JP2023045226A - pressure detection system - Google Patents

Abstract

To provide a pressure detection system with which it is possible to detect a pressure of a plurality of portions to be measured, easily and suppressing errors.SOLUTION: A pressure detection system 21 comprises pressure sensors 23a-23h, a reference sensor 24, a gas sending unit 27, a flow channel control unit 28, and an acquisition arithmetic unit 29. The reference sensor 24 serves as a reference for calibration that is used in calibrating the pressure sensors 23a-23h that measure a pressure of the portions to be measured. The gas sending unit 27 sends a gas to the reference sensor 24 and the pressure sensors 23a-23h, respectively, and the flow channel control unit 28 controls on/off of sending a gas to the pressure sensors 23a-23h and the reference sensor 24. The acquisition arithmetic unit 29 calibrates the pressure sensors 23a-23h on the basis of a pressurized pressure value having been pressurized by the gas and detected by the reference sensor 24 and the pressure sensors 23a-23h and a non-pressurized pressure value having been depressurized and detected by the reference sensor 24 and the pressure sensors 23a-23h.SELECTED DRAWING: Figure 2

Description

The present invention relates to pressure sensing systems.

For example, in dams, pumping pressure (uplift pressure) is measured to monitor the safety of the dam. The pumping pressure is measured by installing pressure gauges connected to each of the plurality of drainage holes provided in the inspection gallery of the dam body.

In order to measure the pumping pressure, it is necessary to open and close multiple valves on the pipe that connects the drain hole and the pressure gauge. It requires a great deal of time and effort.

Bourdon tube type pressure gauges, for example, are often used as pressure gauges for measuring pumping pressure. In the case of the Bourdon tube type pressure gauge, since measurement is performed by reading a needle indicating the detected pressure, errors are likely to occur depending on the operator who reads the needle. Therefore, there is a method of detecting the pumping pressure using a pressure sensor, but each pressure sensor has an error, and the error of the pressure sensor also fluctuates over time.

Patent Document 1 describes a method of providing a chamber pressure sensor in each of a plurality of chambers and calibrating the chamber pressure sensor in order to detect the pressure of each of the plurality of chambers with the pressure sensor. The method includes delivering gas to a plurality of chambers, wherein a difference between a pressure measurement of a selected chamber pressure sensor equal to an average of a plurality of first pressure measurements and an average of a plurality of second pressure measurements is performed. Perform a calibration of the selected chamber pressure sensor to eliminate

JP 2020-148473 A

However, since the technique of US Pat. No. 6,000,002 sends gas to multiple chambers, it cannot be applied to narrow areas such as drain holes in inspection galleries. In addition, the method of Patent Document 1 needs to obtain the average value of the plurality of first pressure measurement values and the plurality of second pressure measurement values, respectively, which complicates the calibration process.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a pressure detection system that can easily detect the pressures of a plurality of measured parts while suppressing errors.

A pressure detection system of the present invention includes a plurality of pressure sensors, a reference sensor, a gas delivery section, a gas delivery control section, and a calibration calculation section. A plurality of pressure sensors respectively measure the pressures of the plurality of measured portions. The reference sensor provides the calibration reference used to calibrate the pressure sensor. The gas delivery unit delivers gas to each of the reference sensor and the pressure sensor to be calibrated. The gas feed controller controls on and off of the gas feed to the plurality of pressure sensors and the reference sensor. The calibration calculation unit calculates the pressurized pressure values detected by the reference sensor and the pressure sensor in the state of being pressurized to the respective target pressure values by the gas, and the reference sensor and the pressure sensor in the state of releasing the pressurization by the gas. calibrate the pressure sensor based on the unpressurized pressure value detected by and;

Preferably, the pressure detection system includes a general controller that controls the gas feed control section and the calibration calculation section.

It is preferable that the reference sensor and each of the plurality of pressure sensors are connected in parallel to the gas delivery section through a guide tube that guides the gas. More preferably, the guide tube has a main line extending from the gas delivery section and a plurality of pressure sensor lines, one end of which connects to the main line and the other end of which connects to a pressure sensor. , a tube to be measured, a branch tube to be measured, a first valve, a second valve, and a third valve. The tube to be measured has one end connected to the pressure sensor line and the other end connected to the part to be measured. The part-to-be-measured branch pipe branches from the part-to-be-measured pipe and has an open end. The first valve is provided closer to the part to be measured than the branch position of the part to be measured branched from the part to be measured. The second valve is provided on the branch pipe of the part to be measured. The third valve is provided on the main line side of the pressure sensor line with respect to the connection position where the tube to be measured is connected.

