JPH10228310A - Inspection plan supporting device for plant equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To support the settlement of an inspection plan based on the inclination of reduction in reliability by using the inspection data of each plant equipment as a subjective prediction information in a Bayesian reliability analyzing method. SOLUTION: A change process in the application time of probability of normally operating a plant equipment of which inspection is to be planned is stored in a reliability function storing part 11 as a reliability function and a reliability estimation parameter is stored in a reliability estimation parameter storing part 12 as the existence probability of the reliability function. A reliability function correction part 13 calculates the reliability estimation parameter of posterior density from a prior density reliability estimation parameter and inspection data by the use of the Bayesian reliability analyzing method and calculates a corrected reliability function by reflecting the inspection data from the posterior, density reliability inspection parameter. The reliability function and reliability estimation parameter corrected by the correction part 13 are informed of by an information part 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plant equipment inspection plan supporting apparatus for formulating a plant equipment inspection plan.

[0002]

2. Description of the Related Art For example, periodic inspections of power plant equipment are basically carried out at intervals of two or four years. It takes a lot of trouble. It is also necessary to take measures such as temporarily stopping the plant during the inspection period. Therefore, how to reduce the frequency of inspection while ensuring the reliability of the equipment is an issue for cost reduction.
In particular, in recent years, the interval between periodic inspections of power plant equipment has tended to be extended, so inspection plan support equipment for objectively determining inspection times in order to ensure stable operation of plants has been enhanced. Is desired.

[0003] As one method of the inspection plan support, data of past inspections and data of similar plants are analyzed to calculate a probability density function of the life of the equipment, and the inspection is performed based on the possibility of deviating from the reliability section. There is a stochastic method to estimate the time. FIG. 13 is an explanatory diagram of such a conventional stochastic method for estimating an inspection time.

[0004] A characteristic curve S1 in FIG. 13 shows the probability density f (t) of the life of the equipment with respect to the time t elapsed from the start of operation as an actual result in another plant. In addition, a region S2 in FIG. 13 is an integral of a section from time 0 to time a at time t, and is considered to be a probability that the facility cannot be operated continuously due to a failure or the like by time a. In addition, a characteristic curve S3 in FIG. 13 is a reliability at which the equipment can be continuously operated, and is represented by the following equation (1) as a function R (t) of time t.

[0005]

(Equation 1)

The reliability R (t) is compared with a threshold value as needed, and when the reliability R (t) falls below the threshold value, it is determined that the inspection should be performed.

[0007]

However, according to such a conventional method, it is not possible to determine an accurate inspection time when the number of past inspection data is small. In addition, when utilizing data from similar plants, it is difficult to clearly understand the effect of the difference in operating conditions. For example, the probability density f (t) of the characteristic curve S1 in FIG.
Cannot be set in the same manner as the target plant.

In other words, if the probability density f (t) is to be created using only the data of the target plant, if the available data is small, there is a problem that a probabilistically meaningful test cannot be performed. Further, even when the operation of the target plant is accumulated, if there is any occurrence of a defect or an event such as replacement of a new equipment, the probability density f using the actual data obtained from time to time can be obtained by the conventional method. Since the sequential correction technology of (t) has not been developed,
An accurate probability density f (t) cannot be obtained.

Therefore, in recent years, a Bayesian reliability analysis technique has attracted attention as a method for solving the problem.
Equation (1) indicates that the probability of failure during the following minute time dt under the condition that the failure has not occurred until time t is λ.
(T) can be written in the form of dt (Masahiro Ichikawa, Structural Reliability Engineering,
Kaibundo). This λ (t) is called a failure rate, and when these are used to express the equation (1), the following equation (2) is obtained.

[0010]

(Equation 2)

A feature of the Bayesian reliability analysis method is that λ (t) itself is defined as an appropriate random variable based on past experience, and λ (t) is corrected as needed with data obtained thereafter. . By this Bayesian reliability analysis method,
Research has been conducted on a method of predicting the life based on a tendency to decrease the reliability by sequentially correcting the reliability using the data after the start of operation.

However, at present, there is no precedent for an apparatus that formulates an inspection plan by sequentially correcting the reliability as inspection data is accumulated. In particular, in periodic inspections of a large-scale plant such as a power plant with a two-year or four-year cycle, support is provided to determine whether individual equipment should be included in the inspection plan or not to be inspected until the next inspection. There are no examples studied for the purpose.

