Experimental investigation of engine valve train friction considering effects of operating conditions and WPC surface treatment

Reduction in friction ensures fuel economy, control on emissions and durability of components in internal combustion engines. A modern gasoline internal combustion engine was instrumented to determine the friction values at the cam–roller interface considering the effects of surface treatment and engine operating state. A series of tests under different operating speeds and lubricant inlet temperatures were undertaken using both an original surface roller and a Wonder Process Craft (WPC) surface-treated engine roller. The results clearly revealed a substantial reduction in friction magnitude for the WPC surface-treated engine roller in comparison to the original roller while operating under similar conditions, indicating their strong potential for employment in engines. An increase in friction with the rise in temperature was also observed for both types of rollers, whereas increased lubricant entraining velocity due to higher operating speed had the opposite impact. A considerable reduction in frictional drive torque ranging from 8% to 28% was observed by employing the WPC-treated roller in comparison to original/untreated roller at various operating conditions, which signifies the strong potential for employment of WPC surface treatment in the roller/follower valve train engines

Dry Friction Clutch Disc of an Automobile under Transient Thermal Load: A Comparison of Friction Lining Materials

This paper shows the comparison of temperatures produced in a dry friction clutch disc with different materials during a single engagement to assist in clutch plate design and analysis. A study of usage of different materials for friction lining of clutch disc is required, which will provide improved performance and enhanced life. This investigation is modelled mathematically and solved numerically using finite element method. ANSYS® 15.0 is a dedicated finite element package used for determining the temperature distribution across a clutch disc. In the present work, an investigation of a conventionally used harmful friction lining material asbestos is compared with carbon-carbon composite, S2-glass fibre and aluminium metal matrix composite. The transient thermal analysis of a clutch disc with different materials is performed and the temperature distribution on the clutch system is compared. Simulation results indicate that all the values of the temperature obtained from the analysis of aluminium metal matrix are less than those of asbestos based lining material, therefore clutch disc made up of aluminium metal matrix composite will assure the extended service life and the longer stability due to the fact that the temperature responsible for the wear and tear has been reduced. Furthermore, the slipping time is also considered in this investigation

Dry Friction Clutch Disc of an Automobile under Transient Thermal Load: A Comparison of Friction Lining Materials

This paper shows the comparison of temperatures produced in a dry friction clutch disc with different materials during a single engagement to assist in clutch plate design and analysis. A study of usage of different materials for friction lining of clutch disc is required, which will provide improved performance and enhanced life. This investigation is modelled mathematically and solved numerically using finite element method. ANSYS® 15.0 is a dedicated finite element package used for determining the temperature distribution across a clutch disc. In the present work, an investigation of a conventionally used harmful friction lining material asbestos is compared with carbon-carbon composite, S2-glass fibre and aluminium metal matrix composite. The transient thermal analysis of a clutch disc with different materials is performed and the temperature distribution on the clutch system is compared. Simulation results indicate that all the values of the temperature obtained from the analysis of aluminium metal matrix are less than those of asbestos based lining material, therefore clutch disc made up of aluminium metal matrix composite will assure the extended service life and the longer stability due to the fact that the temperature responsible for the wear and tear has been reduced. Furthermore, the slipping time is also considered in this investigation

In vitro evaluation of Cuscuta reflexa Roxb. forthrombolytic, antioxidant, membrane stabilizingand antimicrobial activities

The key purpose of this experiment was to evaluate the thrombolytic, antioxidant, membrane stabilizing and antimicrobial potentials of crude ethanol extracts (CEE) of whole plant, organic and aqueous soluble fractions (OF & AQSF). CEE showed the highest (44.63%) clot lysis activity compared to streptokinase (64.35%). In DPPH study, petroleum ether soluble fraction (PSF) has exhibited IC50 of 18.83 μg/mL while the standard ascorbic acid was 2.48 µg/mL. AQSF profoundly inhibited the lysis of erythrocytes (66.20%) which was insignificantly different (p > 0.05) to acetylsalicylic acid (71.98%), the reference. However, AQSF showed a significantly stronger level of protection against heat-induced hemolysis (64.80%) as compared with the acetylsalicylic acid (78.90%). CEE, OF and AQSF have displayed reasonable growth of inhibition of tested bacteria compared to negative control and standard drug (77.50 mg of GAE/g)

