Sumitomo Metal Industries, Inc.

Toshihiko Sakai

Tatsuo Hiroshima

Sumio Kobayashi

Takao Suzuki

Yoshiyasu Sakamoto

Tetuo Asano

Yuji Narita

This invention relates to a repairing apparatus for an industrial furnace wall using a plasma spray gun. The plasma flame of the gun traces the damaged part to be repaired by moving the gun in three-dimensional directions (up-and downwardly, right-and leftwardly, and forwardly and backwardly) relative to the furnace wall to be repaired. Furthermore, the optimum spray distance of the plasma flame follows the unevenness of the furnace wall and the depression extent of a damaged part to be repaired from the sound surface of a furnace wall by changing the mixture ratio of the operation gas for the gun to control the length of the plasma flame.

Repairing apparatus for furnace wall

In repairing a blast furnace wall by injecting and solidifying a refractory material on the inside wall of the furnace from outside the furnace, a line consisting of metallic coaxial lines or metallic parallel lines insulated from each other is embedded in the refractory material and the variation of the length of this line is measured through an electric signal to detect the remaining thickness of the injected and solidified refractory material in the furnace wall part. By such detection, the damage of the repaired part of the blast furnace can be known with the lapse of time.

Method and apparatus for detecting damage of blast furnace inside wall

In a high-temperature furnace such as a heating furnace, a melting furnace or a blast furnace, a cooling cell assembly of a ferromagnetic material such as iron is used in the furnace wall. The thickness of the cooling cell assembly can be detected by winding primary and secondary windings about an iron core, passing an alternating current through the primary winding and inserting a sensor in an inspection hole for detecting the current or voltage induced in the secondary winding, forming a magnetic circuit in the sensor and a portion of the furnace wall, and detecting variations in magnetic permeability between the cooling cell assembly and mortar, refractory bricks or air gaps.

Growing community of inventors

Amagasaki, Japan

Toshihiko Sakai