An object of the present invention is to use an inspection data of an enormous amount of plant equipment constituting a plant as subjective prediction information of a Bayesian reliability analysis method, and to assist in formulating an inspection plan based on a tendency of reliability deterioration. An object of the present invention is to provide an inspection plan support device for plant equipment.

[0014]

According to the first aspect of the present invention, there is provided a reliability function holding unit for holding, as a reliability function, a process of changing a probability that a plant facility to be inspected normally operates with respect to an operation time; A reliability estimation parameter holding unit that holds reliability estimation parameters as the existence probability of the degree function, and a Bayesian reliability analysis method from the reliability estimation parameters of prior density and inspection data held in the reliability estimation parameter holding unit. A reliability function correction unit that calculates a reliability density estimation parameter of the posterior density and calculates a reliability function corrected by reflecting the inspection data from the reliability estimation parameter of the posterior density; and a reliability function correction unit. An inspection plan support device for plant equipment, comprising: a reporting unit that reports a reliability function and a reliability estimation parameter.

According to the first aspect of the present invention, the reliability function holding unit holds, as a reliability function, a process of changing the probability that the plant equipment to be inspected normally operates with respect to the operation time. The holding unit holds the reliability estimation parameter as the existence probability of the reliability function. The reliability function correction unit calculates a post-density reliability estimation parameter using a Bayesian reliability analysis method from the prior density reliability estimation parameter and the inspection data stored in the reliability estimation parameter storage unit, and A reliability function corrected by reflecting the inspection data is calculated from the density reliability estimation parameter. The reliability function and the reliability estimation parameter corrected by the reliability function correction unit are reported by the reporting unit.

According to a second aspect of the present invention, in the first aspect of the present invention, the reliability function correcting unit sets the reliability estimation parameter before inspection stored in the reliability estimation parameter storage unit as an a priori density and the inspection result is abnormal. A reliability estimation parameter calculation that calculates a post-density reliability estimation parameter using the Bayesian reliability analysis method from the number of facilities in the normal state and the number of facilities in the normal state, and updates data stored in the reliability estimation parameter storage unit. And a reliability function calculation means for calculating a reliability function corrected by reflecting the inspection data from the reliability estimation parameter of the posterior density updated by the reliability estimation parameter calculation means. It is a support device.

According to a second aspect of the present invention, in addition to the operation of the first aspect, the reliability estimation parameter calculating means of the reliability function correction unit includes the reliability before inspection stored in the reliability estimation parameter storage unit. Using the estimated parameters as prior densities, the post-density reliability estimation parameters are calculated using the Bayesian reliability analysis method from the number of equipment with abnormal results and normal inspection results, and stored in the reliability estimation parameter storage unit. Update the existing data. The reliability function calculation means of the reliability function correction unit calculates a reliability function corrected by reflecting the inspection data from the reliability estimation parameter of the posterior density updated by the reliability estimation parameter calculation means.

According to a third aspect of the present invention, there is provided the first or second aspect.
In the invention of the above, an inspection time holding unit that holds an inspection time over a period of continuous operation of the plant equipment, and a reliability for calculating a change amount of a reliability function after the inspection time for each inspection time in a time series The change amount calculation unit determines whether or not there is a period in which the numerical value of the reliability change amount exceeds the threshold value. If there is a time when the threshold value is exceeded, the reliability is insufficient in the inspection plan. The inspection plan support device for plant equipment further includes an inspection time validity determination unit that outputs a notification to a notification unit.

According to the third aspect of the present invention, in addition to the operation of the first or second aspect of the present invention, the inspection time holding unit holds the inspection time during the continuous operation of the plant equipment.
The reliability change amount calculation unit calculates the change amount of the reliability function after the inspection time for each inspection time in chronological order, and the inspection time validity determination unit calculates a period during which the numerical value of the reliability change amount exceeds the threshold value. Is determined, and if there is a time when the threshold is exceeded, the fact that the reliability is insufficient in the inspection plan is output to the notification unit.

The invention according to claim 4 is the invention according to claims 1 to 3.
In the invention of the above, the reliability function held in the reliability function holding unit is such that, when the plant equipment is replaced with new equipment, its time axis is corrected so that the equipment replacement time becomes the operation start time. This is an inspection plan support device for plant equipment.

