Abstract: The present invention provides a method for sensing whether carburization occurs or not on an inner surface of a pipe or tube by an electromagnetic testing, comprising: a first step of inserting a carburized tube P0 into an excitation coil 11 and into a detection coil 12, and determining a value of a parameter K; and a second step of setting conditions of the excitation coil so as to obtain the value of the parameter K determined in the first step, and thereafter, inserting a pipe or tube that is an inspection target into the excitation coil 11 and into the detection coil 12 and sensing whether carburization occurs or not on an inner surface of the pipe or tube based on an output signal outputted from the detection coil 12.

Abstract: The present invention provides a method for sensing whether carburization occurs or not on an inner surface of a pipe or tube by an electromagnetic testing, comprising: a first step of inserting a carburized tube P0 into an excitation coil 11 and into a detection coil 12, and determining a value of a parameter K; and a second step of setting conditions of the excitation coil so as to obtain the value of the parameter K determined in the first step, and thereafter, inserting a pipe or tube that is an inspection target into the excitation coil 11 and into the detection coil 12 and sensing whether carburization occurs or not on an inner surface of the pipe or tube based on an output signal outputted from the detection coil 12.

Abstract: A carburization sensing method according to the present invention includes: a first procedure of attaching a magnetic material to a reference material which has equivalent electromagnetic properties to those of a test material and is not carburized, a second procedure of measuring magnetic strength of each magnetic material and to acquire an electromagnetic test output value for each magnetic material, a third procedure of calculating a correlation between the measured magnetic strength value and the electromagnetic test output value, a fourth procedure of measuring magnetic strengths on a plurality of carburized materials, a fifth procedure of calculating a correlation between a carburized depth and the measured magnetic strength value, a sixth procedure of determining a threshold value Th2 of the measured magnetic strength value corresponding to a threshold value Th1 of the carburized depth to be sensed, a seventh procedure of determining a threshold value Th3 of an electromagnetic test output value corresp

Abstract: A carburization sensing method according to the present invention includes: a first procedure of attaching a magnetic material to a reference material which has equivalent electromagnetic properties to those of a test material and is not carburized, a second procedure of measuring magnetic strength of each magnetic material and to acquire an electromagnetic test output value for each magnetic material, a third procedure of calculating a correlation between the measured magnetic strength value and the electromagnetic test output value, a fourth procedure of measuring magnetic strengths on a plurality of carburized materials, a fifth procedure of calculating a correlation between a carburized depth and the measured magnetic strength value, a sixth procedure of determining a threshold value Th2 of the measured magnetic strength value corresponding to a threshold value Th1 of the carburized depth to be sensed, a seventh procedure of determining a threshold value Th3 of an electromagnetic test output value corresp