CN113375606A

CN113375606A - Maintenance device

Info

Publication number: CN113375606A
Application number: CN202010606391.7A
Authority: CN
Inventors: 米川荣; S·阿; A·R·奈尔
Original assignee: Toshiba Corp; Toshiba Infrastructure Systems and Solutions Corp
Current assignee: Toshiba Corp; Toshiba Infrastructure Systems and Solutions Corp
Priority date: 2020-03-10
Filing date: 2020-06-29
Publication date: 2021-09-10
Anticipated expiration: 2040-06-29
Also published as: TWI752533B; TW202133788A; KR102385322B1; CN113375606B; KR20210114311A; JP2021144925A

Abstract

A maintenance device for improving the accuracy of determining an abnormality level includes a diagnostic unit for detecting a peak of measurement information including at least one of the following detection results: a detection result of a tube voltage between the filament and the target, the filament emitting electrons by power from the X-ray control power source, and the target irradiating X-rays to the object to be measured having a thickness by collision of the electrons emitted from the filament; a detection result of a tube current flowing between the filament and the target; a detection result of a detection signal of at least one of a detection voltage and a detection current corresponding to the intensity of the X-ray passing through the object to be measured; a detection result of a primary side driving voltage of a transformer for transforming the power from the X-ray control power supply and supplying the transformed power to the filament; and a detection result of the driving current flowing through the primary side of the transformer. The diagnosis unit determines an abnormality level of an X-ray thickness measurement device for calculating the thickness of the measurement object based on the detection signal, based on the product of the frequency of occurrence of the peak and the size of the peak.

Description

Maintenance device

Technical Field

Embodiments of the present invention relate to a maintenance device.

Background

As one type of thickness gauge, there is an X-ray thickness measuring apparatus that measures the thickness of a steel sheet to be measured in various steel sheet manufacturing lines. An X-ray thickness measuring device measures the thickness of a measured object on line in an iron-non-iron rolling line operating for 24 hours.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2010-167282

Disclosure of Invention

Problems to be solved by the invention

However, although the X-ray thickness measuring apparatus includes an X-ray generator that irradiates a measurement target such as a steel plate with X-rays, if the X-ray generator fails, the thickness of the measurement target cannot be measured, and the thickness of the measurement target in the manufacturing line cannot be controlled or monitored. Therefore, it is required to replace the X-ray generator before the X-ray generator fails to reduce the influence of the failure of the X-ray generator on the manufacturing line.

Means for solving the problems

The maintenance device of the embodiment is provided with a diagnosis part. The diagnostic unit detects a peak of measurement information including at least one of the following detection results: a detection result of a tube voltage between a filament that emits electrons by power from an X-ray control power source and a target that irradiates X-rays to a measurement object having a thickness by collision of electrons emitted from the filament; a detection result of a tube current flowing between the filament and the target; a detection result of a detection signal of at least one of a detection voltage and a detection current corresponding to the intensity of the X-ray that has passed through the measurement object; a detection result of a primary-side drive voltage of a transformer that transforms power from the X-ray control power supply and supplies the transformed power to the filament; and a detection result of the driving current flowing through the primary side of the transformer. The diagnostic unit determines an abnormality level of the X-ray thickness measuring apparatus for calculating the thickness of the measurement target based on the detection signal, based on the product of the frequency of occurrence of the peak and the size of the peak.

Drawings

Fig. 1 is a schematic diagram showing an example of the overall configuration of the X-ray thickness measurement system according to the present embodiment.

Fig. 2 is a block diagram showing an example of a functional configuration of a control system of the X-ray thickness measurement system according to the present embodiment.

Fig. 3 is a diagram for explaining an example of the process of setting the variation range of the X-ray thickness measurement system according to the present embodiment.

Fig. 4 is a diagram for explaining an example of the outlier removal processing of the X-ray thickness measurement system according to the present embodiment.

Fig. 5 is a diagram for explaining an example of the process of correcting the skewness of the houtt management map or the R management map of the X-ray thickness measurement system according to the present embodiment.

Fig. 6 is a diagram showing an example of an R management diagram of tube voltage created by the X-ray thickness measurement system according to the present embodiment.

Fig. 7 is a diagram showing an example of a peak of the tube voltage TV detected by the X-ray thickness measurement system according to the present embodiment.

Fig. 8 is a diagram showing an example of a peak of the tube voltage TV detected by the X-ray thickness measurement system according to the present embodiment.

Fig. 9 is a diagram showing an example of the frequency of occurrence of a peak in tube voltage detected by the X-ray thickness measurement system according to the present embodiment.

Fig. 10 is a diagram showing an example of the magnitude of the peak of the tube voltage detected by the X-ray thickness measurement system according to the present embodiment.

Fig. 11 is a diagram showing an example of a calculation result of a product of the generation frequency and the magnitude of the peak of the tube voltage in the X-ray thickness measurement system according to the present embodiment.

Fig. 12 is a diagram showing an example of the cumulative sum of the frequencies of occurrence of the spikes of the tube voltage detected by the X-ray thickness measurement system of the present embodiment.

Fig. 13 is a diagram showing an example of the sum of the magnitudes of the peaks of the tube voltage detected by the X-ray thickness measurement system according to the present embodiment.

Fig. 14 is a diagram showing an example of a calculation result of a product of the cumulative sum of the generation frequencies and the cumulative sum of the magnitudes of the peaks of the tube voltage in the X-ray thickness measurement system according to the present embodiment.

Fig. 15 is a diagram showing an example of a gradiometer (Level meter) for an abnormality Level displayed by the X-ray thickness measurement system of the present embodiment.

Fig. 16 is a flowchart showing an example of the flow of the calculation process of the upper limit management limit and the lower limit management limit of the X-ray thickness measurement system according to the present embodiment.

Fig. 17 is a flowchart showing an example of the flow of the abnormality level determination process of the X-ray thickness measurement device in the X-ray thickness measurement system according to the present embodiment.

Detailed Description

The following exemplary embodiments and modifications include the same components. Accordingly, the same components are denoted by the same reference numerals and overlapping descriptions are partially omitted. Portions included in the embodiment and the modification can be replaced with corresponding portions in other embodiments and modifications. Unless otherwise specified, the configurations, positions, and the like of portions included in the embodiments and the modifications are the same as those of the other embodiments and modifications.