According to the fourth aspect of the present invention, in addition to the operations of the first to third aspects, when the plant equipment is replaced with new equipment, the reliability function stored in the reliability function holding unit is replaced. Correct the time axis so that the equipment replacement time is the operation start time.

According to a fifth aspect of the present invention, there is provided the third or fourth aspect.
In the invention of the above, the inspection time validity determination unit calculates each inspection time so that the reliability change amount is equal to the threshold value,
This is a plant equipment inspection plan support device that reports an inspection time as a longest inspection interval schedule.

According to a fifth aspect of the present invention, in addition to the operation of the third or fourth aspect, the inspection timing validity determining section determines each inspection timing so that the reliability change amount becomes equal to the threshold value. Calculate and report the inspection time as the longest inspection interval schedule.

According to a sixth aspect of the present invention, in the invention of the fifth aspect, the maximum value of the interval between the inspection time and the next inspection time is stored in advance in the inspection time holding unit as the inspection interval maximum limit value. The inspection time validity determination unit is an inspection plan support device for plant equipment that corrects the inspection time to the inspection interval maximum limit value when the calculated inspection time exceeds the inspection interval maximum limit value.

According to the invention of claim 6, in addition to the operation of the invention of claim 5, the maximum value of the interval between the inspection time and the next inspection time is held in the inspection time holding section as the inspection interval maximum side limit value, and the inspection is performed. If the inspection timing calculated by the timing validity determination unit exceeds the maximum inspection interval limit value, the inspection interval is corrected to the maximum inspection interval limit value.

The invention of claim 7 is the invention of claim 3 or 5
In the invention of the above, the inspection time holding unit holds an inspection interval reference value that predetermines a period between the inspection and the next inspection, and the reliability change amount calculation unit sets each inspection time determined by the inspection interval reference value as a starting point. The time series of the reliability change amount calculated, the inspection time validity determination unit determines whether there is a period in which the reliability change amount exceeds the threshold, and if there is a time exceeding the threshold, The inspection plan supporting apparatus for plant equipment is configured to output to the notification unit that the reliability is insufficient in the inspection plan.

According to a seventh aspect of the present invention, in addition to the operation of the third or fifth aspect, the period between the inspection and the next inspection is held in the inspection time holding unit as a single inspection interval reference value,
The reliability change amount calculation unit calculates a time series of the reliability change amount starting from each inspection time determined by the inspection interval reference value, and the inspection time validity determination unit determines that the reliability change amount exceeds the threshold. It is determined whether or not there is a period for performing the inspection, and when there is a time when the threshold is exceeded, it is notified that the reliability is insufficient in the inspection plan.

[0028] The invention of claim 8 is the invention of claims 3 to 7.
In the invention of the above, the reliability change amount calculating unit, when the entire equipment composed of a plurality of parts to be inspected is to be inspected, the reliability function and the reliability estimation parameter according to the characteristics of the component parts and the inspection From the result, the reliability change amount of each component is calculated, the product of the reliability change amount of each component is calculated as the reliability change amount of the entire equipment, and the inspection time validity determination unit is:
An inspection plan support device for plant equipment which outputs to a notification unit that the reliability is insufficient in the inspection plan when there is a time when the reliability change amount of the entire equipment exceeds a threshold.

According to an eighth aspect of the present invention, in addition to the effects of the third to seventh aspects, the entire equipment including a plurality of parts to be inspected is set as an inspection target, and the reliability change amount calculation unit calculates the component parts. Calculate the reliability change amount for each part from the reliability function and reliability estimation parameter and the inspection result according to the characteristics of the components, calculate the product of the reliability change amount of each component as the reliability change amount of the entire equipment, The inspection time validity determination unit reports that the reliability is insufficient in the inspection plan when there is a time when the reliability change amount of the entire facility exceeds the threshold value.

[0030]

Embodiments of the present invention will be described below. FIG. 1 is a block diagram showing a first embodiment of the present invention.

First, the reliability function storage unit 11 stores a reliability function R (t). Reliability function holding unit 11
Then, the process of changing the probability that the equipment to be inspected operates normally with respect to the operation time t is held as a reliability function R (t). In the first embodiment, an accidental failure is targeted. That is, the failure rate λ (t) is set to a constant value λ. The value of λ is given from a small amount of experience in the past. Here, it is defined as a constant value, but is not deterministic, and is a value to be corrected from future inspection data. Here, R (t) in the following equation (3) is held as a reliability function.

