About TAKAGI K
About Nippon Kokan Koji KK, Yokohama
About ARAKIDA F
About Nippon Kokan Koji KK, Yokohama
About SATO S
About Nippon Kokan Koji KK, Yokohama
About MIYAMORI H
About Nippon Kokan Koji KK, Yokohama
About OZAWA M
About Nippon Kokan Koji KK, Yokohama
About Metal Construction
About pipeline
About MIAB溶接
About Welding techniques
About 都市
About ガスパイプライン
About 磁気
About 推進
About アーク
About 突合せ
About 溶接