Inorganic zinc shop primer의 鎔接性 向上을 위한 硏究

Abstract

Shop primer is applied immediately to the blast-cleaned steel surface after removing every foreign matter of mill scale, rust, and so on. It is for temporary protection against corrosion during fabrication, transport, installation and storage of large constructions such as ship buildings, bridges, off-shore structures, oil storage tanks, and so on. Since the late 1970’s, current inorganic zinc rich primer that has excellent welding, gas-cutting, anti-corrosion properties is using most plentifully in large constructions of new shipbuilding etc. Recently, it is needed the stability of welding property to improve the long-term a durability of the constructions in high speed and high temperature as well as the anti-corrosive property that has been demanded. To minimize a welding defects of inorganic zinc rich shop primer, we investigated compositions of shop primer, such as the content of organic and inorganic binder, zinc dust, additive, catalyst and type of extender, solvent, As a result, when the content of zinc dust is low, the number of welding defects decreased. But we have to keep the content of zinc dust at least 70% in solid for the anti-corrosion property in fabrication period. The extender pigment having no water of crystallization and heat-resisting property resulted in good weldability. As the content of organic binder in compositions of shop primer increases, the number of welding defects on the surface of welded steel was increased. As the thickness of shop primer coating increases, the defects in welding part were increased The solvent composition of the base should be considered for application propriety at shop line.