Seismic Test Result of Motor-Operated Butterfly Valve Actuators for Nuclear Power Plant

Seismic tests were carried out to confirm the operability limit acceleration for a standard motor-operated butterfly valve actuator in three excitation directions. Based on the results, seismic brackets that can operate valves even in three directions at 20 × 9.8 m/s2 or more were designed in three representative models. For the model subjected to the seismic test, we mounted the designed seismic bracket and confirmed the operability of the butterfly valve actuator by carrying out vibration tests in three directions at 20 × 9.8 m/s2. We used these results and previously reported motor-operated valve actuator seismic test results to creat a revision (draft) of the earthquake resistance evaluation methods.

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Seismic Test Result of Air Operated Valve Actuators for Nuclear Power Plant (Air Operated Globe Valve (Diaphragm Type) and Air Operated Butterfly Valve (Lever Type) )

10.1115/1.0000059v ◽

2021 ◽

Author(s):

Yoshitaka Tsutsumi ◽

motoaki fuji ◽

Yoshitsugu Nekomoto ◽

Shigeki Suzuki ◽

Yoshinao Matsubara ◽

...

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Butterfly Valve ◽

Globe Valve ◽

Test Result

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Shrinkage Cracking Resistance Property of Self-Compacting Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.383 ◽

2011 ◽

Vol 250-253 ◽

pp. 383-387

Author(s):

Xian Yu Jin ◽

Chuan Qing Fu ◽

Nan Guo Jin ◽

Fan Ge ◽

Yi Bing Zhao

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Design Theory ◽

Test Results ◽

Self Compacting Concrete ◽

Cracking Resistance ◽

Shrinkage Cracking ◽

Resistance Property ◽

Mix Proportion

Based on the project requirement of a nuclear power plant, using the method of free shrinkage test and ring cracking test, shrinkage cracking resistance property of grade C35 and C50 self-compacting concrete (SCC) with the optimized mix proportion was studied. The test results between SCC and ordinary vibrated concrete afforded by nuclear power plant project with the same grade were compared. The results indicated that the shrinkage cracking resistance property of SCC is prior to the ordinary vibrated concrete with the same strength grade. This kind of SCC can satisfy the nuclear power plant project, also the test results can be a reference of SCC design theory.

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Strength and Toughness of Steel Fiber Reinforced Heavy Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.512-515.2908 ◽

2012 ◽

Vol 512-515 ◽

pp. 2908-2913 ◽

Cited By ~ 2

Author(s):

Yu Cheng Kan ◽

Hsuan Chih Yang ◽

Kuang Chih Pei

Keyword(s):

Experimental Study ◽

Compressive Strength ◽

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Iron Ore ◽

Steel Fiber ◽

Test Results ◽

Spent Fuel ◽

Normal Concrete

This paper presents an experimental study dealing with the toughness of heavy concrete based on the ASTM C1018. Mixtures including 0%, 0.5%, 1.0% and 1.5% of steel fiber content by volume are designated, which are developed based on a mixture used in Kuosheng nuclear power plant in Taiwan. Metallic aggregates of iron shots and iron ore take 48.8% by volume in that mixture. Test results reveal that the compressive strength and rupture modulus of heavy concrete turn out higher than those of normal concrete. In addition, flexural toughness of heavy concrete grow with the steel fiber fraction, which is valid and appropriate for construction of shielding structure and spent fuel cask.

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Life Prediction Model for Nuclear Power Plant Intake Structure Exposed to Chloride Environment Based on Similarity Principle

Volume 1: Beyond Design Basis; Codes and Standards; Computational Fluid Dynamics (CFD); Decontamination and Decommissioning; Nuclear Fuel and Engineering; Nuclear Plant Engineering ◽

10.1115/icone2020-16002 ◽

2020 ◽

Author(s):

Sen Chen ◽

Zhen Wang ◽

Jiangtao Zhang ◽

Dahua Cai ◽

Jiyun Zhou

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Salt Spray ◽

Chloride Ion ◽

Ion Concentration ◽

Test Results ◽

Ion Diffusion ◽

Similarity Principle ◽

Intake Structure

Abstract Three environmental simulation experiments for accelerating the chloride ingress were designed based on the similarity principle and the actual Nuclear Power Plant (NPP) intake structure service environment parameters including alternate drying-wetting condition, immersion condition and salt spray condition. Different experiment conditions were designed for each three-simulation experiment condition based on the similarity principle. The temperature, chloride ion concentration and dry-wet cycle time ratio were selected parameters for alternation wetting-drying experiments. The temperature and chloride ion concentration were selected parameters for the salt spray experiment and immersion experiment. The distribution of chloride ion concentration along the depth of the concrete samples were measured every 30 days. The testing results showed that chloride ion diffusion depth is maximum under the dry-wet cycle test, chloride ion diffusion depth is minimum under salt spray test. The curves of the chloride ion concentration along depth increased firstly and then decreased, which is consistent with the two-dimension diffusion law. Finally, a life prediction model that can be used to predict the concrete structure of the existing coastal nuclear power plant was developed based on the test results and field test results.

