The Chugoku Electric Power Co., Inc.

Hidetaka Nishida

Nobuaki Kosako

Hiroshi Yamaguchi

Hideo Matsumura

Tatsuya Kenzume

Daisuke Arakawa

An aspect of the present disclosure is to precisely define a constant value used in the Monkman-Grant analysis, when estimating remaining life of a high-chromium steel pipe through which high-temperature and high-pressure fluid is allowed to flow. A remaining life estimation method according to the present disclosure is particularly characterized in that a step of obtaining a constant on an accelerated creep test is performed in which a constant indicative of the product of a strain rate and a rupture time in the Monkman-Grant analysis is obtained by multiplying a first coefficient to transform uniaxial rupture ductility into multiaxial rupture ductility, the uniaxial rupture ductility being obtained from a specimen of the high-chromium steel pipe, a second coefficient to amend consumed life of the specimen, and a third coefficient to amend a measured pressure into an assessment pressure.

Remaining life estimation method for estimating remaining life of high-chromium steel pipe

A method of predicting growth of a crack in a member includes memorizing, for each portion on the member, stress distribution &#x394;&#x3c3;(a) in the depth direction obtained in the case that no crack is present, a relationship between depth of growing cracks and creep contribution, and a relationship between creep contribution and parameters C and m of the Paris's law, receiving from a user an indication of a certain portion on the member, acquiring the stress distribution &#x394;&#x3c3;(a) in the depth direction for the certain portion, acquiring a creep contribution at the depth of a growing crack for the certain portion, from the relationship between depth of cracks and creep contribution memorized for the certain portion, and acquiring parameters C and m corresponding to the acquired creep contribution, from the relationship between creep contribution and parameters C and m of the Paris's law memorized for the certain portion.

Method of predicting crack growth and information processing device therefor

A distance measuring apparatus includes a reference member that is installed on a surface of a first metal member; a range finder that measures a distance to the reference member; and a mounting member to which the range finder is placed. The mounting member is installed on a surface of a second metal member coupled to the first metal member via a weld. One of the mounting member and the range finder includes first and second protruding parts. The other thereof includes first and second fitting holes into which the first and the second protruding parts are fit, respectively, such that the range finder is mounted to the mounting member, and first and second pressing members that press the first and second protruding parts from first and second directions toward inner side surfaces of the first and second fitting holes, respectively.

Distance measuring apparatus and distance measuring method

A repair method for repairing a crack generated to a cast steel member due to a thermal stress includes removing a part of the cast steel member including the crack at a surface of the cast steel member to form a recess, fitting into the recess a first repair member that is made of a metal that is more flexible than the cast steel member and that is weldable to the cast steel member, and spot welding the first repair member to the cast steel member.

Repair method for cast steel member

A remaining service life evaluation method for evaluating a remaining service life of a metal pipe suffering from creep damage on a basis of a master curve that is prepared in advance that includes wrapping a steel strip around an outer peripheral face of the metal pipe under same conditions as those during an internal pressure creep test and evaluating a remaining service life of the metal pipe on a basis of a degree of deterioration of the steel strip.

Remaining service life evaluation method for metal pipe suffering from creep damage

A pipe-reinforcing implement with excellent workability during attachment to the piping is provided. The reinforcing implementis to be arranged along an outer circumferential face Xb of a metal piping X, in a state surrounding the piping in a circumferential direction, in which creep may occur due to a high temperature and pressure fluid inside, and configured to reinforce creep strength of the piping, the reinforcing implement including a plurality of reinforcing membersarranged in the circumferential direction to be joined and a plurality of laminate membersoverlaid in a radial direction of the piping to configure each of the reinforcing members.

Pipe-reinforcing implement

A distance measuring system includes: a reference member configured to be provided on a surface of a first pipe made of metal, the reference member serving as a reference for distance measurement; an attachment member provided on a surface of a second pipe, made of metal, connected with the first pipe through a weld; a distance sensor configured to be attached to the attachment member, to measure a distance to the reference member; and a measuring unit configured to measure the distance based on an output from the distance sensor.

Distance measurement system and distance measurement method

A part where a creep void is recognized is observed at an arbitrary magnification by a scanning electron microscope, an optical microscope, and a laser microscope, and the maximum value of creep void crystal grain boundary occupancy is measured in the field of view. The maximum value is applied to a a master curve corrected from the results of a test of simulating an actual machine and a test piece of actual machine size, taking account of internal damage of the machine. Thus the creep lifetime consumption rate of a member is estimated easily with high accuracy.

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Hiroshima, Japan

Hidetaka Nishida