The present invention relates to an analyzing device, a diagnostic method, and a program for diagnosing a state of a pipeline.
In developed countries, aging degradation of public facilities is a social problem. For example, pipeline networks which transport resources such as water, oil, and gas include many in use beyond service lives thereof, and an accident such as a fluid leakage and a pipeline rupture, being caused by degradation of the pipeline networks, has become a problem. For the purpose of preventing an occurrence of such an accident, an operator visually inspects an exterior appearance of such a pipeline. However, since an inner surface of an actual pipeline is sometimes corroded, it is necessary to perform diagnosis in consideration of not only an exterior appearance of the pipeline but also a state of an inside thereof.
PTL 1 discloses a method of measuring a thickness of a pipeline in a plant for nuclear power generation, thermal power generation or the like. In the method of PTL 1, an active sensor is used, in which an electromagnetic oscillator that sweeps and outputs an inside of a predetermined frequency band and an optical fiber sensor that detects a dynamic distortion of an object being measured are integrated with each other. Moreover, in the method of PTL 1, the active sensor is attached to a pipeline, an ultrasonic wave or a vibration designated at a predetermined frequency of more than 0 to 10 megahertz is input in a thickness direction of the pipeline, and a reflected wave of the input ultrasonic wave or vibration or a composite wave thereof is detected.
PTL 2 discloses an inspection method of inspecting a state of degradation of an embedded pipeline. In the method of PTL 2, a correlation relationship between parameters and impact elastic wave test data is acquired in advance, in which the parameters are acquired from a force-deformation relationship indicating a relationship between a force applied to a test pipe from outside and deformation of the test pipe being caused by the force, and the impact elastic wave test data are acquired by performing an impact elastic wave test on the test pipe. In the method of PTL 2, based on the correlation relationship between the parameters acquired from the force-deformation relationship and the impact elastic wave test data, impact elastic wave measurement data of a pipe being inspected, being actually measured by the impact elastic wave test, are evaluated, and a degree of deterioration of the pipe being inspected is determined quantitatively.
[PTL 1] Japanese Unexamined Patent Application Publication No. 2010-071741
[PTL 2] Japanese Unexamined Patent Application Publication No. 2006-038598
According to the method of PTL 1, a thickness of the object being measured is measured based on a detected resonance of an ultrasonic wave or a vibration signal, being generated by the pipeline, whereby a thickness reduction or corrosion of the pipeline can be inspected. However, in the method of PTL 1, since a material property of the pipeline is not taken into consideration, there has been a problem that an actual state of degradation of the pipeline cannot be acquired accurately.
According to the method of PTL 2, a degree of deterioration of the pipe being inspected can be inspected with high accuracy without being affected by an embedding environment. Incidentally, in the method of PTL 2, the degree of deterioration of the pipe being inspected is determined based on a correlation relationship between the parameters acquired from the force-deformation relationship acquired in advance and the impact elastic wave measurement data of the pipe being inspected. In other words, in the method of PTL 2, since the degree of deterioration of the pipe being inspected is determined by using the parameters acquired indirectly from the force-deformation relationship, there is a problem that diagnostic accuracy is not sufficient.
An object of the present invention is to provide an analyzing device capable of solving the above-mentioned problems and estimating a state of degradation of the pipeline with sufficient diagnostic accuracy.
An analyzing device according to one aspect of the present invention includes: material property calculating means for calculating a material property of a pipeline being inspected, based on measurement information including a load applied to the pipeline being inspected and a displacement associated with a load applied to the pipeline being inspected; and a degree-of-deterioration calculating unit for calculating a degree of deterioration of the pipeline being inspected, based on the material property of the pipeline being inspected, the material property being calculated by a material property calculating unit.
A diagnostic method according to one aspect of the present invention includes: calculating a material property of a pipeline being inspected, based on measurement information including a load applied to the pipeline being inspected and a displacement associated with a load applied to the pipeline being inspected; and calculating a degree of deterioration of the pipeline being inspected, based on the calculated material property of the pipeline being inspected.