First, an example of the overall configuration of the X-ray thickness measurement system according to the present embodiment will be described with reference to fig. 1.

The X-ray thickness measurement system 10 measures the thickness of the measurement object 90 (for example, a steel plate) by the X-ray thickness measurement device 12, and generates and accumulates the precursor data 68 (see fig. 2) necessary for diagnosing the abnormality of the X-ray thickness measurement device 12 to diagnose the abnormality of the X-ray thickness measurement device 12.

As shown in fig. 1, an X-ray thickness measurement system 10 according to the present embodiment includes an X-ray thickness measurement device 12, a prognostic data server 14, a maintenance device 16, and a network 18. The Network 18 is a LAN (Local Area Network) or the like that connects the X-ray thickness measurement device 12, the premonition data server 14, and the maintenance device 16 so as to be able to transmit and receive information to and from each other. The X-ray thickness measurement system 10 according to the present embodiment can communicate with a host device provided outside the X-ray thickness measurement system 10 via a network such as the internet according to a communication standard such as TCP/IP.

The X-ray thickness measuring device 12 irradiates the object 90 having a thickness with X-rays, and measures the thickness of the object 90 based on the amount of X-rays that have passed through the object 90. The X-ray thickness measuring device 12 includes a measuring unit 20, an X-ray control power source 22, and a plate thickness calculating unit (control device) 24.

The measuring unit 20 irradiates the measurement object 90 with X-rays, and outputs at least one of a detection voltage and a detection current for calculating the thickness of the measurement object 90 to the plate thickness calculation unit 24 as a detection value. The measuring unit 20 of the present embodiment includes a holding unit 26, a transformer 28, an X-ray generator 30, a detector 32, an output detecting unit 34, a resistor 35, a transformer 37, and booster circuits 39a and 39 b.

The holding unit 26 holds the transformer 28, the X-ray generator 30, the detector 32, the output detection unit 34, the resistor 35, the transformer 37, and the booster circuits 39a and 39 b.

The transformer 28 transforms (for example, boosts) the power output from the X-ray control power source 22 and supplies the power to a filament 38 of an X-ray generator 30, which will be described later.

The transformer 37 transforms (boosts) the voltage across the resistor 35.

The booster circuit 39a is a booster circuit that boosts the voltage applied to one end (end on the filament 38 side) of the transformer 37.

The booster circuit 39b is a booster circuit that boosts the voltage applied to the other end (end on the target 40 side) of the transformer 37.

The X-ray generator 30 generates X-rays by the electric power supplied from the X-ray control power source 22, and irradiates the object to be measured 90 with the X-rays. The X-ray generator 30 of the present embodiment includes an X-ray tube 36, a filament 38, and a target 40.

The X-ray tube 36 is, for example, a sealed tube that maintains the inside in a vacuum state. The X-ray tube 36 accommodates and holds a filament 38 and a target 40 inside. The filament 38 discharges electrons to the target 40 by the power supplied from the X-ray control power supply 22 via the transformer 28. The target 40 irradiates the measurement object 90 with X-rays by collision of electrons emitted from the filament 38.

The detector 32 is disposed at a position facing the X-ray generator 30 with the measurement object 90 interposed therebetween. The detector 32 of the present embodiment outputs at least one of a detection voltage and a detection current corresponding to the intensity of the X-rays irradiated from the X-ray generator 30 and passed through the measurement object 90 to the output detection unit 34 as a detection signal. The detector 32 may be, for example, an ionization chamber that outputs a detection voltage and a detection current corresponding to the incident X-ray.

The output detection unit 34 performs conversion processing on the detection signal output from the detector 32 and outputs the result to the sheet thickness calculation unit 24. For example, the output detection unit 34 may include an AD converter or the like, and output a value obtained by digitally converting a detection signal of an analog signal as a detection value for calculating the thickness of the measurement object 90.

The X-ray control power supply 22 is an example of a power supply, and supplies power to the filament 38 of the X-ray generator 30 via the transformer 28 based on a power supply control signal from the plate thickness calculation unit 24. The X-ray control power source 22 may be connected to an external power source such as a commercial power source. The X-ray control power source 22 includes a drive detection unit 42 and a tube detection unit 44.

The drive detection unit 42 detects a drive voltage and a drive current. The drive voltage is a value of a voltage of the primary side of the transformer 28, and is a value of a voltage of the power supplied by the X-ray control power source 22. The drive current is a value of a current flowing through the primary side of the transformer 28, and is a value of a current of the power supplied by the X-ray control power source 22. The drive detection unit 42 outputs the drive voltage and the drive current sensed (detected) to the plate thickness calculation unit 24.

In the present embodiment, the drive detection unit 42 acquires Time stamp data, which is a Time stamp at the Time of detection of the drive voltage and the drive current, from an RTC (Real Time Clock), not shown, included in the X-ray control power source 22. Then, the drive detection unit 42 adds the acquired time data to the detected drive voltage and drive current, and outputs the result to the plate thickness calculation unit 24.

The tube detection unit 44 detects a tube voltage and a tube current. The tube voltage is the value of the voltage on the secondary side of the transformer 28 and is the value of the voltage between the filament 38 and the target 40. The tube current is a value of a current flowing through the secondary side of the X-ray generator 30, and is a value of a current flowing between the filament 38 and the target 40.

In the present embodiment, the tube detection unit 44 detects a voltage across the resistor 35 as a tube voltage, and detects a value of a current flowing through the resistor 35 as a tube current. Then, the tube detection unit 44 outputs the tube voltage and the tube current sensed (detected) to the plate thickness calculation unit 24.

In the present embodiment, the tube detection unit 44 acquires time data, which is a time stamp at the time of detection of the tube voltage and the tube current, from an RTC, not shown, included in the X-ray control power supply 22. Then, the tube detection unit 44 adds the acquired time data to the detected tube voltage and tube current, and outputs the result to the plate thickness calculation unit 24.

The plate thickness calculation unit 24 is responsible for overall control of the X-ray thickness measurement device 12. The plate thickness calculation unit 24 may be a computer used by an operator or the like for measuring the thickness of the measurement object 90 by the X-ray thickness measuring device 12.

Specifically, the plate thickness calculation unit 24 calculates the thickness of the measurement object 90 based on the detection value acquired from the output detection unit 34.