The pressure sensing system preferably comprises a first delivery valve and a second delivery valve, a delivery branch and a branch valve. The first delivery valve and the second delivery valve are provided in series with each other in a guide pipe between the gas delivery section and the reference sensor and the plurality of pressure sensors, and direct from the gas delivery section to the reference sensor and the plurality of pressure sensors. Switch gas delivery on and off. The delivery section branch pipe branches from the guide pipe between the first delivery valve and the second delivery valve and has an open tip. A branch valve is arranged in the delivery section branch pipe.

The calibration calculation unit associates the pressurized pressure of the pressure sensor with the pressurized pressure of the reference sensor to determine the maximum detectable pressure, and associates the nonpressurized pressure of the reference sensor with the nonpressurized pressure of the pressure sensor to determine the minimum detectable pressure. It is preferable to calibrate the pressure sensor by:

ADVANTAGE OF THE INVENTION According to this invention, the pressure of several to-be-measured parts can be detected simply, suppressing an error.

It is explanatory drawing about the installation position of each part of a dam bank body and a pressure detection system. 1 is a configuration diagram of a pressure detection system; FIG. FIG. 4 is a flow diagram of pumping pressure measurement in the pressure sensing system;

An embodiment of the present invention will be described by taking as an example a pressure detection system for detecting the pumping pressure of a dam of a hydroelectric power station. The pressure detection system can detect pressure at multiple locations. Pressure sensing systems are not limited to measuring the pumping pressure of dams, for example, the pressure of oil and natural gas flowing through pipeline channels, the inside of pipes and tanks at natural gas drilling sites. pressure, pressure inside pipes, tanks and distillation towers in petroleum plants, and pressure inside fermentation tanks in sake production. is suitable for

The dam body 13 is provided with a plurality of drain holes 14a to 14h spaced apart in the direction in which the inspection gallery 18 extends. One end of each of the drain holes 14a to 14h is open to the ground (bedrock) 17 under the dam body 13, and the other end is open to the inspection corridor 18. As shown in FIG. The pressure detection system includes a plurality of pressure sensors for detecting the pumping pressure, and the pressure sensors are provided in connection with the openings of the drain holes 14a to 14h on the inspection corridor 18 side. As a result, the pumping pressure at each location on the dam body 13 is detected. The detected pumping pressure is transmitted to an external controller provided in the administration building 19 that manages the dam via a general controller (to be described later) provided in the inspection corridor 18 . Thus, according to the pressure detection system, the management building 19 is notified of the detected pumping pressure. In the following description, the drain holes 14a to 14h are referred to as drain holes 14 when they are not distinguished from each other.

In the example shown in FIG. 1, the number of pressure sensors is eight because the pressure sensing system is provided at a dam having eight drainage holes 14 . However, the number of pressure sensors may be appropriately set according to the number of detection points for detecting pumping pressure. In FIG. 1, the installation positions of the pressure sensors are denoted by PSa to PSh, the installation positions of the general controller are denoted by PC, and the installation positions of the calibration units used for calibrating the individual pressure sensors are denoted by PU. . The installation position of the calibration unit is not particularly limited, but the calibration unit of this example is equipped with a reference sensor for calibrating the pressure sensor, and the reference sensor is located at a position where the influence of the atmospheric pressure and its fluctuations is minimized. It is arranged at the lowest position in the corridor 18. In this example shown in FIG. 1, the administrative building 19 is provided at a height substantially equal to the top end 13u of the dam body 13, but the position of the administrative building 19 varies depending on the dam.

2, the pressure detection system 21 calibrate the pressure sensors 23a, 23b, 23c, . It is for measuring. The pressure detection system 21 includes pressure sensors 23a, 23b, 23c, . a portion 29; The pressure detection system 21 preferably further includes a general controller 31 and an external controller 32, which is also the case in this example.

Each of the pressure sensors 23 a to 23 h and the reference sensor 24 is connected to the acquisition calculation section 29 by, for example, an optical cable, and outputs the detected pressure to the acquisition calculation section 29 . The acquisition calculation unit 29 acquires the detected pressure values from the pressure sensors 23 a to 23 h and the reference sensor 24 , and performs predetermined processing such as calibration of the pressure sensors 23 a to 23 h and output to the general controller 31 . The first to ninth valves V1 to V9 and the The gas delivery section 27 is controlled by a flow path control section 28 connected by, for example, an optical cable. The general controller 31 centrally controls the flow path control section 28 and the acquisition calculation section 29 . The external controller 32 is connected to the general controller 31 by, for example, an optical cable, and appropriately issues various control instructions to the general controller 31 . The general controller 31 is provided with an input section 35, and the external controller 32 is provided with an input section 36, respectively. and so on. The overall controller 31 is provided with a display section 37, and the external controller 32 is provided with a display section 38, respectively. The pressure detection value and the like detected from 1 to 23h are displayed. Display images are generated by the general controller 31 and the external controller 32, respectively. Each part of the pressure detection system 21 will be described in detail below.

