Critical hardness for HSC in deposit welding on steel line pipes under cathodic protection

Noritake Oguchi, Hiroyuki Lnoue, Junichi Sakai, Shigeru Komukai

    研究成果: Conference contribution

    1 引用 (Scopus)

    抄録

    Repairing corrosion-damaged areas of operational steel line pipes by deposit welding performed without stopping the gas flowing inside is a common practice. However, this repair method tends to considerably increase the hardness of the weld metal and the HAZ, and it poses the risk of HSC under cathodic protection. In this study, the HSC susceptibility of the welding area was examined using welded full-scale C-ring specimens. The specimens were prepared from X42, X60, and X65 steel line pipes, whose outer diameter and longitudinal length were 610mm and 100 to 110mm, respectively, and whose nominal thickness was 10.3 to 15.1mm. Deposit welding was applied to the middle of each specimen's outer surface, and then a bolt through the specimen was tightened until the welded part was subjected to yield stress. The welded surface of the welding and its surrounding area were exposed to a test solution whose pH was adjusted to 7, and a cathodic current of 20mA/cm2 or 4mA/cm 2 was applied for 500hours. Cracks appeared in the weld metals on the C-ring specimens to which a cathodic current of 20mA/cm2 had been applied. However, the propagation of the cracks ceased at the boundaries between the weld metal and the HAZ, and no cracks initiated in the HAZ. The maximum hardness of the HAZ was about 300 to 400Hv. These levels of hardness are far greater than 260Hv, which is the value obtained from experiments carried out using slow strain rate testing and is widely used in Japan as a criterion of hardness for avoiding HSC in the HAZ.

    元の言語English
    ホスト出版物のタイトルProceedings of the Biennial International Pipeline Conference, IPC
    ページ371-376
    ページ数6
    2
    DOI
    出版物ステータスPublished - 2007
    イベント2006 6th International Pipeline Conference, IPC 2006 - Calgary, AB
    継続期間: 2006 9 252006 9 29

    Other

    Other2006 6th International Pipeline Conference, IPC 2006
    Calgary, AB
    期間06/9/2506/9/29

    Fingerprint

    Cathodic protection
    Welding
    Deposits
    Hardness
    Pipe
    Welds
    Steel
    Heat affected zone
    Cracks
    Metals
    Bolts
    Yield stress
    Strain rate
    Repair
    Corrosion
    Testing
    Gases
    Experiments

    ASJC Scopus subject areas

    • Engineering(all)

    これを引用

    Oguchi, N., Lnoue, H., Sakai, J., & Komukai, S. (2007). Critical hardness for HSC in deposit welding on steel line pipes under cathodic protection. : Proceedings of the Biennial International Pipeline Conference, IPC (巻 2, pp. 371-376) https://doi.org/10.1115/IPC2006-10227

    Critical hardness for HSC in deposit welding on steel line pipes under cathodic protection. / Oguchi, Noritake; Lnoue, Hiroyuki; Sakai, Junichi; Komukai, Shigeru.

    Proceedings of the Biennial International Pipeline Conference, IPC. 巻 2 2007. p. 371-376.

    研究成果: Conference contribution

    Oguchi, N, Lnoue, H, Sakai, J & Komukai, S 2007, Critical hardness for HSC in deposit welding on steel line pipes under cathodic protection. : Proceedings of the Biennial International Pipeline Conference, IPC. 巻. 2, pp. 371-376, 2006 6th International Pipeline Conference, IPC 2006, Calgary, AB, 06/9/25. https://doi.org/10.1115/IPC2006-10227
    Oguchi N, Lnoue H, Sakai J, Komukai S. Critical hardness for HSC in deposit welding on steel line pipes under cathodic protection. : Proceedings of the Biennial International Pipeline Conference, IPC. 巻 2. 2007. p. 371-376 https://doi.org/10.1115/IPC2006-10227
    Oguchi, Noritake ; Lnoue, Hiroyuki ; Sakai, Junichi ; Komukai, Shigeru. / Critical hardness for HSC in deposit welding on steel line pipes under cathodic protection. Proceedings of the Biennial International Pipeline Conference, IPC. 巻 2 2007. pp. 371-376
    @inproceedings{8ec6b74c47934c73824d270d30033ce0,
    title = "Critical hardness for HSC in deposit welding on steel line pipes under cathodic protection",
    abstract = "Repairing corrosion-damaged areas of operational steel line pipes by deposit welding performed without stopping the gas flowing inside is a common practice. However, this repair method tends to considerably increase the hardness of the weld metal and the HAZ, and it poses the risk of HSC under cathodic protection. In this study, the HSC susceptibility of the welding area was examined using welded full-scale C-ring specimens. The specimens were prepared from X42, X60, and X65 steel line pipes, whose outer diameter and longitudinal length were 610mm and 100 to 110mm, respectively, and whose nominal thickness was 10.3 to 15.1mm. Deposit welding was applied to the middle of each specimen's outer surface, and then a bolt through the specimen was tightened until the welded part was subjected to yield stress. The welded surface of the welding and its surrounding area were exposed to a test solution whose pH was adjusted to 7, and a cathodic current of 20mA/cm2 or 4mA/cm 2 was applied for 500hours. Cracks appeared in the weld metals on the C-ring specimens to which a cathodic current of 20mA/cm2 had been applied. However, the propagation of the cracks ceased at the boundaries between the weld metal and the HAZ, and no cracks initiated in the HAZ. The maximum hardness of the HAZ was about 300 to 400Hv. These levels of hardness are far greater than 260Hv, which is the value obtained from experiments carried out using slow strain rate testing and is widely used in Japan as a criterion of hardness for avoiding HSC in the HAZ.",
    author = "Noritake Oguchi and Hiroyuki Lnoue and Junichi Sakai and Shigeru Komukai",
    year = "2007",
    doi = "10.1115/IPC2006-10227",
    language = "English",
    volume = "2",
    pages = "371--376",
    booktitle = "Proceedings of the Biennial International Pipeline Conference, IPC",

