• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.05a
• /
• pp.813-814
• /
• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2010.05a
• /
• pp.1043-1044
• /
• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2010.11a
• /
• pp.713-714
• /
• 2010

• Tunnel and Underground Space
• /
• v.13 no.3
• /
• pp.225-234
• /
• 2003

The structures to be demolished have become diverse in types from reinforced concrete to steel. The demand for demolition of steel structures is recently increasing in Korea. Most of flexible linear-shaped charges for steel demolition are now imported from foreign countries. To determine the optimum parameters of design far domestic development of flexible linear-shaped charges, some basic experiments have been carried out and their results are summarized as follows; Copper is shown to be superior to aluminium and lead as a liner material. It is also proved that the optimum apex angle of liner is 90$^{\circ}$ in comparision with 45$^{\circ}$, 60$^{\circ}$ and 120$^{\circ}$ Adequate thickness of liners, standoff distance in terms of quantity of explosives are also examined. Explosives and liners are required to be plasticized in order to improve the bond between explosives and various shapes of steel structures.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.16 no.1
• /
• pp.37-41
• /
• 2020

The Nuclear containment building is a main safety-related structure that performs shielding and conservation functions to prevent highly radioactive materials from leakage to the outside environment in the case of various environmental conditions and postulated accidents. The containment building contains a reactor, steam generator, pressurizer, tank, reactor coolant system, auxiliary system and engineering safety system, and is designed so that highly radioactive materials above the limits specified in 10 CFR 100 do not escape to the outside environment in the case of LOCA(Loss of Coolant Accident) for instance. The containment metal liner plate(CLP) is a carbon steel plate with a nominal plate thickness of 6 mm, which functions as a mold for the wall and dome of the containment building when concrete is filled, fulfills airtightness to prevent leakage of seriously radioactive materials. In recent years, backside corrosion was found on the liner plate in some domestic nuclear power plants. The main cause of backside corrosion was unfilled concrete. In this paper, an inspection technique of assessing filling suitability for CLP backside concrete is developed. Results show that the validity of inspection technique for CLP backside concrete using vibration sensor is successfully verified.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.28 no.8 s.227
• /
• pp.1221-1228
• /
• 2004

The vertical roller mill is the important machine grinding and mixing various crude materials in the manufacturing process of portland cement. Table liner is one of grinding elements of vertical roller mill and is subjected to the cyclic bending stress by rollers load and the centrifugal force by rotation of table. It demands $4{\times}10^7$ cycle but has $4{\times}10^6{\sim}8{\times}10^6$ cycle. It fractures at the edge of grinding path of outside roller. The repair expense for it amounts to $30\%$ of total maintenance of vertical roller mill. Therefore, this study shows the fracture mechanism of table liner for vertical roller mill using HDM and fatigue analysis and makes the estimation for safety of vertical roller mill.

• Proceedings of the KSME Conference
• /
• 2008.11b
• /
• pp.2862-2867
• /
• 2008

High-temperature components of gas turbine operated for certain period of time can be reused by being repaired or rejuvenated. In case of the gas turbine combustion liners, the biggest and the most important one in the high-temperature components, come in a repair shop after operated for 8,000 or 12,000 hours according to the model and go through the repair and rejuvenation in order to be reused. A stated combustion liner is the first channel which has the combustion gas reached a nozzle from a fuel nozzle. Materials and coating properties of old and new model combustion liners were investigated. To repair these components after the visual inspection, the coatings of combustion liners were removed and then FPI(Fluorescent Penetrant Inspection), a kind of the NDI(Non-Destructive Inspection), was conducted. Damage patterns and the number of the damaged components were classified and analyzed based on data provided from the visual inspection over a long period of time. Focusing on the difference between old model and new model combustion liners, we analyzed the damage distribution and changes and consequently concluded that new model combustion liner would increase repair rate.

• Tribology and Lubricants
• /
• v.28 no.5
• /
• pp.233-239
• /
• 2012

The engine of a large ship operates under wet conditions using a fuel such as bunker C oil, which includes sulfur and many impurities. A cylinder liner made of cast iron is very susceptible to damage such as scuffing on the surface. This scuffing can reliably be attributed to the destruction of the oil film and the corrosion wear caused by water and sulfur included in the fuel, along with abrasion impurities and poor lubricants. In this study, a reciprocating friction and wear test was carried out with a cast iron specimen, which was used to simulate an engine cylinder in a corrosive environment. Base-oil and stirred oil containing distilled water, NaCl solution, and dilute sulfuric acid were used as lubricants. The friction surface was analyzed using a microscope and EDAX, and the friction coefficient was measured using a load-cell under each experimental condition. We then attempted to investigate the damage to the cylinder liner using the results.

• Corrugated packaging logistics
• /
• v.4 no.16
• /
• pp.139-141
• /
• 1997

• Proceedings of the Korean Nuclear Society Conference
• /
• 2003.05a
• /
• pp.408.1-408.1
• /
• 2003