Corporate Profile

Corporate ProfileSUPERO


  • Nov., 1926
    OKANO VALVE MFG.CO. was found by Mr. Mitsuru Okano, with the view of meeting the demands for Steel Valves required mainly by Japanese Thermal Power Plants in the field of High Pressure and High Temperature Services.
  • Mar., 1935
    Production Works was established at the present location, and the Head Office and factory facilities were relocated. 

    At the same time, facilities were modernized and an integrated manufacturing system "from Steel Castings to Completed Products" was established.

    Succeeded in manufacturing high pressure and high temperature service in Japan for thermal power plants.
  • Jul., 1942
    Yukuhashi Steel Foundry was established.

    During the war, the company devoted its efforts exclusively to the manufacture of valves in accordance with the military, naval, and industrial requirements, and met the rapidly increasing demands with high quality steel valves
  • 1950-1959
    Remodernized the facilities in Production Works and Yukuhashi Steel Foundry, and reorganized the former to specialize in machining and assembling, and the latter in mass production of steel castings.

    Commenced manufacture of large-sized high quality marine valves in addition to high pressure and high temperature service valves for thermal power plants and petro-chemical industries.

    Special research and development division, consisting of the staff of technical experts and testing specialists, was organized intending to study and develop the special valves for nuclear reactors, sodium loops, nuclear test equipments, etc.

    Undertook the long-term modernization program and put the rationalization of facilities and manufacturing system into practice.
  • 1960-1969
    Equipped Yukuhashi Steel Foundry with an 8-ton Electric Arc Furnace for mass production, and modernized the facilities.

    In parallel with the commencement of manufacturing special valves for nuclear service, reorganized Production Works and Yukuhashi Steel Foundry, and established a complete quality control and assurance system. Also installed the facilities for complete radiographic testings and the facilities for the Technical Research Laboratory.
  • 1970-1979
    Large-Sized Valve Machining, Assembling, and Testing Factory was established in the site of Yukuhashi Steel Foundry to meet the demands of large-sized valves including nuclear service valves. Also renovated the facilities to process large-size valves.

    Equipped the Head Office with an electronic computer EDPS-SUPERO MICS for rationalization

    Manufactured and supplied the first Main Steam Safety/ Relief Valves to the Nuclear Power Plants (BWR).

    Established the After-Service Department in order to meet the increasing demands for maintenance service of nuclear power plants.

    Manufactured and supplied the first safety valves for super critical services of thermal power plants.

    Obtained ASME Certificates "N", "NPT", "NV", and "Materials" for nuclear service.
  • 1980-1989
    Performed "Seismic and Moment Transfer Qualification Test" and "Full Flow Engineering Qualification Test" of the Main Steam Safety / Relief Valve at Wyle Laboratory in Alabama, U.S.A., then, the "Durability Qualification Test" by the steam test facilities at Okano Valve and the durability was confirmed in all respects.

    Obtained ASME Certificates "V" & "UV" for power boiler and pressure vessel safety valves

     Equipped the Computer Aided Design System (CAD) for speed-up, accuracy, and cost-down of designing.

    Performed the Operability Tests, Seismic Tests, Environment Tests, and Pipe Reaction Load Test & Stress Measurement of general valves and safety/relief valves (BWR) for nuclear service at the Nuclear Power Engineering Test Center in Japan.
  • 1990-1999
    Obtained Quality System Certificate ISO 9001 for design and manufacture of Cast & Forged Steel Valves and Steel Castings.

    Develop and supply Supper Corrosion Proof Lining Valve. Expand ISO 9001 added maintenance. Develop small size Globe Valve with easy handling operation. Obtained environment Certificate ISO 14001.
  • 2000-2009
    Reconstruction and trial Seat replacement device at site.
    Develop Space measurement device for stem-bush Motor-ope. Valve.
    Develop Visual control system under high radioactive valve.
    Develop ETFE Lining Butterfly Valve.
    Obtained certifications for delivery of valves to nuclear power plants in China.
  • 2010-
    Obtained the nuclear code certification (N, NV, NPT) provided by the American Society of Mechanical Engineers (ASME). 
    Masatoshi Okano became chairperson and representative director and Masaki Okano became president and representative director.