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São Paulo, Brazil

Tomanik E.,MAHLE Metal Leve SA | Xavier F.-A.,NAGEL Maschinen u. Werkzeugfabrik GmbH | Zhmud B.,Applied Nano Surfaces Sweden AB
Tribologie und Schmierungstechnik

The present study focuses on effects of triboconditioning on the tribological properties of cylinder liners. Cylinder liners for a production 13L heavy-duty diesel engine were tribocon-ditioned using a Nagel honing machine with a modified honing head equipped with a set of non-abrasive tools in place of the traditional hones. Also, a special organotungstate-doped process fluid was used instead of the honing oil. In order to evaluate the effect of triboconditioning on the piston assembly/cylinder liner tribology, reciprocating friction rig tests and floating liner engine (FLE) rig tests were used. The tests demonstrated significant improvement in the tribological properties of triboconditi-oned cylinder liners. The improvement was attributed to the formation of WS2/C tribofilms at the component surface and a modified surface roughness profile with reduced core roughness (Rk) and peak height (Rpk). Source

Zhmud B.,Applied Nano Surfaces Sweden AB | Tomanik E.,MAHLE Metal Leve SA | Xavier F.-A.,NAGEL Maschinen u. Werkzeugfabrik GmbH
Lubrication Science

Triboconditioning is a mechanochemical surface finishing process developed for improving the tribological properties of mechanical components made of steel or cast iron. The process combines elements of extreme pressure mechanical burnishing of the component surface with a tribochemical deposition of a low-friction anti-wear film of tungsten disulphide (WS2). This allows one to produce, in a single finishing operation, a smoother surface with a significantly reduced coefficient of boundary friction and improved wear-resistance and load-carrying capacity. This study presents results of tribological rig tests carried out with valve train components and cylinder bores that underwent the triboconditioning treatment. The results show significant improvement in the tribological properties of triboconditioned components. The improvement is attributed to the formation of WS2 tribofilms at the component surface and a modified surface roughness profile with reduced core roughness (Rk) and peak height (Rpk). Elemental composition of the tribofilms generated by the triboconditioning process has been studied by X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy the surface profile of the treated components has been studied using vertical scanning interferometry and the internal structure of the tribofilms has been studied with focused ion beam-transmission electron microscope technique. © 2013 John Wiley & Sons, Ltd. Source

Da Silva Trindade W.R.,MAHLE Metal Leve SA
SAE Technical Papers

During the development of a air intake manifold simulation is necessary to verify the component characteristics in terms of flow considering runner in-balance as focus. Results can also present exhaust gases recirculation (EGR) distribution affecting each of the different runners in order to verify if those recirculated exhaust gases were been equally distributed among all the runner outlets or, at least, presenting a percentual difference of EGR concentration in each runner inside a defined tolerance range. Aiming these results some calculation techniques were used as follow: 1D modeling as well as 3D modeling was used1D model was built using GT-Power and 3D modeling was done using computational fluid dynamics based on ANSYS FLUENT. First results were obtained from 1D model and 3D model running apart. 1D modeling was focused in performance issues (torque and power); 3D modeling was a steady state, multiphase calculation, looking for qualitative results like density and mixing of gases, to verify the flow distribution inside the intake manifold. Pressure loss results were verified but not as main result of this work. A baseline EGR mixer was also tested looking for its efficiency and a new EGR mixer design proposal could took place at this moment, if it was necessary. The distribution of EGR for the runners was obtained from a 1D-3D coupling, it means: 1D model and 3D model were run simultaneously,1D flow results at manifold inlet and EGR valve outlet were passed to CFD model and used as boundary conditions and3D flow results at runners were so passed to 1D model and used as boundary conditions to continue the flow calculation. That sequence was run until convergence were obtained considering at least 10 coupled cycles. Copyright © 2010 SAE International. Source

Mahle Metal Leve S.A. and Mahle GmbH | Date: 2011-06-01

An oil control ring for internal combustion engines, formed by a ferrous body having two external contact surfaces where each surface contains first and second extremity edges, two tilted faces where each tilted face starts from the respective second edge, a peripheral transversal section directed at the cylinder wall and an internal circular section directed at the side of the piston, where the projections of contact are directed, so that the respective tilted faces are turned facing the other, symmetrically, in a preferred concretization. The ring allows the maintenance of appropriate levels of contact pressure, even under reduced expanding loadings due to the use of profile that brings reduced contact of the ring with the cylinder interface. Additionally, it brings better dynamic stability and consequent distribution of the contact pressure of the set. It also makes it possible to apply superficial hardening treatments on oil rings with reduced contact surface.

Mahle Metal Leve S.A. | Date: 2011-12-22

The fuel filter comprises: a housing (

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