Kawasaki Steel Corporation

Ichiro Samejima

Sachihiro Iida

Naoto Ueno

A seal roll apparatus and method hermetically seals boundaries between a plurality of heat-treating sections for continuously heating and cooling a strip material in a continuous heat-treatment furnace. The seal roll apparatus includes a seal roll room including at least a pair of water-cooled seal rolls opposed to each other with a gap therebetween for passing the strip material, and partitions having an opening for passing the strip material, a partition being provided at the inlet side and at the outlet side of the seal rolls.

Sealing apparatus in continuous heat-treatment furnace and sealing method

A continuous heat treatment furnace having one of a plurality of furnace zones except for first and last zones as a rapid cooling zone,for rapidly cooling a material by blowing an atmospheric gas, which comprises a roll-sealed chamber,partitioned at the inlet by first and second roll sealing devices,A and,B from the upstream and a third roll sealing device,C at the outlet as sealing means for atmospheric gas, and in which the inlet of the first roll sealing device and the outlet of the third roll sealing device are connected, and/or the roll-sealed chamber and an uppermost stream portion,in the rapid cooling zone are connected, and in which the hydrogen concentration in the furnace is controlled to 10% or higher in the rapid cooling zone and is controlled to 10% or lower in the furnace zone at the inlet of the rapid cooling zone. A continuous heat treatment furnace capable of simply preventing mixing of atmospheric gases in the rapid cooling zone and the atmospheric gas in the zone (heating zone, cooling zone or the like) adjacent with the rapid cooling zone of a gas jet cooling system, and a method of controlling the atmospheric gas in the furnace capable of preventing nitridation are provided.

Growing community of inventors

Chiyoda, Japan

Ichiro Samejima