bluuebunny/crossref_metadata_2025_split huggingface dataset:
Paper 1: The Measurement of High-Speed Unlubricated Metallic Friction
Authors: Williams K. 
Published: June 2010

There exists a likelihood of using, sometime in the near future, metals sliding together in a normal atmosphere at speeds above those normally encountered in engineering mechanisms today. This has led to the desirability of obtaining information about the properties of such materials under extreme conditions of sliding. In this paper a survey is made of the experimental techniques and apparatus used by previous investigators working in this subject. The advantages and disadvantages of the different approaches adopted by them are discussed, and the reasons for the construction of a pin and disc type of apparatus, of the size described, are outlined. The procedure adopted, for designing a suitable machine for use in the laboratory, capable of yielding the desired information under controlled experimental conditions, is outlined. The requirements of the necessary instrumentation are followed by details of the systems finally used. The apparatus finally developed is fully described and details are given of the experiments conducted. A typical set of results are discussed and the experimental errors assessed.
Paper 6: A Study of the Friction Characteristics of Resin-Bonded Bearing Materials Lubricated by Water
Authors: Hurren D. E. , Midgley J. W. , Pritchard C. 
Published: June 2010

An investigation has been made of the static friction of various resin-bonded fibre materials lubricated by water in a thrust-bearing rig. The static friction of water-lubricated phenolic resin-bonded asbestos materials mated with steel is initially low, μ = 013–0·3. This low friction is consistent with the composition of the bearing surfaces as it lies between that of asbestos and that of resin, on clean steel. On running-in, the static friction of these materials increases substantially to μ = 0·3–0·6. Evidence has been found that this is due to the formation of a surface layer on both the mating surfaces causing adhesion. It is concluded that the layer is thermoplastic in nature. Because of this behaviour static friction measurements in which the mating surfaces are not run-in give an unrealistically low value for the static friction. The suggestion that water is held by surface fibres and hence provides boundary lubrication is not borne out by the present results. Under the test conditions employed the static friction of phenolic resin-bonded materials in which polythene and graphite had been incorporated was not lower than that of the parent materials. This was probably because the friction of polythene itself can be high due to its adhesion to the mating steel, and it is evidently difficult to add sufficient graphite to reduce the friction and yet maintain the physical strength. The static friction of silicone resin-bonded asbestos and polyester resin-bonded cellulosic materials can also be high, probably for the same reason that the phenolic resin materials develop a high friction.
Paper 3: The Effect of the Steelmaking Process on the Life of Rolling Contact Bearings
Authors: Scott D. , Blackwell J. 
Published: June 2010

The rolling-four-ball test, which closely simulates the rolling and sliding experienced in angular contact ball-bearings, has been used to study the influence of the steelmaking process on the rolling contact fatigue properties of steels used for rolling bearings. Commercially available balls, as well as specimens made from conventional En-31 and various special high-speed tool-steels manufactured by different processes, have been compared. Methods of improving steel quality, such as vacuum induction melting, vacuum consumable arc melting and vacuum degassing have been assessed. The same types of steel manufactured by similar methods by different steelmakers have been tested. Significant differences in performance have been found between different types of steel and between the same types of steel manufactured by different processes. Acid material was generally superior to basic material, and vacuum techniques were beneficial. Modifications in the steelmaking procedure which improved material properties gave increased resistance to rolling contact fatigue. The effect of the steelmaking process was found to be similar with all steelmakers. Observations of significance in the study of the mechanism of failure have been made.
Paper 16: Minimum Allowable Oil Film Thickness in Steadily Loaded Journal Bearings
Authors: Martin F. A. 
Published: June 2010

There are various factors limiting the load carrying capacity of a steadily loaded journal bearing operating under hydrodynamic conditions. Two of these factors are considered. (1) Surface finish criterion Bearing and journal surfaces are slightly grooved due to machining processes, and when initial contact is made between the surfaces, it is only made at local high peaks, leaving an idealized effective hydrodynamic oil film at the minimum film thickness position in the bearing. This minimum film thickness at metal-to-metal contact conditions is dependent on the surface finish of the two mating surfaces. (2) White-metal wiping criterion At high-speed operation, the oil film temperature in the region of the minimum oil film position will be high if the bearing is operating with a large eccentricity. A condition can arise where the oil film temperature is sufficiently high to cause local plastic flow of the bearing white metal. This criterion is known as ‘wiping’, and at high speeds it will predominate over the surface finish criterion. These two criteria are used in an analysis which gives guidance to the minimum allowable oil film thickness for journals of various sizes running at various speeds. This gives the bearing designer, using conventional hydrodynamic theory (Ocvirk, Cameron and Wood, etc.), some yardstick to assess whether or not his calculated minimum oil film thickness figures are satisfactory.
Paper 18: Non-Linear Modes of Vibration of a Rigid Rotor in Short Journal Bearings
Authors: Huggins N. J. 
Published: June 2010