The plate thickness calculation unit 24 outputs a power supply control signal indicating a drive voltage corresponding to the tube voltage of the power supplied to the X-ray generator 30 to the X-ray control power supply 22. The plate thickness calculation unit 24 may generate a power supply control signal for instructing a drive voltage set based on the tube voltage acquired from the tube detection unit 44.

The plate thickness calculation unit 24 outputs measurement information 56 (see fig. 2) including at least one of the detection result of the detection value output from the output detection unit 34, the detection result of the drive voltage by the drive detection unit 42, the detection result of the drive current by the drive detection unit 42, the detection result of the tube voltage by the tube detection unit 44, and the detection result of the tube current by the tube detection unit 44 to the network 18. In the present embodiment, the plate thickness calculation unit 24 outputs measurement information 56 including a detection value, a driving voltage, a driving current, a maximum value, a minimum value, and an average value of each of the tube voltage and the tube current, which are set in advance for each period (for example, 100ms), to the network 18. The plate thickness calculation unit 24 may output the measurement information 56 by broadcasting, for example.

In the present embodiment, the plate thickness calculation unit 24 outputs the measurement information 56 including the detection value obtained from the output detection unit 304 and the detection value of the thickness of the measurement object 90, but the present invention is not limited to this as long as the measurement information 56 including at least one of the detection value and the thickness of the measurement object 90 is output. For example, the plate thickness calculation unit 24 may output the measurement information 56 including both the detection value and the thickness of the measurement object 90, or may output the measurement information 56 including the thickness of the measurement object 90 instead of the detection value.

In the present embodiment, the plate thickness calculation unit 24 outputs the measurement information 56 including the maximum value, the minimum value, and the average value of the detected value, the driving voltage, the driving current, the tube voltage, and the tube current to the network 18, but it is sufficient to output the measurement information 56 including at least the maximum value and the minimum value of the maximum value, the minimum value, and the average value of the detected value, the driving voltage, the driving current, the tube voltage, and the tube current to the network 18.

The sign data server 14 repeatedly acquires the measurement information 56 from the plate thickness calculation unit 24 a plurality of times, and stores and accumulates data 68 (hereinafter, referred to as sign data, see fig. 2) indicating a sign of an abnormality of the X-ray thickness measurement device 12, which is generated from the plurality of measurement information 56. Here, the prognostic data 68 is statistics of the measurement information 56 acquired from the X-ray thickness measurement device 12. Then, the prognostic data server 14 outputs the measurement information 56 and the prognostic data 68 in response to a request from the maintenance device 16.

The maintenance device 16 is, for example, a computer used by a maintenance person or the like who maintains the X-ray thickness measuring device 12. The maintenance device 16 diagnoses an abnormality of the X-ray thickness measurement device 12 based on the measurement information 56 and the prognostic data 68 acquired from the prognostic data server 14, and outputs the result of the diagnosis as an image or the like.

First, an example of the functional configuration of the plate thickness calculating unit 24 included in the X-ray thickness measuring device 12 will be described with reference to fig. 2.

As shown in fig. 2, the plate thickness calculation unit 24 includes a control-side processing unit 46 and a control-side storage unit 48.

The control-side processing unit 46 is responsible for overall control of the X-ray thickness measuring apparatus 12. The control-side Processing Unit 46 may be a hardware processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit) that executes arithmetic Processing or the like. The control-side processing unit 46 reads a program stored in the control-side storage unit 48, and executes various kinds of arithmetic processing by developing the read program in the control-side storage unit 48.

The control-side processing unit 46 reads, for example, the measurement program 54, and functions as a reception unit 50 and a calculation unit 52. The reception unit 50 and the calculation unit 52 may be partly or entirely configured by hardware such as a Circuit including an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array).

The reception unit 50 receives the measurement information 56 and outputs the measurement information to the calculation unit 52. The reception unit 50 receives, for example, the detection value output from the output detection unit 34, the drive voltage detected by the drive detection unit 42, the drive current detected by the drive detection unit 42, the tube voltage detected by the tube detection unit 44, and the tube current detected by the tube detection unit 44 as the measurement information 56.

When the measurement information 56 is acquired from the reception unit 50, the calculation unit 52 calculates the thickness of the measurement object 90 based on the measurement information 56, and controls the X-ray thickness measurement device 12. For example, the calculation unit 52 calculates the thickness of the measurement object 90 based on the detection value. In the present embodiment, the calculation unit 52 acquires the detection value from the output detection unit 34, and calculates the thickness of the measurement object 90 each time the detection value is acquired.

In the present embodiment, the calculation unit 52 acquires time data, which is a time stamp at the time of detection of the detection value, from an RTC, not shown, which the plate thickness calculation unit 24 has. Then, the calculation unit 52 adds the acquired time data to the acquired detection value and the calculated thickness of the measurement object 90. The calculation unit 52 generates and outputs a power supply control signal for instructing the X-ray control power supply 22 to set the tube voltage and the tube current to preset voltages. The calculation unit 52 outputs the measurement information 56 to the network 18 by broadcasting.

The control-side storage unit 48 includes a main storage device such as a ROM (Read Only Memory), a RAM (Random Access Memory), and an HDD (Hard Disk Drive), and an auxiliary storage device. The control-side storage unit 48 stores a measurement program 54 executed by the control-side processing unit 46, measurement information 56 obtained by executing the measurement program 54, and the like. The measurement program 54 may be stored in a computer-readable storage medium such as a CD-ROM (Compact Disc Read Only Memory) or a DVD-ROM (Digital Versatile Disc Read Only Memory), or may be provided via a network such as the internet.

Next, an example of the functional configuration of the predictive data server 14 will be described with reference to fig. 2. As shown in fig. 2, the sign data server 14 includes a sign-side processing unit 58 and a sign-side storage unit 60.

The precursor-side processing unit 58 is responsible for overall control of the precursor data server 14. The precursor-side processing unit 58 may be a hardware processor such as a CPU or a GPU. The precursor-side processing unit 58 reads a program stored in the precursor-side storage unit 60, and develops the read program in the precursor-side storage unit 60 to execute various kinds of arithmetic processing. The precursor-side processing unit 58 reads, for example, the precursor program 66, and functions as the acquisition unit 62 and the precursor unit 64. Part or all of the acquisition unit 62 and the warning unit 64 may be configured by hardware such as a circuit including an ASIC or an FPGA.

