JPS63111436A - Fatigue diagnosing method for driving system for rotary machine - Google Patents

Abstract

PURPOSE:To continuously and quantitatively control the degree of fatigue of a driving system by counting driving shaft torque data and finding the degree of fatigue at a specific point, and finding the degrees of fatigue at respective parts based on previously found correlation coefficients between the rotary machine and the respective parts. CONSTITUTION:Torque signals from respective points which are transmitted from an FM telemeter 1 are received by a receiver 3. A driving shaft torque signal is converted by an A/D converter 4 from analog to digital and then supplied to a microcomputer 5. Torque data at a specific point of the driving shaft which are inputted to the computer 5 are integrated by torque ranges and stored in the memory in the computer 5. Integrated data are compared with an S-N curve set previously in the computer 5 according to a minor rule to find the degree of fatigue at the specific point. The degrees of fatigue at the respective parts are found based on the previously found correlation coefficients between the rotary machine and respective parts.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a drive system of a rotating machine having a rotating mechanism, such as a rolling mill for metal 9 paper, a shear, and other steel manufacturing machinery. This invention relates to a method for diagnosing the degree of fatigue of people.

(Prior art and its problems) Fatigue accumulates in the drive system of a rotating machine due to the repeated application of torque. Conventionally, the degree of fatigue in the drive system of rotating machinery has been measured using the X-ray method when the rotating machine is stopped.

It was measured by the ultrasonic method and the residual stress measurement method, and was measured by the AE method, fatigue calculation using a stress frequency meter, etc. during the operation of rotating machinery.

However, by stopping the rotating machine, 110 people
Since it was first possible to measure fatigue levels, it was not possible to constantly monitor fatigue levels online. On the other hand, since the measurement is performed during operation, it is extremely difficult to measure fatigue level at multiple points in a driving system, and there is a problem in that accurate fatigue level evaluation cannot be performed.

In other words, these methods cannot accurately determine the fatigue level of the drive system during steady operation of a rotating machine.

(Objective of the Invention) The object of the present invention is to solve the problems of the prior art described above, and to enable continuous, accurate and easy management of the degree of fatigue at each point of the drive system during steady operation of a rotating machine. An object of the present invention is to provide a method for diagnosing fatigue of a drive system of a rotating machine.

(T=stage to achieve the objective) In order to achieve the above objective, the fatigue diagnosis method for the drive system of a rotating machine according to the present invention measures the drive shaft torque at a predetermined point of the rotating machine, and calculates the gain obtained from the measurement. The obtained drive shaft torque data is counted, and the fatigue level at the predetermined point is determined according to the S-N curve. It is characterized by determining the degree of fatigue of each part.

(Embodiment) The drawing is a block diagram showing an example of a device configuration for realizing the method according to the present invention.

In the drawing, a torque sensor (not shown) and an induction power type FM telemeter 1 are arranged on the rolling mill drive shaft (not shown) as close to the motor as possible, and the rolling mill drive detected by the torque sensor The torque signal at a predetermined point on the shaft is wirelessly transmitted via the FM telemeter 1. The FM telemeter 1 is continuously supplied with power from an induction power supply device 2, and is configured to derive a drive shaft torque signal in a so-called free maintenance manner.

The torque signal at a predetermined point on the drive shaft transmitted from the FM telemeter 1 is received by the receiver n3. The received drive shaft torque signal is converted from an analog signal to a digital signal by an A/'D converter 4, and is then provided to a microcomputer 5.

The microcomputer 5 automatically samples and imports torque data at predetermined points on the above-mentioned driving ljJ axes online. Note that if online processing is difficult, batch processing can also be used.

The torque data at a predetermined point on the drive shaft inputted to the microcomputer 5 is accumulated for each torque range by a counting process such as the rainflow method, and is stored in the memory within the microcomviator 5 or an external storage device (not shown). be remembered. This integrated data and the S set in advance in the microcomputer 5
The degree of fatigue at a predetermined point of the drive shaft can be determined by comparing it with the -N curve based on Minor's rule (Hiragi-Masa Minor's rule can be used). Here, the S-N curve is a curve that shows the relationship between the stress that acts repeatedly and the number of repetitions until it breaks,
Minor's rule is a method of deriving the degree of fatigue from measured data according to the S-N curve.