R (t) = exp ｛−λ · t｝ (3) t: period from the start of plant operation to the scheduled decommissioning time It should be noted that not the above-mentioned accidental failure but equipment with aging deterioration is targeted. In such a case, for example, the following equation (4) may be adopted as the reliability function.

[0033]

(Equation 3)

Next, the reliability estimation parameter holding unit 12 holds the reliability estimation parameter as the existence probability of the reliability function in accordance with the Bayesian reliability analysis method. That is, the reliability estimation parameter is a probability that λ falls within the range of x ≦ λ ≦ x + dx, and is expressed by the following equation (5).

Pr [x ≦ λ ≦ x + dx] (5) The probability density in equation (5) does not yet reflect the results of future inspection results. When the equation (5) is described as the following equation (6), fλ0 (x) is called a prior density.

Pr [x ≦ λ ≦ x + dx] = fλ0 (x) (6) In the first embodiment, as shown in FIG. 2, the reliability estimation parameter holding unit 12 sets a value indicating a certain density for the time being. To be held.

Next, the reliability function correction unit 13 uses the Bayesian reliability analysis method to determine the reliability of the posterior density from the reliability estimation parameters of the prior density and the inspection data stored in the reliability estimation parameter storage unit 12. An estimation parameter is calculated, and a reliability function corrected by reflecting the inspection data is calculated from the reliability estimation parameter of the posterior density.

First, the reliability estimation parameter calculating means 14 of the reliability function correction unit 13 uses the reliability estimation parameters before inspection stored in the reliability estimation parameter storage unit 12 as prior densities and determines that the inspection result is abnormal. The reliability estimation parameter of the posterior density is calculated using the Bayesian reliability analysis method from the number of facilities and the number of facilities with normal visibility, and the reliability estimation parameter stored in the reliability estimation parameter storage unit 12 is updated. . That is, the posterior density is calculated in accordance with Bayes' theorem, reflecting events that have actually occurred.
Assuming that an event E having a condition of λ has occurred, the posterior density is calculated by the following equation (7).

[0039]

(Equation 4)

In the first embodiment, as an event E, it is assumed that the target facility has been successfully used until t = TI. In this case, the following equation (8) holds. The equation (8) is substituted into the equation (7) to obtain the equation (9).

Pr [E | λ = x] = exp {−x · T1} (8) fλ1 (x) = T1 · exp {−T1 · x} (9) Reliable calculation result by equation (9) It is stored in the degree estimation parameter. FIG. 3 shows the shapes of fλ0 (x) and fλ1 (x).
In the first embodiment, since no failure has occurred for a certain period, the numerical value of the region where the failure rate x is small in the posterior distribution fλ1 (x) is corrected to be higher than that in the prior distribution fλ0 (x). .

Next, the reliability function calculating means 15 calculates a reliability function reflecting the inspection data from the reliability estimation parameter of the posterior density. Now, let p be the value calculated by the following equation (10).

[0043]

(Equation 5)

Here, the larger the λ is, the smaller the reliability is. Therefore, the reliability R1 is calculated using λp0 determined by the above equation (10).
When (t) is obtained, Expression (11) is obtained.

R1 (t) = exp ｛−λp0 · t｝ (11) Then, the probability that the true reliability R (t) is smaller than R1 (t) is determined by the following equation (12). Become.

Pr [R1 (t) ≧ R (t)] = Pr [λ ≧ λp0] = p (12) That is, Expression (12) shows the reliability of the prior reliability. As a result, the posterior λp1 with respect to λp0 in equation (10)
Is changed from the expression (9) to the expression (13), and the lower limit R1 (t) of the reliability which is the expression (14) is determined.

Λp1 = −logp / T1 (13) R1 (t) = exp {(logp / T1) · t} (14) That is, the true reliability R (t) is equal to or more than R1 (t). In particular, it has the confidence of (1-p). This R1
(T) The value is stored in the reliability function storage unit 11. Notification section 1
At 6, the modified reliability function and the reliability estimation parameter are reported.

Although the first embodiment deals with the case where no failure has occurred for a certain period of time, the same procedure can be used in the following cases, for example. (1) In the case where inspection data of other similar equipment can be used If Expression (3) is placed as Expression (15), it can be handled similarly. ki is a parameter that takes into account differences in the shape and the like of each facility. As a result, equation (8) is replaced with equation (16), and equation (7) is replaced with equation (17).