The acquisition unit 62 acquires the measurement information 56 from the X-ray thickness measurement device 12. The acquisition unit 62 of the present embodiment acquires the measurement information 56 including at least one parameter (detection result) of the drive voltage, the drive current, the tube voltage, the tube current, and the detection value flowing through the network 18, and to which time data at the time of detection or calculation of the parameter is added, a plurality of times, and outputs the measurement information to the warning unit 64.

The acquisition unit 62 of the present embodiment acquires the measurement information 56 from the X-ray thickness measurement device 12 at a cycle longer than the time required for generating the precursor data 68 by the precursor unit 64 described later. That is, the period of time for the acquisition unit 62 to acquire the measurement information 56 is longer than the time required for the generation of the warning data 68 by the warning unit 64. This can prevent a processing load applied to the precursor data server 14 from increasing due to generation of the precursor data 68 by the precursor unit 64, and further prevent failure in acquisition of the measurement information 56 from the X-ray thickness measurement device 12.

The warning unit 64 writes the measurement information 56 acquired by the acquisition unit 62 into the warning-side storage unit 60. Then, the warning unit 64 generates statistics of the measurement information 56 as warning data 68. Then, the sign unit 64 writes the generated sign data 68 in the sign-side storage unit 60.

In response to a request from maintenance device 16, warning unit 64 outputs measurement information 56 and warning data 68 accumulated in warning-side storage unit 60. The warning unit 64 notifies the generated warning data 68 to an external higher-level device according to a communication standard such as analog or TCP/IP.

The warning-side storage unit 60 includes a main storage device such as a ROM, a RAM, and an HDD, and an auxiliary storage device. The precursor-side storage unit 60 stores a precursor program 66 executed by the precursor-side processing unit 58, precursor data 68 generated by the execution of the precursor program 66, and the like. The warning program 66 may be stored in a computer-readable storage medium such as a CD-ROM or a DVD-ROM, or may be provided via a network such as the internet.

Next, an example of the functional configuration of the maintenance device 16 will be described with reference to fig. 2.

As shown in fig. 2, the maintenance device 16 includes a maintenance-side processing unit 70, a maintenance-side storage unit 72, and a display unit 73.

The maintenance-side processing unit 70 is responsible for overall control of the maintenance device 16. The maintenance-side processing unit 70 may be a hardware processor such as a CPU or a GPU. The maintenance-side processing unit 70 reads a program stored in the maintenance-side storage unit 72, and executes various kinds of arithmetic processing by expanding the read program in the maintenance-side storage unit 72. The maintenance-side processing unit 70 reads a maintenance program 76, for example, and functions as a diagnosis unit 74. Part or all of the diagnostic unit 74 may be configured by hardware such as a circuit including an ASIC or an FPGA.

Diagnostic unit 74 acquires measurement information 56 and warning data 68 output from warning data server 14. In the present embodiment, the diagnostic unit 74 acquires the measurement information 56 output from the precursor data server 14, but is not limited to this, and may acquire the measurement information 56 output from the X-ray thickness measurement device 12 (plate thickness calculation unit 24).

The diagnosis unit 74 diagnoses an abnormality of the X-ray thickness measuring device 12 based on the acquired measurement information 56. Specifically, the diagnosing unit 74 obtains the product of the frequency of occurrence of the peak and the size of the peak in the measurement information 56 based on the measurement information 56. Next, the diagnosis unit 74 determines the abnormality level of the X-ray thickness measurement device 12 based on the obtained product. Here, the abnormality level is a level at which the X-ray thickness measuring device 12 is close to a failure state.

From the experimental results, it is understood that the peaks of the measurement information 56 include two types of peaks, i.e., a very large peak generated discretely and a small peak generated continuously. Therefore, the abnormality level of the X-ray thickness measurement device 12 is preferably determined by considering both the frequency of occurrence of the peak in the measurement information 56 and the size of the peak.

Therefore, the diagnosis unit 74 determines the abnormality level of the X-ray thickness measurement device 12 based on the product of the frequency of occurrence of the peak in the measurement information 56 and the size of the peak, as described above. Thus, even when one type of a very large peak that occurs discretely or a small peak that occurs continuously occurs is generated in the measurement information 56, the detection results of the two types of peaks can be reflected in the determination of the abnormality level of the X-ray thickness measurement device 12. As a result, the accuracy of determining the abnormality level of the X-ray thickness measuring device 12 can be improved.

In the present embodiment, the diagnosing unit 74 first removes transition period data from the acquired measurement information 56. Here, the transition period data is the measurement information 56 during the transition period in which the measurement information 56 (for example, the tube voltage) is changed. For example, the diagnostic unit 74 removes the transition period data from the initial measurement information 56 among the acquired measurement information 56. Here, the initial measurement information 56 is, for example, measurement information 56 from the start of the X-ray thickness measurement device 12 to the elapse of a predetermined time (for example, 1 minute or 10 minutes).

Next, the diagnosis unit 74 sets the difference between the maximum value and the minimum value included in the initial measurement information 56 from which the transition period data is removed, as shown in the following expression (1), as the variation range of the measurement information 56. In the present embodiment, the diagnostic unit 74 sets the variation range of the measurement information 56 every 100 ms. The diagnosing unit 74 then removes outliers from the range of variation of the measurement information 56. Next, the diagnostic unit 74 creates a houtt management map or an R management map from which the outliers have been removed, and performs distortion correction on the houtt management map or the R management map.

Variation range (maximum value of measurement information 56) - (minimum value of measurement information 56) · (1)

Then, the diagnosis unit 74 determines the upper limit management limit UCL and the lower limit management limit LCL of the variation range of the measurement information 56 based on the houtt management map or the R management map subjected to the distortion correction. Thus, even when the measurement information 56 includes unnecessary data or the measurement information 56 includes distortion, it is possible to obtain an appropriate upper limit management limit UCL and lower limit management limit LCL using the houtt management map or the R management map subjected to the distortion correction and detect a peak of the measurement information 56. As a result, the accuracy of determining the abnormality level of the X-ray thickness measuring apparatus can be improved. The diagnostic unit 74 determines the upper limit management limit UCL and the lower limit management limit LCL for the respective variation ranges of the drive voltage, the drive current, the tube voltage, the tube current, and the detection value included in the measurement information 56.

