Novel water turbine guide vane shear pin annunciator

Abstract

The utility model provides a novel water turbine guide vane shear pin annunciator which comprises a shear pin and a signal system, the shear pin is a cylindrical pin which is arranged on a guide vane arm and is easy to shear, the signal system comprises a plurality of pressure sensors and a baffle, the pressure sensors are arranged on corresponding main crank arms, the baffle is arranged on a movable guide vane, and the pressure sensors are arranged on the movable guide vane. And the signal system is connected with the monitoring system. The device is clear in structure and simple in principle, can predict the possible shearing behavior of the shear pin in advance by dynamically monitoring the real state of the shear pin, and achieves the purposes of reducing the shearing frequency of the shear pin, reducing the checking and replacing work of the shear pin, simplifying the maintenance construction difficulty and improving the normal operation utilization rate of a unit. And finally, the quality and efficiency are improved from the technical means.

Description

Technical Field

[0001] The utility model relates to the technical field of a water turbine guide vane shear pin signal device, in particular to a novel water turbine guide vane shear pin signal device. Background Art

[0002] The shear pin of the turbine is sheared off during operation to prevent the guide vane from being damaged due to being stuck by foreign objects or other reasons. By shearing off the shear pin, the faulty guide vane is out of control, and other guide vanes can still be closed normally, thus effectively protecting the safe operation of the turbine unit. At present, the shear pin signal of the guide vane shear pin of large-scale mixed flow turbine units mostly adopts two methods:

[0003] 1. Short-stroke switch. Monitor the relative position between the movable guide vane end cap and the main crank arm. The contact of the stroke switch installed on the movable guide vane crank arm is in the prefabricated groove of the movable guide vane end cap. If the two have a certain degree of relative displacement, the contact will leave the groove and compress the stroke action. At this time, it is judged that the shear pin is cut off, the movable guide vane is out of control, and a signal alarm is issued at the same time.

[0004] 2. Insertion sensor. Monitor the relative position between the movable guide vane and the main crank arm. If there is a certain degree of relative displacement between the two, the insertion sensor will be crushed due to compression. At this time, the signal circuit is connected, and it is judged that the shear pin is cut off, the movable guide vane is out of control, and a signal alarm is issued at the same time.

[0005] Since the turbine unit has a large number of movable guide vanes and the shear pin signal is an important condition for determining emergency shutdown, the monitoring requirements for this signal are relatively high.

[0006] The current shear pin signal monitoring method has three shortcomings:

[0007] 1. For the inserted shear pin annunciator, once the shear pin is sheared, the slot needs to be cleaned. The slot is very narrow and difficult to clean. And the position between the end cap and the main crank arm of the movable guide vane must be completely consistent with that before the maintenance after the maintenance, otherwise the annunciator cannot be inserted into the slot, resulting in the annunciator being unable to truly feedback the shear pin status and becoming invalid. This has indirectly improved the maintenance process level of the turbine unit and increased the difficulty of maintenance construction.

[0008] 2. For the short-stroke switch-type shear pin signaler, the position between the end cap and the main crank arm of the movable guide vane after maintenance must be completely consistent with that before maintenance, otherwise the signaler contact cannot be normally pressed into the prefabricated groove of the end cap, which may cause the signaler to fail to truly feedback the shear pin status. This has indirectly improved the maintenance process level of the turbine unit and increased the difficulty of maintenance construction.

[0009] 3. After the shear pin is actually sheared off, the inspection and replacement work is very cumbersome, and it will waste a lot of time for the normal operation of the unit. The current shear pin signal monitoring method can only provide signal feedback after the shear pin is sheared off, and it is impossible to predict in advance, and it is also impossible to avoid the shear pin from actually shearing off by adjusting the opening of the movable guide vane. Therefore, it is time-consuming and labor-intensive, the monitoring level is limited, and there is a large room for improvement.

[0010] Therefore, a novel water turbine guide vane shear pin signal device is urgently needed to solve the above problems. Summary of the invention

[0011] The purpose of the utility model is to overcome the above-mentioned shortcomings and provide a novel turbine guide vane shear pin signal device to solve the problems raised in the background technology.

[0012] In order to solve the above technical problems, the utility model adopts the following technical solutions: a novel turbine guide vane shear pin signal device, comprising a shear pin and a signal system, wherein the shear pin is a cylindrical pin arranged on the guide vane arm and is easy to shear off, the signal system comprises a plurality of pressure sensors and baffles, the pressure sensors are arranged on the corresponding main crank arms, the baffles are arranged on the movable guide vanes, and the signal system is connected to a monitoring system.

[0013] Preferably, the pressure sensor is provided with a wireless transmission module, and the pressure sensor corresponds to the baffle plate one by one.

