Stainless Steel Intake Weirs at Makinokuchi Power
Plant
Applicant:Hitachi Zosen Corporation.
Reason for selection: “This is a pioneering case in which an approach has been taken to extend
the service life of a facility to generate hydroelectric power, a renewable
energy, with the use of durable, alloy-saving stainless steel. Changing
the material of the weirs to stainless steel from others ( rubber, carbon
steel) is expected to further advance movements toward a carbon-free society.
At Makinokuchi Power Plant, the flap gates with bags of rubber-reinforced
cloth (hereinafter “rubber weirs”) were so severely damaged with repeated
floods causing stones to flow down from upstream that their continued use
was rendered impractical. In light of such weakness, rubber weirs were
found inadequate for measures to absorb shocks caused by these flood-induced
flowing stones and to withstand frictional wears caused by mudslide.
This has led to the adoption of stainless steel for the flap gate and from among various grades, an alloy-saving stainless steel grade (SUS821L1) with excellent anti-abrasion property has been selected for longer service life of the weirs.