The pressure sensor 23a is for detecting the pressure in the drain hole 14a (the pressure of water or gas coming out of the drain hole 14a) as pumping pressure. constitutes Similarly, the pressure sensors 23b-23h are for detecting the pressure in the drain holes 14b-14h as pumping pressure. The pressure sensors 23b to 23h also constitute detection units SUb to SUh together with first to third valves V1 to V3 which are the same as the first to third valves V1 to V3 of the detection unit SUa. However, since each of the detection units SUb to SUh has the same configuration as the detection unit SUa, the illustration of the first to third valves V1 to V3 is omitted.

The pressure sensors 23a to 23h of this example detect the pumping pressure, which is the pressure of the water in the drain hole 14, as the pressure of the part to be measured. It can be detected as pressure. The pressure sensors 23a to 23h of this example are pressure sensors that detect so-called gauge pressures based on the atmospheric pressure. Further, the pressure sensors 23a to 23h in this example are semiconductor pressure sensors (semiconductor diaphragm pressure sensors), but other pressure sensors such as strain gauge pressure sensors and thin film pressure sensors may be used. However, it is preferable that the plurality of pressure sensors 23a to 23h are the same pressure sensors and have the same range (measuring range). In this example, a high precision compact pressure transmitter FP201 manufactured by Yokogawa Electric Corporation is used as the pressure sensors 23a to 23h. The pressure sensors 23 a to 23 h output the detected pressure values to the acquisition calculation section 29 .

The reference sensor 24 is a pressure sensor that serves as a calibration reference used to calibrate each of the pressure sensors 23a to 23h. Since the reference sensor 24 is a pressure sensor that serves as a calibration reference, it is preferable that the error is as small as possible and the pressure can be precisely detected. By using such a reference sensor 24, the pressure sensors 23a to 23h are precisely calibrated by the reference sensor 24 and then detect the pressure. It works fine without it. Therefore, if pressure sensors are already provided in the drain holes 14, those pressure sensors may be used as the pressure sensors 23a to 23h.

The reference sensor 24 is a pressure sensor that detects gauge pressure like the pressure sensor. The pressure sensor used for the reference sensor 24 preferably has the same range as the pressure sensors 23a to 23h, and preferably has a higher accuracy than the pressure sensors 23a to 23h by an order of magnitude or more and is of high quality. The reference sensor 24 in this example is a semiconductor pressure sensor (semiconductor diaphragm type pressure sensor), but like the pressure sensors 23a to 23h, other pressure sensors such as strain gauge type pressure sensors and thin film type pressure sensors may be used. may be used. In this example, as the reference sensor 24, a pressure transmitter EJX430J manufactured by Yokogawa Electric Corporation is used. The reference sensor 24 constitutes a calibration unit CU together with the gas delivery section 27 and the fourth to ninth valves V4 to V9, etc., and outputs the detected pressure detection value to the acquisition calculation section 29. FIG.

The gas delivery section 27, which constitutes the calibration unit CU together with the reference sensor 24, pressurizes the reference sensor 24 and the pressure sensors 23a to 23h when calibrating the pressure sensors 23a to 23h. The gas delivery unit 27 delivers air (air) as an example of gas used for pressurization (pressurized gas) to the reference sensor 24 and the pressure sensors 23a to 23h. The gas sending unit 27, the reference sensor 24 and the pressure sensors 23a to 23h are connected by a guide pipe TA for guiding air. It is guided to each of the sensors 23a-23h.

The gas delivery section 27 has a compressor 41 , an air filter 42 and a regulator 43 . The compressor 41 compresses the taken-in air to increase the pressure and sends it out under the control of the flow path control unit 28 . The air filter 42 cleans the air sent from the compressor 41 by removing dust. Although the air filter 42 may be omitted, it is preferable to have it in order to prevent dust from entering valves and devices on the downstream side in the air feeding direction. The regulator 43 is arranged downstream of the air filter 42 in the air feeding direction, and performs pressure regulation to reduce the pressure of the air from the compressor 41 . Compressor 41, air filter 42, and regulator 43 may be formed integrally. Instead of the compressor 41, a blower, a fan, or another blower that blows air at a pressure lower than that of the compressor 41 may be used. good.

