• Tribology and Lubricants
• /
• v.20 no.4
• /
• pp.204-208
• /
• 2004

This paper presents the oil leakage characteristics of the valve stem system in gasoline engines. For the oil leakage investigation, four study models have been prepared as functions of used poppet valve and used valve stem seal, used poppet valve and unused valve stem seal, unused poppet valve and used valve stem seal, and unused poppet valve and unused valve stem seal. With four models, the experimental study on the oil leakage has been investigated for the oil temperature, intake pressure, and camshaft speed. The experimental results show that the sealing performance of the valve stem seal plays an important role on the leakage of the valve stem system. And the appropriate replacement of a stem seal with used poppet valve shows good sealing performance in oil leakage in compared with a new valve system.

• Tribology and Lubricants
• /
• v.14 no.2
• /
• pp.21-25
• /
• 1998

This paper presents the experimental results of the friction characteristics of double liptype oil seals which show an improvement in sealing performance over single lip-type oil seals. The major differences between two oil seals are the number of contact lip, and seal materials; Nitrile Butadine Rubber(NBR) and urethane rubber. The measured results show that the friction torques of double lip seals show 12-17% increases compared with those of single lip-type seals. But the sealing performance and service life of double lip oil seals have been increased and stabilized due to an optimized design of the seal lip and material properties.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1998.04a
• /
• pp.307-313
• /
• 1998

This paper presents the experimental results of the friction characteristics of double lip-type oil seals which show an improvement in sealing performance over single lip-type oil seals. The major differences between two oil seals are the number of contact lip and seal materials; Nitrile Butadine Rubber(NBR) and urethane rubber. The measured results show that the friction torque of double lip seals shows 12-17% increases compared with those of single lip-type seals. But the sealing performance and service life of double tip oil seals have been increased and stabilized due to an optimized design of the seal lip and material properties.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.9 no.3
• /
• pp.83-88
• /
• 2010

This study aimed to enhance the durability by distributing the stress concentration at the contact and increasing the mechanical characteristics, as well as by changing the surface shape for LIP in the low-pressure seal among oil seals installed to the power steering of automotive. Accordingly, results were derived from comparisons and reviews with oil seals under the existing mass production by carrying out the performance tests after designs and productions are done with the addition of embo shapes on the surface of LIP in the low-pressure seal. As a result of this study, it has been identified that the durability of oil seals with the addition of embo shapes was enhanced with higher radial force and less variation in the internal diameter for the LIP. In addition, it was seen that the sealing ability for those oil seals is superior to the existing oil seals as their rotational torque values are less than those of the existing oil seals.

• Journal of the Korean Society for Railway
• /
• v.9 no.6 s.37
• /
• pp.630-634
• /
• 2006

Rail car axles are very important parts for safety of passengers and structural integrity of vehicles. The axles are supported by bearings. To seal grease lubricating the bearings of freight cars, an oil seal has been developed. The developed oil seal is composed of an inner plate, an outer plate and a seal rubber. The friction between axle and housing with the developed oil seal is very low. The seals are designed for a minimum life expectancy of 800,000 kilometers service. In this study, an accelerated durability tests according to AAR Specification M-934-82 were carried out. In addition, various performance tests according to KS B 2804 were conducted.

• Elastomers and Composites
• /
• v.53 no.1
• /
• pp.13-18
• /
• 2018

A face seal comprising a metal ring and acrylonitrile butadiene rubber (NBR) was installed in the driving part and suspension unit. The seal serves as a bearing and simultaneously prevents entry of foreign matter from external environment as well as internal oil leakage. Subsequently, the rubber-rod ring generates axial pressure owing to rubber elasticity (hardness), performs static sealing function between housing details and outer diameter of seal, and transmits rotational torque to the rotating support ring. In order to improve the durability of NBR, which performs the above tasks, and to effectively use it in tracked-vehicle applications at extreme temperatures, this study reports a mixing design approach to enhance cold and oil resistances of NBR.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.18 no.1
• /
• pp.85-93
• /
• 2019

Oil seals are most essential parts in mechanical lubrication system to maintain the close gaps between stationary and high rotating components, and to help prevent oil leakages. Oil seals also can prevent harmful contaminants entering from outside to machinery, especially in severe environments. Therefore, the oil seals have an important performance in the machinery components. The performance of the oil seals are influenced by the design variables such as amount of interference gap between the main lip and shaft, the angle of main lip at air and oil sides and the distance between the garter spring and main lip. In the present study, a finite element analysis was performed to evaluate the oil seal performance with the considerations of number of oil seal dust lips and angle of the lip at oil side with the different design variables. As a result from the FEM analysis, the stress and contact pressure distributions was derived, based on this, performance of the sealing and durability were determined.

• Journal of the Korean Magnetics Society
• /
• v.4 no.4
• /
• pp.326-334
• /
• 1994

This paper describes the fabrication of the hydrophilic magnetic fluid with high viscosity and its application to oil seal apparatus used with the Nd-permanent magnet. The results are as follows. 1) The ultrafine magnetite particles under the size of $100\;{\AA}$ are first coated by the oleic acid ion and again adsorbed by the hydrophilic D. B. S. ion, and there by hydrophilic magnetic fluid with high viscosity could be made by dispersing them into the ethylene glycol. 2) In development of the oil seal apparatus using magnetic fluid and Nd-permanent magnet, the viscosity and magnetic susceptibility show high when the $Fe_{3}O_{4}$ content is over 50%(g/cc) in the fluid, so that such properties could improve highly the capability of oil seal. 3) The maximum of the resisting pressure of the oil seal using the ethylene glycol base magnetic fluid and the Nd-permanent magnet, is about $50\;g/\textrm{cm}^2$, under the condition of this experiment. Therefore the oil seal may not be suitable for the ship engine and the driving part of the automobile, and thus it needs a lot further complementary reserch. However, it is quite favourable for such an oil seal apparatus as speed reducer under the condition of atmospheric pressure.

• Proceedings of the Korean Reliability Society Conference
• /
• 2006.05a
• /
• pp.40-47
• /
• 2006

Rail car axles are very important parts for safety of passengers and structural integrity of vehicles. The axles are supported by bearings. To seal grease lubricating the bearings of freight cars, a non-contact oil seal has been developed. The developed oil seal is composed of inner plate, outer plate and seal rubber. The friction between axle and housing with the developed oil seal is very low. The seals are designed for a minimum life expectancy of 800,000 kilometers service. In this study, an accelerated durability tests according to AAR Specification M-934-82 were carried out. Developed products satisfy the AAR Specifications.

• KSTLE International Journal
• /
• v.1 no.1
• /
• pp.59-62
• /
• 2000

This paper deals with an experimental study on the dynamic response of an elastomeric oil seal when the interferences between shaft and lip as well as the dynamic eccentricities are present. The dynamic response of seal lip in oil seals was observed with the aid of an image processing apparatus. The temperature of the seal lip edge, friction torque and the dynamic sealing gap between shaft and lip are measured at different conditions of the initial interference and the shaft eccentricity, The data were simultaneously measured under dynamic conditions. Experimental results show that, as the shaft speed is increased, S/e$_{d}$ has nearly reached a constant asymptotic value fur a certain range of shaft speeds. The results indicate that the gap separation between shaft and lip is provided due to the shaft eccentricity because the seal lip cannot follow quickly the radial displacements with increasing shaft speed.d.