiers with Castrol of the Bracknell laboratories, to the Ethyl Corporation of America.

AT regular intervals the Ministry of Labour Gazette publishes statistics of labour turnover on an industry‐wide basis from which certain generalisations may be drawn. On the whole, however, it is an industrial burden about which very little detailed information is available. Its causes have been variously ascribed to such factors as the level of employment and the chances of alternative work.

Cray Valley Products Ltd. (head office and technical service laboratories) have moved to Farnborough, Kent BR6 7EA. Tel. Farnborough 53311.

In the continuing endeavour to work towards ever better management, the project manager has a crucial role to play. This monograph assesses the requirements of project management in terms of training and experience, demonstrates what sort of person the project manager should be, and also the role that should be played by the project team. In order to illustrate the manner in which the essential qualities in both the project manager and his team are displayed in action a number of completed projects worldwide are reviewed. Both successful projects and disastrous projects are used to demonstrate the way in which the problems encountered in real life can be met and overcome. In conclusion both the prospects and the problems that the future may hold for the project manager are assessed.

BASF Lacke + Farben AG, Muenster (Federal Republic of Germany) and Tanabe Chemical Industries Co Ltd., Osaka (Japan) have established a joint company for the sale of OEM automotive paints. THe agreement was signed in Osaka by Hrimata Tanabe, President of Tanabe Chemical Industries, and Dr Juergen F Kammer, member of the Board of BASF Lacke + Farben AG.