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Numerical Study on Cavitation at Low Opening Degrees and Seismic Analysis for 3-axial Eccentric Butterfly Valve for Nuclear Power Plant

The KSFM Journal of Fluid Machinery ◽

10.5293/kfma.2020.23.3.042 ◽

2020 ◽

Vol 23 (3) ◽

pp. 42-47

Author(s):

Seung Eon Jang ◽

Seong Hwi Jo ◽

Young Woon Jang ◽

In Soo Jeon ◽

Won Hee Lee ◽

...

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Seismic Analysis ◽

Numerical Study ◽

Butterfly Valve

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Structural Safety Analysis Based on Seismic Service Conditions for Butterfly Valves in a Nuclear Power Plant

The Scientific World JOURNAL ◽

10.1155/2014/743470 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Sang-Uk Han ◽

Dae-Gyun Ahn ◽

Myeong-Gon Lee ◽

Kwon-Hee Lee ◽

Seung-Ho Han

Keyword(s):

Finite Element ◽

Power Plant ◽

Nuclear Power Plant ◽

Finite Element Model ◽

Nuclear Power ◽

Dynamic Properties ◽

Element Model ◽

Structural Safety ◽

Butterfly Valve ◽

Design Response Spectrum

The structural integrity of valves that are used to control cooling waters in the primary coolant loop that prevents boiling within the reactor in a nuclear power plant must be capable of withstanding earthquakes or other dangerous situations. In this study, numerical analyses using a finite element method, that is, static and dynamic analyses according to the rigid or flexible characteristics of the dynamic properties of a 200A butterfly valve, were performed according to the KEPIC MFA. An experimental vibration test was also carried out in order to verify the results from the modal analysis, in which a validated finite element model was obtained via a model-updating method that considers changes in thein situexperimental data. By using a validated finite element model, the equivalent static load under SSE conditions stipulated by the KEPIC MFA gave a stress of 135 MPa that occurred at the connections of the stem and body. A larger stress of 183 MPa was induced when we used a CQC method with a design response spectrum that uses 2% damping ratio. These values were lower than the allowable strength of the materials used for manufacturing the butterfly valve, and, therefore, its structural safety met the KEPIC MFA requirements.

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Study on the Operability Margin Variation of Butterfly Valve

Volume 2: Fora, Parts A and B ◽

10.1115/fedsm2007-37512 ◽

2007 ◽

Author(s):

Ju Yeop Park ◽

Gong Hee Lee ◽

Do Hwan Lee

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Finite Thickness ◽

Loss Coefficient ◽

Hydrodynamic Effect ◽

Butterfly Valve ◽

Design Basis ◽

Operating Margin ◽

Torque Coefficient

Design basis capability of safety-related butterfly valve of nuclear power plant should be verified due to the regulation of Korea. Therefore, based on the results from the torque coefficient of thin symmetric plate, the nuclear utility has performed the engineering calculation to determine the required torque for operating a butterfly valve and the margin of operability at design basis condition. However, recent research showed that the torque coefficient of the thin symmetric plate used before is rather larger than newly determined one. Therefore, in the present study, the effect of change in the torque coefficient of thin symmetric plate on the operating margin is investigated. First, the recently determined valve loss coefficient of thin symmetric plate is modified at near valve full open position to reflect a finite thickness of valve disk. Second, the torque coefficient of symmetric disk butterfly valve is determined from the loss coefficient and the torque coefficient of thin symmetric plate and using this, the torque coefficient of butterfly valve with asymmetric disk is also deduced. Then, the variation on the hydrodynamic torque of butterfly valve is quantified and the operating margin variation of safety-related butterfly valve is determined. Calculations of the operating margin are performed for 10 butterfly valves of Uljin 6 nuclear power plant of Korea, which have all asymmetric valve disks. As expected, the hydrodynamic torque which is proportional to the torque coefficient is reduced and the resulting margin of operability is improved for opening safety direction. The margin improvement amounts to from 6.0% to 142.9% for valves considered. For closing safety direction, although the hydrodynamic torque is also reduced, the total dynamic torque due to overall hydrodynamic effect is increased from 1.1% to 63.0% on the contrary. This increase is because the hydrodynamic torque assists valve closing. Despite of these increases in the total dynamic torque, the operability margins of closing direction do not change at all. The reason is that the required torque for operating valve is determined not by the total dynamic torque but by the total seating torque which is more dominating. In conclusion, the margin improvement is significant for opening otherwise the margin deterioration is slight for closing when the torque coefficient is reduced.

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