OPERATIONAL EVALUATION OF PISTON-RINGS-CYLINDER LINER ASSEMBLY WEAR IN HIGH POWER MARINE DIESEL ENGINES

Tribologia ◽  
2018 ◽  
Vol 271 (1) ◽  
pp. 5-15
Author(s):  
Adam ADAMKIEWICZ ◽  
Jan DRZEWIENIECKI

This paper presents an operational evaluation of piston-piston rings-cylinder liner (PRC) assembly wear in marine diesel engines of high power. It is based on visual inspection through cylinder liner scavenge ports. Clearance measurements of piston rings in piston grooves and piston ring gap measurements were used to evaluate the extent of wear of the PRC assembly. Moreover, it is shown that piston ring gap measurements can be used as a reference parameter in wear trend analysis to predict the length of time periods between overhauls (TBO). Furthermore, it has been shown that controlling the wear of chromium (protective) layers of piston ring working surfaces by measuring their thickness with induction and eddy current methods is highly useful. They were accepted as a source of information on PRC lubrication correctness and as a symptom of its technical condition. Factors indicating the necessity of an overhaul and introducing operational methods of improving working conditions between the tribological pair – liner and piston rings have been determined.

1994 ◽  
Vol 29 (3) ◽  
pp. 261-267
Author(s):  
Keijiro Tayama ◽  
Kazuhiko Maekawa ◽  
Keizo Gotoh ◽  
Noriyasu Inenaga

2014 ◽  
Vol 620 ◽  
pp. 278-284 ◽  
Author(s):  
Salaheldin A. Mohamad ◽  
Qun Zheng ◽  
Xi Qun Lu

Piston ring lubrication in some types of low-speed 2-stroke marine diesel engines is completely different from those in medium-or high-speed diesel engines since the inner surface of cylinder liners are textured with circular grooves in macro-scale and honing texture in micro-scale. In this paper, a numerical model has been developed to study the potential of use of cylinder bore surface texturing, in the form of circumferential oil grooves with different dimensions and densities, and their efficiency to improve the tribological properties of piston ring-cylinder liner tribo-system. The average Reynolds equation has been employed in the area of micro-scale texture and the effect of macro-scale grooves has been incorporated to improve the currently lubrication model. The results showed that the cylinder liner oil grooves can efficiently be used to maintain hydrodynamic effect. It is also shown that optimum surface texturing may substantially reduce the friction losses between piston ring and cylinder liner.


Friction ◽  
2021 ◽  
Author(s):  
Chenwei Miao ◽  
Zhiwei Guo ◽  
Chengqing Yuan

AbstractThe running-in of cylinder liner-piston rings (CLPRs) is the most important process that must be performed before a marine diesel engine can be operated. The quality of running-in directly affects the reliability of a CLPR. The surface texture of a CLPR has been proven to significantly affect its lubrication performance. In this study, the tribological behavior of a CLPR during running-in is investigated. Three types of surface textures are generated on the CLPR via laser processing: dimple texture on piston rings, groove texture on cylinder liners, and co-texture on both sides. Subsequently, a series of tests are performed on a slice tester. A load of 300 N (1.64 MPa) is applied, and two speeds (50 and 100 rpm) are adopted. The CLPR running-in quality is characterized based on three parameters, i.e., the friction coefficient, contact resistance, and wear topography. Experimental results show that, compared with a non-textured surface, the three types of surface textures mentioned above improved the friction performance during running-in. The lubricant supply capacity of the dimple texture on the piston ring, as a mobile oil reservoir, is stronger than that of the groove texture on the cylinder liner serving as a static oil reservoir. By contrast, the wear resistance of the dimple texture, as a movable debris trap on the piston ring, is weaker than that of the groove texture on the cylinder liner, which serves as a static debris trap. It is demonstrated that the co-texture combines the advantages of dimples and groove textures. Compared with non-textured surfaces, the friction coefficient decreased the most at 100 rpm (44.5%), and the contact resistance improved the most at 50 rpm (352.9%). The coupling effect provides the surface with improved running-in quality by optimizing the tribological performance, particularly at the dead center. This study provides guidance for the tribological design and manufacturing of CLPR in marine diesel engines.


2021 ◽  
pp. 56-60
Author(s):  
Konstantin Valentinovich Safonov ◽  
◽  
Valentin Vladimirovich Safonov ◽  
Valeriy Vasilyevich Ostrikov ◽  
Shamil Magomedovich Igitov ◽  
...  

At operation of KAMAZ motor vehicles a significant number of failures (40–55 %) are attributed to engine, among the elements of which a cylinder and piston group often breaks down. One of the effective ways to increase the wear resistance of rubbing parts of the engine is the modification of lubricating medium by special abovebase additives, among which nanoscale powders are widely distributed. The paper is devoted to investigation of influence of the «Klaster-V» nanoadditive that is developed for motor oil in order to increase life of a «piston ring — cylinder liner» interface of KAMAZ motor vehicles. As a parameter of technical condition of the interface the authors have assumed a value of a gap between a piston ring and a cylinder liner of an internal combustion engine. Results of operational tests show that the forecasting residual life of the «piston ring — cylinder liner» interface of diesel engines tested on oil with «Klaster-V» additive have increased by 2.15 times on average in comparison with the residual life of diesel engines operated on Lukoil 15W40 motor oil.


2018 ◽  
Vol 70 (4) ◽  
pp. 687-699 ◽  
Author(s):  
Thomas Wopelka ◽  
Ulrike Cihak-Bayr ◽  
Claudia Lenauer ◽  
Ferenc Ditrói ◽  
Sándor Takács ◽  
...  

