JPH02212722A - Handy diagnostic apparatus for construction - Google Patents

Abstract

PURPOSE:To detect the presence of abnormality by a method wherein an accelerometer is mounted at a required point as sensor and necessary numerals of frequency, damping rate and the like at parts of a construction are calculated from the resulting output signals to be compared with reference values. CONSTITUTION:Sensors 2 are mounted at required points of a construction 1, output signals thereof are introduced to a signal pickup section 4, where they are converted into vibration signals without noise to be sent to an arithmetic section 5, which 5 performs a calculation of a natural frequency at positions of setting the sensors by the signals inputted and calculations for correlation with other signals, a damping rate of the signals and the like and sends the results of the calculations to a judging section 6. The judging section 6 having a recording/memory section 7 judges whether the construction 1 is abnormal by performing a storage of various signals, a comparison thereof with reference values according to changes in the signals with the passage of time. The results of the judgement are shown on a display section 8 and at the same time, an alarm is generated.

Description

[Detailed Description of the Invention] [Purpose of the Invention (Industrial Application Field) The present invention provides a simple structure that can detect the presence or absence of an abnormality in a structure without disassembling or stopping operation. Related to diagnostic equipment.

(Prior art) For example, in order to investigate the occurrence of cracks in a structure such as a nuclear reactor pressure vessel, the loosening of mounting parts or bolts, etc., it is necessary to stop the operation of the structure or, in the case of complex structures, It is necessary to disassemble it. In this state, the presence or absence of an abnormality is detected by visual observation, ultrasonic flaw detection, color check, X-ray photography, etc.

(Problem to be solved by the invention) As mentioned above, stopping the operation of a structure poses a problem in terms of the operating rate of the device, and disassembling and reassembling it for diagnosis requires a long time. Necessary and undesirable.

The present invention has been made based on the above-mentioned circumstances, and is capable of detecting the occurrence of an abnormality that may hinder the operation and operation of the device in the early stage, without stopping the operation of the device, disassembling the device, etc. The purpose is to provide a simple structure diagnosis device that notifies the necessity of inspection.

[Structure of the Invention] (Means for Solving the Problems) The simple structure diagnosis device of the present invention comprises a plurality of sensors (acceleration rate) attached to required parts of a structure and output signals of five of these sensors. A signal acquisition section that generates vibration signals, and calculation of the natural frequency at the sensor installation position based on the vibration signal from this signal acquisition section, correlation with other sensor signals, calculation of the attenuation rate of each sensor's signal, etc. and a recording/storage unit for receiving the calculation results of the calculation unit, storing the various input signals, and changing the signals over time.
The present invention is characterized in that it has a determining section that compares these with standard values and determines whether or not there is an abnormality in the structure, and a display section that displays the determination result of the determining section.

(Function) In the simple structure diagnosis device of the present invention having the above configuration, calculation of the natural frequency at the sensor installation position based on the signal inputted in the calculation section, correlation with other signals, attenuation rate of each signal, etc. It performs calculations and sends the calculation results to the judgment unit.

The judgment section has a recording/storage section, and stores the various input signals, changes in those signals over time, compares them with standard values, etc., and determines the structure. Determine whether there is any abnormality.

The judgment result of the judgment section is displayed on the display section, and an alarm is generated at the same time.

Therefore, by appropriately setting at which value the deviation from the standard value is determined to be abnormal, accidents can be easily prevented.

(Embodiment) Fig. 1 is a block diagram of one embodiment of the present invention, and Fig. 2 is a block diagram of an embodiment of the present invention.
The figure shows the concept of its basic configuration. In FIG. 1, sensors 2 (representative in the figure, only the locations are shown) are attached to required locations of a structure 1, and the output signals of the sensors 2 are transmitted via a cable 3 to a signal receiving section 4.
Here, it is made into a noise-free vibration signal and sent to the calculation section 5.

The above sensor 2 is generally an accelerometer, and it is desirable to use an accelerometer with sufficient reliability depending on the installation environment, such as in the air, underwater, low temperature, high temperature, etc.

The calculation unit 5 calculates the natural frequency at the sensor installation position based on the input signal, the correlation with other signals, the attenuation rate of each signal, etc., and sends the calculation results to the judgment unit 6.

This judgment unit 6 has a recording/storage unit 7, which stores the various input signals, changes in these signals over time,
By comparing them with their standard values, etc., the structure 1
Determine whether there is any abnormality.

The judgment result of the judgment section is displayed on the display section 8, and an alarm is issued at the same time.

In particular, in the device of the present invention, the dominant frequency (natural frequency)
It is also possible to constantly monitor factors such as temporal changes in , and sudden increases in response values at dominant frequencies.

Furthermore, in the apparatus of the present invention, in addition to recording and monitoring the vibration take during normal operation, it is also possible to confirm and check the natural frequency by periodically performing a hammering test.

[Effects of the Invention] The device of the present invention having the above configuration can not only measure the vibration of a structure or the rotational frequency of a general rotating machine, but also use accelerometers as sensors at required locations on the structure or rotating machine. is installed, and the necessary values such as the vibration frequency of each part of the structure and its damping rate are calculated from the output signals, and by comparing these with standard values, it is possible to detect the presence or absence of an abnormality and issue an alarm. It is something that emits. Therefore, if you appropriately set the value at which the deviation from the standard value should cause an alarm to be issued,
It is possible to prevent problems with structures.

Furthermore, if full-scale inspections and inspections are performed in response to the occurrence of the above-mentioned alarm, inspections and inspections can be carried out at a better timing than mechanical periodic inspections and inspections, ensuring the reliability of structures and Inspection and inspection costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of one embodiment of the present invention. FIG. 2 is a diagram showing the concept of its basic configuration. 1... Structure 2... ・Sensor ３・・・・・・Cable 4...Signal acquisition section 5... Arithmetic section 6... ・Judgment Department 7...Record/storage section 8... ・Display section

Claims (1)

[Claims] Multiple sensors (accelerometers) attached to required parts of the structure, a signal acquisition section that uses the output signals of these sensors as vibration signals, and a sensor installation that receives the vibration signal from this signal acquisition section. The controller is equipped with a calculation unit that calculates the natural frequency at a position, correlation with other sensor signals, attenuation rate of each sensor signal, etc., and a recording/storage unit that receives the calculation results of the calculation unit, and a determination unit that determines whether or not there is an abnormality in the structure by storing various signals, changes in these signals over time, and comparing them with standard values;
A simple structure diagnosis device comprising: a display section that displays the judgment result of the judgment section.