• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.5
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• pp.326-332
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• 2010

Critical response of seawater pump impeller shaft structure to various exciting loads is a fundamental factor in re-designing of the structure after its functional failure. In this paper, a typical case of the shaft structure's failure is investigated for re-designing purposes. Failure causes of interest are excessive bending moment, fatigue loads and dynamic resonance due to relevant motor rotation and unbalancing of the rotation loads. Static analyses of shaft structure under the conditions of concerned loads are carried out, followed by a dynamic investigation of the effects of resonance between the shaft and the motor on the structure. The relevant structural analyses are carried out using the Finite Element Methods combined with ANSYS code. Based on these, the primary cause for the shaft's structural failure is obtained. It is found that the change of the bending stiffness of the shaft is the primary concern in the re-designing process. A guideline for the re-design process of the seawater pump shaft structure is established, and a re-design scheme of the structure is proposed.

• Korean Chemical Engineering Research
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• v.59 no.4
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• pp.542-547
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• 2021

Glass lined impellers are corrosion resistant to most chemicals, including strong acids, and also have a smooth, non-stick surface, easy to clean and free from impurities in the process. Glass lined home base impeller is a multi-purpose impeller designed to stir a wide viscosity range of liquids from low viscosity fluids to high viscosity fluids, among others, cell culture, yeast culture, and beer fermentation pots, especially used for air-water system breathable stirring. The glass lining for HB impellers, which are simple in structure and competitive in performance, is essential to have upper and lower division in order to make the joint area between the impeller and shaft as small as possible. The upper and lower division of the impeller hardly affects the mixing performance, but the aeration performance. In this study, in order to optimize the shape of the Glass Lining HB impeller, a study was conducted on the effect of the angle between the upper and lower impellers, the clearance between the impellers, and the number of baffles on the aeration power. The optimal shape and baffle plate conditions for the Glass lined HB impeller were derived through the study results that the angle and the clearance between the upper and lower impellers decreased the ration of the power consumption with aeration P_g and that without aeration P₀, P_g/P₀.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.2
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• pp.56-62
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• 2017

In this research, reverse engineering was applied to the product manufactured by "Vanzetti" from Italy to develop a localized cryogenic submerged pump used in small-scale LNG liquefaction plants. The results of modal analysis of the impeller and shaft confirmed that the resonance frequency of the impeller and shaft played an important role in the rotor. Modal analysis of the rotor confirmed that the forcing frequency had no influence on the resonance phenomenon.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.3
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• pp.246-252
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• 2014

This study is on the development of 150PS inboard type of compact water jet propulsion system. The water jet is composed of intake, impeller, diffuser, reverse bucket and main shaft. Components of water jet have been manufactured through precision processing after sand casting. Development of water jet propelled engine has been finally completed by processes which are design, production and inspection on each component. The water jet performance characteristics show that 0.29 m3/s of maximum flow rate and 37 m/s of flow velocity have been secured in the ground test pool. Field test was performed by 21ft test ship that water jet propulsion equipment developed in this study was installed. As a result, the weight of hull, engine and other parts of the ship has been almost 1.2 ton and 45 km/h of maximum sailing speed has been recorded with 3700 rpm of engine in the domestic coast test.