The compressor 41 in this example is a so-called air compressor that pressurizes and delivers the taken air, but it may be a compressor that pressurizes and delivers a gas other than air. Gases other than air include, for example, inert gases such as nitrogen and rare gases (helium, argon, etc.). Alternatively, the compressor 41 may be replaced by a cylinder or the like capable of compressing and containing the above gases other than air and adjusting the delivery flow rate.

The gas delivery unit 27 is connected to each of the reference sensor 24 and the pressure sensors 23a to 23h and a guide pipe TA that guides the air delivered from the compressor 41. As shown in FIG. As a result, the air sent from the compressor 41 is reliably sent to the reference sensor 24 and the pressure sensors 23a to 23h without waste, and is also quickly sent because it is guided in a space of a very small volume called a pipe. , to quickly proceed to the calibration process.

The reference sensor 24 and each of the pressure sensors 23a to 23h are preferably connected in parallel to the gas delivery section 27 by a guide tube TA, and this embodiment also does so. The guide tube TA includes a main line TAm extending from the compressor 41, and a reference sensor line TAr and a plurality of pressure sensor lines TAs each having one end connected to the main line TAm. The pressure sensor lines TAs are provided for each of the pressure sensors 23a to 23h, and eight lines in this example. The position where the reference sensor line TAr and the main line TAm are connected is defined as a connection position P21, and the position where the pressure sensor line TAs and the main line TAm are connected is defined as a connection position P22.

A fourth valve V4 and a fifth valve V5 are provided in series on the main line TAm between the gas delivery unit 27 and the reference sensor 24 and the pressure sensors 23a to 23h. The upstream side in the sending direction of the air from the portion 27 is the fourth valve V4, and the downstream side is the fifth valve V5. The fourth valve V4 and the fifth valve V5 are a first delivery valve and a second delivery valve for switching ON (delivery) and OFF (non-delivery) of delivery of air toward the reference sensor 24 and the pressure sensors 23a to 23h. It is an example of a delivery valve, and opens and closes the main line TAm under the control of the flow path control unit 28 . The fourth valve V4 and the fifth valve V5 are electromagnetic valves in this example.

From the main line TAm between the fourth valve V4 and the fifth valve V5, a delivery portion branch pipe TB with an open tip branches off, and the branched position is defined as a branch position P23. A sixth valve V6 is arranged in the delivery section branch pipe TB, and the sixth valve V6 opens and closes the delivery section branch pipe TB under the control of the flow path control section . While air is being delivered from the gas delivery portion 27, the entire amount of air is guided to the reference sensor 24 and the pressure sensors 23a to 23h if the sixth valve V6 is closed. While the delivery of air from the gas delivery part 27 is off, if the sixth valve V6 is open, the secondary side of the compressor 41 is opened, the residual pressure is released, and the pressure is returned to the atmospheric pressure. By closing the sixth valve V6, the main line becomes airtight.

A seventh valve V7 for adjusting the degree of opening of the main line TAm is preferably provided between the gas delivery section 27 and the fourth valve V4, and this is also the case in this example. The seventh valve V7 is for adjusting the flow rate of air from the gas delivery section 27. As shown in FIG. The seventh valve V7 is not particularly limited as long as it can adjust the degree of opening of the main line TAm, and is a manual needle valve in this example.

It is preferable that an eighth valve V8 for adjusting the opening degree of the delivery section branch tube TB is provided on the distal end side of the delivery section branch tube TB from the sixth valve V6. there is The eighth valve V8 is for adjusting the speed of releasing the residual pressure in the compressor 41 as described above. The eighth valve V8 is not particularly limited as long as it can adjust the opening of the delivery section branch pipe TB, and in this example, it is a manual needle valve.

It is preferable that the reference sensor line TAr is provided with a ninth valve V9 for opening and closing the reference sensor line TAr, and this example also does so. The ninth valve V9 closes the reference sensor line TAr and separates it from the main line TAm when inspecting the reference sensor 24 (inspection for maintenance, etc.) and when calibrating the pressure sensor 23. be. The ninth valve V9 is not particularly limited as long as it can open and close the reference sensor line TAr, and is a manual valve in this example.

In the detection unit SUa, each pressure sensor line TAs extending from the main line TAm to the pressure sensor 23a is provided with a third valve V3. The third valve V3 is for switching ON and OFF of the delivery of air to the pressure sensor 23a, and opens and closes the pressure sensor line TAs under the control of the flow path control section 28.

In the detection unit SUa, there are a tube to be measured TC, one end of which is connected to the pressure sensor line TAs and the other end of which is connected to the drain hole 14a, and a branch tube of the part to be measured, which branches off from the tube to be measured TC and has an open end. TD is provided. The position where the tube to be measured TC and the pressure sensor line TAs are connected is defined as a connection position P24, and the position where the branch tube TD of the tube to be measured TC is branched is defined as a branch position P25. The third valve V3 is provided on the main line TAm side of the pressure sensor line TAs with respect to the connection position P24.

