Viscosity and flow properties of multigrade engine oils

Brendel H. Tribotechnical behaviour of non-metallic slideway material on machine tools Hill E.C. and Kleist H.U. Microbial degradation of straight lubricant and hydraulic oils yon Dollinger L. Investigation of the air uptake and air release tendency of lubricating and hydraulic fluids

Cichelli A.E. Selection, performance and lubrication of steel mill bearings

Bauer K. Design of bearings for reliability and small energy losses

Benktander S. A new concept of wheel bearing arrangement design

Schulz H. Interaction of gears and lubricants in vehicles

Butenschon H.-J. Integration of Reynolds equation and calculation of nonsteadly loaded radM plain bearings

Fodor J. and Kolimar G. Examination of the tribological properties of commercial vehicle engines and control gears under working conditions

Rougier P., Barquins M. and Courtel R. Investigation on wear of rubber

Aubert F. Friction behaviour of polyacetal microbearings for watch industry and microtechnics

Treheux D., Godet J.F. and Guiraldenq P. Treatment of 'alloys by internal oxidation for improving the resistance to seizure

Rymuza Z. Lubrication and wear of precision pivot thermoplastics-based bearings

Hintermann H.E. and Perry A.J. Chemical vapour deposition (CVD) applied in tribology

Dotre E. Solution for wear problems with tool and machine elements by application of oxide ceramics

Jantzen E. Research about wear and early damage detecting in aviation

Konig W. and Bierlich R. Functional cooling lubrication as prerequisite for economic grinding

Constantinescu V.N. On the design of fluid film bearings operating at large Reynoldsnumbers Noack G. and Spiegel K. Elastohydrodynamics in radial slide bearing, calculation of carrying power with low gap width Dowson D., Economou P. and Baker A.J.S. The influence of ring dynamics upon the lubrication of piston rings

Thiele E. Results of measurements obtained on a novel piston friction test stand Gehrig J., Fornallaz P. and Regnault G. Tribological behaviour of precision engineering journal bearings under unlubricated friction conditions Durr F. Plastics reinforced by glass as materials for precision engineering bearings

Pawelski O. Solved and unsolved tribological problems in plastic forming of me tals Schey J.A. and Myslivy R.E. The effect of die surface finish on lubrication in ring upsetting de Gee A.W.J. and Begelinger A. Abrasive wear of bearing materials

Hermann P., Thoenes H.W. and Bauer K. Interaction of aqueous lubricants with rolling bearings

Kleinlein E. and Brendel L. Performance of rolling bearings lubricated for life at elevated temperatures Lang O.R. Fatigue of plain bearings; experimental results and calculation methods Hilgers W. Fatigue strength of plain bearing materials based on lead, tin and cadmium Stehr W. The greasing of high charged plastic bearings in precision engineering Huber A. Determination of an agingnumber with IR-spectoscopy suitable for small quantities of lubricating oils

Schaller F. Lubricant supply without foreign particles Lennartz R. Criteria for selection of filters for circulation of lubricants and emulsions Rodermund H. Tribological aspects for selection of friction and antifriction bearings

Massin M. Improvement of tribological properties of plastics by influencing the surface properties Merz H. Improvement of the load capacity of steel/sapphire sliding bearings Basa Fr. and Safr E. Tribological aspects for optimising heavy duty gears Klepper H. Investigation of gas leakage and temperature of dry slide ring sealing by means of model surfaces Bros J., Jacecki J. and Scieszka S. Tribological problems in friction brakes Chichinadze A.V., Braun E.D., Ginsburg A.G. and Ignatieva Z.V. Prediction of brake performances at the stage of designing

Bankmann G. Rolling bearings for precision mechanics Buschel E. Improved endurance life of small electric motors by fluorinated lubricant s Bartz W.J. Education and advanced training in tribology

Heinke G. Testing techniques in tribology - a critical survey and tendencies Scott D. and Westcott V.C. Ferrography

