Bolt stress monitoring system for water pump turbine top cover

Abstract

The present application relates to a kind of water pump water turbine top cover bolt stress monitoring system, to solve the problem that may appear inaccuracy in the process of measuring water pump water turbine top cover bolt stress in prior art.This application technical scheme is: top cover pressure measurement module, for measuring the pressure suffered by each key measuring point of top cover;Top cover bolt stress measurement module, for measuring the stress of top cover bolt;PLC controller I, electrically connected with the top cover pressure measurement module;PLC controller II, electrically connected with the PLC controller I, for calculating the theoretical stress of top cover bolt based on the top cover load calculated by PLC controller I;PLC controller III, electrically connected with the top cover bolt stress measurement module;PLC controller IV, electrically connected with the PLC controller II and PLC controller III;Alarm module, electrically connected with the PLC controller IV, for issuing alarm when alarm signal is generated by PLC controller IV.The present application is suitable for pumped storage unit technical field.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of water pump water turbine top cover bolt stress monitoring system.It is suitable for pumped storage unit technical field. BACKGROUND

[0002] Pumped storage is the most large-scale development condition of current green low-carbon clean flexible regulating power supply of electric power system, and is an important way to guarantee the safe and stable operation of electric power system.It can not only effectively promote new energy consumption, but also enhance the balancing regulation capability of electric power system.

[0003] Pumped storage power station unit is frequently started, and the operating condition is complex.The main pressure-bearing part of water pump water turbine, top cover and seat ring, are connected through high-pressure water flow, and the connection design of the two is directly related to the safety of flow passage.The connecting bolt between top cover and seat ring mainly bears the load of internal high-pressure water flow on top cover, and if the load is too large, the bolt is prone to breakage, which will cause the sealing failure between top cover and seat ring, and a large amount of water will flow into the plant, causing water flooding in the plant, and causing serious loss to the safety of the power station and personnel life.In recent years, accidents caused by top cover bolt fracture have occurred in domestic and foreign hydropower stations, which seriously threatens the safety of personnel and property in power stations.Therefore, how to accurately monitor the stress of top cover bolt is crucial to the safe operation of water pump water turbine.

[0004] At present, the stress of top cover bolt is mainly monitored by stress sheet method, strain gauge method and ultrasonic method, which mainly measures the stress of bolt by installing stress sheet, strain gauge or ultrasonic probe on the bolt, so as to reflect the stress state of bolt.Various methods described above have certain limitations in application process, for example, stress sheet method is difficult to install in some cases;stress gauge method often needs to bury stress gauge in bolt in advance, and needs to reserve installation hole in advance in the production process of bolt, which is limited in the application of existing power stations;ultrasonic method has high requirement for the calibration of measurement system.Therefore, due to the installation limitation of monitoring equipment or monitoring equipment failure, the measurement result of bolt stress may be affected by the single measurement system. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a water pump water turbine top cover bolt stress monitoring system to solve the problem of inaccurate measurement in the process of measuring the stress of water pump water turbine top cover bolt.

[0006] The technical solution adopted by the present application is: a water pump water turbine top cover bolt stress monitoring system, characterized by comprising:

[0007] A top cover pressure measurement module is used to measure the pressure of each key measuring point of top cover;

[0008] A top cover bolt stress measurement module is used to measure the stress of the top cover bolt.

[0009] A PLC controller I is electrically connected with the top cover pressure measurement module, and is used to calculate the load of the top cover based on the pressure of each key measurement point of the top cover measured by the top cover pressure measurement module.

[0010] A PLC controller II is electrically connected with the PLC controller I, and is used to calculate the theoretical stress of the top cover bolt based on the load of the top cover calculated by the PLC controller I.

[0011] A PLC controller III is electrically connected with the top cover bolt stress measurement module, and is used to obtain the actual stress of the top cover bolt measured by the top cover bolt stress measurement module.

