A Conservation and Material Study of the Fire-fighting Nozzle Culture Heritage

Fire-fighting culture heritage refer to tangible items and materials that contain stories related to fire-fighting. Among the fire-fighting items, the nozzles, which play a large part in extinguishing fires, are of great conservation value because few of them are left as culture heritage. In this study, conservation treatment was performed while observing the surface and corrosion state of two nozzle culture heritage used for fire-fighting. The processes were recorded by reflectance transformation imaging technique. In addition, the material characteristics were examined through observation of surface microstructure and component analysis of a total of 3 samples, including 2 of these relics and 1 of recently produced nozzle. As a result, it was confirmed that most of the rust on the nozzle surface was atacamite, and that nantokite remained partially. The base metal of the nozzle was presumed to be red brass among the types of brass, considering that it contains Cu as the main element, 2 to 15% of Zn, 5% or less of Sn, and 8% or less of Pb as additional alloying elements. In addition, the crystal segregation did not disappear and the solid solution was generated as a heterogeneous dendrite, indicating that the brass casting used as a fire nozzle was rapidly cooled.