bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lubrication of reciprocating compressors
Authors: Matthews P. H. D. 
Published: July 2006

AbstractWhen gases with different chemical and physical properties are compressed, the type of lubricant to be used in compressing equipment must be given careful consideration. Basically, this equipment can be categorized as reciprocating or rotary. This paper describes the lubrication of reciprocating compressors. The development of lubricants for use in specific applications, such as the compression of air, natural gas, etc., is discussed in detail. This will include a section dealing with the development and use of screening tests to predict the performance of candidate lubricants, the role of current international specifications, compressor rig tests and field applications. The advantages and disadvantages of mineral oils and synthetic fluids in various applications will also be described in detail.
Perfluoropolyalkylether lubricants under boundary conditions: Iron catalysis of lubricant degradation
Authors: Carré D. J. 
Published: July 2006

AbstractPerfluoropolyalkylether (PFPAE) oils and oil‐based greases exhibit signifcant degradation under boundary lubrication conditions. In the absence of significant concentrations of oxygen, as in the case of spacecraft orbital environments, the degradation mechanism consists of two steps: (1) the initial reaction of the PFPAE molecules with freshly exposed iron to form the Lewis acid, FeF3, followed by (2) the reaction of the FeF3 with unreacted PFPAE molecules, which results in the cleavage of the etherate linkages. The result is an autocatalytic degradation that takes place at temperatures below the onset of thermal decomposition. This mechanistic hypothesis is supported by the following experimental results: (1) The reaction of PFPAE with FeF3 has been shown to give rise to fluorinated‐ketone and acid fluoride ether‐cleavage products that are more reactive than the parent PFPAE molecules and have lower molecular weights and thus poorer lubricating ability. (2) FeFx compounds are formed in the wear tracks of wear‐test components under boundary lubrication conditions. On the basis of these experimental results, poor performance can be predicted for PFPAE oils under conditions in which high temperatures (approximately 350 °C) and freshly exposed metal surfaces are present (i.e., the conditions of boundary lubrication). This prediction is corroborated through wear tests in which the performance of PFPAE is compared to the performance of commercial petroleum‐based and synthetic‐ hydrocarbon lubricants to which lead naphthenate or antimony dialkyldithiocarbamate have been added. The test results confirm the well‐known fact that the antiwear additives are very important to prolonged wear life under boundary lubrication conditions. In addition, the results show that, compared to the other lubricants tested, the PFPAE lubricants do not demonstrate adequate lubrication pevormance. Both the PFPAE degradation mechanism and the fact that soluble antiwear additives are not currently available imply that PFPAE lubricants are not currently suitable for applications in which boundary lubrication conditions exist, especially when high loads are involved.
The mechanisms governing crack and pit formation in steel in rolling sliding contact in aqueous lubricants
Authors: Sullivan J. L. , Middleton M. R. 
Published: July 2006

AbstractThis paper presents the results of an investigation of the fatigue damage of steel surfaces operated in rolling/sliding contact conditions in the presence of water glycol‐based fire resistant fluids. It has been shown that pitting life depends on the relative magnitude of fluid film thickness and the lubrication regime in which the system is operated. A minimum in pitting life is shown to occur in the mixed‐elastohydrodynamic region.Mechanisms for crack initiation, propagation and subsequent pit formation in aqueous lubricants are proposed.
Synthetic fluids for automotive gear oil applications: A survey of potential performance
Authors: O'Connor B. M. , Ross A. R. 
Published: July 2006

AbstractThis paper describes studies of transmission lubricants in an axle efficiency test rig. The test lubricants were evaluated over various temperature ranges, for each of five road load speed conditions. This was done for both truck and passenger car. Three synthetic gear oils were evaluated, based on various combinations of synthetic hydrocarbons, esters, and viscosity improvers, and were compared to conventional SAE 80W‐90 lubricants. All three oils demonstrated improvements in axle eficiency. Also reported are evaluations of seven test lubricants in a high‐temperature, high‐torque test, and results of seal compatibility tests.
Lubricant and additive effects on spur gear fatigue life
Authors: Townsend D. P. , Zaretsky E. V. , Scibbe H. W. 
Published: July 2006