[0012] A PLC controller IV is electrically connected with the PLC controller II and the PLC controller III, and is used to compare the theoretical stress of the top cover bolt of the PLC controller II and the actual stress of the top cover bolt of the PLC controller III, and generate an alarm signal when the deviation between the two exceeds a preset range.

[0013] An alarm module is electrically connected with the PLC controller IV, and is used to issue an alarm when the PLC controller IV generates an alarm signal.

[0014] The key measurement points on the top cover include a pressure measurement point A between the movable guide vane and the fixed guide vane, a pressure measurement point B between the runner and the movable guide vane, a top cover inlet pressure measurement point C, a labyrinth ring inlet pressure measurement point D, and a labyrinth ring outlet pressure measurement point E.

[0015] The top cover pressure measurement module includes a measuring head and a pressure sensor corresponding to each key measurement point, wherein the measuring head is installed at the corresponding measurement point position, and a pipeline for guiding the pressurized water to the pressure sensor is arranged between the measuring head and the corresponding pressure sensor.

[0016] The top cover bolt stress measurement module has an ultrasonic probe arranged on the top cover bolt, and an ultrasonic emission and signal acquisition device electrically connected with the ultrasonic probe.

[0017] The ultrasonic probe is installed on the upper end of the top cover bolt.

[0018] The beneficial effects of this invention are as follows: This invention measures the pressure at each key measuring point of the top cover using a top cover pressure measurement module, and calculates the top cover load based on the pressure at each key measuring point, thereby obtaining the theoretical stress of the top cover bolts; at the same time, it uses a top cover bolt stress measurement module to measure the actual stress of the top cover bolts and compares it with the theoretical stress of the top cover bolts, which serves the purpose of mutual verification, avoiding the inaccurate measurement problems caused by equipment failure and other reasons in previous single bolt stress measurement systems, thus ensuring the reliability of the bolt stress monitoring system. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the system architecture for an example.

[0020] Figure 2 This is a schematic diagram of the arrangement of measuring points and probes in the embodiment.

[0021] 1. Probe; 2. Pipeline; 3. Pressure sensor; 4. Cable; 5. PLC controller I; 6. PLC controller II; 7. Ultrasonic probe; 8. Ultrasonic emission and signal acquisition device; 9. PLC controller III; 10. PLC controller IV. Detailed Implementation

[0022] like Figure 1 As shown, this embodiment is a water pump turbine top cover bolt stress monitoring system, including a top cover pressure measurement module, a top cover bolt stress measurement module, PLC controller I, PLC controller II, PLC controller III, PLC controller IV and an alarm module.

[0023] In this example, the top cover pressure measurement module is used to measure the pressure at various key points on the top cover (including pressure measurement point A between the movable and fixed guide vanes, pressure measurement point B between the impeller and the movable guide vanes, pressure measurement point C at the top cover inlet, pressure measurement point D at the labyrinth ring inlet, and pressure measurement point E at the labyrinth ring outlet). Figure 2 The pressure is controlled by a probe and a pressure sensor that are set up one by one for each key measuring point. The probe is set at the corresponding key measuring point and extends to the corresponding pressure sensor through the pipeline. The probe leads pressurized water to the pressure sensor through the pipeline and the pressure sensor measures the pressure at the corresponding measuring point.

[0024] In this embodiment, the stress measurement module for the top cover bolts has an ultrasonic probe located at the upper end of the top cover bolts (see...). Figure 2 The ultrasonic transmitter and signal acquisition device is electrically connected to the ultrasonic probe via a cable. The ultrasonic transmitter and signal acquisition device can transmit ultrasonic signals to the ultrasonic probe for bolt stress measurement. At the same time, the ultrasonic probe transmits the top cover bolt stress measurement signal to the ultrasonic transmitter and signal acquisition device through the transmission cable 4.

[0025] The PLC controller I is electrically connected with the pressure sensor in the top cover pressure measuring module through a cable in this embodiment, and is used to acquire the pressure borne by each key measuring point of the top cover measured by the top cover pressure measuring module, and calculate the load of the top cover by combining with a preset corresponding empirical formula.