A first valve V1 is provided on the drain hole 14a side of the branch position P25 of the tube to be measured TC. The first valve V1 opens and closes the tube to be measured TC under the control of the flow path control section .

A second valve V2 is provided in the branch pipe TD to be measured. The second valve V2 opens and closes the measurement target branch pipe TD under the control of the flow path control section .

Also in the detection units SUb-SUh, the pressure sensor lines TAs, the tube to be measured TC, the branch tube to be measured TD, and the first to third valves V1 to V3 are provided in the same configuration. In this example, V3 is an electromagnetic valve, and V1 and V2 are motor valves.

The flow path control section 28 is an example of a gas feed control section that controls feeding of air from the gas feed section 27 to each of the reference sensor 24 and the pressure sensors 23a to 23h. Under the control of the general controller 31, the flow path control unit 28 switches the reference sensor 24 and the pressure sensors 23a to 23h into a pressurized state in which target pressure values are detected and a non-pressurized state in which the pressurized state is released. Controls the opening and closing of the first to sixth valves V1 to V6 at a predetermined timing so that air flow paths for each are formed, and turns on and off the compressor 41 of the gas delivery unit 27. and to control air delivery. The flow path control unit 28 also opens and closes the first to third valves V1 to V3 at a predetermined timing under the control of the general controller 31, thereby connecting the pressure sensor line TAs on the side of the inspection corridor 18 with respect to the drain hole 14. The pipe to be measured TC and the branch pipe to be measured TD are opened and closed to form a guide path for water from the drain hole 14 .

The acquisition calculation unit 29 is an acquisition unit that acquires the detected pressure values of the pressures detected by the reference sensor 24 and the pressure sensors 23a to 23h, and is an example of a calibration calculation unit that calibrates the pressure sensors based on the detected pressure values. be. For example, when calibrating the pressure sensors 23a to 23h, the acquisition calculation unit 29 detects the non-pressurized pressure values detected by the reference sensor 24 and the pressure sensors 23a to 23h in the non-pressurized state (hereinafter referred to as and a detected pressure value of the pressurized pressure detected by the reference sensor 24 and the pressure sensors 23a to 23h in the pressurized state (hereinafter referred to as the pressurized pressure value) are inputted. The pressure sensors 23a to 23h are calibrated based on the pressure value and the applied pressure value. The reference sensor 24 and the pressure sensors 23a to 23h in this example output a detection current corresponding to the detected pressure. is output to the acquisition calculation unit 29 as. The acquisition calculation unit 29 associates the non-pressurized pressure value of each of the pressure sensors 23a to 23h with the non-pressurized pressure value of the reference sensor 24, and defines this non-pressurized pressure value as the minimum detected pressure (zero point), The applied pressure value of each of the pressure sensors 23a to 23h is associated with the applied pressure value of the reference sensor 24, and this applied pressure value is set as the maximum detected pressure. Then, the acquisition calculation unit 29 performs calculations for adjusting the difference between the maximum detected pressure and the minimum detected pressure for each of the pressure sensors 23a to 23h to each range. The pressure sensors 23a to 23h are calibrated in this manner, and the detected pressure values before calibration and the detected pressure values after calibration are associated with each other and stored in a storage unit (not shown). Note that the reference sensor 24 and the pressure sensors 23a to 23h may output the detected voltage corresponding to the detected pressure to the acquisition calculation unit 29 as the detected pressure value such as the pressurized pressure value and the non-pressurized pressure value.

Further, when measuring the pumping pressure, when the detection pressure values are input from the pressure sensors 23a to 23h, the acquisition calculation unit 29 specifies the detection pressure values before calibration stored in the storage unit. Then, the detected pressure value after calibration associated with the specified detected pressure value is output to the general controller 31 as the pumping pressure value. The acquisition calculation unit 29 has a time counter, and outputs the detected pressure value to the general controller 31 in association with the date and time when the detected pressure value is input.

The general controller 31 controls the flow path control section 28 and the acquisition calculation section 29 based on a preset sequence. The sequence and the execution timing of the sequence may be set in advance as an application program, or may be set by the input unit 35 . The application program may be installed in the overall controller 31 or in the external controller 32 in addition to or instead of the overall controller 31 . When incorporated only in the external controller 32, the general controller 31 functions under the control of the external controller 32 and causes each part to execute the sequence. Also, when it is incorporated only in the external controller 32 , the timing of executing the sequence may be set by the input unit 36 .

