Method and apparatus for predicting deterioration of a member constituting a part of equipment

Claim 1

A method for predicting the degree of deterioration of a metal member in a machine or apparatus with the aid of a computer, said metal member having a ferromagnetic phase, comprising: (a) a step of storing in a memory data indicating a relation between a physical property of said member to be measured and the degree of deterioration of said member; (b) a step of measuring said physical property of said member by sensor means at a plurality of locations within one region of said member; (c) a step of converting said physical property into electrical signals; (d) a step of inputting said electrical signals to said computer; (e) a step of determining by said computer the extreme value of said measured values obtained in said one region; (f) a step of carrying out said steps (b), (c), (d) and (e) in a plurality of regions of said member, respectively, to thereby determine the extreme values for said plurality of regions, respectively, by means of said computer; (g) a step of estimating an extreme value of said physical property for said member as a whole on the basis of said extreme values for said plurality of regions by applying a return period defined according to extreme value statistical theory; (h) a step of predicting the degree of deterioration of aid member on the basis of data stored in said memory and said estimated extreme value determined at said step (g); and (i) a step of recognizing results obtained by said computer in said steps (e), (f) and (g), and graphically displaying them on a display device.

Claim 2

A method for predicting the degree of deterioration of a metal member in a machine or apparatus with the aid of a computer, said metal member having a ferromagnetic phase, comprising: (a) a step of storing in a memory data indicating a relation between a physical property of said member to be measured and the degree of deterioration of said member; (b) a step of measuring said physical property of said member by sensor means at a plurality of locations within one region of said member; (c) a step of converting said physical property into electrical signals; (d) a step of inputting said electrical signals to said computer; (e) a step of determining by said computer the extreme value of said measured values obtained in said one region; (f) a step of carrying out said steps (b), (c), (d) and (e) in a plurality of regions of said member, respectively, to thereby determine the extreme values for said plurality of regions, respectively, by means of said computer; (g) a step of estimating an extreme value of said physical property for said member as a whole on the basis of said extreme values for said plurality of regions by applying a return period defined according to extreme value statistical theory; (h) a step of predicting the degree of deterioration of aid member on the basis of data stored in said memory and said estimated extreme value determined at said step (g); and (i) a step of recognizing results obtained by said computer in said steps (e), (f) and (g), and graphically displaying them on a display device.

Claim 8

An apparatus for predicting the degree of deterioration of a metal member in a machine or apparatus, said metal member having a ferromagnetic phase, comprising: sensor means for measuring a magnetic property of said member, and converting the measured property into electrical signals; memory means for storing data indicating said magnetic property of said member to be measured and the degree of deterioration of said member; means connected to said sensor means for measuring said magnetic property in a plurality of regions of said member and for determining an extreme value of said measurements performed at a plurality of locations in each of said regions; means for estimating the extreme value of said magnetic property of said member as a whole on the basis of the extreme values in said regions, respectively, by applying a return period defined according to extreme value statistical theory; means for predicting the degree of deterioration of said member on the basis of the extreme value of said magnetic property of said member as a whole; and means for recognizing the extreme value or the degree of deterioration of said member, and displaying it graphically.

Claim 9

An apparatus for predicting the degree of deterioration of a metal member in a machine or apparatus, said metal member having a ferromagnetic phase, comprising: sensor means for measuring a magnetic property of said member, and converting the measured property into electrical signals; memory means for storing data indicating said magnetic property of said member to be measured and the degree of deterioration of said member; means connected to said sensor means for measuring said magnetic property in a plurality of regions of said member and for determining an extreme value of said measurements performed at a plurality of locations in each of said regions; means for estimating the extreme value of said magnetic property of said member as a whole on the basis of the extreme values in said regions, respectively, by applying a return period defined according to extreme value statistical theory; means for predicting the degree of deterioration of said member on the basis of the extreme value of said magnetic property of said member as a whole; and means for recognizing the extreme value or the degree of deterioration of said member, and displaying it graphically.

Claim 14

An apparatus for predicting the degree of deterioration of a member in a machine or apparatus installed in a plant, said member having a ferromagnetic phase, comprising: sampling means for sampling portions of said member as specimens at different regions of said member, wherein a plurality of specimens are obtained in each of said regions; sensor means for measuring a metallographic property of said member, and converting the property into electrical signals; memory means for storing data indicating a relation between said metallographic property of said member to be inspected and the degree of deterioration of said member; means connected to said sensor means for measuring said metallographic property of said plural specimens sampled from each of a plurality of regions on said member by means of said sensor means and determining an extreme value of those resulting from measurements of the plural specimens sampled for each of said regions; means for estimating the extreme value of said metallographic property for said member as a whole on the basis of the extreme values determined for said regions, respectively, by applying the return period defined according to extreme value statistical theory; means for predicting the degree of deterioration of said member on the basis of the extreme value of said metallographic property estimated for said member as a whole by referencing the data stored in said memory means; and means for recognizing the extreme value or the degree of deterioration of said member, and displaying it graphically.

Claim 15

An apparatus for predicting the degree of deterioration of a member in a machine or apparatus installed in a plant, said member having a ferromagnetic phase, comprising: sampling means for sampling portions of said member as specimens at different regions of said member, wherein a plurality of specimens are obtained in each of said regions; sensor means for measuring a metallographic property of said member, and converting the property into electrical signals; memory means for storing data indicating a relation between said metallographic property of said member to be inspected and the degree of deterioration of said member; means connected to said sensor means for measuring said metallographic property of said plural specimens sampled from each of a plurality of regions on said member by means of said sensor means and determining an extreme value of those resulting from measurements of the plural specimens sampled for each of said regions; means for estimating the extreme value of said metallographic property for said member as a whole on the basis of the extreme values determined for said regions, respectively, by applying the return period defined according to extreme value statistical theory; means for predicting the degree of deterioration of said member on the basis of the extreme value of said metallographic property estimated for said member as a whole by referencing the data stored in said memory means; and means for recognizing the extreme value or the degree of deterioration of said member, and displaying it graphically.