[0014] Preferably, the output end of the wireless transmission module is wirelessly connected to the receiving end of the monitoring system.

[0015] The utility model has the following beneficial effects:

[0016] 1. The device is flexible to disassemble, easy to maintain and replace, and simplifies the difficulty of maintenance and construction;

[0017] 2. The utility model can reduce the frequency of shearing pin shearing and reduce the inspection and replacement work of shearing pin;

[0018] 3. The utility model can improve the utilization rate of the normal operation of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic cross-sectional diagram of the overall structure of the utility model;

[0020] Figure 2 It is a schematic top view of the overall structure of the utility model;

[0021] Figure 3 This is a schematic diagram of the operation logic structure of the utility model. DETAILED DESCRIPTION

[0022] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0023] See also Figures 1 to 3 A new type of turbine guide vane shear pin signaler includes a shear pin 1 and a signal system 2. The shear pin 1 is a cylindrical pin that is arranged on the guide vane arm and is easy to shear. The signal system 2 includes a plurality of pressure sensors 2.1 and baffles 2.2. The pressure sensor 2.1 is arranged on the corresponding main crank arm 3, and the baffle 2.2 is arranged on the movable guide vane 4. The signal system 2 is connected to the monitoring system. The main purpose of the utility model is to dynamically monitor the real state of the shear pin, predict the possible shearing behavior of the shear pin in advance, and control the guide vane opening by linkage with the speed governor, so as to avoid the actual shearing of the shear pin, so as to reduce the shearing frequency of the shear pin, reduce the inspection and replacement work of the shear pin, simplify the difficulty of maintenance and construction, and improve the utilization rate of the normal operation of the unit, and finally improve the quality and efficiency from the technical means.

[0024] Preferably, the pressure sensor 2.1 is provided with a wireless transmission module, and the pressure sensor 2.1 corresponds to the baffle 2.2 one by one. A pressure sensor 2.1 is arranged on each main crank arm 3, and a baffle 2.2 is installed on each movable guide vane 4. The pressure sensor 2.1 contacts the baffle 2.2 to monitor the relative force between the movable guide vane 4 and the main crank arm 3 in real time.

[0025] Preferably, the output end of the wireless transmission module is connected to the receiving end of the monitoring system via wireless. This design reduces line connections and is more convenient for mechanical operation and maintenance.

[0026] The working principle of this embodiment is as follows:

[0027] Under normal circumstances, the main crank arm 3 drives the movable guide vane 4 to rotate, thereby increasing or decreasing the opening of the movable guide vane 4. When a foreign object is stuck between adjacent movable guide vanes 4, the main crank arm 3 cannot control the rotation of the movable guide vane 4 to increase or decrease the opening of the guide vane. At this time, the relative force between the main crank arm 3 and the movable guide vane 4 surges, and the pressure value monitored by the two adjacent pressure sensors 2.1 exceeds the threshold. At the same time, an alarm signal is sent to the monitoring system, and the monitoring system controls the movable guide vane 4 to continue to step in the reverse direction by 1% until the pressure value of the pressure sensor 2.1 is less than the threshold. If the movable guide vane 4 steps in the reverse direction to 100% opening or the pressure value of the same measuring point exceeds the threshold again during the movement of the movable guide vane 4 within 3 minutes, the monitoring system 5 controls the water inlet gate to fall, issues an alarm, and reminds the operation and maintenance personnel to conduct drainage inspections.

[0028] The above embodiments are only preferred technical solutions of the present invention and should not be regarded as limitations of the present invention. The protection scope of the present invention shall be the technical solutions recorded in the claims, including equivalent replacement solutions of the technical features in the technical solutions recorded in the claims. That is, equivalent replacement improvements within this scope are also within the protection scope of the present invention.

Claims

1. A novel turbine guide vane shear pin signal device, comprising a shear pin (1) and a signal system (2), characterized in that: The shear pin (1) is a cylindrical pin arranged on the guide vane arm and is easy to shear off. The signal system (2) comprises a plurality of pressure sensors (2.1) and baffles (2.2). The pressure sensors (2.1) are arranged on the corresponding main crank arms (3). The baffles (2.2) are arranged on the movable guide vanes (4). The signal system (2) is connected to a monitoring system.

2. According to claim 1, a novel turbine guide vane shear pin signal device is characterized in that: The pressure sensor (2.1) is provided with a wireless transmission module, and the pressure sensor (2.1) corresponds to the baffle (2.2) in a one-to-one manner.

3. According to claim 2, a novel turbine guide vane shear pin signal device is characterized in that: The output end of the wireless transmission module is connected to the receiving end of the monitoring system via wireless.

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