Based on the degree of fatigue at a predetermined point determined in this way, the degree of fatigue of each part of the drive shaft is determined according to the correlation described in detail later, and these values are sequentially stored in the memory in the microcomputer 5 over time. is stored in an external storage device.

By the way, the method for calculating the correlation coefficient is as follows:
By inputting data regarding the shape of each part of the drive shaft in advance into a separate computer (not shown) and performing a simulation using modal analysis at the combination node, it is possible to determine the correlation between the degree of fatigue at a predetermined point and the degree of fatigue of each part of the drive shaft. Guide (
It is something.

Based on the above analysis results, the fatigue level of the rolling mill drive system is managed in a time-series and quantitative manner, and each part of the drive system is maintained in good condition (CB M: Condition Ba5ed M).
aintcnancc) L/Go. For example, when using online processing, the analysis results are constantly output, or the analysis results are stored in memory and read out as needed, and the rolling mill The progress of fatigue in the drive system can be diagnosed. The best analysis results are immediately after replacing the drive system mechanism, and the worst are just before the replacement, so by comparing with past diagnosis results, it is possible to determine how much fatigue has progressed. It becomes possible to make a quantitative determination. Furthermore, when starting batch processing, the analysis results for each month can be outputted as a graph, for example, and the same diagnosis as in the above-mentioned online processing can be performed.

In addition, based on the above analysis results, it is determined whether the fatigue of each part of the rolling mill drive system has reached an unacceptable level.
A warning is issued before equipment is seriously damaged. The method of determination is to compare the preset fatigue level of each part of the drive shaft with the determined fatigue level of each part, and if any one point exceeds the controlled value, it is determined to be abnormal. Conceivable.

In addition to the above-mentioned processing, it is also possible to perform constant smoothing management of rolling-like loads. In other words, by storing the measured torque data at a predetermined point on the drive shaft at all times, or by storing it in memory and outputting it only when necessary, for example in the form of a graph, you can easily determine what kind of load is being applied to the rolling mill. It is possible to know chronologically and quantitatively whether the As an example of the use of this data, a threshold value is set to measure whether the torque data at a predetermined point on the drive shaft is normal or abnormal, and if the measured torque data exceeds this threshold value, it is determined to be abnormal. For example, an alarm can be issued, and the torque waveform and elapsed time at that time may be output.

In addition, if you compare it with the above fatigue diagnosis results, if the way the load is applied changes abnormally even though the progress of fatigue is small, for example, some kind of problem will occur in the processing at the front stage of the rolling mill. It can be predicted that this may have happened.

Although this embodiment shows a case where the present invention is applied to a rolling mill, the present invention can be similarly applied to rotating machines other than rolling mills.

(Effects of the invention) As explained above, this invention is the first! According to JJ, it is possible to continuously and quantitatively control the fatigue level of the drive system of a rotating machine during steady operation. Therefore, it is possible to prevent operational troubles caused by decisive damage to the equipment.
It is possible to prevent the loss of 10 days of operation due to malfunctioning equipment. In addition, maintenance costs can be reduced because actual repairs can be carried out when the equipment is seriously damaged. In addition, drive system fatigue diagnosis can be easily and accurately performed by a single operator operating the terminal. Furthermore, since appropriate operating conditions for the rotating machine can be set based on abnormal torque data, stable operation of the equipment can be achieved, and abnormalities in product quality can be effectively prevented.

[Brief explanation of the drawing]

The drawing is a block diagram showing an example of a device configuration for implementing the method according to the present invention. 1...FM telemeter, 2...Induced lightning m device, 3
...Receiver, 4...A/D converter, 5.
・Microcomputer

Claims (1)

[Claims] (1) Measure the drive shaft torque at a predetermined point of the rotating machine, count and process the drive shaft torque data obtained by the measurement, and calculate the degree of fatigue at the predetermined point according to the S-N curve. A method for diagnosing fatigue of a drive system of a rotating machine, characterized in that the fatigue level of each part is determined from the fatigue level of the predetermined point based on a correlation coefficient with each part of the rotating machine.