Yasugi Specialty Steel and Tatara
Yoshisuke Ayukawa and the New Wako (Japanese Steel)
The Japanese economy sank into a deep depression following the conclusion of
World War I. Unpaku Steel, which now changed its name to Yasugi Steelworks,
Co., eventually closed part of its factory in 1920 and Kisaku Ibe, who had
been responsible for both administration and engineering at the company up
to this point, resigned as president. In 1925, seeking to rebuild the factory,
the company asked Yoshisuke Ayukawa of the Kyoritsu Corporation for his assistance,
entrusting management of Yasugi Steelworks to his company. Ayukawa would later
become a major entrepreneur, founding Nissan Konzern (Nissan Motors) and during
World War II establishing the Manchuria Heavy Industry Co. When he came to
look over the Yasugi operation, he apparently was impressed by the technology
of the tatara and took it upon himself to be its savior, saying that “the shining
light of Japanese steel must not be allowed to go out.” He made it a policy
that “the emphasis is to be placed on quality more than on quantity,” the basic
philosophy that guides Hitachi Metals today.
Assigned to be the actual leader of operations at Yasugi Steelworks under President
Ayukawa was Professor Haruto Kudo. Seeking to use wako as would best suit the
times, Kudo in 1931 started to produce two types of what might be called “the
new Japanese steel” at the newly built Kisuki Factory (located in the middle
of the Hi'i River basin). These types of steel were called seijo (“pure”) particle
iron and kaimen (“sponge”) iron.
Seijo particle iron is made by smelting charcoal pig iron manufactured in
a square furnace in an electric furnace and then putting it into a stream of
water. It is used as source iron of a particle shape. Kaimen iron is made by
putting charcoal and iron sand into a kind of rotary kiln called a tokamiro,
reducing it at low heat, and producing iron that is spongelike in shape.
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| Tokamiro (Wako Museum) |
