• 연구논문집
• /
• s.34
• /
• pp.47-58
• /
• 2004

Power plants rely on air operated valves for the proper operation of many plant system. Many significant problems arise in vital systems of power plants due to air operated valve failures. This paper deals with the diagnosis technique and data acquisition method of an AOV actuator peformance. We constructed AOV diagnosis system and performed some tests to find out whether an AOV actuator was properly designed.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.32 no.5
• /
• pp.400-405
• /
• 2008

Air-operated valve is one of principal valves that are used to control fluid flow in nuclear power plants. It is necessary to evaluate periodically the performance of the AOV(Air-Operated Valve) which is used for controlling flow and pressure in nuclear power plants. In this study, we developed the integrated program HAES including hardware system to evaluate the performance of AOV. HAES(HANVIT AOV Evaluation System) consists of many modules such as valve information, thrust and torque analysis, actuator analysis, weak analysis and margin analysis. We applied with the test valve and showed that results evaluated by HAES is similar to those offered in the plant.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2004.11a
• /
• pp.945-948
• /
• 2004

A free vibration analysis of air-operated valve(AOV) is investigated. The vibration characteristics of AOV with size variations are studied. The effects of inner pressure on the natural frequencies are also studied. The analytical results are compared with expermental results.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.1080-1082
• /
• 2003

To develop a reliability analysis program applied to the diagnosis for air operated valve's integrity. we collected, analyzed AOV failure data from foreign and domestic nuclear power plants, and classified whole subjects of this program into several groups according to type and size. We established a theoretical basis using Lognormal Distribution and Bayesian Theory to develop analysis methodology. The result of this program was applied to the calculation of operational unavailability of AOV, and the effect of AOV's failure. Also this program can be applied to the development of diagnostic technique considering AOV environment (temperature, pressure), and setting-up maintenance cycle.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1766-1769
• /
• 2005

Air-operated valve(AOV) is one of principal valves that are using to control fluid flow in nuclear power plants. AOV is suffered from damage and malfunction by the abrasion, corrosion and vibration of valve parts under the long time operation. This mechanical trouble and malfunction of valve is critical for the safety of power plant. So a periodic diagnosis for safety of power plants is inevitable to guarantee the safety of the power plant. But depending on the type of the actuator and valve body, various types of AOV exist. In this study, It is developed the diagnostic system that users of power plants are easy to handle in this paper.

• Proceedings of the KSME Conference
• /
• 2005.11a
• /
• pp.109.2-109.2
• /
• 2005

• Nuclear Engineering and Technology
• /
• v.36 no.3
• /
• pp.210-218
• /
• 2004

In the interest of nuclear power plant safety, a self-diagnostic monitoring system (SDMS) is needed to monitor defects in safety-related components. An air-operated valve (AOV) is one of the components to be monitored since the failure of its operation could potentially have catastrophic consequences. In this paper, a model of the AOV is developed with the parameters that affect the operational characteristics. The model is useful for both understanding the operation and correlating parameters and defects. Various defects are introduced in the experiments to construct a fault library, which will be used in a pattern recognition approach. Finally, the validity of the fault library is examined.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1770-1773
• /
• 2005

The performance evaluation of AOV(air-operated valve) requires the processes to confirm the actuator system capability. It is necessary to evaluate the thrust of the air actuator for the margin evaluation. In this paper, to evaluate and analysis the air actuator, the performance test system and operating program are developed. This system is composed of several sensors such as pressure sensor, LVDT, and LoadCell which are used to get the data for evaluation. The LabVIEW was used for developing the operating program. The test system and operating program are proved through the actual test of the diaphragm actuator.

• Proceedings of the KSME Conference
• /
• 2008.11b
• /
• pp.2616-2620
• /
• 2008

AOV used fluid capacity and fluid pressure control in nuclear power plant with heating power plant. AOV structures safely must be secured the reliability and a safety of the atomic power plant. but, AOV where is used from domestic is using the product of the overseas enterprise. The AOV design and maintenance technique is insufficient. Therefore According to ASME designed AOV, The performance test resultant fluid leakage did not occur and AOV design was satisfactory.

• Proceedings of the KSME Conference
• /
• 2008.11a
• /
• pp.485-490
• /
• 2008

Under localization developing for the control valve of the safety grade Q Class 1 which is established in the atomic power plant followed ASME Code and important parts (Body, Yoke, Bonnet, Actuator) design and produced. In order to verify this analyzed the earthquake stress of AOV. AOV the above of 33Hz occurred from fIrst mode, the earthquake stress occurred from inside the yield strength of the material.