• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.4
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• pp.28-35
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• 2007

Currently, most of all valves using at the semiconductor & LCD manufacturing process are packless type. Such valves are needed to have the functions to protect perfectly from the leakage of fluid by using bellows and diaphragm instead of the grand packing. But not only those valves made in Korea are not available at this point, but also advanced foreign manufacturers do not open enough their data on the basic technology. Otherwise although they open the data a little, they are almost data about stainless steel for pneumatic valves. In this paper, it was focused on the fluid valves for chemical & DI water based on the data of steel valves which are already using commercially. And also this study concentrated to collect the basic developing data of Eco-On/Off diaphragm valve by ourselves.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.4
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• pp.3-7
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• 2007

The valve is used on control of flow in a ship. Flow coefficient of valve is very importance in the design of valve. In this paper, three-dimensional computer simulations by commercial code CFX were conducted to observe the valve type and to measure flow coefficient when valves with various angles and uniform incoming velocity were used in a piping system. By contrast, a group of experimental data is used to compare with the data obtained by CFX simulation to investigate the validity of numerical method.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.373-377
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• 2003

Recently, advanced manufacturing systems with high speed and intelligence have been developed for the betterment of machining ability. In this case, reliability prediction work with motion characteristic evaluation of sliding cover(C-plate, Bellows, etc) has also important role from design procedure to manufacturing and assembly process. Accordingly in this study, H/W test-bed system for reliability evaluation of sliding cover has been developed to obtain proper reference data for design of new model, prevention trouble (failure mode), and improvement of quality and lift cycle extremely for advanced mother machinery.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.514-517
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• 1995

A new stroke output control algorithm with a fuzzy logic for an electrohydraulic left ventricular assist device(EH-LVAD) was developed. The EH-LVAD pumps out blood from left atrium actively. Excessive suction of blood may cause fatal damage in left atrium. The LVAD has to provide a maximal stroke output without collapse of left atrium. In this study a new fuzzy algorithm for predicting and detecting suction and doing proper action on LVAD without using an extra pressure sensor but with bellows pressure signal and motor current signal is developed. The performance of the fuzzy control algorithm is demonstrated by the results from mock circulatory experiments.

• Proceedings of the KSR Conference
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• 2000.11a
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• pp.468-475
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• 2000

An air spring was accepted for rail vehicle secondary suspension to reduce and absorb tile vibration and the noise. The air spring for the electric railway was developed with domestic technology, which consisted of a cord reinforced rubber bellows, a upper plate, a lower plate and a stopper rubber spring The fatigue test was conducted in laboratory by using servo hydraulic fatigue testing system to verify the durability. And to guarantee the adaptation of this air spring, the ride comfort and the air pressure variation were measured in train test on Boondang line.

• 한국전산유체공학회:학술대회논문집
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• 2005.04a
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• pp.100-103
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• 2005

This work discusses the numerical analysis, the design and experimental test of the SMA (Shape Memory Alloy) actuator along with its capabilities and limitations. Convection heating and cooling using water actuate the SMA element of the actuator. The fuel such as propane, having a high energy density, is used as the energy source for the SMA actuator in order to increase power and energy density of the system, and thus in order to obviate the need for electrical power supplies such as batteries. The system is composed of a pump, valves, bellows, a heater (burner), control unit and a displacement amplification device. The actuation frequency is compared with the prediction obtained from numerical analysis. For the designed SMA actuator system, the results of numerical analysis were utilized in determining design parameters and operating conditions.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.776-781
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• 2001

Internal pipes technology for LNG Storage tank developed because of the perceived safety risk of having an opening near the base of the shell. This is because the shell at this point is the most highly stressed component of the primary containment. other, secondary, problems arise because the movement of the tank in this region is also at a maximum. This requires the use of bellows either in the interspace or on the outside of the outer tank. Therefore the internal pipe, through the roof, solves these problems. The loading conditions calculated from design concept are then used to perform a pipe stress analysis. As well as determining the stresses in the internal pipe and checking against allowable stress, it determines the reaction forces at the support positions.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1990-1992
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• 2000

Isolated phase bus is, as a special bus which allows large current from a generator to main transformer, composed of main conductor, enclosure and auxiliary equipments such as insulating bellows, bus elbows, support insulator, etc. To develop this kind of high power devices, it is required to secure the technique of selection of conducting and insulating materials, basic arrangement skills, and analysis on eddy current which causes temperature increase in enclosures. By the way, these techniques are based on the analysis of electromagnetic phenomena for high voltage and large current. In this study, an electromagnetic field analysis program is developed and applied to the isolated phase bus. which could be the basic numerical method for the analysis design and modifying isolated phase bus.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.79-84
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• 2010

The supply system module of the liquid rocket engine has been developed, which consists of the various supply system components such as pipes, orifices, elbows, bellows, valves and flanges. This module can size the components and calculate pressure drops between them. For the assembly of the supply system components, the supply system module can evaluate the number of the components, total pressure drop, outlet pressure and total system weight.

• The Journal of Korea Robotics Society
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• v.16 no.1
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• pp.23-28
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• 2021

The gripper with a soft pneumatic actuator uses a soft material, unlike the gripper that uses a rigid body, so it is safer and lighter to interact with objects without advanced control technology. Among the soft pneumatic actuators that have been studied, PneuNets actuators have bellows shape, which enable quick operation and complete bending with only small material deformation at low pressure. In this study, we suggested improved form of PneuNets actuators to obtain the performance of the soft actuator that a larger bending angle and larger bending force at a small pressure. An experiment was designed and conducted to measure the bending angle and bending force according to the pressure. As a result, it was confirmed through experiments that the improved model has a maximum bending angle at a pressure of 5 kPa lower than that of the previous model, and a maximum bending force of 1.97 times at the same pressure.