• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.737-738
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• 2012

• Tribology and Lubricants
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• v.31 no.2
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• pp.35-41
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• 2015

A water-pump located in the cooling area of a car circulates cooling water. A particular bearing element, known as a water-pump bearing, installed in the rotating part carries the entire load. The failure of this water-pump bearing has a direct impact on the failure of the automobile engine, and so securing its reliability is crucial. Several researchers have examined the design principles of the water-pump bearing, but there are no reports on the life characteristic of the bearing yet. Herein, we report the construction of test equipment to reproduce the spalling of the roller contact, which is the main failure mode of the chosen water-pump bearing. We chose the radial load as an accelerated stress factor and validated the failure mode by monitoring the surface defects. We conducted the accelerated life test after determining the accelerated stress level through a combination of finite element analysis and a preliminary test. In the life tests, we used an accelerometer to perform failure diagnosis. In the last stage of this study, we present a statistical reliability analysis. Thus, we fully estimated the shape parameter of the water-pump bearing, accelerating level on the load , and the lifetime (MTTF and B₁₀ life) under real use conditions, and finally proposed an interval estimation value considering the uncertainty of the estimated value.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.3
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• pp.164-169
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• 2006

A systematic methodology has been proposed to establish a reliable design of water pump system. A simplified steady-state dynamic model of water pump system has been developed to study the response of water pump system to the dynamic load mainly due to the run-out and unbalance. Design modifications are needed to strengthen the structural integrity of existing designs. Increasing the natural frequency of system is pursued to prevent a resonance from occurring in the engine excitation range. A computational reliability methodology combined with finite element analysis is used to identify the most significant factor affecting the system performance. This method considered influence of design control parameters for the performance of design. By including control factors to the system model in a systematic way, more reliable design is expected.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.2
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• pp.186-193
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• 2014

This paper presents characteristic analysis of underwater bearing for canned type electric water pump. Characteristic analysis of underwater bearing was performed using self-developed performance tester, which capable of torque change, noise change, motor speed change and abrasion loss test with respect to temperature change of underwater bearing. The performance tester can be monitored in real time by designing the control unit using the Labview program. The performance experiment was performed through comparison of the silicon carbide (SIC) and the carbon bearing. From the experiment results, performance of SIC bearing was better than carbon bearing at the abrasion and temperature experiment.