A program according to one aspect of the present invention causes a computer to execute: processing of calculating a material property of a pipeline being inspected, based on measurement information including a load applied to the pipeline being inspected and a displacement associated with a load applied to the pipeline being inspected; and processing of calculating a degree of deterioration of the pipeline being inspected, based on the calculated material property of the pipeline being inspected.
According to the present invention, a diagnosis system for estimating a state of degradation of a pipeline with sufficient diagnostic accuracy is able to be provided.
Hereinafter, example embodiments of the present invention will be described with reference to the drawings. The example embodiments to be described below are subjected to technically preferable limitations in order to embody the present invention, but do not limit the scope of the invention to the following. In all the drawings for use in describing the following example embodiments, the same reference numerals are assigned to similar spots unless there is a specific reason. In the following example embodiments, repeated descriptions of similar configurations/operations may be omitted. Orientations of arrows in the drawings are merely examples, and do not limit orientations of signals between blocks.
First, a diagnosis system according to a first example embodiment of the present invention will be described with reference to the drawings.
As in
The material property calculating unit 11 (also called a material property calculating means) acquires measurement information regarding the material property of the pipeline 100 from the measuring device 30. The material property calculating unit 11 calculates the material property of the pipeline 100, based on the measurement information acquired from the measuring device 30. In other words, the material property calculating unit 11 calculates the material property of the pipeline 100, based on measurement information including a load applied to the pipeline 100 being inspected and a displacement associated with the load applied to the pipeline 100. The material property calculating unit 11 outputs the calculated material property of the pipeline 100 to the degree-of-deterioration calculating unit 12.
The degree-of-deterioration calculating unit 12 (also called a degree-of-deterioration calculating means) acquires the material property of the pipeline 100 from the material property calculating unit 11. The degree-of-deterioration calculating unit 12 compares the acquired material property of the pipeline 100 with a material property of the pipeline 100 in a normal state, and calculates a degree of deterioration of the pipeline 100, based on a difference between the material properties. In other words, the degree-of-deterioration calculating unit 12 calculates the degree of deterioration of the pipeline 100 based on the material property of the pipeline 100, which is calculated by the material property calculating unit 11.
For example, the degree of deterioration of the pipeline 100 calculated by the degree-of-deterioration calculating unit 12 is transmitted to an external system and a display device. The degree of deterioration transmitted to the external system and the display device is provided as display information to an administrator who manages the pipeline 100, and the like.
The measuring device 30 includes a load measuring instrument 31 and a displacement measuring instrument 32. The load measuring instrument 31 measures the load applied to the pipeline 100. The displacement measuring instrument 32 measures the displacement of the pipeline 100. The measuring device 30 transmits, to the analyzing device 10, load information regarding the load measured by the load measuring instrument 31 and displacement information regarding the displacement of the pipeline 100, which is measured by the displacement measuring instrument 32.
As described above, the diagnosis system of the present example embodiment calculates the degree of deterioration of the pipeline being inspected, which includes the material property. Therefore, the diagnosis system of the present example embodiment can calculate the state of degradation of the pipeline with sufficient diagnostic accuracy.
Next, a diagnosis system of a second example embodiment of the present invention will be described with reference to the drawings.
As in
The material property calculating unit 21 acquires load information applied to a pipeline 100 being inspected and the displacement information of the pipeline 100. The material property calculating unit 21 calculates the material property of the pipeline 100 by using the acquired load information and displacement information. The material property calculating unit 21 outputs the calculated material property of the pipeline 100 to the pipe rigidity variable estimating unit 22.
For example, the material property calculating unit 21 acquires, from the measuring device 30, a pressure generated by a fluid that flows through the inside of the pipeline 100 or an earth pressure from embedding soil as the load information. The material property calculating unit 21 may acquire, from the measuring device 30, a pressure artificially applied to the pipeline 100 as the load information.
One example of a method for acquiring load information and displacement information of the pipeline 100 will be described with reference to the drawings.
For example, in the cross-sectional view of
A method for calculating the material property by the material property calculating unit 21 will be described by taking an example.
