• Transactions of the Korean hydrogen and new energy society
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• v.33 no.4
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• pp.383-390
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• 2022

Appropriate explosion proof electrical equipment should be installed in hazardous areas. In areas where hydrogen is handled, explosion proof electrical equipment adjacent to the hydrogen handing facility must be reviewed for selection of gas group IIC (or IIB+H₂) equipment. When selecting explosion proof electrical equipment for the flammable substance handling facility in areas where hydrogen and flammable substance are handled, the method to avoid gas group IIC (or IIB+H₂) equipment has been suggested by using the operating pressure of the hydrogen handling facility. When the operating pressure of the outdoor hydrogen handling facility is 1.065 MPa or less, it has been confirmed that there is no need to install gas group IIC (or IIB+H₂) equipment for the flammable substance handling facility adjacent to the hydrogen handling facility. And the method of selecting explosion proof electrical equipment for the flammable substance handling facility has been suggested as a flowchart, so it will be able to be utilized when selecting appropriate explosion proof electrical equipment.

• Journal of the Korean Society of Safety
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• v.7 no.1
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• pp.57-64
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• 1992

This study is conducted for both examination of theory for electrical explosion protection and investigation of operation condition of selected95 companies, to eseblish the safety standard of explosion protection for eletrical eqiupments that explosion is possible.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.3
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• pp.474-478
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• 2018

The use of metals such as aluminum and titanium and the related industrial facilities have been continuously increasing to meet the requirements of the improvement of high-tech products due to the development of industry, and explosion of metal dust. Semiconductor process Metal dust is essential, but research is insufficient. The purpose of this study is to identify risk by analyzing the quantitative risk such as maximum explosion pressure and minimum explosion concentration applied international test standard in order to select the semiconductor process facilities handling dust and to predict possible risk of accidents.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.474-475
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• 2007

Wire electrical explosion(WEE) has been used for the production of fine metal particles. In WEE, electrical powder was stored and compressed into capacitor and released to produce fine particles through evaporation and condensation. In this study, the effect of applied voltage on the size of copper powders was investigated. High tension was added up to the explosion device by dividing 4 steps. At voltages lower than 5.2 kV, the fraction of powders finer than $44{\mu}m$ was almost negligible. The effectiveness of explosion increased sharply with increased voltage over 5.8 kV. At the highest voltage of 6.4 kV, more than 80% of explosion products were finer than $44{\mu}m$.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.110-113
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• 1994

In the hazardous areas where explosive substances in the form of gases, vapor or mists exist, electrical apparatus and installations must be of explosion-proof construction to prevent or limit the danger of the ignition of potentially explosive atmosphere. In Korea, six types of protection have been specified in the government regulations at present: flameproof enclosure, pressurization, oil immersion, increased safety, intrinsic safety, and special types. If electrical apparatus are made of explosion-proof construction in a way other than five above-mentioned types, and their performance is tested and approved by the reponsible authorities, they may be categorized as special type apparatus. In this paper, we introduced a special type of explosion-proof electrical apparatus, called non-incendive type, and presented its constructional requirements. We also investigated evaluation methods of non-incendive type apparatus to assure the explosion-proof performance, and proposed a new classification method of hazardous areas using probabilistic concept.

• Journal of Powder Materials
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• v.23 no.6
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• pp.409-413
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• 2016

Electrical wire explosion in liquid media is a promising method for producing metallic nanopowders. It is possible to obtain high-purity metallic nanoparticles and uniform-sized nanopowder with excellent dispersion stability using this electrical wire explosion method. In this study, Ni-Fe alloy nanopowders with core-shell structures are fabricated via the electrical explosion of Ni-Fe alloy wires 0.1 mm in diameter and 20 mm in length in de-ionized water. The size and shape of the powders are investigated by field-emission scanning electron microscopy, transmission electron microscopy, and laser particle size analysis. Phase analysis and grain size determination are conducted by X-ray diffraction. The result indicate that a core-shell structured Ni-Fe nanopowder is synthesized with an average particle size of approximately 28 nm, and nanosized Ni core particles are encapsulated by an Fe nanolayer.

• Journal of the Korean Society of Safety
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• v.35 no.2
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• pp.8-16
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• 2020

In Article 311 of the Regulation on Occupational Safety and Health Standards requires the use of Korean Industrial Standards Act in accordance with the Industrial Standardization Act. However, the classification, inspection, maintenance, design, selection, and installation of explosion hazard locations for explosion and explosion prevention and internalization of 'safety' in the performance maintenance phase of electrical machinery and equipment There is no technical and institutional management plan for remodeling and alteration. Analysis of actual conditions and problems related to the installation, use, and maintenance of explosion-proof equipment, comparative analysis of domestic and international technical standards and systems, technical, institutional and administrative systems and systems related to installation, use, and maintenance of explosion-proof equipment, technical personnel and qualifications, etc. It is to propose legislation, system improvement, and technical standard establishment related to the maintenance of explosion-proof facility performance through improvement of the necessity and feasibility study for establishment of the legal status of the management site and management plan. As technical measures, KS standard revision (draft), KOSHA guide (draft) and explosion-proof facility performance maintenance manual were presented. In addition, the institutional management plan proposed the revised rule on occupational safety and health standards, the revised rule on the restriction of employment of hazardous work, and the manpower training program related to the maintenance of explosion-proof facilities and the qualification plan. Enhance safety at the installation, use, and maintenance stage of explosion-proof structured electrical machinery. It is expected to be used to classify explosion hazards, select related equipment, and to update and standardize standards related to installation, use and maintenance.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.9
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• pp.452-455
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• 2006

The technology of wire explosion have been used to product nanopowders. A new concept was proposed to produce metallic nanosized powders, which is wire explosion in liquid media. We have exploded the Ag or Cu wires of diameter of O.3mm, 40mm long, in the de-ionized water or acetone, respectively. Electrical energy of 1.1kJ was stored in 10uF capacitor and released to the wires through a triggered spark gap switch. The process was observed by high-speed camera. Those images showed that the powders were generated by vapor condensation in the shell formed by shock wave in the water. The particles were directly dispersed into the water with collapse of the shell. The sizes of Ag and Cu nanopowders were evaluated to 35nm and 17nm, respectively.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1453_1454
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• 2009

This paper examines the characteristics of ZnO varistor to prevent from thermal explosion. We carry out performance evaluation of electrical characteristics on ZnO varistor. we will develop ZnO varistor Prevented from thermal explosion using test result of this paper.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.12
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• pp.1836-1843
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• 2017

In this paper, we investigated fire cases those are believed to be caused by explosion of a electrolytic motor start capacitor. Using two types of commercially available electrolytic motor start capacitors, capacitor current and the possibility of capacitor explosion were tested. And the ignition possibility of the internal material leaked from a capacitor was also tested. In addition, experiments were conducted to see if the fire could spread when a capacitor was exposed to an external flame. From our test we observed that the current of the electrolytic motor start capacitor rose continuously to a certain level by product, if the capacitor was continuously energized with working voltage, and then the capacitor was exploded. The gas and liquid leaked from the capacitor by the explosion could ignite by an electric arc and an external flame. The capacitor current at explosion was different product by product, but each product had a certain current level at explosion. And the increase rate of the capacitor current until explosion was 24% and 31% for the products used in the experiment. We proposed the capacitor explosion prevention method that cuts off power when the capacitor current rises to a certain threshold level. The proposed method can be used if the current of the applied electrolytic motor start capacitor rises continuously and then the capacitor is exploded at a certain current level when the capacitor is energized continuously.