Technique developed to study camshaft and tappet wear on real production engine

Purpose This paper aims to present a technique that has been developed to study the wear in the camshaft and tappet. The engine manufacturers use the most suitable materials, lubrication additives and surface coatings to minimize friction in all the components of the engine. Reduced friction results in less wear of critical engine components. The researchers are constantly trying to find an improved lubrication formula which reduces the wear and friction coefficient at a considerably low price. In this regard, the cam follower interface is of much importance because most of the wear occurs in this interface. Design/methodology/approach The tappets and the cam lobes are analyzed to determine wear. A two-dimensional optical surface profilometer is used to measure the tappet wear, and a high-resolution linear variable differential transformer is used for the measurement of cam lobes. Tests are conducted on Mercedes Benz engine OM 646 under constant camshaft speed, constant inlet lubricant temperature and constant lubricant pressure to study the oil rheology on cam tappet wear. Findings The results show that the wear occurs on the cam tappet interface, which is almost a linear phenomenon, and it increases with use

Benefits of wonder process craft on engine valve train performance

The performance and durability of tribological components in roller follower valve train is governed mainly by the roller rotational behaviour. Pure rolling of roller on the camshaft surface is essential to achieve the optimum valve train efficiency. The increase in roller slip can lead to high valve train power loss due to increase in sliding friction and can increase the wear rate of mating surfaces of camshaft and roller. In this research work, a modern gasoline engine having end-pivoted roller finger follower valve train configuration has been instrumented to investigate the effects of Wonder Process Craft surface treatment on roller slip. Comprehensive test programme has been undertaken at transient camshaft speeds by employing the New European Drive Cycle under different oil temperatures and pressures. Remarkable reduction in roller slip was recorded for Wonder Process Craft surface treated roller as compared to the original unmodified roller indicating its strong potential of employment in engine valve train. The test rig, surface treatment of roller, instrumentation, experimentation, results and discussion have been presented in detail in this paper

Benefits of wonder process craft on engine valve train performance

The performance and durability of tribological components in roller follower valve train is governed mainly by the roller rotational behaviour. Pure rolling of roller on the camshaft surface is essential to achieve the optimum valve train efficiency. The increase in roller slip can lead to high valve train power loss due to increase in sliding friction and can increase the wear rate of mating surfaces of camshaft and roller. In this research work, a modern gasoline engine having end-pivoted roller finger follower valve train configuration has been instrumented to investigate the effects of Wonder Process Craft surface treatment on roller slip. Comprehensive test programme has been undertaken at transient camshaft speeds by employing the New European Drive Cycle under different oil temperatures and pressures. Remarkable reduction in roller slip was recorded for Wonder Process Craft surface treated roller as compared to the original unmodified roller indicating its strong potential of employment in engine valve train. The test rig, surface treatment of roller, instrumentation, experimentation, results and discussion have been presented in detail in this paper. </jats:p

Technique developed to study camshaft and tappet wear on real production engine

Purpose This paper aims to present a technique that has been developed to study the wear in the camshaft and tappet. The engine manufacturers use the most suitable materials, lubrication additives and surface coatings to minimize friction in all the components of the engine. Reduced friction results in less wear of critical engine components. The researchers are constantly trying to find an improved lubrication formula which reduces the wear and friction coefficient at a considerably low price. In this regard, the cam follower interface is of much importance because most of the wear occurs in this interface. Design/methodology/approach The tappets and the cam lobes are analyzed to determine wear. A two-dimensional optical surface profilometer is used to measure the tappet wear, and a high-resolution linear variable differential transformer is used for the measurement of cam lobes. Tests are conducted on Mercedes Benz engine OM 646 under constant camshaft speed, constant inlet lubricant temperature and constant lubricant pressure to study the oil rheology on cam tappet wear. Findings The results show that the wear occurs on the cam tappet interface, which is almost a linear phenomenon, and it increases with use. Originality/value Customized jigs were made to measure wear of camshaft and tappet. </jats:sec

Highly Active and Reusable Kenaf Cellulose Supported Bio-Poly(hydroxamic acid) Functionalized Copper Catalysts for C–N Bond Formation Reactions

Distinctly active poly(hydroxamic acid) anchored copper (Cu) catalysts were synthesized from chemically modified kenaf cellulose. They were characterized by Fourier transform infrared spectroscopy (FT-IR), field emission scanning microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), inductively coupled plasma atomic emission spectrometry (ICP-AES), UV-vis spectroscopy (UV), and X-ray photoelectron spectroscopy (XPS). The Cu-catalysts were successfully applied to the Michael addition reaction of amines with α,β-unsaturated carbonyl/cyano compounds and to the Click reactions of organoazides with alkynes under mild reaction conditions. The catalysts enabled excellent yields (88% to 95%) in both of the C–N bond formation reactions and showed easy recycling with outstanding reusability for seven cycles without any distinguished decrease in their catalytic activity