Nuclear Industrial Directory of Japan

Nuclear Industrial Directory of Japan



1-14, Nakamachi, Moji-ku, Kitakyushu City, Fukuoka 800-8601, Japan

Contact Person
International Sales Section, Sales Dept. Sales Headquarters

Corporate Information

Established in 1926, OKANO VALVE MFG. CO. LTD. has been on the front line in development and design of some of the world’s most important valves. With the expansion of thermal and nuclear power plants in and outside of Japan, these valves help provide the base for our current technology. OKANO manufactures most types of valves used for thermal and nuclear power plants, as well as other fields of industry. Covering ultralow to ultrahigh temperatures as well as vacuum area to high pressure, these valves total more than one million.

Main Activities

1. Design

2. Manufacturing (Valves and Materials)

3. Material Supply

4. Maintenance

5. Quality Assurance Program

Products & Technologies

Material Organization

Having our steel casting shop, we manufacture quality casting material including valve parts for manufacturing proved by lots of data accumulated.


OKANO is the world’s first valve manufacturer to produce valves with seat surfaces overlaid with stellite alloy. This technology has been adopted worldwide as the standard in valve manufacturing.

Main Steam Safety Relief Valves

OKANO’s design and development of the Main Steam Safety Relief Valve(MS-SRV) is one of the most important valves to assure safety of BWR and ABWR nuclear power plants. Proving our technology is capable of responding to future development, the MS-SRV has been adopted by all BWR nuclear plants throughout Japan. In addition, having obtained the ASME NV Certificate, the MS-SRV manufactured by OKANO is ready to be adopted worldwide.