실린더 라이너 오일그루브 가공 로봇 시스템 개발

노태양(Tae-yang Noh),이윤식(Yun-sik Lee),정창욱(Chang-wook Jung),이지형(Ji-hyung Lee),오용출(Yong-chul Oh) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.11

An engine for marine propulsion and power generation consists of several cylinder liner-piston sets. And the oil groove is on the cylinder liner inside wall for the lubrication between a piston and cylinder. The machining process of oil groove has been carried by manual work so far, because of the diversity of the shape. Recently, we developed an automatic grinding robot system for oil groove machining of engine cylinder liners. It can covers various types of oil grooves and adjust its position by itself. The grinding robot system consists of a robot, a machining tool head, sensors and a control system. The robot automatically recognizes the cylinder liner's inside configuration by using a laser displacement sensor and a vision sensor after the cylinder liner is placed on a set-up equipment.

승용디젤엔진용 고내구 주철 실린더 라이너 개발

박훈영(Park, Hun Young),박성환(Park, Seong hwan),고영상(Ko, Young Sang) 한국자동차공학회 2018 한국자동차공학회 학술대회 및 전시회 Vol.2018 No.11

In order to achieve the needs of continuous improvement of fuel efficiency of the engine, the development of the passenger diesel engine is progressing in the direction of increasing the combustion pressure for the lightening of the engine and the combustion efficiency. Especially, The cylinder block constituting the combustion chamber is a core part having the largest weight in the engine. Therefore, Aluminum block with cast iron cylinder liners is developing to reduce the weight of integrated cast iron structural blocks. However, cylinder liners currently used in gasoline engine aluminum block have gray cast iron with a tensile strength of 250MPa, which limits the durability of passenger diesel engines with combustion pressures up to 70% higher than gasoline engines. In this study, high strength cast iron added Mo, Cu, Ni has been developed, and its tensile strength has been increased by 16% and the bonding strength with Al cylinder block by 19% compared with the conventional cylinder liner. Also hardening mechanism and durability, workability of developed high strength cylinder liner were investigated.

실린더 라이너 오일그루브 가공 로봇 시스템 개발

노태양(Tae-yang Noh),이윤식(Yun-sik Lee),정창욱(Chang-wook Jung),오용출(Yong-chul Oh) 대한기계학회 2009 大韓機械學會論文集A Vol.33 No.6

An engine for marine propulsion and power generation consists of several cylinder liner-piston sets. And the oil groove is on the cylinder liner inside wall for the lubrication between a piston and cylinder. The machining process of oil groove has been carried by manual work so far, because of the diversity of the shape. Recently, we developed an automatic grinding robot system for oil groove machining of engine cylinder liners. It can covers various types of oil grooves and adjust its position by itself. The grinding robot system consists of a robot, a machining tool head, sensors and a control system. The robot automatically recognizes the cylinder liner's inside configuration by using a laser displacement sensor and a vision sensor after the cylinder liner is placed on a set-up equipment.

호닝 가공을 이용한 디젤엔진 실린더 라이너 보어의 가공오차 개선에 관한 연구

이기삼,손휘준,김석,조영태 한국기계가공학회 2023 한국기계가공학회지 Vol.22 No.10

Cylinder liners play a pivotal role in internal combustion engines and directly influence the engine performance. Honing is a crucial process for enhancing the shape accuracy and surface quality of cylindrical liners during dieselengine manufacturing. However, the processing conditions and inconsistent particle dislodgment from the whetstonemake it challenging to maintain the quality during honing. This study focuses on optimizing the honing process torectify shape errors such as roundness and parallelism in a cylinder liner. The study selected the optimalcompensation conditions for shape tolerance by utilizing variables such as the honing stone extension and spindlespeed. In addition, it compares the outcomes through methods such as feed stop time and selective part processing,thus pinpointing the factors primarily responsible for minimizing shape errors. The processing conditions werefine-tuned to address the deviations in the surface roughness along the inner wall of the cylinder. Particledislodgment was controlled by altering the direction of spindle rotation, thus facilitating a smoother autogenousaction. Through experimentation, the shape errors and surface roughness issues arising from the cylinder liner honingprocess were rectified, culminating in a comprehensive processing strategy to consistently uphold high-qualitystandards. This study facilitates the establishment of precise processing conditions for honing, validation of productreliability, and optimization of the honing process.