[0049]

(Equation 6)

That is, T1 in the equation (8) is merely replaced with ΣTi, and the operation progress of one facility and the operation progress of several similar facilities can be given the same effect. (2) Case where Damage Record can be Used It is sufficient to consider a case where data indicating that any one of i = 1 to m in the above equation (15) is actually damaged is obtained. Here, it is assumed that the equipment with i = 1 is damaged at t = T1, and the other equipment is safe up to t = Ti (j = 2, 3,..., M). In that case, the expression (16) is expressed by the following (1)
Since equation (8) is obtained, equation (17) becomes equation (19). If a uniform distribution is considered as the prior density, Equation (20) is obtained.

[0051]

(Equation 7)

The shapes of equations (20) and (17) are shown in comparison with FIG. Compared to the posterior distribution S11 of the equation (17) reflecting the result of no failure for a certain period, the posterior distribution S12 of the equation (20) experiencing the failure has a higher numerical value in a region where the failure rate x is large. . As in this example, the expression (2)
By using the method of calculating the reliability with 0) as the reliability parameter, the data at the time of failure can be reflected in the reliability.

As described above, according to the inspection facility support system for plant equipment in the first embodiment of the present invention, even if the data based on the inspection results in a new plant is small, the subjectivity based on the experience in another plant or the like is obtained. By holding a reliable reliability function and reliability estimation parameters, it is possible to support an inspection plan. Further, it is possible to improve the accuracy sequentially by correcting the reliability function and the reliability estimation parameter as the performance data on the presence or absence of a failure due to inspection or the like is obtained. In addition, it is possible to improve accuracy by utilizing data from similar plants.

Next, a second embodiment of the present invention will be described. FIG. 5 is a block diagram showing a second embodiment of the present invention. The second embodiment is different from the first embodiment shown in FIG. 1 in that an inspection time holding unit 17 that holds an inspection time over a period of continuous operation of plant equipment,
A reliability change amount calculation unit 18 for calculating a change amount of the reliability function after the inspection time in time series for each inspection time, and whether or not there is a period in which the value of the reliability change amount exceeds the threshold value In addition, if there is a time when the threshold value is exceeded, the inspection plan is additionally provided with an inspection time validity determination unit 19 that reports that reliability is insufficient in the inspection plan. Thereby, it is possible to determine whether or not the numerical value of the reliability is equal to or more than the threshold value at the scheduled inspection time. Other configurations are the same as those of the first embodiment shown in FIG. 1, and therefore, the same components are denoted by the same reference symbols and description thereof will be omitted.

First, as in the case of the first embodiment,
Based on the inspection data, a reliability function R such as equation (11)
1 (t) is obtained. On the other hand, the inspection time holding unit 17 includes:
As shown in FIG. 6, the inspection time is held during the period of continuous operation of the equipment. The reliability change amount calculation unit 18
Then, for each inspection time of the inspection time holding unit 17,
The amount of change in the reliability function R1 (t) after these inspection times is calculated in time series.

FIG. 7 shows a calculation example in that case. As shown in FIG. 7, the reliability function R1 (t) after reflecting the inspection data.
From the characteristic curve S1, the reliability change amount after each inspection time at each of the first inspection, the second inspection, and the third inspection after the start of operation is obtained. That is, the amount of change in reliability after the first inspection time is calculated as ΔR1, the amount of change in reliability after the second inspection time is calculated as ΔR2, and the amount of change in reliability after the third inspection time is calculated as ΔR3.

Next, the inspection time validity judgment section 19 judges whether or not there is a period in which the numerical value of the reliability change amount ΔR exceeds the threshold value ΔRr. Outputs to the notification unit 16 that the reliability is insufficient in the inspection plan.

As described above, according to the inspection facility support system for plant equipment according to the second embodiment of the present invention, not the reliability itself but the reliability change amount ΔR within the inspection period is determined. Since the index is used, it is possible to operate the inspection to restore the reliability.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 8 is an explanatory diagram of the reliability function stored in the reliability function storage unit 11 according to the third embodiment of the present invention. This third embodiment is different from the first embodiment shown in FIG. 1 or the second embodiment shown in FIG. 5 in that the reliability function is held when the plant equipment is replaced with new equipment. The time axis of the reliability function R1 (t) held in the unit 11 is modified so that the equipment replacement time becomes the operation start time.