Then, the diagnosing unit 74 detects, as a peak, the measurement information 56 having a variation range exceeding the upper limit management limit UCL or the lower limit management limit LCL, among the measurement information 56 to be detected for the peak. Here, the measurement information 56 of the peak detection target is, for example, the measurement information 56 after a predetermined time has elapsed after the start of the X-ray thickness measuring apparatus 12.

The diagnostic unit 74 generates an indicator (hereinafter, referred to as a "gradiometer") indicating the abnormality level of the X-ray thickness measuring apparatus 12, and displays the generated gradiometer on the display unit 73. The display unit 73 displays the warning data 68 output from the warning data server 14, various information such as a level meter, and the like.

The maintenance-side storage unit 72 includes a main storage device such as a ROM, a RAM, and an HDD, and an auxiliary storage device. The maintenance-side storage unit 72 stores a maintenance program 76 and the like executed by the maintenance-side processing unit 70. The maintenance program 76 may be stored in a computer-readable storage medium such as a CD-ROM or a DVD-ROM, or may be provided via a network such as the internet.

Next, a specific example of the process of calculating the upper limit management limit UCL and the lower limit management limit LCL by the diagnostic unit 74 of the maintenance device 16 will be described. In the following description, an example in which the diagnosis section 74 calculates the upper limit management limit UCL and the lower limit management limit LCL of the tube voltage TV as an example of the measurement information 56 is described, but the upper limit management limit UCL and the lower limit management limit LCL are also calculated from the tube current, the drive voltage, the drive current, and the detection value in the same manner.

First, a process of removing the transition period data from the initial tube voltage TV (an example of the initial measurement information 56) by the diagnosis unit 74 will be described.

When changing the tube voltage TV from a certain set value to another set value, it may take several seconds until the tube voltage TV detected by the tube detection unit 44 is stabilized. Therefore, when changing the set value of the tube voltage TV, the diagnostic unit 74 removes the tube voltage TV (an example of transition period data) in the transition period required until the tube voltage TV detected by the tube detection unit 44 is stabilized from the tube voltage TV used for calculation of the upper limit management limit UCL and the lower limit management limit LCL. However, when the transition period data is already removed from the tube voltage TV acquired from the predictive data server 14, the diagnostic unit 74 may not perform the process of removing the transition period data from the tube voltage TV.

In the present embodiment, the diagnostic unit 74 removes transition period data from the tube voltage TV using a local maximum value (local maximum). Specifically, the diagnosis unit 74 converts the average of the tube voltage TV into an absolute gradient value, and sets a threshold value of the tube voltage TV determined as the transition period data based on the absolute gradient value. Next, the diagnosis unit 74 extracts the tube voltages TV exceeding the set threshold value among the tube voltages TV, and removes a set of tube voltages TV different from the adjacent tube voltages TV among the extracted tube voltages TV as transition period data. Here, the adjacent tube voltage TV is a set value of the tube voltage TV closest to the extracted tube voltage TV among the set values of the tube voltage TV that can be applied between the filament 38 and the target 40.

Alternatively, in the present embodiment, the diagnosis section 74 removes the transition period data from the tube voltage TV using batch averaging. Specifically, when there are a plurality of set values (for example, 60kV, 80kV, 100kV, 110kV, 120kV, 130kV, and 140kV) of the tube voltage TV that can be applied between the filament 38 and the target 40, and the allowable limit of each set value is ± 1kV, the diagnostic unit 74 calculates the average of the tube voltages TV (for example, 200 tube voltages TV) actually detected by the tube detection unit 44 for each set value of the tube voltage TV. Then, the diagnosis unit 74 removes, as transition period data, the tube voltage TV that does not match the average of the tube voltages TV calculated for the set values of the tube voltages TV.

Next, an example of processing for setting the initial variation range of the tube voltage TV by the diagnosis unit 74 will be described.

In the present embodiment, the diagnostic unit 74 sets the difference between the minimum value and the maximum value of the tube voltage TV per 100ms acquired from the prognostic data server 14 as the variation range of the tube voltage TV.

Fig. 3 is a diagram for explaining an example of the process of setting the variation range of the X-ray thickness measurement system according to the present embodiment. In fig. 3, the vertical axis represents the variation range of the tube voltage TV, and the horizontal axis represents data points that can identify the detection result of the tube voltage TV for each predetermined period (for example, 100 ms).

In the present embodiment, the diagnostic unit 74 sets the difference between the maximum value TVmax and the minimum value TVmin of the tube voltage TV for each data point as the variation range of the tube voltage TV as shown in fig. 3.

Next, an example of processing for removing outliers from the initial fluctuation range of the tube voltage TV by the diagnosis unit 74 will be described.

In the present embodiment, the diagnostic unit 74 removes outliers using an Interquartile Range (IQR) from a variation Range of the tube voltage TV until a predetermined period elapses since the replacement of the X-ray generator 30. Specifically, the diagnosis unit 74 removes, as outliers (abnormal values), the fluctuation ranges outside 1.5 qr of 75 percentiles (3 rd quartile) and 25 percentile (1 st quartile) in the fluctuation range of the tube voltage TV.

Fig. 4 is a diagram for explaining an example of the outlier removal processing of the X-ray thickness measurement system according to the present embodiment. In fig. 4, the vertical axis represents the variation range of the tube voltage TV, and the horizontal axis represents data points that can identify the detection result of the tube voltage TV for each predetermined period.

The diagnostic unit 74 eliminates, as outliers, the fluctuation ranges outside 1.5 ANGSTROM of 75 percentile and 25 percentile, respectively, in the fluctuation range of the tube voltage TV. Thus, as shown in fig. 4, it is understood that the fluctuation range of the tube voltage TV varies before and after the outlier is removed, and the spike that may occur in the normal tube voltage TV is deleted from the tube voltage TV used for the calculation of the upper limit management limit UCL and the lower limit management limit LCL.

In the present embodiment, the diagnosis unit 74 removes outliers using a trimmed mean value from a variation range of the tube voltage TV after the X-ray generator 30 is replaced and a predetermined time elapses. Specifically, the diagnostic unit 74 sorts the variation range of the tube voltage TV in ascending order, and then removes the variation range of the tube voltage TV at a predetermined ratio from each of the minimum value and the maximum value as an outlier. When the data set of the tube voltage TV acquired by the acquiring unit 62 is an unstable data set or when the data set of the tube voltage TV has an extremely uneven distribution, the diagnosing unit 74 removes an outlier from the variation range of the tube voltage TV using a trimmed mean value. Thus, a Huhatt management graph or an R management graph having a target sigma limit can be created.

