Local dry underwater welding is one of the key technologies for on site construction and maintenance of very large offshore floating structures(Mega-Float). Mechanical properties for wet welding is relatively poor compared to dry welding because of bad influence by surrounding water at the welding part. Local dry welding procedure by using of water curtain shield is one solution to improve mechanical properties. This technique is so simple to reduce much cost and working time, if complete dry condition is guaranteed during welding operation. This paper describes a way to visualize two-dimensional wet condition using an infrared video camera with an optical bandpass filter for automatic detection of water on a plate to be welded. The water has absorption spectra in the infrared region at wave lengths 1450 nm and 1940 nm. An IR sensitive video camera (from 500 to 2000 nm) combined with an optical bandpass filter (1450 nm) was used to visualize the wet condition on steel plate. Wet region was recognized automatically by image processing.


    Access

    Access via TIB

    Check availability in my library


    Export, share and cite



    Title :

    Detection of wet condition for underwater local dry welding


    Contributors:
    Ogawa, Y. (author)


    Publication date :

    1998


    Size :

    4 Seiten, 3 Quellen


    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    Underwater welding

    Tema Archive | 1976


    Welding underwater

    Davis, L. | Tema Archive | 1984


    Underwater MIG welding

    Hamasaki, M. / Sakakibara, J. / Arata, Y. | Tema Archive | 1976


    Underwater friction welding

    Tema Archive | 1975


    Fusion welding underwater

    Tema Archive | 1975