In FIG. 8, it is assumed that the reliability function holding unit 11 holds a characteristic curve S11 as a reliability function R1 (t). At the time points T1, T2, and T3 after the operation of the plant according to the inspection plan, the change amounts of the reliability function (characteristic curve S1) are calculated as ΔR1, ΔR2, and ΔR3 by the reliability change amount calculation unit 18.

Here, at time T3, the reliability function R1
It is assumed that the plant equipment has been replaced with new equipment due to a decrease in (t) or the like. In this case, in the third embodiment, the reliability function (characteristic curve S1 ′) with the time T3 as the operation time is stored in the reliability function holding unit 11.
After the time point T4, the reliability change amounts ΔR1 ′ and ΔR2 ′ are calculated using the updated reliability function (characteristic curve S1 ′).

As described above, according to the inspection facility support system for plant equipment in the third embodiment of the present invention, the time axis of the reliability function is corrected so that the equipment replacement time becomes the operation start time. Therefore, it is possible to avoid an excessive inspection plan equivalent to that of the old equipment and to formulate an inspection plan reflecting the reliability of the new equipment.

Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 9 is an explanatory diagram of an inspection timing determination function in the inspection timing validity determination unit 19 according to the fourth embodiment of the present invention. In the fourth embodiment, the inspection timing is determined by the inspection timing validity determination unit 19 of the second embodiment shown in FIG. 5 when the reliability change amount ΔR falls below a certain value. A plan was developed.

In FIG. 9, a characteristic curve S1 is a reliability function R1 (t) held by the reliability function holding unit 11,
Inspection time validity determination section 19 sets each inspection time T such that reliability change amount ΔR becomes equal to threshold value ΔRr.
1. Calculate T2 and T3. That is, the reliability change amounts ΔR1, ΔR at the respective inspection times T1, T2, T3.
2. All of ΔR3 should be equal to the threshold value ΔRr. Inspection times T1, T in the fourth embodiment
2, T3 becomes the longest inspection interval schedule as a result, and the notification unit 16 is output to that effect and notified to the operator.

As described above, according to the inspection facility support system for plant equipment according to the fourth embodiment of the present invention, the maximum inspection interval at which reliability is guaranteed can be grasped, and a smooth inspection plan can be obtained. Can be considered.

Next, a fifth embodiment of the present invention will be described. FIG. 10 is an explanatory diagram of an inspection timing determination function in the inspection timing validity determination unit 19 according to the fifth embodiment of the present invention. In the fifth embodiment, even when the reliability change amount ΔR is small in the fourth embodiment, the inspection interval maximum limit value ΔTmax is predetermined so that the inspection time can be determined within a certain period. The inspection interval is set so as not to exceed the inspection interval maximum limit value ΔTmax.

The inspection time holding unit 17 holds an inspection interval maximum limit value ΔTmax, which means the maximum value of the interval between the inspection time and the next inspection time, in advance. ΔT in FIG.
max corresponds to the inspection interval maximum limit value. In the case where the inspection time validity determination unit 19 determines that the inspection time calculated from the characteristic curve S1 of the reliability function R1 (t) and the threshold value ΔRr of the reliability change amount exceeds the inspection interval maximum limit value ΔTmax. , The inspection interval is the inspection interval maximum limit value ΔTma
Correct to x. In the fifth embodiment, T1 in FIG. 10, which is the first inspection time, exceeds ΔTmax. Therefore, T1 is corrected to T1 ′, which is equivalent to ΔTmax. T2 and T3, which are inspection times after the second time, are T
1 ′ is regarded as the first inspection time, and is sequentially calculated.

As described above, according to the inspection support system for plant equipment in the fifth embodiment of the present invention, the inspection time is determined within a certain period even when the reliability change amount is small. Therefore, even when a cause of deterioration due to a sudden factor that cannot be predicted from the Bayesian reliability analysis method can occur, an inspection plan can be secured at a minimum cycle.

Next, a sixth embodiment of the present invention will be described. FIG. 11 is an explanatory diagram of an inspection time validity determining function of the inspection time validity determining unit 19 according to the sixth embodiment of the present invention. This sixth embodiment is different from the second embodiment shown in FIG.
In the case where a periodic inspection period is determined by the inspection time validity determination unit 19 according to the embodiment, when the length of the inspection period is determined, whether the reliability change amount exceeds a threshold value is determined. This is to evaluate the validity of the inspection period.