The general controller 31 receives images (input images) for setting a sequence or the like by the input unit 35, states of each unit of the pressure detection system 21, and various types of pressure detection values input from the reference sensor 24 and the pressure sensors 23a to 23h. It is possible to generate various display images such as data images that display data and the like, and display them on the display unit. The general controller 31 may also include a storage unit (not shown) that stores the past pressure detection values input from the pressure sensors 23a to 23h together with the date and time of input as history data. there is Then, the overall controller 31 of the present example generates a list display image displaying these history data in a list (list) and a graph display image by graphing the history data as chronological data, and generates the list display image and the graph display image. can be displayed on the display unit 37.

The overall controller 31 of this example is connected to the external controller 32 . Thus, the overall controller 31 is configured to be able to output to the external controller 32 the input states and various data of each part of the pressure detection system 21 , generated data of various display images, and the like. Therefore, when an instruction to transmit these data is input from the external controller 32 to the general controller 31, the data are transmitted from the general controller 31 to the external controller 32 based on this transmission instruction, and displayed on the display unit 37. be able to. The transmission instruction is input to the external controller 32 by an input operation on the input unit 36, for example.

The operation of the above configuration will be explained. In the steady state of the pressure detection system 21, the first to third valves V1 to V3 are open, the fourth to sixth valves V4 to V6 are closed, and the compressor 41 of the gas delivery unit 27 is turned off. be made. Depending on the state of each valve described above, one end of the drain hole 14 on the side of the inspection corridor 18 is in an open state, and water is discharged. The pumping pressure measurement and the calibration process for calibrating the pressure sensors 23a to 23h are performed under the control of the general controller 31 arranged in the inspection hall 18 or the external controller 32 arranged in the administration building 19. FIG. In this way, the pressure sensing system 21 eliminates the need for an operator to calibrate and sense the pumping pressure at each of the plurality of drain holes 14 in the inspection gallery 18 .

When measuring the pumping pressure, the pressure detection system 21 performs calibration processing of the pressure sensors 23a to 23h before detecting the pumping pressure. However, the timing of performing the calibration process may be appropriately set by the general controller 31 or the external controller 32 . For example, it may be set to be performed each time the pumping pressure is detected, or may be set to be performed at predetermined time intervals such as every month, every two weeks, or every second, or The input unit 35 or the input unit 36 may be set so as to perform at a desired timing. In this example, the reference sensor 24 and the pressure sensors 23a to 23h each output a detected pressure value to the acquisition calculation unit 29 at predetermined time intervals.

When calibrating the pressure sensors 23a to 23h before detecting the pumping pressure, the flow path control unit 28 first opens the fourth to sixth valves V4 to V6 as shown in FIG. After that (S1), the acquisition calculation unit 29 stores the detected pressure values (S2) acquired from each of the reference sensor 24 and the pressure sensors 23a to 23h as non-pressurized pressure values in the storage unit.

Next, the flow path control unit 28 closes the first, second, and sixth valves V1, V2, and V6 (S3), and then turns on the driving of the compressor 41 (S4) to supply air. Delivery is started to pressurize the reference sensor 24 and the pressure sensors 23a-23h. The target pressure value is detected by the reference sensor 24, and the acquisition calculation unit 29 determines whether or not the pressure values detected by the reference sensor 24 and the pressure sensors 23a to 23h are stable (S5). When it is determined that the pressure is stable, it continues pressurization by feeding air. When receiving this affirmative determination result, the flow path control unit 28 closes the fifth valve V5 (S6) to make the guide tube TA airtight.

The flow path control unit 28 turns off the driving of the compressor 41 (S7) and opens the sixth valve V6 (S8). Note that the order of S7 and S8 may be reversed. The acquisition calculation unit 29 then stores the detected pressure values (S9) acquired from each of the reference sensor 24 and the pressure sensors 23a to 23h as applied pressure values in the storage unit. Then, the acquisition calculation unit 29 performs calibration processing for each of the pressure sensors 23a to 23h based on the non-pressurized pressure value and the pressurized pressure value stored in the storage unit (S10). For example, when the non-pressurized pressure value of the reference sensor 24 is acquired as 0 kPa and the non-pressurized pressure value of the pressure sensor 23a is acquired as a pressure value of 0.1 kPa, the non-pressurized pressure value of the pressure sensor 23a is used as the reference. The minimum detection pressure is calibrated to 0 kPa according to the non-pressurized pressure value of the sensor 24 . Similarly, the pressure sensors 23b to 23h are also calibrated to match the non-pressurized pressure value of the reference sensor 24 to 0 kPa. Further, the calibration of the pressurized pressure value is calibration of the maximum detected pressure value (full scale value) when pressurized to the maximum pressure in each of the above steps S4, S5, S6, S7, and S8. For example, when the reference sensor 24 and the pressure sensor 23a having a full scale value of 300 kPa are used, the target pressure value is set to 300 kPa and the reference sensor 24 is pressurized in step S4. Similarly, when the applied pressure value of the pressure sensors 23a to 23h pressurized is obtained as 285 kPa, the applied pressure value is adjusted to the applied pressure value of the reference sensor 24 and calibrated as the maximum detected pressure of 300 kPa. do. That is, the pressure sensor 23a is calibrated from a range of 0.1 kPa to 285 kPa to a range of 0 kPa to 300 kPa. Similarly, the pressure sensors 23b to 23h are also calibrated to match the applied pressure value of the reference sensor 24 to 300 kPa.

