• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.11
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• pp.109-114
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• 2019

Hydraulic pumps are widely used in fields such as machinery manufacturing, engineering and construction. Although the research on hydraulic engineering is mature, it is still necessary to examine various performance aspects in detail for specific applications. This paper will focus on the hydraulic pump used in special construction machinery that needs high temperature and high pressure resistance. It will analyze the theoretical design, structure and thermal characteristics of the pump system using the Fundamentals of Engineering (FE) method, and will measure the key tolerance parameters of the hydraulic pump to ensure the accuracy of the machining. Through this research, a good design method for the linear reciprocating type of hydraulic pump can be summarized.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.10a
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• pp.76-85
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• 1997

Recently, bent-axis-type axial piston pumps drived by rod being in extensively used in the world, because of simple design, lightweight, effective cost. So, to guarantee the quality of bent-axis-type axial piston pumps drived by rods, it is necessary to know chracteristics of the forces applied to rods and the driving mechanism of rods. But, as they perform both reciprocating and spinning motions, it is difficult to understand driving mechanism. In this paper, I explained the theoretical driving mechanisms of cylinder block drived by rods through geometric method and the characteristics of the forces applied to them.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.486-489
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• 2003

To reduce lateral force of traditional plunger type piston in the swash plate type hydraulic piston pumps and motors, we have proposed rod type piston with ball joint on both ends. We have studied the theoretical reaction force on two types of piston moving in the cylinder block bore. and made an experiment for the resistance force measurement on a reciprocating motion of plunger and rod type piston, changing the test condition such as swash plate angel and supply oil pressure and so on. As a result. a rod type piston has more smaller resistance force, about 29%. than a plunger type one.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.4
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• pp.113-118
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• 2021

In this study, localized development of a submerged cryogenic pump for use in LNG containers is conducted with large-sized commercial vehicles as the target. The submerged pump installed in an LNG storage container is the key module that supplies fuel to the engine through the reciprocating motion of a piston. Research and development on 660-L fuel containers is performed herein. The target is to achieve a mileage of 600 km or more by applying it to major NGV vehicles worldwide. In this manner, the present study aims to verify the operating mechanisms of the major parts of currently advanced products through reverse engineering in the early development process and draw basic design data.

• Tribology and Lubricants
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• v.14 no.4
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• pp.51-57
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• 1998

Recently, bent-axis-type axial piston pumps driven by rods being in extensively used in the world, because of simple design, lightweight, effective cost. So, to guarantee the quality of bent-axis-type axial piston pumps driven by rods, it is necessary to know characteristics of the driving mechanism of rods. But, as they perform both reciprocating and spinning motions, it is difficult to understand driving mechanism. In this paper, I studied the theoretical driving mechanisms of cylinder block driven by rods through geometric method. I found that the cylinder block was driven by one rod in limited area and the driving area was changed by rod's tilting angle and cylinder block's swivel angle.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.422-425
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• 2009

A sea water source cascade heat pump was designed and tested in this study. The system was designed to perform a single stage operation in summer, as well as a cascade operation in winter to ensure the high temperature lift. A steady-state simulation model was developed to analyze and optimize its performance. The simulation results show that the R717 exhibits best performance among combinations considered in this study. A R410A also exhibits the highest performance among HFCs with the smallest compressor displacement. A 15-RT R410A-R134a pilot system was installed in the 5-story commercial building at Samcheok City by the East Sea. A scroll type R410A compressor, a reciprocating type R134a compressor, plate type condenser/evaporator/ cascade heat exchanger and two electronic expansion valves were used to build a pilot. A titanium plate type heat exchanger is also used for the heat exchanging with a sea water. The heat source/sink water is supplied from the well below the seashore in the depth of 5 m. In the initial test of the system, supply water temperature was rising up to $67^{\circ}C$ using a sea water heat source of $9^{\circ}C$, while an ambient temperature was $4.5^{\circ}C$.