The inspection time holding unit 17 previously holds the inspection interval reference value ΔTc in FIG. This inspection interval reference value ΔTc is only one inspection interval reference value that determines the period between the inspection and the next inspection. Reliability change amount calculator 18
Then, the time series ΔR1, ΔR2, and ΔR3 of the reliability change amount starting from each inspection time (T1, T2, T3 in the figure) determined by the inspection interval reference value ΔTc are calculated. In the inspection time validity determination unit 19, the reliability change amounts ΔR1, ΔR2, ΔR3
Is compared with the threshold value ΔRr, and it is determined whether or not there is a period in which the threshold value ΔRr is exceeded. If there is a time in which the threshold value ΔRr is exceeded, the fact that the reliability is insufficient in the inspection plan is reported. .

As described above, according to the inspection facility support system for plant equipment according to the sixth embodiment of the present invention, when a periodic inspection period is determined, the periodic inspection period is determined based on the reliability change amount. Thus, the validity of the inspection period can be evaluated.

Next, a seventh embodiment of the present invention will be described. FIG. 12 is a functional explanatory view of the seventh embodiment of the present invention, and shows a case where an inspection plan is formulated from the reliability change amount when the entire equipment composed of a plurality of parts to be inspected is to be inspected. Things.

The seventh embodiment is applied, for example, to the case where the pipes constituting the pipe are individually connected in series. In this case, if any of the pipes becomes defective, the entire pipe will not function. Therefore, in the seventh embodiment, the product of the reliability of the individual pipes constituting the pipeline is treated as the reliability of the entire pipeline.

The reliability change amount calculating section 18 obtains the reliability of each component from the reliability function and the reliability estimation parameter corresponding to the characteristic of the component and the inspection result as shown by the characteristic curves S1, S2 and S3 in FIG. Degree change ΔR11, ΔR12, ΔR
13 is calculated, and the product ΔR11 of the reliability change amount of each component part is calculated.
Calculate ΔR12 and ΔR13 as the reliability change amount ΔR of the entire equipment. The inspection time validity determination unit 19 reports that the reliability is insufficient in the inspection plan when there is a time when the reliability change amount of the entire equipment exceeds the threshold value ΔRr.

As described above, according to the inspection facility support system for plant equipment according to the seventh embodiment of the present invention, when the entire equipment composed of a plurality of parts to be inspected is to be inspected, Also, the validity of the inspection period can be evaluated based on the reliability change amount.

[0076]

As described above, according to the present invention, the inspection data of a huge amount of plant equipment constituting a plant is used as subjective prediction information of a Bayesian reliability analysis method, and the reliability tends to decrease. An inspection plan support device for plant equipment that supports the preparation of an inspection plan based on the inspection plan is realized.

That is, by applying the Bayesian reliability analysis method, even when the data used as a material for determining the inspection time is small, it is possible to make up for the lack of data by subjective prediction and to check the inspection data. The accuracy of analysis can be improved stepwise with the accumulation of data. Therefore, it is possible to appropriately support the inspection plan.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a prior density held in a reliability estimation parameter holding unit according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram of a pre-density and a post-density stored in a reliability estimation parameter storage according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram of a posterior density reflecting failure data held in a reliability estimation parameter holding unit according to the first embodiment of the present invention.

FIG. 5 is a block diagram showing a second embodiment of the present invention.

FIG. 6 is an explanatory diagram of an inspection time held by an inspection time holding unit according to the second embodiment of the present invention.

FIG. 7 is an explanatory diagram of a reliability change amount calculated by a reliability change amount calculation unit according to the second embodiment of the present invention.

FIG. 8 is an explanatory diagram of a reliability function held in a reliability function holding unit according to the third embodiment of the present invention.

FIG. 9 is an explanatory diagram of an inspection timing determination function in an inspection timing validity determination unit according to a fourth embodiment of the present invention.

FIG. 10 is an explanatory diagram of an inspection time determination function in an inspection time validity determination unit according to a fifth embodiment of the present invention.

FIG. 11 is an explanatory diagram of an inspection time validity determining function in an inspection time validity determining unit according to a sixth embodiment of the present invention.