In order to remove outliers from the range of variation of the tube voltage TV, either of the two methods described above can be used. The peak of the tube voltage TV until the initial period of the life cycle of the X-ray generator 30 is very small, and the outlier thereof can be removed by the IQR. Therefore, the diagnosis unit 74 removes outliers from the variation range of the tube voltage TV after the X-ray generator 30 is replaced and a predetermined period elapses by the IQR.

On the other hand, if the outlier is removed from the variation range of the tube voltage TV in the second half of the life cycle of the X-ray generator 30 by the IQR, the number of spikes increases, and in the calculation of the upper limit management limit UCL and the lower limit management limit LCL, the spike caused when the life cycle of the X-ray generator 30 becomes the second half may be considered in the determination of the abnormality level. Therefore, the diagnosis unit 74 removes outliers using the trimmed mean from the variation range of the tube voltage TV after the X-ray generator 30 is replaced and a predetermined period has elapsed.

Next, a process of creating a houttt management map or an R management map of the initial fluctuation range of the tube voltage TV by the diagnosis unit 74 will be described.

First, the diagnosis unit 74 creates a houtts management map or an R management map from which the variation range of the outliers is removed. The houtt management map and the R management map are powerful tools that can be used easily for statistical management of the measurement information 56. Further, the houtt management chart and the R management chart are widely used and applied to the industrial field.

However, the houtt management map and the R management map are assumed to be based on the assumption that the distribution of the measurement information 56 subjected to statistical management is normal distribution or substantially normal distribution. However, the measurement information 56 is information indicating the life cycle of the X-ray generator 30. Therefore, the amount of noise in the measurement information 56 during a certain period (for example, the second half of the life cycle of the X-ray generator 30) increases due to deterioration of the X-ray generator 30. Thus, the probability distribution of the data set of the measurement information 56 is often represented as a gamma distribution or a weibull distribution that is inclined to the right.

Fig. 5 is a diagram for explaining an example of the process of correcting the skewness of the houtt management map or the R management map of the X-ray thickness measurement system according to the present embodiment. In fig. 5, the vertical axis represents the number of detection results of the tube voltage TV, and the horizontal axis represents the variation range of the tube voltage TV.

As shown in fig. 5, the distribution of the variation range of the tube voltage TV from which the outliers are removed is represented by a gamma distribution or a weibull distribution in which the variation range of the tube voltage TV is larger than the average of the variation range of the tube voltage TV. Therefore, if the upper limit management limit UCL and the lower limit management limit LCL are calculated using the houtt's management map or the R management map without correcting the skewness of the houtt's management map or the R management map, the detection accuracy of the peak may be degraded due to an abnormality of the X-ray thickness measuring device 12.

Therefore, in the present embodiment, the diagnosis unit 74 corrects the skewness of the houtts management diagram or the R management diagram of the tube voltage TV. Thus, the upper limit management limit UCL and the lower limit management limit LCL can be calculated using the houtt management chart or the R management chart created on the assumption that the measurement information 56 is a normal distribution or a substantially normal distribution. As a result, the peak due to the abnormality of the X-ray thickness measuring device 12 can be detected with higher accuracy.

Specifically, the diagnosis unit 74 calculates the upper limit management limit UCL and the lower limit management limit LCL of the houtts management diagram with the skewness corrected by using the following expressions (2) and (3). In the formulas (2) and (3), the R upper horizontal bar is the average of the variation range of the tube voltage TV, T is an arbitrary value, d is_RIs a Huhart managementThe value of skewness correction of the map (hereinafter referred to as skewness correction value), CL being the center line of the Houtt's chart, σ_RIs the standard deviation of the tube voltage TV, and K (R) is the skewness of the tube voltage TV.

[ formula 2 ]

[ formula 3 ]

Fig. 6 is a diagram showing an example of an R management diagram of tube voltage created by the X-ray thickness measurement system according to the present embodiment. In fig. 6, the vertical axis represents the variation range of the tube voltage TV, and the horizontal axis represents data points that can identify the detection result of the tube voltage TV for each predetermined period.

As shown in fig. 6, the diagnostic unit 74 calculates the upper limit management limit UCL and the lower limit management limit LCL of the R management diagram of the tube voltage TV using the above-described equations (2) and (3). Then, the diagnosis unit 74 detects, as a peak, a tube voltage TV whose variation range exceeds the upper limit management limit UCL or the lower limit management limit LCL, among the tube voltages TV to be detected for the peak.

Next, a specific example of the process of determining the abnormality level of the X-ray thickness measuring device 12 by the diagnosis unit 74 will be described. In the following description, an example will be described in which the diagnosis section 74 determines the abnormality level of the X-ray thickness measurement device 12 based on the detection result of the tube voltage TV, but the abnormality level of the X-ray thickness measurement device 12 is similarly determined for the tube current, the drive voltage, the drive current, and the detection value.

Fig. 7 and 8 are diagrams showing an example of a peak of the tube voltage TV detected by the X-ray thickness measurement system according to the present embodiment. In fig. 7 and 8, the vertical axis represents the variation range of the tube voltage TV, and the horizontal axis represents data points that can identify the detection result of the tube voltage TV for each predetermined period.

The types of spikes of the tube voltage TV are mainly classified into two types. One type is a type in which large spikes are discretely generated, as shown in fig. 7. The other type is a type that continuously generates smaller spikes, as shown in fig. 8. Thus, the abnormality of the X-ray thickness measuring device 12 is represented by both a large peak that is generated discretely and a small peak that is generated continuously.

Therefore, the diagnosis unit 74 determines the abnormality level of the X-ray thickness measurement device 12 based on the product of the frequency of occurrence of the peak of the tube voltage TV and the size of the peak (for example, the variation range of the tube voltage TV). Thus, even when one type of peak among the extremely large peaks that occur discretely and the small peaks that occur continuously occurs is generated in the measurement information 56, the determination of the abnormality level by the X-ray thickness measurement device 12 can reflect the detection results of the two types of peaks. As a result, the accuracy of determining the abnormality level of the X-ray thickness measuring device 12 can be improved.

