An occluded hydrogen content estimation method implemented by an occluded hydrogen content estimation device performs an occluded hydrogen content estimation step in which, based on an occluded hydrogen unit content which is a content of hydrogen occluded in a metal due to a change in humidity from a wet state to a dry state, a period after the metal is placed, and meteorological data corresponding to the period for an area where the metal is located, a content of occluded hydrogen that is absorbed in the metal for the period after the metal is placed is estimated. In the occluded hydrogen content estimation step, the occluded hydrogen content is estimated by multiplying the number of rainfalls in the meteorological data by the occluded hydrogen unit content.

An occluded hydrogen content estimation method implemented by an occluded hydrogen content estimation device performs an occluded hydrogen content estimation step in which, based on an occluded hydrogen unit content which is a content of hydrogen occluded in a metal due to a change in humidity from a wet state to a dry state, a period after the metal is placed, and meteorological data corresponding to the period for an area where the metal is located, a content of occluded hydrogen that is absorbed in the metal for the period after the metal is placed is estimated. In the occluded hydrogen content estimation step, the occluded hydrogen content is estimated by multiplying the number of rainfalls in the meteorological data by the occluded hydrogen unit content.

A hydrogen permeability testing device can measure hydrogen amount(s) entering a metal material by electrochemical hydrogen permeation. The device may include: a metal specimen having a hydrogen entry face through which hydrogen enters, a hydrogen detection face on which the entered hydrogen is detected, and a metal plating formed on the hydrogen detection face to detect the entered hydrogen; a reference and counter electrode for making an electrochemical reaction progress; an electrolytic vessel provided on a hydrogen detection face side, housing the reference and counter electrode, and containing an aqueous sodium silicate solution having a freezing point of ≤0° C. and capable of suppressing residual current to ≤10 nA/cm.sup.2 when an electric potential of the hydrogen detection face is −1 to 1 V relative to the reference electrode; and a measurement unit which measures the amount of hydrogen based on a current value resulting from the electrochemical reaction.

A decarburization end point determination method includes: estimating the carbon concentration and oxygen concentration of the molten steel and carbon dioxide gas concentration of exhaust gas in the vacuum chamber by using measurement values of the carbon concentration and the oxygen concentration of the molten steel, a measurement value of internal pressure of the vacuum chamber, and a model formula; correcting a parameter included in the model formula to reduce at least one of a difference between an estimate value and a measurement value of the oxygen concentration and a difference between an estimate value and a measurement value of the carbon dioxide gas concentration of the exhaust gas; estimating the carbon concentration of the molten steel by using the model formula in which the parameter is corrected; and determining timing when an estimate value reaches a target value as the completion time point of the vacuum decarburization treatment.

A decarburization end point determination method includes: estimating the carbon concentration and oxygen concentration of the molten steel and carbon dioxide gas concentration of exhaust gas in the vacuum chamber by using measurement values of the carbon concentration and the oxygen concentration of the molten steel, a measurement value of internal pressure of the vacuum chamber, and a model formula; correcting a parameter included in the model formula to reduce at least one of a difference between an estimate value and a measurement value of the oxygen concentration and a difference between an estimate value and a measurement value of the carbon dioxide gas concentration of the exhaust gas; estimating the carbon concentration of the molten steel by using the model formula in which the parameter is corrected; and determining timing when an estimate value reaches a target value as the completion time point of the vacuum decarburization treatment.

The present application concerns in-situ intrusive probe systems and methods. The probe systems described herein can be installed flush to a hydrocarbon containing structure, such as a pipeline, vessel, or other piping system carrying crude, gas or sour products. The probe systems include hydrogen induced cracking (HIC)-resistant microstructure such that as atomic hydrogen permeates the probe surface, the probe captures recombined hydrogen gas. The pressure of the resultant hydrogen gas buildup is measured and predictions as to the HIC activity of that area can be made.

The present application concerns in-situ intrusive probe systems and methods. The probe systems described herein can be installed flush to a hydrocarbon containing structure, such as a pipeline, vessel, or other piping system carrying crude, gas or sour products. The probe systems include hydrogen induced cracking (HIC)-resistant microstructure such that as atomic hydrogen permeates the probe surface, the probe captures recombined hydrogen gas. The pressure of the resultant hydrogen gas buildup is measured and predictions as to the HIC activity of that area can be made.

The present invention relates to an apparatus for demolding and analyzing a direct analysis sample formed from a molten metal material contained within a sample chamber assembly, wherein the sample chamber assembly comprises at least a sample housing, a cover plate and closing means, comprising: a cabinet defining an interior and comprising at least one opening for the sample housing to enter the cabinet, and analyzing means located inside the cabinet for analyzing an analysis surface of the sample; demolding means adapted to remove at least the closing means to expose at least part of the analysis surface of the sample; and transporting means adapted to hold and transport the sample housing at least between a sample demolding position, where the closing means is removed by the demolding means, and a sample analysis position, where the analysis surface of the sample is analyzed by the analyzing means, and wherein the sample demolding position and the sample analysis position are different from each other. The invention also relates to a system and method for demolding and analyzing a direct analysis sample.

The present invention relates to an apparatus for demolding and analyzing a direct analysis sample formed from a molten metal material contained within a sample chamber assembly, wherein the sample chamber assembly comprises at least a sample housing, a cover plate and closing means, comprising: a cabinet defining an interior and comprising at least one opening for the sample housing to enter the cabinet, and analyzing means located inside the cabinet for analyzing an analysis surface of the sample; demolding means adapted to remove at least the closing means to expose at least part of the analysis surface of the sample; and transporting means adapted to hold and transport the sample housing at least between a sample demolding position, where the closing means is removed by the demolding means, and a sample analysis position, where the analysis surface of the sample is analyzed by the analyzing means, and wherein the sample demolding position and the sample analysis position are different from each other. The invention also relates to a system and method for demolding and analyzing a direct analysis sample.

Apparatuses and methods of measuring a hydrogen diffusivity of a metal structure including during operation of the metal structure, are provided. A hydrogen charging surface is provided at a first location on an external surface of the structure. In addition, a hydrogen oxidation surface is provided at a second location adjacent to the first location on the external surface of the structure. Hydrogen flux is generated and directed into the metal surface at the charging surface. At least a portion of the hydrogen flux generated by the charging surface is diverted back toward the surface. A transient of the diverted hydrogen fluxes measured, and this measurement is used to determine the hydrogen diffusivity of the metal structure in service.