• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.91-93
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• 2009

A large steel ingot needs to be larger and larger in size and an ultra high clean, no defect in quality with a low hot top ratio for the resent heavy industry. The demands are very difficult to achieve simultaneously because of their contradictive effect to each other in results. In this study, 30ton steel ingot was cast in a foundry with an optimized design parameter of cast mold and cast process conditions for the low hot top ratio, 12%. The cast ingot was analyzed in macro defect, segregations, and cleanness. No macro defect was founded in central surface of the ingot. The degree of segregation and cleanness are in the controlled range with a sound quality.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.43-45
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• 2008

According to industrial development, Ingots are more large and various. In particular large STS ingot. The probability of shrinkage cavity occurrence is higher than carbon steel and alloy steel. To manufacture ultra clean steel the technical development is nearly necessary for example controlling inclusions and total [H]. In this study, after measured the mold temperature and adjusted thermo conductivity of STS steel and compared existing mold to new one with CAE. As a result, the new mold more reduced than existing mold for the probability of shrinkage cavity occurrence.

• Journal of the Korean housing association
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• v.8 no.3
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• pp.219-230
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• 1997

Lack of technical standards, specification and inadequate execution in masonry wall construction in Korea lead to produce serious flaw problems such as crack, efflorescene, and upset etc.. The purpose of this paper is to present the practical details for Masonry cavity wall construction to prevent rain penetration and to accommodate differential movement between the inner and outer wythes of cavity walls. Considering rain penetration and differential movement of both wythes of cavity walls, provision of an adequate air space, an airtight back-up wall, clean cavity with weepholes and vents, properly positioned flashing, tie and shelf angle etc. depend on the cavity wall types will help ensure good performance. The present details included noncorrosive hot dip galvanized steel or stainless steel for metal components, plastic and ultra violet resistant polypropylene Copolymer for other components was taken into account the construction method and several types of cavity walls in Korea

• Journal of Powder Materials
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• v.3 no.4
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• pp.227-232
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• 1996

(i) The development of a metallurgical bond during the spray forming of clad products has offered the possibility of manufacturing large rolls, including those used in hot and cold strip mills. Small rolls are already being produced in Japan. (ii) Technical developments, including the use-of-multi-atomizers have resulted in the elimination of porosity from the internal bore of a sprayed tube. Bimetallic tubing can also be manufactured and the installation of a 4.5 ton tube plant in the USA should provide low operation costs. (iii) Spray forming offers a potentially low cost manufacturing route for superalloy ring/casing components in high strength superalloys. (iv) A large pilot plant has been built for the spray forming of ultra-clean superalloys for turbine disc applications. (v) Using twin-atomizing technology, special steel billets have been spray formed up to 400mm diameter with deposition yields in excess of 90%. (vi) Al/Si alloy extrusion billets with excellent dimensional tolerances are being manufactured for large scale automotive applications. Several new aluminum alloys have also been developed, including high strength, low density and low cocfficient of expansion materials. (vii) New copper alloys have been developed and pilot plants are in operation to produce these alloys once markets have become established.