Fig. 9 is a diagram showing an example of the frequency of occurrence of a peak in tube voltage detected by the X-ray thickness measurement system according to the present embodiment. In fig. 9, the vertical axis represents the frequency of occurrence of a spike in the tube voltage TV per predetermined time (e.g., 1 hour), and the horizontal axis represents the time for detecting a spike in the tube voltage TV.

Fig. 10 is a diagram showing an example of the magnitude of the peak of the tube voltage detected by the X-ray thickness measurement system according to the present embodiment. In fig. 10, the vertical axis represents the magnitude of the peak of the tube voltage TV per predetermined time, and the horizontal axis represents the time for detecting the peak of the tube voltage TV.

The diagnostic unit 74 establishes a flag (hereinafter, referred to as a spike flag) for the detection result of the tube voltage TV whose variation range exceeds the upper limit management limit UCL or the lower limit management limit LCL, among the tube voltage TV to be detected for the spike. Next, as shown in fig. 9, the diagnostic unit 74 calculates the sum of the number of peak marks per predetermined time as the frequency of occurrence of the peak of the tube voltage TV. As shown in fig. 10, the diagnosis unit 74 calculates a detection result of the tube voltage TV in which the peak flag is established (for example, a variation range of the tube voltage TV) as the magnitude of the peak every predetermined time.

Fig. 11 is a diagram showing an example of a calculation result of a product of the generation frequency and the magnitude of the peak of the tube voltage in the X-ray thickness measurement system according to the present embodiment. In fig. 11, the vertical axis represents the product of the frequency and magnitude of occurrence of a peak in the tube voltage TV per predetermined time, and the horizontal axis represents the time for detecting a peak in the tube voltage TV.

As shown in fig. 11, the diagnostic unit 74 calculates the product of the frequency and the magnitude of the peak of the tube voltage TV at every predetermined time as the degree of abnormality of the peak of the tube voltage TV. Then, the diagnosing unit 74 sets the maximum value X of the abnormality degrees at predetermined time intervals to the highest abnormality level. Next, the diagnosis unit 74 classifies the degree of abnormality of the tube voltage TV per predetermined time into a plurality of abnormality levels (for example, four abnormality levels) by the peak hold technique. Thus, the diagnosis unit 74 determines the abnormality level of the X-ray thickness measurement device 12 at predetermined time intervals.

As shown in, for example, table 1 below, the diagnosis unit 74 classifies the peak of the abnormality degree equal to or higher than the maximum value X as the highest abnormality level: 4. as shown in table 1 below, the diagnostic unit 74 classifies peaks of the degree of abnormality of 3 × (maximum value X/4) or more and the maximum value X or less as abnormality levels: 3. as shown in table 1 below, the diagnosis unit 74 classifies peaks of the degree of abnormality of 2 × (maximum value X/4) or more and less than 3 × (maximum value X/4) as abnormality levels: 2. as shown in table 1 below, the diagnosis unit 74 classifies the peak of the abnormality degree having the maximum value X/4 or more and less than 2 × (maximum value X/4) as the abnormality level: 1. then, the diagnosis unit 74 classifies the peak of the abnormality degree smaller than the maximum value X/4 as an abnormality level as shown in table 1 below: 0.

[ TABLE 1 ]

Grade of anomaly	Degree of abnormality
		4	X is less than or equal to the degree of abnormality
3	Degree of abnormality 3X/4. ltoreq<X
		2	Degree of abnormality X/2 ≦<3X/4
1	Degree of abnormality X/4 ≦<X/2
		0	Degree of abnormality 0 ≦ 0<X/4

Fig. 12 is a diagram showing an example of the cumulative sum of the frequencies of occurrence of the spikes of the tube voltage detected by the X-ray thickness measurement system of the present embodiment. In fig. 12, the vertical axis represents the cumulative sum of the frequency of occurrence of the spikes of the tube voltage TV per predetermined time, and the horizontal axis represents the time for detecting the spikes of the tube voltage TV.

Fig. 13 is a diagram showing an example of the sum of the magnitudes of the peaks of the tube voltage detected by the X-ray thickness measurement system according to the present embodiment. In fig. 13, the vertical axis represents the sum of the magnitudes of the spikes of the tube voltage TV per predetermined time, and the horizontal axis represents the time for detecting the spikes of the tube voltage TV.

As shown in fig. 12, the diagnostic unit 74 calculates the cumulative sum of the frequencies of occurrence of the spikes of the tube voltage TV at predetermined time intervals. As shown in fig. 13, the diagnostic unit 74 calculates the cumulative sum of the magnitudes of the tube voltage TV at predetermined time intervals.

Fig. 14 is a diagram showing an example of a calculation result of the cumulative sum of the generation frequencies of the peaks of the tube voltage and the cumulative sum of the magnitudes in the X-ray thickness measurement system according to the present embodiment. In fig. 14, the vertical axis represents the cumulative sum of the frequency of occurrence of the peak of the tube voltage TV per predetermined time and the cumulative sum of the magnitude thereof, and the horizontal axis represents the time at which the peak of the tube voltage TV is detected.

As shown in fig. 14, the diagnostic unit 74 calculates the cumulative sum of the frequency of occurrence of the peak of the tube voltage TV per predetermined time and the cumulative sum of the magnitude of the peak as the degree of abnormality of the peak of the tube voltage TV. Then, the diagnosing unit 74 sets the maximum value of the calculated abnormality degrees to the highest abnormality level. Next, the diagnosis section 74 classifies the degree of abnormality of the tube voltage TV into a plurality of abnormality levels (for example, four abnormality levels) by the peak hold technique.

Fig. 15 is a diagram showing an example of a gradiometer of an abnormality level displayed by the X-ray thickness measurement system of the present embodiment.

As shown in fig. 15, the diagnosis unit 74 causes the display unit 73 to display a gradiometer 1500 indicating the abnormality grade of the X-ray thickness measurement apparatus 12. For example, when the degree of abnormality of the peak of the tube voltage TV is classified into four abnormality levels, the diagnosis unit 74 causes the display unit 73 to display a level meter 1500 capable of displaying the four abnormality levels, as shown in fig. 15.

The diagnostic unit 74 obtains initial measurement information 56 from the prognostic data server 14 until a predetermined time elapses after the activation of the X-ray thickness measurement device 12 (step S1601). Next, the diagnostic unit 74 determines whether or not the acquired measurement information 56 includes the measurement information 56 in the transition period (step S1602).