AbstractSpur gear endurance tests were conducted with six lubricants using a single batch of consumable‐electrode vacuum melted (CVM) AISI 9310 spur gears. The sixth lubricant was divided further into four batches, each of which had a different additive content. Lubricants tested with a phosphorus‐type load carrying additive showed a statistically significant improvement in life over lubricants without this type of additive. The presence of sulphur‐type antiwear additives in the lubricant did not appear to affect the surface fatigue life of the gears. No statistical difference in life was produced with those lubricants of different base stocks but with similar viscosity, pressure‐viscosity coefficients and antiwear additives. Gears tested with a 0.1 wt % sulphur and 0.1 wt % phosphorus EP additives in the lubricant had reactive films that were 200 to 400 Å (0.8 to 1.6 μin) thick.
The properties and applications of Perfluoropolyether lubricants
Authors: Caporiccio G. , Flabbi L. , Marchionni G. , Viola G. T. 
Published: July 2006

AbstractThis paper looks at the properties of perfluoroether fluids, in terms of their phyisical and chemical properties and antiwear characteristics. The molecular weight‐, kinematic viscosity‐ and specific gravity‐temperature relationships are given, and the fluids' chemical resistance and compatibilty with plastics and elastomers. Test results for for fluids on lubricity are given, as well as information on PTFE greases.
Synthetic two‐stroke engine oil as a tool of exhaust emission control
Authors: Kovács A. , Olagos D. 
Published: July 2006

AbstractPolypropylene oligomers were used to formulate two‐stroke (2T) engine oil for once‐through lubrication systems, to enhance the exhaust emission characteristics of two‐stroke engines. The oligomers alone are suitable from a stability viewpoint, but must be reinforced with polyol‐ester components to have good load‐carrying capability. Both ash‐forming and ash‐free commercial additive packages can be used to formulate the end‐product. The exhaust stream includes the unburnt portion of the fuel:oil mixture. The lubricating oils formulated on polypropylene oligomer base do not contain polynuclear aromatics, the sulphur‐dioxide emission is due to the sulphur content of the fuel and additive (if any). On a bench test, the hydrocarbon emission was significantly lower using polypropylene oil, in comparison to using a commercial mineral‐oil‐based composition.
The lubrication mechanism in low speed plastic deformation with a synthetic lubricant — infiltration of lubricant into the boundary contact region
Authors: Kataoka S. , Kihara J. , Aizawa T. 
Published: July 2006

AbstractTo investigate and evaluate the micro‐pool mechanism in a mixed lubrication regime using polybutene lubricants, experiments were performed using 1 mm brass sheet, for various surface rough nesses of a work piece and die, lubricant viscosities and extrusion speeds. Systematic study showed that (1) the lower viscosity lubricant is easily squeezed out from the micro‐pools into the flat are a through the troughs between the tool and work piece caused by plastic deformation of work piece, and (2) with decrease in lubricant viscosity and speed, or the larger the tool surface roughness becomes, the more lubricant infiltrates into the tool‐work piece interface, which reduces the actual friction coefficient.
Rheology of synthetic lubricating oils
Authors: Wiślicki Bogdan 
Published: July 2006

AbstractA lubricating fluid's flow characteristics are affected by fluid deformation resulting from the action of mechanical forces: flow resistance, dissipation of mechanical energy, transfer and dampening of mechanical disturbances. These in turn affect the lubricating ability of the fluid through energy absorption, power transfer and other properties. Synthetic fluids can display various thixotropic characteristics and non‐Newtonian effects. In this paper, experimental work on these phenomena are reported.
Properties of synthetic oils derived from waste polyolefins
Authors: Déak Gy. , Bartha L. 
Published: July 2006

AbstractSynthetic oils are mainly used in lubricant compositions meeting strict or special technical requirements. Most synthetic oils presently manufactured belong to three types of oils, i.e. polyalphaolefins (PAO), esters and alkyl benzene derivatives. Elsewhere, the authors have described results obtained in synthesising polyolejin oils starting from olefin mixtures produced by mild thermal degradation of waste polyethylene.1,2 In the present paper, the dependence of the flow properties of polyolefin oils on the average molecular mass of the starting olefin mixture is discussed, and some preliminary results are given on synthesising alkenyl succinic esters and alkyl benzene derivatives starting from the same raw materials obtained from waste polyethylene.
Wear reduction of partially stabilised zirconia by lubrication
Authors: Maurin‐Perrier Ph. , Kapsa Ph. 
Published: July 2006