Purpose This paper aims to investigate the wear behaviour of different materials for cylinder liners and piston rings in a linear reciprocating tribometer with special focus on the wear of the cylinder liner in the boundary lubrication regime. Design/methodology/approach Conventional nitrided steel, as well as diamond-like carbon and chromium nitride-coated piston rings, were tested against cast iron, AlSi and Fe-coated AlSi cylinder liners. The experiments were carried out with samples produced from original engine parts to have the original surface topography available. Radioactive tracer isotopes were used to measure cylinder liner wear continuously, enabling separation of running-in and steady-state wear. Findings A ranking of the material pairings with respect to wear behaviour of the cylinder liner was found. Post-test inspection of the cylinder samples by scanning electron microscopy (SEM) revealed differences in the wear mechanisms for the different material combinations. The results show that the running-in and steady-state wear of the liners can be reduced by choosing the appropriate material for the piston ring. Originality/value The use of original engine parts in a closely controlled tribometer environment under realistic loading conditions, in conjunction with continuous and highly sensitive wear measurement methods and a detailed SEM analysis of the wear mechanisms, forms an intermediate step between engine testing and laboratory environment testing.


2020 ◽  
Vol 143 (4) ◽  
Author(s):  
Avinash Kumar Agarwal ◽  
Deepak Agarwal

Abstract This study investigated the use of biodiesel (B100) and baseline mineral diesel in two identical unmodified vehicles to realistically assess different aspects of biodiesel’s compatibility and durability issues with modern common rail direct injection (CRDI) engine-powered vehicles. Two identical vehicles were operated for 30,000 km under identical operating conditions during a field-trial using biodiesel (B100) and mineral diesel. Exhaustive experimental results from this series of tests are divided into four sections, and this is the third paper of this series of four papers, which covers comparative feasibility and wear analyses, underlining the effect of long-term use of biodiesel on wear of cylinder liner and piston rings compared to baseline mineral diesel-fueled vehicle. Surface microstructures at three locations of the cylinder liner were evaluated using scanning electron microscopy (SEM). Wear was found to be relatively lower at all locations of liners from biodiesel-fueled vehicle compared to diesel-fueled vehicle. Surface roughness of cylinder liners measured at different locations showed that it reduced by ∼30–40% at top dead center (TDC), ∼10–20% at mid-stroke, and ∼20–30% at bottom dead center (BDC) for both vehicles, showing higher wear close to TDC compared to mid-stroke and BDC locations. Loss of piston-ring weight was significantly lower for biodiesel-fueled vehicle. Engine tear-down observations and carbon deposits on various engine components were recorded after the conclusion of the field trials. During these field-trials, engine durability-related issues such as fuel-filter plugging, injector coking, piston-ring sticking, carbon deposits in the combustion chamber, and contamination of lubricating oils were found to be relatively lower in biodiesel-fueled vehicle. Overall, no noticeable durability issues were recorded because of the use of biodiesel in CRDI engine-powered vehicle.


Author(s):  
Sylvester Abanteriba

The compression and oil rings of the piston engine play a very important role in the performance and reliability of the piston engine. The rings are required to accomplish three main distinct tasks: 1. Sealing the combustion chamber gas from the crankcase to eliminate blow-by phenomenon, which constitutes the flow of some of the contents of the combustion chamber into the crankcase. 2. Proper distribution of the lubricating oil film over the piston skirt and cylinder liner. 3. Transfer of heat from piston to cylinder liner. Unfortunately the piston ring pack contributes to the highest proportion of the frictional losses in the engine and is more prone to high wear rates. In the engine, the compression rings are designed to provide effective sealing of the crankcase against the gases from the combustion chamber. The oil-rings provide an effective means of distributing the lubricating oil over the cylinder liner while keeping it from flowing into the combustion chamber. The ability of the compression rings to serve as a gas seal depends on their axial position within the groove. The ring needs to be in contact with the lower flank in order to provide the requisite sealing effect. Once the ring lifts itself from the lower flank its ability to act as an effective seal is compromised. The axial motion of the piston rings during the operation of the engine engenders blow-by and therefore has deteriorating effect on the engine performance. Not much work has, hereto, been done to study the impact of altitude on the movement of the piston rings and hence the blow-by phenomenon. This papers presents a simulation model to investigate this effect.


2019 ◽  
Vol 72 (5) ◽  
pp. 581-588
Author(s):  
Jiazhi Miao ◽  
Yongqing Li ◽  
Xiang Rao ◽  
Libao Zhu ◽  
Zhiwei Guo ◽  
...  

Purpose The emission from marine engines has a crucial effect on energy economy and environment pollution. One of the effective emission reduction schemes is to minimize the friction loss of main friction pairs such as cylinder liner-piston ring (CLPR). Micro-groove textures were designed to accomplish this aim. Design/methodology/approach The authors experimentally investigated the effects of micro-groove textures at different cylinder liner positions. The micro-groove texture was fabricated on samples by chemical etching and cut from the real CLPR pair. Sliding contact tests were conducted by a reciprocation test apparatus. Findings The average friction coefficient of grooves at 30° inclination were reduced up to 58.22% and produced better tribological behavior at most conditions. The operating condition was the critical factor that determined the optimum texture pattern. The surface morphology indicated that textures could produce smoother surfaces and less scratches as compared with the untextured surface. Originality/value Inclined grooves and V-grooves were designed and applied to real CLPR pairs. The knowledge obtained in this study will lead to practical basis for tribological design and manufacturing of CLPR pair in marine diesel engines.


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