An unusual analytical approach to oil whirl is presented. Instead of using linearized equations for the oil forces all the non-linear terms are retained. The complex equations are solved on an analogue computer, and the more important results are given which show the unusual vibration characteristics of an oil film. It is shown that self-sustained oscillations can exist and, with an exciting force, sub-harmonics are likely. Also the frequency of response may be a sub- or super-multiple of the exciting force. Ocvirk's short bearing approximation is used as the basis of the analysis. It is recognized that it has certain deficiencies, and the results are therefore treated as indications and not as accurate predictions. Comparison to other theoretical and experimental work supports the validity of the present analysis.
Paper 4: Some Experiments upon the Behaviour of Hypoid Oils in Heavily Loaded Contacts
Authors: Archard J. F. , Hatcher B. G. , Kirk M. T. 
Published: June 2010

Measurements have been made over a wide range of speed and temperature of the thickness of the oil film between rotating crossed-cylinders of hardened steel lubricated with a hypoid base oil and with the base oil compounded with a range of E.P. additives. These values of the film thickness agree well with those found in previous studies of elastohydrodynamic lubrication. It has been shown that the addition of the E.P. additives has no appreciable effect upon the thickness of the film. It is deduced from these studies that an oil film of appreciable thickness must exist between the teeth of hypoid gears over a wide range of operating conditions; the major mechanism of lubrication in a hypoid gear is, therefore, elastohydrodynamic and the main function of E.P. additives is to prevent the initiation of catastrophic forms of failure by local penetration of this hydrodynamic film.
Paper 13: The Influence of an Intercalated Inorganic Salt on the Frictional Characteristics of Graphite
Authors: Hughes R. I. , Daniel S. G. 
Published: June 2010

In recent years, various workers have attempted to improve the lubricating properties of solid lubricants, particularly at high temperatures, by mixing them with inorganic salts. Since graphite forms interlamellar compounds with a variety of inorganic salts, this presents a convenient means of producing evenly dispersed and reproducible combinations. Graphite reacts with ferric chloride vapour to form such a compound in which ferric chloride planes alternate with the carbon planes in the graphite lattice. Although formed from a hygroscopic salt, the compound is quite stable under normal conditions. The frictional characteristics of this material have been assessed over a range of temperatures using a pin-and-disc-type friction rig. The results have been compared with those obtained using the parent graphite and molybdenum disulphide as reference lubricants. It is concluded that the intercalation of an inorganic salt in the graphite structure can lead to certain improvements in lubricating properties, particularly with respect to the adhesion of lubricant to substrate in dry applications; salts other than ferric chloride may be more suitable for this purpose.
Paper 14: The Effect of Pressure and Temperature on Some Properties of Fluids of Importance in Elastohydrodynamic Lubrication
Authors: Galvin G. D. , Naylor H. , Wilson A. R. 
Published: June 2010

Recent advances in the theory of elastohydrodynamic lubrication have greatly increased the demand for information on the physical properties of lubricants at high pressures. Specifically, the viscosity and density and their variation with temperature and pressure enter directly into calculations of the behaviour of lubricants in loaded contacts, whilst for some experimental techniques the dielectric constant at the appropriate conditions is also required. This paper presents measured values of viscosity at pressures up to 15 000 lb/in2 at 30°, 60° and 100°C, and of density and dielectric constant at pressures up to 50 000 lb/in2 at 20° and 100°C for a series of lubricants including mineral, vegetable and synthetic oils. The use of the Clausius-Mosotti relationship to predict dielectric constants at high pressures is shown to be unsatisfactory, and this is demonstrated by application to capacitance measurements obtained in a disc machine.
Paper 3: Some Properties and Applications of the Platinum Metals and Rhenium
Authors: Darling A. S. 
Published: June 2010

The ability of platinum and certain of its alloys to function effectively as structural materials for long periods in air at temperatures above 1400°C ensures for these materials a remarkable position in a variety of industrial processes. The physical characteristics of the platinum metal group are reviewed in this paper and contrasted with those of the base metal rhenium which is similarly rare and expensive. Rhenium and the refractory platinum metals oxidize rapidly when heated in air and rhodium-platinum alloys are generally employed when prolonged resistance to high temperature creep is required. Dispersion strengthened platinum alloys provide even higher elevated temperature properties. Economic justification for the industrial use of the platinum metal group is not difficult to provide because most processes centre on the unique ability of these elements to perform a specific function. In other instances their employment results in a cheaper and superior product. The applications of platinum in the glass industry are briefly described and an outline presented of the philosophy underlying the development of some new rhenium and platinum alloys. Consideration is given to the characteristics of hydrogen-palladium alloys and to their fuel cell and energy storage applications.
Paper 15: Pure Silicon
Authors: Vodden H. A. , Williams J. L. 
Published: June 2010