AbstractLubricants are often used to improve the behaviour of ceramics for tribological applications. In this paper, the case of Zirconia, lubricated with different additive‐containing lubricants, is described, to show the antiwear mechanisms during boundary lubrication of ceramics. It was found that the presence of a lubricant eliminates the surface degradation observed in dry friction (mainly transfers). The use of an ester‐based lubricant is associated with a decrease in wear of the ceramic, while silicone‐based lubricants lead to surface damage.With additives, the formation of an interfacial layer adherent to the ceramic is dependent upon the tribological behaviour of the base alone. If that layer is created, zirconia does not form part of its composition.
Compositional changes in lubricated sliding metal surfaces related to seizure
Authors: Johansson Erik , Hogmark Sture , Nilsson Helen , Redelius Per 
Published: July 2006

AbstractThis paper presents an investigation into the mechanisms of failure in lubricated sliding metal contacts. Reciprocated sliding with cylinder‐on‐disc geometry was performed with three types of lubricants based on polyalphaolefin (PAO) oils and three sets of additives. The normal force and sliding speed were chosen to give partial scuffing or seizure within a few hours. The chemical surface films which form through reactions between additives in the lubricants and the metal surfaces were analysed by scanning electron microscopy and Auger electron spectroscopy, before and after the onset of seizure.It is concluded that all three oils formed a rigid surface film as a result of a combination of chemical and mechanical actions in the contact surface. Seizure was initiated by mechanical fatigue and disruption of the film which exposed the metal surfaces to severe scuffing. It Was Also Noticed that different additives gave different friction and wear properties to the contact system.
Lubrication characteristics of oils and greases applied to ball bearings for use in vacuo
Authors: Seki Katsumi , Nishimura Makoto 
Published: July 2006

AbstractThree experiments were conducted to evaluate the long‐term running performance in vacuo of ball bearings lubricated by a synthetic oil and grease. The first experiment was carried out using ball bearings of a shielded deep‐groove type (no. 6204) filled with a grease containing perfluoropolyalkylether (PFPAE) as a base oil and TFE as a thickener. Tests were done at room temperature in a vacuum of 10−4∼10−5 Pa mainly at a rotational speed of 2,000 r/min under an axial load of 50N. The bearings were successfully run for a period of 24,400 h, which corresponds to 3 × 109 revolutions. About 10% in weight of the grease was lost during the test. An inspection of the running accuracy of the bearings tested showed negligible change. The degradation of the grease inspected by FTIR was found to be negligible. A change in the molecular weight distribution of the grease was not observed during the test. The second experiment was conducted with angular‐contact‐type ball bearings (no. 7204), with retainers impregnated with PFPAE oils. Exploratory work was done using full‐component‐type ball bearings (no. 7204), lubricated by a heat‐cured PFPAE oils, both in vacuo and in an air environment. The bearings were run for 280 h (5.0 × 106 revolutions) in air at a speed of 300 r/min under an axial load of 50 N, but failed to operate afer 25 h (4.5 × 105 revolutions) in a vacuum.
EHL traction and related rheological parameters under high temperature conditions
Authors: Muraki M. 
Published: July 2006

AbstractAn approximate formula is presented for the maximum traction coefficient in EHD conditions, by making some reasonable simplifications of an Eyring fluid model. Experiments are conducted for some mineral and synthetic hydrocarbon oils over a wide range of temperatures. Among the rheological parameters related to maximum traction, the representative stress τ0, is determined from the experimental traction curve while the effective viscosity‐pressure coefficient α is obtained in a high pressure viscometer. When the temperature is raised, α falls and τ0 rises. The behaviour of τ0 for some paraffinic oils follows the Eyring theory while the effect of the dissociation of molecular clusters appears with the naphthenic oils. The increase in temperature causes a reduction in the maximum traction coefficient, which can be predicted with sufficient accuracy by the formula using the rheological parameters expressed as a function of temperature.
Chlorotrifluoroethylene oligomer based nonflammable hydraulic fluid. 1 Fluid, additive, and elastomer development
Authors: Gschweder L. J. , Mattie D. , Syder C. E. , Warer W. M. , van Brocklin C. H. 
Published: July 2006