The acquisition calculation unit 29 calibrates the pressure sensors 23a to 23h based on the applied pressure values and the non-pressurized pressure values detected by the reference sensor 24 and the pressure sensors 23a to 23h, and calculates the applied pressure values and the non-pressurized pressure values. The supply of air to the reference sensor 24 and the pressure sensors 23a to 23h for obtaining pressure values is switched on and off under the control of the general controller 31. FIG. This eliminates the need for the operator to open and close the valves of the pressure sensors 23a to 23h of the inspection corridor 18 for calibration during the calibration process, which is simple. In addition, since the detected pressure values from the pressure sensors 23a to 23h are sent to the general controller 31 and the external controller 32 via the acquisition calculation unit 29, the pressurized pressure value, the non-pressurized pressure value, and the pumping pressure are respectively The installation position PC in the inspection gallery 18 or the administration building 19 is notified. Therefore, the detection result of the pumping pressure can be known without working in the inspection gallery 18, and detection errors caused by needle reading as in the case of using a Bourdon tube type pressure gauge or the like are prevented. be. Furthermore, since the pressure sensors 23a to 23h are calibrated to detect the pumping pressure, errors are suppressed. Further, if the pressurization pressure value of the reference sensor 24 is set to the maximum pressure value detected by the reference sensor 24 at the time of calibration, the control of the pressurization of the reference sensor 24 by air will maximize the pressure of the reference sensor 24. Since it is only necessary to pressurize, there is no need to precisely control the flow rate of air delivery, which is simple.

Further, since the reference sensor 24 and each of the pressure sensors 23a to 23h are connected in parallel to the gas delivery section 27 by the guide pipe TA, the reference sensor 24 and each of the pressure sensors 23a to 23h are connected to the compressor. When the air from 41 is sent in, they are pressurized to equal pressures. Further, when calibrating only some of the pressure sensors 23a to 23h, air can be calibrated by sending air to only that part, and compared to the case of sending air to all the pressure sensors 23a to 23h, The part can be quickly pressurized to the same pressure as the reference sensor 24 .

Since the pressure detection system is provided with the fourth to sixth valves V4 to V6, the secondary side of the gas delivery section 27 is protected from sudden pressure changes, and the reference sensor 24 and the pressure sensors 23a to 23h are pressurized and Pressurization can be quickly released. Further, since the fourth to sixth valves V4 to V6 are unitized together with the reference sensor 24 and the gas delivery section 27 to constitute the calibration unit CU, the operator does not move around in the inspection corridor 18, and the reference sensor Inspection and maintenance of the reference sensor 24 can be performed in the vicinity of 24 together with the fourth to sixth valves V4 to V6.

After the calibration process (S10), the flow path control unit 28 closes the fourth valve V4 (S11) to protect the compressor 41, and then opens the fifth valve V5 (S12). In step S12, it is more preferable to gradually reduce the pressure of the guide tube TA by setting the degree of opening of the fifth valve V5 to an open state smaller than the full opening. In that case, the flow path control unit 28 can control the opening of the valve V5. Subsequently, abnormality determination is performed by measuring the difference between the reference sensor 24 and the pressure sensors 23a to 23h (S13). The abnormality determination in step S13 can be performed, for example, as follows. First, after step S12, the reference sensor 24 detects that the pressure in the guide tube TA has reached approximately 3/4, 2/4, and 1/4 of the maximum pressure. A pressure value is detected at each of 23a to 23h. Then, the pressure value detected by the reference sensor 24 is compared with the pressure value detected by each of the pressure sensors 23a to 23h, and the error between the reference sensor 24 and the pressure sensors 23a to 23h is a threshold value (1 in this example). %) or more is determined as abnormality determination of the pressure sensors 23a to 23h. If it is above the threshold, it is determined to be abnormal, and if it is less than the threshold, it is determined to be normal. If the pressure sensor is determined to be abnormal, it is not used for pumping pressure measurement, or even if it is measured, the measurement result is adopted. do not. The error is obtained by {|P24−P23|/P24}×100, where P24 is the pressure value at the reference sensor 24 and P23 is the pressure value at each of the pressure sensors 23a to 23h.