*Papers were presented at the meeting in English, French or German, with simultaneous translation. Papers in the preprints appear only in the original language. More information from Gesellschaft fur Tribolo~ie, Wilhelmstrasse 126, D - 41 O0 Duisburg (Homberg), West Germany

7- 9 December 1977, Ostfildern, West Germany

Viscosity and Flow Properties of Multigrade Engine Oils Over 250 delegates f r o m 18 c o u n t r i e s a t t e n d e d this i n t e r n a t i o n a l c o l l o q u i u m held at the T e c h n i c a l A c a d e m y Esslingen. A t o t a l o f 24 papers were p r e s e n t e d , 14 in G e r m a n a n d 10 in English. The c o l l o q u i u m p r o g r a m m e p r o v i d e d an a l m o s t c o m p l e t e review o f c u r r e n t t e c h n o l o g y o f m u l t i g r a d e engine oils and their d e v e l o p m e n t to m e e t specific engine r e q u i r e m e n t s . The m a i n topics discussed were: the f u n d a m e n t a l s o f r h e o l o g y ; d e v e l o p m e n t s in engine oil viscosity classifications in the U S A a n d E u r o p e ; physical a n d c h e m i c a l p r o p e r t i e s o f viscosity i n d e x (VI)

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i m p r o v e r s ' cold flow b e h a v i o u r a n d high t e m p e r a t u r e viscosity o f oils c o n t a i n i n g VI i m p r o v e r s ; i n f l u e n c e o f m e c h a n i c a l , t h e r m a l , a n d oxidative stresses; s t a r t a b i l i t y a n d p u m p a b i l i t y ; a n d engine p e r f o r m a n c e o f multi-grade engine oils.

W.J. Bartz

Papers presented* Gairing M. Requirements of internal combustion engines to viscosity and flow properties of engine oils Rumpf K.K. Viscosimetric problems involved in engine oils

TRIBOLOGY international June 1978

Kirschke K. Rheological aspects Muller H.G. Chemical constitution and mechanism of performance of VI improvers Debicki M. Tribological thermodynamic model of viscosity, flow properties and lubricating performance of lubricating oils du Parquet J., Rossi A. and Marcantoni R.F. The influence of the nature of the base oil on shear stability of polymer thickened oils Hubmann A., Kletzl P. and Pass F. Structure of base otis and properties of the multigrade engine oils

Selby Th. W. The development of a viscosity classification system for engine oils Eberan-Eberhorst C.G.A. The SAE viscosity classification system for engine otis: International activities

Eckert R.J.A. The behaviour of macropolymers in solution regarding their application as VI improvers in lubricating oils

Stambaugh R.L. Contribution of VI improver to wear control by multigrade engine oils

Hovemann F. and Starke K. New findings regarding application of hydrocarbon

Field performance multigrade premium diesel oils Bell J.C. and Voisey M.A. Relationship between viscometric properties of engine oils and bearing and ring face wear Vaerman J. Composition effects on multigrade diesel engine oil performance

viscosity controllers in multigrade oils Neudorfl P. Polymethacrylates as VI improvers for multigrade engine oils Revus M., Runa A. and Nater P. Perform-

ance and properties of SAE 10E-40 engine oils containing polymethacrylates and styrene-isoprene-copolymersas VI improvers Denis J., Guichaoua J.L. and Tahon G.

Comparative performances of different classes of VI improvers - Laboratory and engine studies Badiali F. and Gerbatz G.P. Laboratory

tests on viscosity index improvers Nemes N. and Kovacs M. Flow properties

of polymer solutions at high temperatures Bosse J. Experiences of multigrade engine

oils for running-in of internal combustion engines

Jenkinson G.G., Marsden K. and Spiess G.

Langheim R., Muller K. and Wissusek D.