Evaluation of Characteristics of CBN Honing Stone for Cylinder Liner Honing of Marine Diesel Engine

Jeong, Jae-Hyun,Kim, Jong-Sun,Lee, Yeon-Chang,Lee, Sung-Yul,Moon, Kyung-Man,Kim, Yun-Hae Korean Society of Ocean Engineers 2012 International journal of ocean system engineering Vol.2 No.4

The cylinder liner of a low speed engine is one of the most important parts of the marine diesel engines used in merchant ships. However, a sufficient degree of precision in the manufacturing method for these cylinder liners has never existed. Conventional honing stones have always been used for machining large marine cylinder liners. Therefore, it is necessary to develop a honing process that optimizes the honing characteristics. In this study, a CBN honing stone was manufactured to improve the honing performance for a cylinder liner and shorten the processing time, and machining experiments on a practical cylinder liner were carried out. Then, a comparison was made between the CBN honing and honing with a conventional GC stone using parameters such as the honing time, machining quantity, and honing cost. As a result, for a #60 CBN stone, the machining amount was significantly improved compared to the conventional one by about $1.1{\mu}m$/min, and in respect to the machining cost, a reduction of about 57% was achieved. However, an improvement in the process with a #800 CBN stone could not be expected because it did not show a significant difference compared to the case of the existing stone. From the above results, if the liner were honed using a CBN honing stone, the rough machining and intermediate processing during an early stage of the honing process were excellent compared to the conventional one. However, we could not find a significant difference in the case of finish honing.

Tribological properties of twin wire arc spray coated aluminum cylinder liner

Kim, J.K.,Xavier, F.A.,Kim, D.E. Scientific and Technical Press ; Elsevier Science 2015 Materials & Design Vol.84 No.-

The effects of honing process on the friction and wear behaviors of Twin Wire Arc Spray (TWAS) coated aluminum cylinder liners were investigated using a pin-on-reciprocating type of a tribotester. Two types of coated cylinder liners were prepared for the tests: Type I - smooth honing (SH) with ~40<SUP>o</SUP> honing angle, and Type II - helical structure honing (HSH) with ~140<SUP>o</SUP> honing angle. The aluminum cylinder liners were coated with an Fe0.8C wire by the TWAS process. In un-lubricated condition, Type II specimen showed lower coefficient of friction (COF) compared to Type I specimen. This result was due to the fact that the groove of Type II was sufficiently large to trap the wear particles that may otherwise contribute to three body abrasive wear. In lubricated condition, Type I showed lower COF due to its lower roughness in comparison to Type II. The experimental results indicate that TWAS process can be effectively utilized for engine applications in conjunction with optimum honing process for the cylinder liner.

ADAPTABILITY OF LASER TEXTURED LINER TO THE EFFECTS OF METHANOL DILUTING OIL ON TRIBOLOGICAL PROPERTIES

Jia He Kun,Xu Bo,Yin Bifeng,Jiang Yuhao,Hu Nanrong 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.2

With the increase of methanol diluting lubrication oil, the dynamic viscosity of the mixture presents a downward trend, the total acid number grows while the total base number declines, and the corrosion degree of copper strip upgrades, which indicates that methanol dilution has negative effects on lubrication and anti-corrosion performance of oil. According to ball-on-plate friction test results, the friction coefficient and surface wear of this pair increase in turn with the rising methanol dilution rate, which tends to deteriorate the tribological performance of key friction pairs in methanol engine. After laser surface texturing cylinder liner, the friction coefficient of ring/liner pair is reduced, and the anti-friction effect is enhanced with the rising methanol dilution rate, because the oil storage capacity of textured micro-dimples on liner surface can improve the lubrication of ring/liner pair and reduce asperity contact. Moreover, the micro-dimples can store debris generated in the reciprocating friction process of this pair, so as to alleviate surface wear caused by abrasive wear, and improve the wear resistance of cylinder liner. Therefore, laser texturing cylinder liner can compensate the deterioration of friction and wear performance of ring/liner pair caused by methanol diluting oil with good lubrication adaptability.