• Proceedings of the KOSOMBE Conference
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• v.1990 no.05
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• pp.1-6
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• 1990

A new version of moving actuator electromechanical total artificial heart was designed to improve total efficiency, durability, and fitting inside thoracic cavity. As compared with our present type of the rolling cylinder actuator, this new model has a pendulum-type actuator with reciprocating motion around the fixed circular path, connected through the gear mechanisms to the motor. By using this mechanism, the efficiency and durability could be improved by replacing sliding mechanism with rolling contact elements. Also, the height of the pump could be decreased from 9cm to 7cm with static stroke volume 65cc. With these improvements, we have implanted this new pump in human size animal (less than 70Kg weight).

• Journal of Biosystems Engineering
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• v.28 no.5
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• pp.395-402
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• 2003

Standard ginseng seedling, selected after one year's rearing in the seedling bed has been conventionally transplanted in Korea. Recently, the direct seeding areas have been increasing to product high quality ginsengs for red-ginseng processing. Reciprocating push-rod brush, holed-roller and vacuum suction seeders, planting with 30 ${\times}$ 30mm spacings and adjustable to the folds were designed and theirs performances were evaluated. The developed three types of seeders reliably performed at the success rate over 95% with less than 10% in slip rate, and could be used a seeder for the greater spacings by adjusting metering parts. The research concluded that the vacuum suction seeder was the most feasible and practical with the greatest metering success and the least slip among three type seeders of the reciprocating push-rod brush, holed-roller and vacuum suction seeders. The vacuum suction seeder holds a seed with each needle nozzle using the negative pressure created by a vacuum pump. The capacity was 24.5 times greater than a man power at the speed of 5 m/min.

• Current Photovoltaic Research
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• v.9 no.2
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• pp.51-58
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• 2021

Solar water pumping system (SWPS) is reliable and beneficial for Indian farmers in irrigation and crop production without accessing utility. The capability of easy installation and deployment, makes it an attractive option in remote areas without grid access. The selection of portable solar based pumps is pertaining to its longer life and economic viability due to lower running cost. The work presented in this manuscript intends to demonstrate performance analysis of portable systems. Consequent investigation reveals PSWS as the emerging option for rural household and marginal farmers. This can be attributed to the fact that, a considerable portion (around 45.7%) of the country's land is farmland and irrigation options are yet to reach farmers who entirely rely on rain water at present for harvesting of the crops. According to census 2010-2011 tube wells are the main source for irrigation amongst all other sources followed by canals. Out of the total 64.57-million-hectare net irrigation area, 48.16% is accounted by small and marginal holdings, 43.77% by semi-medium and medium holdings, and 8.07% by large holdings. As per 2015-16 census data, nearly 100 million farming households would struggle to make ends meet. The work included in this manuscript, presents the performance of different commercial brands and different technologies of DC surface solar water micro pumping systems have been studied (specifically, the centrifugal and reciprocating type pumps have been considered for analysis). The performance of the pumping systems has been analyzed and data is evaluated in terms of quantity of water impelled for specific head. The reciprocating pump has been observed to deliver the best system efficiency.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1353-1357
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• 2008

A sea water source cascade heat pump was designed and tested in this study. The system was designed to perform a single stage operation in summer, as well as a cascade operation in winter to ensure the high temperature lift. A steady-state simulation model was developed to analyze and optimize its performance. The simulation results show that the R717 exhibits best performance among combinations considered in this study. A R410A also exhibits the highest performance among HFCs with the smallest compressor displacement. A 15-RT R410A-R134a pilot system was installed in the 5-story commercial building at Samcheok City by the East Sea. A scroll type R410A compressor, a reciprocating type R134a compressor, plate type condenser/ evaporator/ cascade heat exchanger and two electronic expansion valves were used to build a pilot. A titanium plate type heat exchanger is also used for the heat exchanging with a sea water. The heat source/sink water is supplied from the well below the seashore in the depth of 5 m. In the initial test of the system, supply water temperature was rising up to $67^{\circ}C$ using a sea water heat source of $9^{\circ}C$, while an ambient temperature was $4.5^{\circ}C$.