AbstractA chlorotrifluoroethylene (CTFE) based nonflammable hydraulic fluid for use in the −54 °C to 175 °C temperature range has been developed for use in future aircraft and armoured land vehicles to reduce fire losses and improve survivability. The desired flammability, chemical, and physical properties of a non‐ flammable hydraulic fluid were defined in the 1970s and extensive screening tests were performed to determine the best candidate nonflammable hydraulic fluid basestock. CTFE was selected because it had the best overall properties of all the candidates investigated. Structurelproperty correlation studies were conducted better to understand the behaviour capabilities and limitations of the CTFE basestock. Extensive research and development have been per‐ formed to develop soluble, effective antiwear and antirust additives to improve some of the critical properties of CTFE. A successful formulation utilising a stabilised zinc, containing corrosion inhibitor and a sulphonamide antiwear additive, has been developed which meets all temperature, lubricity, compatibility, and thermal stability requirements. Research was concurrently conducted to develop elastomers and seals compatible with the CTFE fluid. Several materials have been developed which are usable in somewhat limited applications and Viton GLT has been found to be successful for wide temperature range applications. This paper also discusses toxicity studies and results, environmental effects, future plans and applications, and the current military specification, MIL‐H‐53119.
A naphthenic oil of hydrogenated coal tar distil‐ late as a lubricant with low solidification pressure
Authors: Sakai T. , Murakami T. , Yamamoto Y. , Uchiyama H. , Komoto T. , Tezuka T. 
Published: July 2006

AbstractA new type of lubricant, TN, composed mainly of condensed polycyclic naphthenic hydrocarbon rings, was developed from coal tar through a complete hydrogenation process. This oil is characterised by a high pressure‐viscosity coefficient and low solidification pressure.The tribological characteristics of this new oil were investigated in an elastohydrodynamic lubrication regime under sliding, rolling/sliding, and rolling contact conditions. The results for the TN oil were compared with those of several oils of different molecular structures: polyalphaolefin of paraffinic hydrocarbon, and naphthenic and paraffinic petroleum oils. It was found that the TN oil was superior to the other oils tested in its ability to form thick oil films, to reduce wear, to increase the coefficient of traction, and to prolong fatigue life.
Chlorotrifluoroethylene oligomer based nonflammable hydraulic fluid. 2 Hydraulic components' development
Authors: van Brocklin C. H. , Campbell W. B. , Gschwender L. J. , Sharma S. K. , Snyder C. E. 
Published: July 2006

AbstractA requirement for a nonflammable hydraulic fluid was defined in the 1970s to eliminate losses attributable to hydraulic system fires. In order to increase the possibility of success of the nonflammable hydraulic fluid development programme, requirements for compatibility with current hydraulic fluids, seals, and system designs were not established. All previous attempts to develop a compatible nonflammable hydraulic fluid had been unsuccessful. Extensive screening of many chemical classes of candidate base fluids led to the selection of a Chlorotrifluoroethylene (CTFE) oligomer. Considerable hardwarel system development was performed for hydraulic system applications, including development of high‐pressure actuators, pumps, and motors. The major thrust of the programme, a totally new system design, was demonstrated in the Lockheed High Technology Test Bed air craft and in the McDonnell Douglas Aircraft 55.2 MPa (8000 psi) technology ‘Iron Bird’ demonstrator. Possible retrofit applications for current systems include a C135E fireproof brake system and the M1/M1A1 Abrams tank gun mount. This paper also discusses material compatibility requirements, design considerations, and the results of pump testing of the nonflammable hydraulic fluid.
Polymer formation during thermal‐oxidative ageing of aviation turbine oils
Authors: Fuchs Hans‐Joachim , Zeman Alfred 
Published: July 2006

