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EP0096078A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Method of measuring on-line hardness of steel plate

Assignee: JFE Steel Corp
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Filing: 1982-12-11
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Granted: —
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Expires: 2002-12-11
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Abstract

Abstract This method comprises the steps of positioning a steel plate (21) and a DC-energized electromagnet (22) facing each other so that they are moving relative to each other, separately providing both the positive and negative poles of the magnet (22) in the direction of the relative movement, magnetizing to saturation part of the steel plate (21) which has been magnetized to saturation by one pole of the electromagnet (22) in the reverse direction by the other pole of the electromagnet (22), measuring the intensity of the residual magnetism of the part magnetized to saturation by a detector (24), and obtaining the hardness of that part from the intensity of the measured residual magnetism.

Inventors

  • 👤 Mamoru Akiyama
  • 👤 Satoru Takahashi
  • 👤 Toshio Tamiya

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-04 15:53
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/72

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 139 words
Nethod of measuring on-line the hardness of a steel plate, wherein said steel plate (21) and an electromagnet (22)excited by a direct current are opposed to each other under a condition of being movable relative to each other, both positive and negative poles of said electromagnet (22) are spaced apart from each other in the direction of being movable relative to each other, a portion of said steel plate (21), which has been magnetically saturated by one of the magnetic poles of said electromagnet (22) is magnetically saturated in the reverse direction by the other of the magnetic poles of said electromagnet (22), and the strength of residual magnetism at said portion magnetically saturated is measured by a detector (24), whereby the hardness of said portion is sought on the basis of the strength of residual magnetism thus measured.
Claim 2
Dependent Claim 139 words
Nethod of measuring on-line the hardness of a steel plate, wherein said steel plate (21) and an electromagnet (22)excited by a direct current are opposed to each other under a condition of being movable relative to each other, both positive and negative poles of said electromagnet (22) are spaced apart from each other in the direction of being movable relative to each other, a portion of said steel plate (21), which has been magnetically saturated by one of the magnetic poles of said electromagnet (22) is magnetically saturated in the reverse direction by the other of the magnetic poles of said electromagnet (22), and the strength of residual magnetism at said portion magnetically saturated is measured by a detector (24), whereby the hardness of said portion is sought on the basis of the strength of residual magnetism thus measured.
Claim 3
Dependent Claim 36 words
Method of measuring on-line the hardness of a steel plate as set forth in clame 1, wherein both the electromagnet (22) and the detector (24) are opposed to conveying rollers (32) for the steel plate (21).
Claim 4
Dependent Claim 36 words
Method of measuring on-line the hardness of a steel plate as set forth in clame 1, wherein both the electromagnet (22) and the detector (24) are opposed to conveying rollers (32) for the steel plate (21).
Claim 5
Dependent Claim 40 words
Method of measuring on-line the hardness of a steel plate as set forth in claim 1 or 2, wherein both the electromagnet (22) and the detector (24) are made transversely movable in the widthwise direction of the steel plate (21).

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