• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.5
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• pp.553-558
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• 2011

This study have goal with conceptual design for offshore structures of high pressure drop control valve for localization valve for development accomplished with flow analysis based on provision of ANSI B16.34, ANSI B16.10, ANSI B16.25. In order to localize the Offshore structures high pressure drop control valve. This study is numerical analysis for zambil offshore project of high pressure drop control valve. The solver which ANSYS workbench used for offshore structures analysis. The working fluids assumed the glycerin(C3H8O3). The structural analysis used ANSYS which is a commercial code. Stress analysis result of internal pressure in valve showed lower than yield strength. This is expect to need more detail design and verification for stem and disk structure. In this study a multi-disk of high pressure drop control valve is designed and manufactured. Then, the flow rate and high pressure dorp of fluids flowing in the high pressure drop control valve is CAE. So, this system can be easily substituted for the existing zambil offshore project system. Finally, safety estimation for trim design of high pressure drop control valve for offshore structures.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.5
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• pp.767-773
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• 2013

A high-pressure, high-pressure drop control valve, which transforms the power transfer of a system by reducing the inlet pressure of 345bartothe outlet pressure of 112bar, is a fundamental component in an offshore plant process. With the increasingly growing market share of the maritime industry, this valve has been expected to be a high-value-added product. This study not only analyzes the relation between pressure drop and fluid velocity in a trim by using fluid analysis, but also examines the possibility of cavitation in a valve in addition to the plot for the extension of lifespan. Based on the analysis results, the design and production method of the valve are established, and accordingly, performance evaluation is carried out. It is demonstrated that the pressure drop from 345bar to 112bar is more feasible in the presence of the trim, which can induce a continuous and diminutive pressure drop in order to prevent cavitation in a high-pressure drop control valve. Furthermore, despite the fluid velocity near a seatring being found to be over 30m/s, the lifespan of the valve is determined to be adequate considering the operation condition of a prototype valve of 80%.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.5
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• pp.42-49
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• 2015

In this study, the multi-disk of a high-pressure drop control valve is designed and manufactured. Then, the flow rate and high-pressure drop of fluids flowing in the high-pressure drop control valve is CAE/CFD. This study involves numerical analysis for the Zambil offshore project of a high-pressure drop control valve. ANSYS used a solver for offshore structures analysis. A high-pressure drop control valve, which transforms the power transfer of a system by reducing the inlet pressure of 345bar to the outlet pressure of 112bar, is a fundamental component in the offshore process. This study not only analyzes the relation between pressure drop and fluid velocity in a trim by using fluid analysis, but also examines the possibility of cavitation in a valve in addition to the plot for the extension of lifespan. It is demonstrated that the pressure drop from 345bar to 112bar is more feasible in the presence of the trim, which can induce a continuous and diminutive pressure drop in order to prevent cavitation in a high-pressure drop control valve.

• The KSFM Journal of Fluid Machinery
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• v.16 no.1
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• pp.32-39
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• 2013

The multi-stage control valve is one of the devices which controls cavitation and high pressure drop. To attain the high pressure drop, the conventional control valves adopted the multi-stage trim to avoid the occurrence of local cavitation in valves. This work studied the effect of divergence angle on the characteristics of multi-stage trim. Pressure drop and flow characteristics was calculated for the 1 passage of multi-staged trim by using the FLUENT 6.3.26. The result showed that the pressure drop is significantly influenced by the divergence angle of multi-stage trim. In addition, the pressure drop increased consistently as the Reynolds number and divergence angle increases.