The requirements of the semi-conductor industry for manufacturing devices such as transistors and rectifiers have resulted in new standards of purity for certain materials. Ultra-pure silicon is now produced commercially, with impurity levels lower than 1 part in 1010, in single crystal form of high structural perfection. This paper describes such a material, laying particular emphasis on the electrical properties, and describes methods by which it is manufactured commercially. The importance of electrically active impurities, such as boron and phosphorus, is discussed with reference to the p-type and n-type conductivities which are thereby introduced. The necessity for strict control of physical parameters during manufacture is emphasized, and methods used for the evaluation of the essential physical properties such as electrical resistivity and crystal structure are described. Some of the applications of pure silicon are introduced in this paper and the physical basis underlying the use of pure silicon in semi-conductor device manufacture is briefly reviewed.
Paper 12: Carbon
Authors: Adams J. M. 
Published: June 2010

The nature of natural and industrial carbons is described, with some recommendations for designing components, in particular, methods which are available for processing final articles to size without machining. Typical applications are briefly reviewed subdivided under the following headings: mechanical applications; electrical applications; and other industrial applications (in this section the various commercial forms of carbon are also reviewed). The paper concludes with a review of several new forms of carbon which have come into the market in the last few years.
Paper 8: Recent Developments in Engineering Ceramics
Authors: Popper P. 
Published: June 2010

Ceramics in the context of this paper will be considered to be inorganic non-metallic materials which are shaped when in a finely divided form, followed by a high-temperature sintering treatment. A better understanding of the properties of ceramics (e.g. alumina) can be gained by the study of the properties of the material in single crystal form (e.g. sapphire). The properties of different materials can be related to their crystal structure. This scientific pursuit has led to a number of new materials (silicon nitride, Si3N4, and boron nitride, BN). Compared with metals ceramics compete favourably on account of their high strength at high temperatures, good wear and corrosion resistance. Their main drawbacks are brittleness and failure by thermal stresses. The application of new methods of fabrication has been aimed at producing ceramics of high density and to accurate dimensions. The properties of the following materials will be discussed in some detail: alumina, Al2O3; silicon nitride, Si3N4; silicon carbide, SiC; and boron nitride, BN. It will be demonstrated that different methods of fabrication can result in widely differing properties of the same material. Small grain size and high density are essential for good mechanical strength. Methods of joining ceramics to metal will be discussed. Some important applications will be reported and consideration will be given to problems facing the designers.
Paper 4: The Significance of Surge Diagrams
Authors: Marples E. I. B. 
Published: June 2010

The aim of this paper is to show how surge diagrams follow logically from two simple principles: The propagation of pressure waves at the speed of sound, and Joukowsky's law expressing the relation between variations in pressure head and in velocity head. Surge lines are a manner of plotting Joukowsky's law and of showing how energy which is being introduced into a pipe or is being drained from it can be converted from one form into another. Complications can be avoided in drawing surge diagrams by recognizing the truly significant factors. If this is done, most practical problems can be studied with adequate accuracy by simple diagrams. The methods used are illustrated by typical examples from the frequent problem of a power failure in a pumping station. Excessive surge pressures are usually avoided by providing an air vessel or a flywheel, the aim being to stop the column of water gradually and to dampen out the oscillations. Special care is needed in avoiding the formation of voids or air spaces anywhere in the system.
Paper 2: The Velocity of Water Hammer Waves
Authors: Pearsall I. S. 
Published: June 2010

Sudden flow changes in a pipeline cause water hammer waves to be transmitted up the pipe. The magnitude of these pressure waves is directly proportioned to the acoustic velocity. The value of the acoustic velocity depends on the bulk modulus or compressibility of the liquid. It is thus affected by pressure, temperature and gas content of the liquid, as well as by the elasticity of the pipe. For water, considerable data are available on the variation of acoustic velocity with temperature and pressure. These are summarized and it is shown that, whereas temperature causes changes of the order of 1 per cent per 5 degC, the variation due to pressure is negligible except at very high pressures. The presence of free gas causes a considerable increase in compressibility, and it is shown that even as little as 1 part of air in 104 parts of water by volume causes a 50 per cent reduction in acoustic velocity. The damping of the pressure waves, which has an overall beneficial effect, is also greatly increased by the presence of free gas, and data are given on these effects. Solids in liquid have a similar but less drastic influence. Experimental results are given of some tests on two sewage pumping stations in which good agreement was obtained between theory and experiment. The elasticity of the pipe also affects the acoustic velocity and a summary is given of the data available for steel, concrete, and rock-lined tunnels, with different types of pipe fixing.
Paper 6: Water Hammer Effects Due to Branched and Stepped Pipes
Authors: Pearsall I. S. 
Published: June 2010