피스톤 링과 원형 미세공이 가공된 실린더 라이너의 유체윤활해석

손상익(Sang-Ik Son),김성기(Sung-Gi Kim),김경웅(Kyung-Woong Kim) 한국트라이볼로지학회 2009 한국트라이볼로지학회 학술대회 Vol.2009 No.11

Friction loss occurring between a piston ring and a cylinder liner is most of thai in an internal combustion engine. Recently, the surface texturing technique to generate micro-dimples on a cylinder liner has been used in order to decrease friction loss and increase the efficiency of an engine. In this study, the effect of micro-dimples on the hydrodynamic lubrication characteristics between a piston ring and a micro-dimpled cylinder liner is analyzed numerically. Elrod's cavitation algorithm which implements JFO oil rupture / reformation boundary condition is adopted in order to predict the cavitation region and calculate the pressure distribution between a piston ring and a micro-dimpled cylinder liner. The depth, radius and gap of micro-dimples are considered as design parameters, and the analysis is carried out by varying those. The result shows that micro-dimples can make the minimum film thickness during the full engine cycle increase and friction loss decrease in comparison with a non-textured cylinder liner.

A Study on Effect of Recirculated Exhaust Gas upon Wear of Cylinder Liner and Piston in Diesel Engines

배명완,Bae, Myung-Whan,Tsuchiya, Kazuo 대한기계학회 2001 KSME International Journal Vol.15 No.11

The effects of recirculated exhaust gas on the wear of cylinder liner and piston were experimentally investigated by a two-cylinder, four cycle, indirect injection diesel engine operating at 75% lo ad and 1600 rpm. For the purpose of comparison between the wear rates of the two cylinders with and without EGR, the recirculated exhaust gas was sucked into one of two cylinders after the soot in exhaust emissions was removed by an intentionally designed cylinder-type scrubber equipped with 6 water injectors(A water injector has 144 nozzles of 1.0 mm diameter), while only the fresh air was inhaled into the other cylinder. These experiments were carried out with the fuel injection timing fixed at 15.3$^{\circ}$ BTDC. It was found that the mean wear rate of cylinder liner with EGR was greater in the measurement positions of the second half than those of the first half, that the mean wear rate without EGR was almost uniform regardless of measurement positions, and that the wear rate of piston skirt with EGR increased a little bit, but the piston head diameter increased, rather than decreased, owing to soot adhesion and erosion wear, and especially larger with EGR.

3D EHD LUBRICATION AND WEAR FOR PISTON RING-CYLINDER LINER ON DIESEL ENGINES

Y. K. JIANG,J. P. ZHANG,G. HONG,L. P. WAN,X. LIU 한국자동차공학회 2015 International journal of automotive technology Vol.16 No.1

The three-dimensional EHD lubrication and wear loss of piston ring-cylinder liner components for five rings in the firing diesel engine was studied by using VC++ programs. The gas blowby, variable density and viscosity of lubricant, the surface roughness, friction heat flux and the normal elastic deformation are all considered in the EHD lubrication analysis algorithm. Meanwhile, the wear loss of the cylinder liner was also calculated when the diesel was started under cold starting condition in which the wearing was more serious than that in warm starting condition. The simulated results were compared with the wear measurement of the cylinder liner, and they matched well. It was found that the hydrodynamic friction force was larger than the asperity friction force, and the wear distribution of the barrel piston ring was very different from that of the rectangular piston ring. The distribution trend of the nominal oil film thickness was similar to the normal elastic deformation, but opposite to the wear loss of the piston rings. The wear loss caused by the first piston ring was the biggest and played a dominant role in the wear loss of cylinder liner. The greatest wear loss of the cylinder liner occurs at the time near top dead centre.