Patents by Inventor Kota Tomatsu

Kota Tomatsu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20150047749
    Abstract: A low alloy steel subjected to post weld heat treatment, containing, by mass percent, of C: 0.01 to 0.15%, Si: 3% or less, Mn: 3% or less, and Al: 0.08% or less, one or more kinds of elements selected from Ti, V and Nb: the range satisfying Formula (1), and the balance being Fe and impurities, wherein in the impurities, N: 0.01% or less, P: 0.05% or less, S: 0.03% or less, and O: 0.03% or less: 0.1×[C(%)]?[Ti(%)]+[V(%)]+0.5×[Nb(%)]?0.2??(1) where, the symbol of element in the formula represents the content (mass %) of each element. In the alloy steel, a HAZ subjected to PWHT, especially short-time PWHT, has excellent hydrogen embrittlement resistance in wet hydrogen sulfide environments or the like.
    Type: Application
    Filed: December 17, 2012
    Publication date: February 19, 2015
    Inventors: Hiroyuki Hirata, Tomohiko Omura, Kenji Kobayashi, Kaori Kawano, Kota Tomatsu, Kazuhiro Ogawa
  • Publication number: 20140348695
    Abstract: A low alloy steel, containing, by mass percent, C: 0.01 to 0.15%, Si: 3% or less, Mn: 3% or less, B: 0.005 to 0.050%, and Al: 0.08% or less, and the balance being Fe and impurities, wherein in the impurities, N: 0.01% or less, P: 0.05% or less, S: 0.03% or less, and O: 0.03% or less. In the alloy steel, a HAZ has excellent resistance to embrittlement attributable to hydrogen such as stress corrosion cracking in wet hydrogen sulfide environments.
    Type: Application
    Filed: December 17, 2012
    Publication date: November 27, 2014
    Inventors: Hiroyuki Hirata, Kenji Kobayashi, Tomohiko Omura, Kaori Kawano, Kota Tomatsu, Kazuhiro Ogawa