The radial displacement w of the pipe made of a uniform material and having a uniform thickness, the radial displacement w occurring when the load P is applied from both sides of the pipe as illustrated in
When Equation 1 is represented in the form of the Hooke's law, and the moment of inertia of area is represented as I, pipe rigidity K can be defined by the following Equation 2. The pipe rigidity K at the circumferential position θ can be determined by the elastic modulus E, thickness t, and radius R of the pipeline 100.
Generally, as in a thickness t(θ) and an elastic modulus E(θ), the thickness t and the elastic modulus E can be represented as functions of the circumferential position θ of the pipe. When the number of measurement points is one, an average thickness tave and an elastic modulus Eave are acquired by using a measured value of the pipe rigidity K. In contrast, when the number of measurement points is plural, a thickness te(θ) and an elastic modulus Ee(θ), which are estimated values of spatial distributions of pipe rigidity variables, are acquired by using measured values of the pipe rigidity K and a pipe rigidity model 221.
For example, when the pipeline 100 is locally degraded within a range of circumferential positions θ1 to θ2 as in
The pipe rigidity variable estimating unit 22 estimates the pipe rigidity variables of the pipeline 100 by using the material property of the pipeline 100, which is calculated by the material property calculating unit 21. For example, the pipe rigidity variable estimating unit 22 refers to premeasured pipe rigidity variables of the time when the pipeline 100 is normal, applies the pipe rigidity variables, which are referred to, to the pipe rigidity model 221, and estimates the estimated values of the pipe rigidity variables. The pipe rigidity variable estimating unit 22 includes the pipe rigidity model 221 and a curve fitting unit 222. The curve fitting refers to acquiring a curve that fits experimentally acquired data or limiting condition in the best way.
The pipe rigidity model 221 can be expressed as K(θ|θα, Θβ) as functions of the circumferential position θ where the load P is applied, a pipe rigidity variable θα of the healthy portion 110, a pipe rigidity variable θβ of the degraded portion 120, an estimated value Θβ of the pipe rigidity variable, and the circumferential positions θ1 and θ2 of the degraded portion 120. The pipe rigidity variable θα of the healthy portion 110, the pipe rigidity variable θβ of the degraded portion 120, and the estimated value Op of the pipe rigidity variable include parameters indicated in square brackets of the following Equations 3 to 5, respectively.
θα=[Eα,tα,R] (3)
θβ=[Eβ,tβ,R] (4)
θβ=[θβ,θ1,θ2] (5)
For example, the pipe rigidity model 221 can be calculated by defining a trial function as acos θ and by using Equation 6 from a radial displacement acquired by the Rayleigh method. A parameter f on the right side of Equation 6 is acquired by Equation 7. As the pipe rigidity variable θα of the healthy portion, a value described in a specification drawing needs only to be stored in a pipe information storage unit 51.
The curve fitting unit 222 estimates an estimated value Θeβ of a pipe rigidity variable in which an error between a pipe rigidity calculated by using the load and the displacement, which are included in the measurement information of the pipeline 100, and a pipe rigidity calculated by using the pipe rigidity model 221 becomes minimum. For example, by using a pipe rigidity Kexp(θ) calculated from measured values and the pipe rigidity model K(θ|θα,Θβ), the curve fitting unit 222 acquires the circumferential positions θ1 and θ2 of the degraded portion, which satisfy the following Equation 8, and an estimated value Θeβ of the pipe rigidity variable.
For example, by using a nonlinear optimization method such as the Levenberg-Marquardt method, the curve fitting unit 222 acquires the circumferential positions θ1 and θ2 of the degraded portion and the estimated value Θeβ of the pipe rigidity variable.
For the pipeline 100 including the degraded portion 120 in
The curve fitting unit 222 acquires the circumferential positions θ1 and θ2 of the degraded portion 120 and the estimated value θeβ of the pipe rigidity variable in such a way that an error between the pipe rigidity Kexp(θ) calculated by using the loads and the displacements and the circumferential direction dependency of the pipe rigidity, which is calculated by using the pipe rigidity model K(θ|θα,Θβ), becomes minimum.