[0026] The PLC controller II is electrically connected with the PLC controller I through a cable in this embodiment, and is used to acquire the load of the top cover calculated by the PLC controller I, and calculate the theoretical calculation stress of the top cover bolt by combining with a preset corresponding empirical formula.

[0027] The PLC controller III is electrically connected with the ultrasonic emission and signal acquisition device in the top cover bolt stress measuring module through a cable in this embodiment, and is used to acquire the actual stress of the top cover bolt measured by the top cover bolt stress measuring module.

[0028] The PLC controller IV is electrically connected with the PLC controller II and the PLC controller III through a cable in this embodiment, and is used to compare the theoretical stress of the top cover bolt of the PLC controller II and the actual stress of the top cover bolt of the PLC controller III, and generate an alarm signal when the deviation between the two exceeds a preset range.

[0029] The alarm module is electrically connected with the PLC controller IV through a cable in this embodiment, and is used to send an alarm when the PLC controller IV generates an alarm signal.

[0030] The above PLC controllers are described separately in this embodiment, and it does not mean that multiple PLC controllers must be used to realize this embodiment. The above multiple PLC controllers are described separately mainly to facilitate the distinction, and a PLC controller can be used to realize the functions of the above multiple PLC controllers to save costs.

[0031] Those skilled in the art can understand that the above description is only preferred examples of the present application, and is not used to limit the present application. Although the application is described in detail with reference to the foregoing examples, those skilled in the art can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacements for part of the technical features. Any modification, equivalent replacement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A stress monitoring system for top cover bolts of a water pump turbine, characterized in that, include: The top cover pressure measurement module is used to measure the pressure at various key measuring points on the top cover. Top cover bolt stress measurement module, used to measure the stress of top cover bolts; PLC controller Ⅰ is electrically connected to the top cover pressure measurement module and is used to calculate the load of the top cover based on the pressure measured by the top cover pressure measurement module at each key measuring point of the top cover. PLC controller II is electrically connected to PLC controller I and is used to calculate the theoretical stress of the top cover bolts based on the top cover load calculated by PLC controller I. PLC controller Ⅲ is electrically connected to the top cover bolt stress measurement module and is used to obtain the actual stress of the top cover bolt measured by the top cover bolt stress measurement module; PLC controller Ⅳ is electrically connected to PLC controller Ⅱ and PLC controller Ⅲ, and is used to compare the theoretical stress of the top cover bolt of PLC controller Ⅱ with the actual stress of the top cover bolt of PLC controller Ⅲ, and generate an alarm signal when the deviation between the two exceeds a preset range; An alarm module, electrically connected to the PLC controller IV, is used to issue an alarm when the PLC controller IV generates an alarm signal.

2. The water pump turbine top cover bolt stress monitoring system according to claim 1, characterized in that: The key measuring points on the top cover include pressure measuring point A between the movable guide vane and the fixed guide vane, pressure measuring point B between the impeller and the movable guide vane, pressure measuring point C at the top cover inlet, pressure measuring point D at the labyrinth ring inlet, and pressure measuring point E at the labyrinth ring outlet.

3. The water pump turbine top cover bolt stress monitoring system according to claim 1 or 2, characterized in that: The top cover pressure measurement module includes a probe and a pressure sensor corresponding to each key measuring point. The probe is installed at the corresponding measuring point, and a pipeline is provided between the probe and the corresponding pressure sensor to lead pressurized water to the pressure sensor.

4. The water pump turbine top cover bolt stress monitoring system according to claim 1, characterized in that: The top cover bolt stress measurement module has an ultrasonic probe mounted on the top cover bolt, and an ultrasonic transmitting and signal acquisition device electrically connected to the ultrasonic probe.

5. The water pump turbine top cover bolt stress monitoring system according to claim 4, characterized in that: The ultrasonic probe is mounted on the upper end of the top cover bolt.

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