Behaviour of non-Newtonian lubricating oils in nonsteady journal bearings yon Petery C. Influence of viscosity of polymer-thickened engine oils on the cold startability of engines Neveau Ch.G. A study of the significance of monograde and multigrade oils in blow-by-control *The papers have been published in the original language in a bound volume, price DM 98. 00, by Lexica- Verlag, Postfach 2, 7031 Grafenau 1 {Wurtt), Germany

26 January 1978, London, UK

Components Design for Highly Pressure Charged Diesel Engines Although it is well known that the world has suffered, and is still suffering, from the worst economic conditions of recent years, it is perhaps not appreciated by many how great has been its effect on the shipping industry, on which so much o f the world's trade depends. Added to the general economic difficulties resulting from reduced sales, marine diesel engine builders have also had to contend with ever increasing demands made by shipowners for engines which must run more reliably, on lower quality fuel, and with higher powers than ever before. It is not surprising, therefore, that the design of many components for such engines now reaches the very frontiers of current technology, and that tribological problems shoufd feature prominently amongst these difficulties. The Institute of Marine Engineers organised a one day meeting in which current solutions to the most pressing of the problems could be succinctly presented and fully discussed by those currently contending with them. Although the number of delegates was perhaps lower than was hoped, a glance at the affiliations of those present showed that many important and forward looking engine builders and component suppliers were

The problems of introducing fuel into the combustion space of a highly rated diesel engine must not be overlooked, and the paper by Groschel, Marshall and Walker 4 described the difficulties of introducing the right amount of fuel in the right form into the cylinder at the right time. One of the most basic methods of increasing the overall efficiency of a diesel engine is to put more air into the cylinders. The subject of turbocharging is a science of its own, and nearly half of the papers presented at the conference were related to it. To introduce more air into the cylinders, either turbocharger efficiency may be improved, or a 2-stage system inay be employed. In either case, the compressed air must be cooled before entering the cylinders to increase the thermodynamic efficiency of the engine, lzumi and Nomura s reported on current applications of particular types of turbochargers, and Muller 6 on the problems related to the 2-stage system. Cooling of charge air was described by Forbes and Ledoyen 7, thus allowing the entire range of problems to be appreciated. Comments

represented, together with a number o f practically orientated research establishments.

An interesting tribological subject missing from the conference was the design of engine bearings, but despite this, the meeting was of interest to tribologists requiring a wider view of current marine diesel engine problems and their solutions. The informal atmosphere allowed a lively discussion of all the papers, which had often to be cut short by the usual limits imposed by the passage of time.

The engine components adjacent to the combustion space are amongst the first which are likely to suffer from an increase in engine rating. Holt a reported on a computer program developed to analyse the 'strength of materials' problems of pistons and cylinder heads, allowing a rapid estimation to be made of the effects of increasing powers on these components.

P. Economou

Papers presented*

Such increases must be transmitted to the crankshaft, the fatigue loading on which is often the cause of failure. Nishihara and Fuki 2 reported on full size test equipment t6 investigate such problems, and described clearly how the various methods of crankshaft manufacture affect the stresses induced. Perhaps the piston ring of a marine diesel engine is the component operating finder the most severe conditions and whose operation is the least understood. Baker and Economou 3 reported on the latest developments of a practically orientated theory of piston ring lubrication, and the way in which it may be used by engine and piston ring designers.

1 Holt J.S. and Parsons B. Diesel engine component analysis by finite element methods 2 Nishihara M. and Fuki Y. Study on full scale fatigue testing of large crankshafts made of cast and forged steels 3 Baker A.J.S. and Economou P.N. Piston ring dynamics and lubrication 4

Groschel E.R., Marshall W.G. and Walker P.T. Fuel injection criteria

5 lzumi S. and Nomura J. Recent developments and applications of M.E.T. turbochargers 6 Muller R. Application of twin turbochargers in large marine diesel engines 7 Forbes M.K. and Ledoyen M.J. Charge air coolers for large diesel engines *Further in]ormation J?om The Institution o f Marine Engineers, 76 Mark Lane, London EC3R 7JN, UK

TRIBOLOGY international June 1978

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