Before the critical speed before the critical speed of the friction vibration, that is, w 1The mechanism of the vibration of the bending axis of the frictional frame The bending vibration of the bending axis of the bookmark1 refers to the case where the surface of the large shaft is sharply increased after the rotor is rotated at a high speed, and the surface of the large shaft is rubbed against a stationary component such as a steam seal or a shaft seal. A significant temperature difference is generated with the surrounding metal, and the rotor will undergo thermal bending. When the thermal stress caused by the expansion of the metal exceeds the yield limit of the material, the rotor is plastically deformed, causing permanent bending. 1.1 Friction and vibration mechanism of single-disc rotor system The characteristic equation of the single-disk rotor damping system is: the solution of the available equation: below the critical speed, the dynamic disturbance of the middle part of the rotor increases with the square of the rotational speed, the difference is not The balance part is judged by the phase angle difference between the rubbing high position and the rotor mass eccentricity at the working speed of the unit a<90 degrees, the eccentricity will cause friction, and the frictional heat bending will further increase the eccentric vicious cycle; at the first critical speed Above, the dynamic disturbance degree in the middle of the rotor decreases with the rotation speed, and the phase angle difference between the friction high position and the rotor mass eccentricity is >90 degrees, forming a benign cycle in which the friction bending axis reduces eccentricity and the small eccentricity causes small friction. The vibration of the frictional bending axis occurring at both ends of the rotor is the same as that of the first critical speed. However, the frictional bending axis above the first critical speed needs to be divided into two sections for analysis. One section is the first-order vibration mode and the second-order vibration is not regressed. The type has not yet started the main mode, and its mechanism is the same as that of the single-disc rotor. The other is that the first-order mode basically eliminates the second-order mode and plays a leading role. The mechanism of the frictional bending vibration seems to be contrary to the traditional friction. The bending axis vibration mechanism, because the dynamic disturbance at both ends of the rotor increases with the increase of the rotational speed at this stage, the phase angle difference between the friction high position and the rotor mass eccentricity is a < 90 degrees, which is not the case, because the friction point occurs at the two ends of the rotor. As long as the critical speed is understood as the second critical speed, everything conforms to the mechanism of the friction bending vibration. 1.3 Discrimination of the friction part of the on-axis shaft The discrimination of the frictional bending part is similar to the fundamental frequency vibration of the unbalanced weight part of the rotor, and the discriminating of the frictional bending part is the amount of vibration change when the unit is running at a certain speed. That is, when the vibrational co-directional component of the rotor increases significantly and the reverse component does not increase much, the frictional bending axis should be in the middle of the rotor; conversely, when the vibrational back component of the rotor increases significantly and the same component increases little, The friction bending axis should be at both ends of the rotor; when the two are changing at the same time, the friction bending axis may be one end of the rotor. 2 Treatment of several friction and vibration problems of the Capricorn shaft 2.1 Analysis and treatment of the high and medium pressure rotor friction bending axis of Wenzhou 300MWA unit On July 6, 2001, the unit was started for the first time, and the speed was increased to 2040/min according to the normal starting sequence. The vibration of the unit is normal. The vibration of No. 1 and No. 2 watts is 49. 9Z44 and 29.3Z106, but then the vibration of No. 1 and No. 2 watts begins to climb. After 90 minutes, the vibration of No. 1 and No. 2 watts reaches 108Z64 and 60.985 (see details) 2.2 Beilun 600MW1 several groups of low-pressure rotor friction bending axis vibration analysis and processing operation, 9:10, a large vibration alarm occurred, the vertical direction of the 8th watt axis vibration 127xim based on the fundamental frequency component. Looking at the historical curve of vibration changes, it can be seen that before 8:15, the shaft vibrations of No.7 and No.8 have been stable at 1938 and 15Z176. After 8:15, the vibration of the unit began to climb to 9:10, No. 7, The 8th axis vibration is 90Z152 and 125Z83. The vibration co-directional and reverse components change 166Z293 and 155Z36 respectively, which is in accordance with the vibration mechanism of the frictional bending axis at both ends of the rotor. However, if the rotor is uniformly rubbed at both ends, its co-directional component should not be so large. The increase, if estimated by balance, should be at the single end of the 8th watt. The 500/min stable operation aims to reduce the second-order dynamic disturbance of the rotor by reducing the speed, so that the friction point friction strength is reduced. Why choose to stabilize at 2500r/min because on the basis of trying to avoid the rotor and the blade criticality, it is desirable to stabilize the speed at a higher than the first critical point and not in the benign cycle speed region dominated by the second mode; for example, direct shutdown , slow down the first H switch Dong data display. The data shows that the DEH system displays to the operator the output values ​​of the operating parameters, the setpoints and the internal state of the regulation system. Special parameters are displayed. The special parameter display is some common important parameters that the operator applies to the system for display. Graphic display. The DEH graphical display has a total of sixteen drawings, including operating parameter curves, hardware faults, critical sensor faults, digital trend displays, analog trend displays, valve position commands and feedback displays, and alarm flicker. print. Printed content includes automatic printing of running reports, screen printing, and over-limit alarms and accident recalls. The operator counts the 10 1 printer h computer +1 operation keyboard liquid device h electronic controller DEH control diagram can be seen that almost all information of the steam turbine monitoring system is transmitted to people through the vision, ignoring the human senses Characteristics. In the signal system of the centralized control room, except for the accidental horn, all are visual signals. There are hundreds of surveillance projects, all of which are visually input into the brain, which can cause long-term overload and fatigue of the eyes, reduce visual recognition and response ability, and reduce human reliability and rapidity. 