When the acquired measurement information 56 includes the measurement information 56 during the transition period (yes in step S1602), the diagnostic unit 74 removes the transition period data from the acquired measurement information 56 using the local maximum value or the batch average (step S1603). Then, the diagnostic unit 74 sets the difference between the maximum value and the minimum value of the measurement information 56 from which the transition period data has been removed as the variation range of the measurement information 56 (step S1604). If the acquired measurement information 56 is measurement information 56 outside the transition period (no in step S1602), the diagnostic unit 74 sets the difference between the maximum value and the minimum value of the acquired measurement information 56 as the variation range of the measurement information 56 (step S1604).

Next, the diagnosing unit 74 removes outliers from the variation range of the measurement information report 56 using the IQR or the trimmed mean value (step S1605). Then, the diagnostic unit 74 performs distortion correction on the houtt management map or the R management map of the fluctuation range from which the outliers are removed, and obtains the upper limit management limit UCL and the lower limit management limit LCL of the fluctuation range of the measurement information 56 based on the houtt management map or the R management map from which the distortion correction is performed (step S1606).

The diagnostic unit 74 obtains the measurement information 56 from the prognostic data server 14 after a predetermined time has elapsed since the activation of the X-ray thickness measurement device 12 (step S1701). Next, the diagnosis unit 74 determines whether or not the acquired measurement information 56 includes the measurement information 56 in the transition period (step S1702).

When determining that the acquired measurement information 56 includes measurement information 56 within the transition period (yes in step S1702), the diagnostic unit 74 removes the transition period data from the acquired measurement information 56 using the local maximum value or the batch average (step S1703). Then, the difference between the maximum value and the minimum value of the measurement information 56 from which the transition period data is removed is set as the variation range of the measurement information 56 (step S1704). If the acquired measurement information 56 is measurement information 56 outside the transition period (no in step S1702), the diagnostic unit 74 sets the difference between the maximum value and the minimum value of the acquired measurement information 56 as the variation range of the measurement information 56 (step S1704).

Next, the diagnostic unit 74 compares the variation range of the measurement information 56 with the upper limit management limit UCL and the lower limit management limit LCL (step S1705), and determines whether or not the variation range of the measurement information 56 exceeds the upper limit management limit UCL or the lower limit management limit LCL (step S1706).

Then, the diagnostic unit 74 detects, as a peak, the measurement information 56 whose variation range exceeds the upper limit management limit UCL or the lower limit management limit LCL among the measurement information 56 (step S1707). Then, the diagnostic unit 74 calculates the product of the frequency of occurrence and the size of the peak in the measurement information 56 (the variation range of the measurement information 56) per predetermined time as the degree of abnormality, and determines the abnormality level corresponding to the calculated degree of abnormality as the abnormality level of the X-ray thickness measurement device 12 (step S1708). Then, the diagnosis unit 74 causes the display unit 73 to display a grade meter based on the determination result of the abnormality grade of the X-ray thickness measuring device 12 (step S1709).

As described above, according to the X-ray thickness measurement system of the present embodiment, even when one type of peak among the extremely large peaks that occur discretely and the small peaks that occur continuously occurs in the measurement information 56, the determination of the abnormality level by the X-ray thickness measurement device 12 can be made to reflect the detection results of the two types of peaks. As a result, the accuracy of determining the abnormality level of the X-ray thickness measuring device 12 can be improved.

Although the embodiment of the present invention has been described, the embodiment is provided as an example and is not intended to limit the scope of the invention. The new embodiment can be implemented in other various forms, and various omissions, substitutions, and changes can be made without departing from the spirit of the invention. The embodiments are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Description of the reference numerals

10X-ray thickness measuring system

12X-ray thickness measuring device

14-predictive data server

16 maintenance device

20 measuring part

22X-ray control power supply

24 plate thickness calculating part

26 holding part

28. 37 Transformer

30X-ray generator

32 detector

34 output detection unit

35 resistance

36X-ray tube

38 filament

39a, 39b booster circuit

40 target

42 drive detection unit

44 tube detection part

74 diagnostic part

90 object of measurement

Claims

1. A maintenance device is provided with a diagnostic unit for detecting a peak of measurement information including at least one of the following detection results, determining an abnormality level of an X-ray thickness measurement device for calculating the thickness of a measurement object based on a detection signal based on the product of the frequency of occurrence of the peak and the size of the peak,

the detection result is as follows:

a detection result of a tube voltage between a filament that emits electrons by power from an X-ray control power source and a target that irradiates X-rays on the measurement object having a thickness by collision of electrons emitted from the filament;

a detection result of a tube current flowing between the filament and the target;

a detection result of the detection signal of at least one of a detection voltage and a detection current corresponding to the intensity of the X-ray that has passed through the measurement object;

a detection result of a primary-side drive voltage of a transformer that transforms power from the X-ray control power supply and supplies the transformed power to the filament; and

a detection result of a driving current flowing through a primary side of the transformer.

2. The maintenance device as set forth in claim 1,

the measurement information includes a maximum value and a minimum value of at least one of a detection result of the tube voltage, a detection result of the tube current, a detection result of the detection signal, a detection result of the driving voltage, and a detection result of the driving current,

the diagnostic unit removes transition period data, which is measurement information in a transition period in which the measurement information is changed, from the measurement information, sets a difference between the maximum value and the minimum value included in the measurement information from which the transition period data is removed as a variation range of the measurement information, removes an outlier from the variation range, performs distortion correction on a houtt's chart or an R's chart of the variation range from which the outlier is removed, obtains an upper limit management limit and a lower limit management limit of the variation range based on the houtt's chart or the R's chart subjected to the distortion correction, and detects the measurement information in which the variation range exceeds the upper limit management limit or the lower limit management limit as a spike.

3. The maintenance device as set forth in claim 2,

the diagnostic unit removes the transition period data from the measurement information by using a local maximum value or a batch average.

4. The maintenance device according to claim 2 or 3,

the diagnostic unit removes outliers from the variation range using IQR, which is a four-quadrant distance, until a predetermined period elapses after the X-ray generator having the filament and the target is replaced.

5. The maintenance device as set forth in claim 4,

the diagnostic unit removes outliers from the variation range using a trimmed mean value after the predetermined period has elapsed after the X-ray generator is replaced.