Next, after opening the first and second valves V1 and V2 and closing the third, fifth and sixth valves V3, V5 and V6 (S14), the fifth and sixth valves V5 and V6 are closed. is opened (S15). After that, the second valve V2 is closed (S16), and the channel of the non-measuring section tube TC is communicated with the drain hole . The general controller 31 determines whether or not the elapsed time after the second valve V2 is closed has reached a predetermined time (for example, 60 minutes) or more (S17). Waiting for the passage of time until the predetermined time or longer, and in the case of an affirmative determination, output to the acquisition calculation unit 29 to specify the pressure detection value from the pressure sensors 23a to 23h as the pumping pressure and output it to the general controller 31 send instructions. The acquisition calculation unit 29 acquires the pumping pressure in response to this output instruction (S18), and outputs it to the general controller 31 together with the date and time. When the pumping pressure is input, the supervising controller 31 stores the date and time as pumping pressure data in the storage unit, and displays it on the display unit 37 in response to a display instruction or the like from the input unit 35 .

After that, the flow path control unit 28 opens the second valve V2 (S19), opens the third valve V3, and closes the fifth and sixth valves V5 and V6 (S20). As a result, the first to sixth valves V1 to V6 return to the initial state before the calibration process and pumping pressure measurement, that is, the steady state.

14a to 14h drain hole 21 pressure detection system 23a to 23h pressure sensor 24 reference sensor 27 gas delivery unit 28 flow control unit 29 acquisition calculation unit 31 general controller P21, P22, P24 connection position P23, P25 branch position TA guide pipe TAm main Line TAr Reference sensor line TAs Pressure sensor line TB Sending section branch pipe TC To-be-measured section pipe TD To-be-measured section branch pipe V1 to V9 1st to 9th valves

Claims (6)

a plurality of pressure sensors that respectively measure the pressures of the plurality of measured parts;
a reference sensor that serves as a calibration standard used to calibrate the pressure sensor;
a gas delivery unit that delivers gas to each of the reference sensor and the pressure sensor to be calibrated;
a gas feed controller that controls on and off of the gas feed to the plurality of pressure sensors and the reference sensor;
Pressurization pressure values detected by the reference sensor and the pressure sensor in a state of being pressurized to respective target pressure values by the gas, and the reference sensor and the pressure in a state of releasing pressurization by the gas A pressure detection system comprising: a calibration calculation unit that calibrates the pressure sensor based on the non-pressurized pressure value detected by the sensor. 2. The pressure detection system according to claim 1, further comprising an integrated controller for controlling said gas feed control section and said calibration calculation section. 3. The pressure detection system according to claim 1, wherein the reference sensor and each of the plurality of pressure sensors are connected in parallel to the gas delivery section through a guide tube that guides the gas. The guide tube has a main line extending from the gas delivery section, and a plurality of pressure sensor lines having one end connected to the main line and the other end connected to the pressure sensor,
a tube to be measured, one end of which is connected to the pressure sensor line and the other end of which is connected to the part to be measured;
a branch pipe for the part to be measured branched from the pipe for the part to be measured and having an open tip;
a first valve provided closer to the part to be measured than the branch position of the pipe to be measured where the branch pipe to be measured branches;
a second valve provided in the branch pipe of the part to be measured;
4. The pressure detection system according to claim 3, further comprising: a third valve provided on the main line side of the connection position of the pressure sensor line to which the tube to be measured is connected. provided in series with each other in the guide pipe between the gas delivery unit and the reference sensor and the plurality of pressure sensors, and delivering the gas from the gas delivery unit toward the reference sensor and the plurality of pressure sensors; a first delivery valve and a second delivery valve that switch on and off the
a delivery portion branch pipe branching from the guide pipe between the first delivery valve and the second delivery valve and having an open tip;
a branch valve arranged in the delivery section branch pipe;
5. The pressure sensing system of claim 3 or 4, comprising: The calibration calculation unit associates the pressurized pressure of the pressure sensor with the pressurized pressure of the reference sensor to determine the maximum detected pressure, and associates the nonpressurized pressure of the reference sensor with the nonpressurized pressure of the pressure sensor. 6. The pressure detection system according to any one of claims 1 to 5, wherein the pressure sensor is calibrated by setting a minimum detection pressure at .

Images