FIG. 12 is an explanatory diagram of functions according to a seventh embodiment of the present invention.

FIG. 13 is an explanatory diagram of an inspection time estimation method based on a reliability section according to the related art.

[Explanation of symbols]

 11 reliability function holding unit 12 reliability estimation parameter holding unit 13 reliability function correction unit 14 reliability estimation parameter calculation unit 15 reliability function calculation unit 16 reporting unit 17 inspection time storage unit 18 reliability change amount calculation unit 19 inspection time Validity judgment unit

Claims (8)

[Claims] 1. A reliability function holding unit that holds a process of changing a probability that a plant facility to be inspected normally operates with respect to an operation time as a reliability function, and a reliability estimation parameter as an existence probability of the reliability function. A reliability estimation parameter holding unit that holds the reliability estimation parameter of the posterior density using a Bayesian reliability analysis method from the reliability estimation parameter of the prior density and the inspection data held in the reliability estimation parameter holding unit. A reliability function correction unit that calculates and calculates a reliability function corrected by reflecting the inspection data from the reliability estimation parameter of the posterior density; and a reliability function and a reliability estimation parameter corrected by the reliability function correction unit. And a notifying unit for notifying the inspection report. 2. The reliability function correction unit according to claim 1, wherein said reliability estimation parameter before inspection stored in said reliability estimation parameter storage unit is used as a prior density to determine the number of facilities whose inspection results are abnormal and of normal. A reliability estimation parameter calculation means for calculating a reliability estimation parameter of the posterior density using a Bayesian reliability analysis method from the data and updating data held in the reliability estimation parameter holding unit; and calculating the reliability estimation parameter. 2. A reliability function calculating means for calculating a reliability function corrected by reflecting inspection data from the reliability estimation parameter of the posterior density updated by means. Inspection plan support equipment for plant equipment. 3. An inspection time holding unit for holding an inspection time during a period of continuous operation of the plant equipment, and for each inspection time, a change amount of a reliability function after the inspection time is calculated in a time series. The reliability change amount calculating unit determines whether or not there is a period in which the numerical value of the reliability change amount exceeds the threshold, and if there is a time when the value exceeds the threshold, the reliability is determined in the inspection plan. The inspection plan support device for plant equipment according to claim 1 or 2, further comprising an inspection time validity determining unit that outputs a shortage to the notification unit. 4. The reliability function stored in the reliability function storage unit is modified such that when the plant equipment is replaced with new equipment, the time axis thereof is changed so that the equipment replacement time becomes the operation start time. The inspection plan supporting apparatus for plant equipment according to claim 1, wherein the inspection plan supporting apparatus is configured to perform the inspection. 5. The inspection time validity determination unit calculates each inspection time so that the reliability change amount becomes equal to a threshold value, and reports the inspection time as a longest inspection interval schedule. 3. The method according to claim 3, wherein
An inspection plan support device for plant equipment according to (1). 6. The inspection time holding unit previously holds a maximum value of an interval between an inspection time and a next inspection time as an inspection interval maximum limit value, and the inspection time validity determining unit calculates The inspection plan support of the plant equipment according to claim 5, wherein when the checked inspection time exceeds the inspection interval maximum limit value, the inspection time is corrected to the inspection interval maximum limit value. apparatus. 7. The inspection time holding unit holds an inspection interval reference value that determines a period between an inspection and the next inspection in advance, and the reliability change amount calculation unit performs each inspection determined by the inspection interval reference value. The time series of the reliability change amount starting from the timing is calculated, and the inspection time validity determination unit determines whether there is a period in which the reliability change amount exceeds the threshold value and determines whether the reliability change amount exceeds the threshold value. The inspection plan support device for plant equipment according to claim 3 or 5, wherein when the inspection plan exists, the fact that the reliability is insufficient in the inspection plan is output to the notification unit. 8. The reliability change amount calculating section, when making a whole equipment composed of a plurality of parts to be inspected an inspection object, a reliability function and a reliability estimation according to the characteristics of the component parts. The reliability change amount for each component is calculated from the parameters and the inspection results, and the product of the reliability change amount for each component is calculated as the reliability change amount for the entire equipment. 8. The system according to claim 3, wherein when there is a time when the entire reliability change amount exceeds the threshold value, the fact that the reliability is insufficient in the inspection plan is output to the notification unit. An inspection plan support device for the plant equipment described in the above.