• The KSFM Journal of Fluid Machinery
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• v.10 no.4
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• pp.61-70
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• 2007

Numerical analysis of three dimensional incompressible turbulent flows in LNG marine high pressure drop control valves was carried out by using the CFD-ACE from ESI-Group. In this study, flow characteristics of control valves with complex flow fields including cavitation effect were investigated. Simulation was performed on five models of control valve that had different orifice diameters of anti-trim and the size of valve. Comparing newly designed control valves for controling the occurrence of cavitation with the conventional valve, new valves showed a improved flow pattern with almost no cavitation.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.9
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• pp.863-871
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• 2013

Flow characteristics of velocity-control trim in a valve is investigated numerically with high pressure drop. A basic trim widely used for a valve in domestic powerplants is selected and designed for a baseline of velocity-control trim. The numerical analysis is focused on flow rate and cavitation with the basic trim. For a condition of high-pressure drop, pressure drop between inlet and outlet and fluid temperature are selected to be 18.1 MPa and $160^{\circ}C$, respectively, which are typical ones considering operating conditions adopted in powerplants. With this baseline model and condition, design changes are made for improvement of flow rate and cavitation phenomenon. For re-design, trim is divided into three zones in radial direction and design parameters of flow area, stage, and flow direction are considered in each zone. With these combined parameters applied to each zone, 4 models with design changes are proposed and their flow rates and cavitation areas are investigated. From comparison with those in the baseline model of a basic trim, proposed models show better performance in both flow rate and cavitation.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.4_2
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• pp.541-547
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• 2022

Before making a prototype, we predicted the inlet/outlet differential pressure and flow coefficient, which are the most basic design data for the valve through the design and numerical analysis of the trim, which is the most important in the localization development of the 1500Ib high differential pressure control valve used for boiler feed water. As a result, the design value and the analysis value were found to be about 98% similar. The flow field within the fluid velocity of 23m/s to prevent cavitation was also found. The result of the numerical analysis on thermal stress due to the characteristics of valves exposed to high temperatures showed that it was found to be about 18% less than the allowable stress of the bolt fixing the trim. When all loads such as pressure, self-weight, and vibration are applied, however, it is judged to go beyond the currently calculated thermal stress, exceeding the allowable stress.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3074-3079
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• 2007

The conventional control valves have been used at the locations occurring high differential pressure and high temperature which causes cavitation, flashing, severe vibration due to abrupt flow change, and sudden pressure drop. Previous studies concerning control valves focused to prevent damage of valve trim due to the internal leak and low flow rate. The newly designed helical trim of control valve has been installed at the location of high pressure change and high temperature in a power plant, and operated for evaluation. It is confirmed that the new control valve developed in this study generates flow characteristics in comparison with previous helical trim of control valves.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.8
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• pp.19-24
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• 2022

We developed a prototype from the design of a trim, which is the most important in the localization development of a 1500 Ib high-differential pressure-control valve used for boiler feedwater, and measured the flow coefficient, the most basic design data for valves. The following conclusions were drawn. The comparison of the design values of the flow coefficients for the existing X-trim and the multicore trim designed for localization development showed that they were almost identical, and the X-trim value was slightly lower. The comparison of the X-trim and multicore trim based on the valve flow coefficient test showed that they were generally similar, indicating no problem with the design. In the future, we plan to compare and analyze the flow paths for the X-trim and multicore trim via flow analysis.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.1
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• pp.131-139
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• 2022

The exchange of goods over the sea is a situation in which the amount of trade between countries is gradually increasing. In order to maintain the optimal operating condition, the ship maintains stability and optimal operating conditions by inserting or withdrawing ballast water from the ballast tank according to the loading condition of cargo capacity is also increasing. Control valves play an important role in controlling fluid flow in these pipes. When the flow rate is controlled using a control valve, problems such as cavitation, flashing, and suffocating flow may occur due to high differential pressure, and in particular, damage to valves and pipes due to cavitation is a major problem. Therefore, in this study, the cavitation phenomenon is reduced by installing orifices at the front and rear ends of the high differential pressure control butterfly valve to reduce the sudden pressure drop at the limiting part of the butterfly valve step by step. The flow coefficient according to the shape of the orifice, the degree of cavitation occurrence, and the correlation were analyzed using a CFD(Cumputational Fluid Dynamics), and an optimal orifice design for reducing cavitation is derived.