The tensile strength estimating unit 23 estimates a tensile strength of the pipeline 100 by using the pipe rigidity variable estimated by the pipe rigidity variable estimating unit 22. In other words, the tensile strength estimating unit 23 refers to a strength information storage unit 52, and estimates the tensile strength of the pipeline 100 based on a correlation relationship between a tensile strength and the pipe rigidity variable θβ acquired in advance by using a test pipe. For example, as in
The degree-of-deterioration calculating unit 24 calculates the degree of deterioration of the pipeline 100 by using the tensile strength estimated by the tensile strength estimating unit 23. For example, by using the following Equation 9, the degree-of-deterioration calculating unit 24 calculates, as a degree of deterioration Ld, a difference between a calculated tensile strength 62 and a tensile strength Gi of a normal state. The degree-of-deterioration calculating unit 24 may calculate, as the degree of deterioration Ld, change rates of the calculated tensile strength σ2 and the tensile strength σ1 of a normal state, and the like.
L
dβσ2−σ1 (9)
The storage device 50 includes the pipe information storage unit 51 and the strength information storage unit 52.
In the pipe information storage unit 51, the pipe rigidity variable θα of the healthy portion 110, which is based on a design specification and the like, is stored. The pipe information storage unit 51 is referred to at the time when the pipe rigidity variable estimating unit 22 creates the pipe rigidity model 221.
In the strength information storage unit 52, the correlation relationship between the tensile strength and the pipe rigidity variable θβ acquired in advance by using the test pipe is stored. The strength information storage unit 52 is referred to at the time when the tensile strength estimating unit 23 estimates the tensile strength σmax from the estimated value Θβ of the pipe rigidity variable.
The above is the description of the configuration of the diagnosis system 1 of the present example embodiment. Subsequently, a diagnostic method of the pipeline being inspected, which is performed by the diagnosis system 2, will be described with reference to the drawings.
First, the diagnosis system 2 applies a load P to the pipeline 100, and measures the displacement w of the pipeline 100, which is caused by the application of the load P (step S11). For example, the diagnosis system 2 applies the load P while changing the circumferential position θ of the pipeline 100, and measures the displacement w of the pipeline 100, which is associated with the load P.
Next, the diagnosis system 2 calculates the pipe rigidity Kexp(θ) by using the load P and the displacement w, which are measured at every circumferential position θ (step S12).
Next, the diagnosis system 2 performs curve fitting for the pipe rigidity Kexp(θ) and the pipe rigidity model K(θ|θα, θβ), thereby acquiring the circumferential position (θ1, θ2) of the degraded portion 120 and the estimated value θβ of the pipe rigidity variable (step S13). At the time of creating the pipe rigidity model 221, the diagnosis system 2 refers to the pipe rigidity variable θα of the healthy portion 110, which is stored in the pipe information storage unit 51.
Next, the diagnosis system 2 estimates the tensile strength σmax by using the estimated value Θβ of the pipe rigidity variable of the degraded portion 120 and the correlation relationship between the pipe rigidity variable and the tensile strength which is stored in the strength information storage unit 52 (step S14).
Then, the diagnosis system 2 calculates the degree of deterioration La by using the estimated tensile strength σmax (step S15).
The above is the description of the diagnostic method of the pipeline being inspected, which is performed by the diagnosis system 2 along the flowchart of
In a general diagnostic method of the state of degradation of the pipeline, an exterior appearance of the pipeline is visually inspected. The state of degradation of the pipeline also appears on a change of the thickness in the pipeline and a change of the material property such as the elastic modulus. Therefore, only the visual inspection is not sufficient for the diagnosis of the pipeline.
The thickness of the pipeline may also be acquired by the method disclosed in PTL 1 (Japanese Unexamined Patent Application Publication No. 2010-071741), however information regarding the material property such as the elastic modulus cannot be acquired by such method. For example, when the change rate of the thickness is 0%, and the change rate of the elastic modulus is −30%, it is estimated that the pipeline is degraded from the change rate of the elastic modulus. However, in the method of PTL 1, since the state of degradation of the pipeline is determined by only the change rate of the thickness of the pipeline, it is erroneously determined that the pipeline is normal.