2. The responsiveness of humans decreases with the increase of the amount of information. The responsiveness of the operating personnel to the turbine monitoring system under the accident is weakened with the increase of the amount of information. The speed at which operators receive information is limited, and the human-machine system can work reliably and efficiently only when the speed displayed by the turbine monitoring system is basically matched with the speed at which people receive information. The amount of information passed through the assembly has caused people to quickly fatigue. The first phase of the control room is too large compared to the second phase. There are too many meters. Many worthless meters in a certain period hinder the operators from capturing useful information in time, which increases the burden of vision and brain. , speeding up their fatigue. In the event of an accident, a large number of parameters drastically changed the sound and light alarms, and the control room was constantly on the phone. The normal psychological and physiological state of the operators suddenly became extremely tense. He has to quickly accept a variety of changing parameters and sound and light signals from the monitoring dial and the microcomputer, immediately process it in the brain, make various judgments, and then operate the corresponding mechanism. When there is only one alarm signal, the operating personnel can generally handle it correctly. When multiple signals appear at the same time and are related to each other, the operating personnel often have no choice but to increase the number of misoperations. 3 For the improvement of existing ergonomic problems, there are two ways to improve: some of the alarm content is recorded on the tape in advance, and the program controls the selection. For signals with small probability events, repeated input in different sensory channels can improve the reliability of people receiving signals. In order to increase the amount of information the operator accepts, the identification mark of the information should be technically added. For example, it can be displayed in different colors according to the importance of the signal, and in different colors. 2 This point, there are three ways to improve: For power plants with strong technical strength, you can write an accident information processing program, intelligently display alarm information and guide operators to operate. Imagine that the alarm system provides intelligent information according to the logical sequence of the operating personnel's thoughts. For example, if the shaft seal is supplied with steam to cause the vacuum to reduce the vacuum protection, the machine should be stopped according to the accident, then the operator will have the direction when receiving the first alarm. Observe the shaft seal steam supply pressure and vacuum gauge, not be confused by other signals. When the second alarm is received, the load, oil stroke, etc. will be observed, and the shutdown will be stopped in an orderly manner after the shutdown. Regularly learn the operating procedures, adapt the operators to the large-scale simulation control room, and organize anti-accident drills. In the microcomputer, all the information is grouped according to the working conditions of the unit, and it is reasonably called on the CRT according to the working conditions, which will greatly reduce the burden on the operating personnel. For example, when the load is increased, only the main steam pressure, temperature, load, cylinder wall temperature difference, differential expansion and other parameters are displayed. Other parameters are not abnormally output, and the input information is sampled point by point, and the output is classified. The information model reflects the actual situation of the controlled object and the amount of information is appropriate, prompting the operating personnel to perform normal functions. 4 Conclusion This paper discusses two ergonomic problems in the microcomputer monitoring system of thermal power plant steam turbines, namely: first, the microcomputer monitoring system ignores the characteristics of human multi-sensory; second, the response of the operating personnel to the turbine monitoring system under the accident The ability decreases as the amount of information increases. Then from the perspective of the power plant, the authors believe that the design of the turbine computer monitoring system is more critical in the scientific and more advanced design of ergonomics. (Continued from page 170) Criticality, excessive turbulence may increase damage to the shaft and bearings. After taking this measure, the two-watt vibration gradually decreased to normal, and then rose to 3,000/min and the vibration was normal after the load was applied to the mesh. 3 Conclusions (1) According to the climb and phase changes of the vibration, the vibration of the frictional bending axis is determined. According to the change of the vibration at both ends of the rotating shaft, the friction part is an effective method for dealing with the bending vibration of the shaft; the starting process of the unit passes the first critical speed region. It is inevitable that the collision between the static and the static is required. The vibration processing should make full use of the dynamic disturbance characteristics of the rotor. The friction at the working speed should be determined by the friction. It is an effective measure to reduce the speed to the speed range. Blindly shut down, causing further damage to the rotor and bearings. (3) Treatment of vibrations Light friction vibration The general treatment method is to change the rotational speed. By changing the rotational speed, the friction point is changed to avoid frictional accumulation of heat and causing the bending axis. Since the previous analysis and diagnosis have shown that the friction of this unit occurs in the middle of the rotor, the 2040r/min warming speed has been above the first critical speed of the high and medium pressure rotor. If the speed reduction process is used, the random group speed drops, high school. The dynamic disturbance in the middle of the compression rotor will become larger as the rotational speed approaches the first critical rotational speed of the high and medium pressure rotor, and the result will inevitably aggravate the friction and cause a permanent bending of the large shaft. Using the speed-up treatment, the random group rotation speed rises, and the dynamic disturbance degree of the middle part of the high- and medium-pressure rotor will become smaller as the rotation speed is far away from the first critical speed of the rotor, thereby reducing friction, so it is decided to shorten the unit warm-up time and increase in advance. From the speed curve of No.1 and No.2 axis, it can be known that the same direction components of No.1 and No.2 axis increase from the original 68.7Z66 to 166Z72, the change reaches 104277, and the phase of the in-phase vibration increases, which is higher than the first critical speed. The mechanism of frictional vibration; the reversal component of No.2 and No.2 axis vibrations increased from 445Z9 to 55.640, and the change was only 29Z273. It can be concluded that the reason for the large vibration of No.1 and No.2 axis is frictional bending axis vibration and friction point. In the middle of the shaft. 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