No direct general solution is possible of the water hammer equations. It is thus necessary to use either iterative techniques on a computer or a graphical method to obtain a solution. Most practical systems are not simple pipelines but have changes in section and branch pipes. The paper shows how it is possible to allow for changes in section and branches in the graphical method for the cases of a valve closure or a pump shut-down. The case of a surge tank with base throttle is also applied to a reservoir-turbine installation. In many cases it is not necessary to carry out the exact calculation as the use of an equivalent system will be sufficiently accurate. For a pipeline with different diameters or wall thickness an equivalent simple pipeline can be used. The various suggestions are reviewed and compared for four valve closure cases. For branch pipes or surge tanks some cases where the branches can be neglected are given. The method of allowing for friction in the graphical method, and the assumptions made, are also mentioned. Two examples are included of comparison between the exact method and an equivalent system, with some experimental results.
Paper 3: Effects of Valve Operation
Authors: Livingston A. C. , Wilson J. N. 
Published: June 2010

In modern pumping installations it is generally considered that the most common cause of water hammer is that due to inadvertent stoppage of the prime mover. However, mal-operation of pipeline valves is a further common source, and if danger from such units is to be avoided a knowledge of their operating characteristics is essential. Valve characteristics can determine, to a great extent, the magnitude of the surges which will be initiated following opening or closing of a valve. By graphical representation it is shown how important proper valve selection and operation can become, when related to the system characteristics. Terminal float valves, pressure reducing valves, etc., are prone to oscillation or ‘hunting’ and, if the valve movement enters into phase with certain multiples of the pipeline period (2 l/a), resonance occurs. The effect of such continuing valve oscillation is illustrated graphically. Check valves are primarily installed in pumping systems to prevent the establishment of the reverse flow which could damage both pump and prime mover. For trouble-free operation it is important that the valve possesses inherent non-slam closing features. The effect of check valve operation with respect to surge is illustrated graphically. If certain basic system parameters are known it is possible to predict how a check valve will perform in a given installation. The results of the application of one such analytical approach are presented, together with full experimental verification.
Paper 1: The Dynamics of Railway Vehicles on Straight Track: Fundamental Considerations of Lateral Stability
Authors: Wickens A. H. 
Published: June 2010

The dynamics of existing railway vehicles on straight track is dominated by motions in the lateral plane commonly referred to as hunting. Hunting is a self-excited oscillation caused by the combined action of the conicity of the wheels and the creep forces acting in the contact plane between wheel and rail. In this paper existing and recently developed theories of the lateral motion of railway vehicles are discussed in relation to experimental work on both models and full-scale vehicles. It is shown that a realistic theory taking into account flexibility between the wheelsets and the frame in the longitudinal, lateral, and vertical directions, and the influence of wheel and rail profiles, yield values for the critical speeds which are consistent with experimental results. The influence of various parameters on stability is discussed and it is explained how railway vehicles can be designed for stable running at high speeds. Examples of suitable choices of suspension and other parameters will be given and experiments carried out in order to verify these concepts will be described.
Paper 18: Flow in a Rectangular Cavity
Authors: Lewis W. E. 
Published: June 2010

This paper briefly describes preliminary work in the investigation of the flow in a rectangular cavity formed in one wall of a square channel. The results of visual studies, carried out on a water tunnel and showing the flow pattern for various depths of a cavity of fixed chord, are described. Also wind tunnel data on pressure loss and noise generation are discussed. The flow patterns found in an annular cavity are also described.
Paper 13: The Development of a Disc Local Heat Flux Meter for Use in Boiler Furnaces
Authors: Northover E. W. , Hitchcock J. A. 
Published: June 2010

This paper describes the development of a meter, employing the radial disc principle, for measurements of the local heat flux to the water/steam tube surfaces of boiler furnaces. The design and material requirements are stated for the meter to operate successfully in the arduous conditions of a combustion chamber. The development of the meter is followed from the initial prototype to the proving of the final design.
Paper 20: Measurement of Sliding Friction and Wear in High-Temperature High-Pressure Water Environments
Authors: Roberts W. H. 
Published: June 2010

A new apparatus is described which enables continuous measurement to be made of the friction coefficient between surfaces sliding under boundary lubrication conditions in high-pressure (2700 lb/in2), high-temperature (up to 350°C) water environments. One specimen is held stationary under load against a moving specimen which may be either continuously rotated or reciprocated, linear rubbing speeds being low (of the order of a few centimetres per second). The design of the test section is such that any one of three geometrical configurations of specimen can be selected: piston-cylinder, journal-sleeve, or crossed-cylinders. The friction force transducers which have been developed for this work are described. Friction and wear results are presented for stainless steel (En 58E) sliding against itself, Inconel X, Nimonic 80A, chromium-plate and Deloro SF40, in the temperature range 20°-325°C.