Meanwhile, the method of the present example embodiment enables estimating the thickness and elastic modulus of the degraded portion of the pipeline by using the pipe rigidity model and the spatial distribution of the pipe rigidity acquired from the load and the displacement which are applied to the pipeline. Therefore, the method of the present example embodiment enables correctly grasping the state of degradation of the pipeline.
As described above, the method of the present example embodiment enables correctly diagnosing the state of degradation of the pipeline by using the spatial distribution of the pipe rigidity calculated based on the measurement information of the load and the displacement which are applied to the pipeline.
A computer 90 in
As in
The processor 91 develops a program, which is stored in the auxiliary storage device 93 or the like, in the main storage device 92, and executes the developed program. In the present example embodiment, a configuration of using a software program installed in the computer 90 may be adopted. The processor 91 executes processing performed by the diagnosis system according to the present example embodiment.
The main storage device 92 has a region in which the program is developed. The main storage device 92 may be, for example, a volatile memory such as a dynamic random access memory (DRAM). A nonvolatile memory such as magnetoresistive random access memory (MRAM) may be configured and/or added as the main storage device 92.
The auxiliary storage device 93 stores a variety of data. The auxiliary storage device 93 is composed of hard disk or a local disk such as a flash memory. If possible, a configuration in which a variety of data are stored in the main storage device 92 is adopted, and the auxiliary storage device 93 may be omitted.
The input/output interface 95 is an interface for connecting the computer 90 and peripherals to each other. The communication interface 96 is an interface for connecting to an external system or device through a network such as the Internet and an intranet based on a standard or a specification. The input/output interface 95 and the communication interface 96 may be integrated with each other as an interface that connects to an external instrument.
The computer 90 may be configured in such a way that input instruments such as a keyboard, a mouse, and a touch panel are connected thereto according to needs. These input instruments are used for inputting information and setting. When a touch panel is used as the input instrument, a configuration in which a display screen of a display instrument also serves as an interface of the input instrument may be adopted. Data communication between the processor 91 and the input instrument may be relayed by the input/output interface 95.
The computer 90 may be equipped with a display instrument for displaying information. When the computer 90 is equipped with the display instrument, it is preferable that the computer 90 be provided with a display control device (not shown) for controlling display of the display instrument. The display instrument may be connected to the computer 90 via the input/output interface 95.
Moreover, the computer 90 may be equipped with a disk drive according to needs. For example, the disk drive is connected to the bus 99. The disk drive relays reading of data/program from a recording medium (program recording medium, not shown), writing of a processing result of the computer 90 to the recording medium, and the like between the processor 91 and the recording medium. For example, the recording medium can be achieved by an optical recording medium such as a compact disc (CD) and a digital versatile disc (DVD). The recording medium may be achieved by s semiconductor recording medium such as a universal serial bus (USB) memory and a secure digital (SD) card, a magnetic recording medium such as a flexible disk, and recording mediums according to other systems.
The above is one example of a hardware configuration for enabling the diagnosis system according to each of the example embodiments of the present invention. The hardware configuration of
Components of the diagnosis system of each of the example embodiments can be randomly combined with one another. The components of the diagnosis system of each of the example embodiments may be achieved by software, or may be achieved by circuits.
The block diagrams and the conceptual diagrams used in the description of each of the example embodiments illustrate not a hardware-unit configuration but functional-unit blocks. In these drawings, each of the components is described to be achieved by one instrument; however, an achieving means thereof is not limited to such a single instrument. That is, these components may be configured to be physically divided, or may be configured to be logically divided.
While the invention has been particularly shown and described with reference to exemplary embodiments thereof, the invention is not limited to these embodiments. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the claims.
This application is based upon and claims the benefit of priority from Japanese patent application No. 2017-240475 filed on Dec. 15, 2017, the disclosure of which is incorporated herein in its entirety by reference.
Number | Date | Country | Kind |
---|---|---|---|
2017-240475 | Dec 2017 | JP | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/JP2018/045203 | 12/10/2018 | WO | 00 |