    }

    TY - GEN

    T1 - Critical hardness for HSC in deposit welding on steel line pipes under cathodic protection

    AU - Oguchi, Noritake

    AU - Lnoue, Hiroyuki

    AU - Sakai, Junichi

    AU - Komukai, Shigeru

    PY - 2007

    Y1 - 2007

    N2 - Repairing corrosion-damaged areas of operational steel line pipes by deposit welding performed without stopping the gas flowing inside is a common practice. However, this repair method tends to considerably increase the hardness of the weld metal and the HAZ, and it poses the risk of HSC under cathodic protection. In this study, the HSC susceptibility of the welding area was examined using welded full-scale C-ring specimens. The specimens were prepared from X42, X60, and X65 steel line pipes, whose outer diameter and longitudinal length were 610mm and 100 to 110mm, respectively, and whose nominal thickness was 10.3 to 15.1mm. Deposit welding was applied to the middle of each specimen's outer surface, and then a bolt through the specimen was tightened until the welded part was subjected to yield stress. The welded surface of the welding and its surrounding area were exposed to a test solution whose pH was adjusted to 7, and a cathodic current of 20mA/cm2 or 4mA/cm 2 was applied for 500hours. Cracks appeared in the weld metals on the C-ring specimens to which a cathodic current of 20mA/cm2 had been applied. However, the propagation of the cracks ceased at the boundaries between the weld metal and the HAZ, and no cracks initiated in the HAZ. The maximum hardness of the HAZ was about 300 to 400Hv. These levels of hardness are far greater than 260Hv, which is the value obtained from experiments carried out using slow strain rate testing and is widely used in Japan as a criterion of hardness for avoiding HSC in the HAZ.

    AB - Repairing corrosion-damaged areas of operational steel line pipes by deposit welding performed without stopping the gas flowing inside is a common practice. However, this repair method tends to considerably increase the hardness of the weld metal and the HAZ, and it poses the risk of HSC under cathodic protection. In this study, the HSC susceptibility of the welding area was examined using welded full-scale C-ring specimens. The specimens were prepared from X42, X60, and X65 steel line pipes, whose outer diameter and longitudinal length were 610mm and 100 to 110mm, respectively, and whose nominal thickness was 10.3 to 15.1mm. Deposit welding was applied to the middle of each specimen's outer surface, and then a bolt through the specimen was tightened until the welded part was subjected to yield stress. The welded surface of the welding and its surrounding area were exposed to a test solution whose pH was adjusted to 7, and a cathodic current of 20mA/cm2 or 4mA/cm 2 was applied for 500hours. Cracks appeared in the weld metals on the C-ring specimens to which a cathodic current of 20mA/cm2 had been applied. However, the propagation of the cracks ceased at the boundaries between the weld metal and the HAZ, and no cracks initiated in the HAZ. The maximum hardness of the HAZ was about 300 to 400Hv. These levels of hardness are far greater than 260Hv, which is the value obtained from experiments carried out using slow strain rate testing and is widely used in Japan as a criterion of hardness for avoiding HSC in the HAZ.

    UR - http://www.scopus.com/inward/record.url?scp=34547547737&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=34547547737&partnerID=8YFLogxK

    U2 - 10.1115/IPC2006-10227

    DO - 10.1115/IPC2006-10227

    M3 - Conference contribution

    AN - SCOPUS:34547547737

    VL - 2

    SP - 371

    EP - 376

    BT - Proceedings of the Biennial International Pipeline Conference, IPC

    ER -