AbstractOligomers/polymers formed during the thermal‐oxidative ageing of ester‐based aviation turbine oils have been investigated, using pentaerythritol tetraheptanoate as a model ester. The principal polymer structures in the primary ageing state were revealed by means of chromatographic and spectroscopic methods. The most probable structures are dicarboxylic acid polyesters with variable amounts of α,ω‐dicarboxylic acids having chain lengths of C2 up to C7 The C7‐branches also contained ester‐bonded hydroxy as well as oxo substituents. Pentaerythritol triheptanoate discarboxylic acid mono esters were active precursors in polymer formation.
Oil soluble polyethers in automotive crankcase lubricants
Authors: Cracknell Robert 
Published: July 2006

AbstractThe evaluation of oil soluble polyethers (OSPs) in fully and semi‐synthetic automotive crankcase lubricants is described. Parameters including viscosity, additive compatibility, lubricity/wear performance, oxidative stability, and piston cleanliness are assessed. It is possible to formulate OSP‐containing lubricants with lower VI improver treatment level, superior viscometric properties, and Noack volatilities to comparable lubricants without OSPs. Data from engine tests and field trials show that semi‐ and fully synthetic lubricants containing OSP possess all the performance advantages of ester‐containing lubricants, with additional benefits in terms of engine and inlet system cleanliness. The results indicate that OSPs have excellent potential as synthetic lubricant base fluids.
Hydrolysis of phosphate‐based aviation hydraulic fluids
Authors: Aberathy S. M. , Laurent J. W. 
Published: July 2006

AbstractHigh‐temperature in‐service failure of phosphate ester‐based aviation fluids is primarily due to acid‐catalysed hydrolysis. The reaction is controlled with epoxides, but careful attention to the other additives is needed to avoid including species which catalyse hydrolysis. From an airline's point of view, water concentration is the critical factor, since it is the only variable that it can control. From a system designer's point of view, minimising fluid temperature should be a goal. Plots relating fluid life to temperature and water level for typical commercial fluids are included.
The lubrication property of LB films of cadmium salt of long chain fatty acids
Authors: Du Zuliang , Zhu Ziqiang , Zhang Jun , Xue Qunji 
Published: July 2006

AbstractIn this paper, the authors have systematically studied the friction characteristics of various Langmuir‐Blodett (LB) films of cadmium salts of long alkyl chain fatty acids. The parameters chosen were the number of layers of LB film, the load, and the sliding velocity. The results showed that there exists a range of numbers of layers for which a kinetic friction coefficient value (uk)as low as 0.02 is obtained. On the other hand, the friction coefficient in‐creased gradually as the sliding velocity increased.
The design of fuel efficient automotive hypoid gear lubricants
Authors: Law D. A. , Rowe C. N. 
Published: July 2006

AbstractSynthesised lubricant base stocks and the performance additives used in hypoid gear lubricants can both be chemically designed to give improved hypoid gear efficiency and, therefore, better vehicle fuel economy than provided by conventional lubricantsIn this paper, the authors review, relative to a widely used SAE 90 grade mineral oil‐based lubricant, the changes in gear efficiency which have been documented using certain classes of synthesised lubricants. These advantages are described in terms of (a) EPA City and Highway Cycle efficiencies, (b) absolute data over a wide temperature range under four selected speed/torque combinations, and (c) absolute changes in inefficiency compared to the mineral oil product.Newtonian and non‐Newtonian fluids have been studied. The bulk oil temperature at which a specific lubricant gives maximum efficiency is dependent on both gear operating conditions and on the chemical composition of the lubricant.
A reaming test for cutting fluid evaluation
Authors: De Chiffre L. , Lassen S. , Pedersen K. B. , Skade S. 
Published: July 2006

AbstractAs an alternative to tapping torque measurement and thread finish evaluation, a reaming test is suggested for the evaluation of the lubricating efficiency of cutting fluids. An investigation was carried out where results from tapping torque measurements were compared with those from measuring torque, feed force, and surface roughness in reaming. Two different tap geometries and two different reamer geometries were used. Technically‐pure aluminium was used as the workpiece material and four laboratory water‐based cutting fluids as well as a commercial cutting oil were investigated.The results show that lubricants have a significant and similar effect with respect to both tapping torque and reaming torque, when tools with straight flutes are used. In reaming, a more comprehensive picture of lubrication can be obtained if torque measurement is accompanied by determination of the surface roughness. In a subsequent investigation, the reaming torque and roughness test was used to evaluate two different water‐based cutting fluids and a neat oil, using austenitic stainless steel as the workpiece material.