An automatic flow-cutting device for protecting turbine blades

Abstract

This utility model discloses an automatic flow-cutting device for protecting the turbine blades, comprising: a pipe body, with flanges symmetrically fixedly connected to the outer wall of the pipe body; a vortex flow meter fixedly connected to the inner wall of the pipe body; and a baffle fixedly connected to the inner wall of the pipe body. This utility model relates to the field of turbine flow-cutting technology. The pipe body, through a monitoring system composed of the vortex flow meter and the baffle, captures key parameters such as steam flow rate, velocity, temperature, and pressure in real time. Combined with threshold judgment by an external PLC, it can quickly trigger flow-cutting when the flow rate or velocity exceeds the limit, preventing blade failures such as cracks and fractures caused by overload, overspeed, erosion, or excessive thermal stress. Through flow diversion at the vent and absorption of fluid kinetic energy by the elastic deformation of the spring, it plays a role at the moment of valve opening and closing, effectively mitigating pressure fluctuations and impact loads, preventing the instantaneous pressure impact during flow-cutting or opening from being transmitted to the turbine inlet, and reducing disturbance to related components such as the rotor and bearings.

Description

Technical Field

[0001] This utility model relates to the field of steam turbine flow control technology, specifically a flow control device for automatically protecting the moving blades of a steam turbine. Background Technology

[0002] As the core equipment for energy conversion, the steam turbine's moving blades directly bear the impact and drive of high-temperature and high-pressure steam, making them a key component for ensuring the efficient operation of the unit.

[0003] However, in actual operation, moving blades often face multiple damage risks due to abnormal steam parameters, such as sudden increases in flow rate, excessive flow velocity, and temperature or pressure fluctuations. When the steam flow rate or flow velocity exceeds the design threshold, the blades are prone to excessive stress due to overload, which can lead to bending, cracks, or even breakage. Impurities carried by high-speed steam or airflow vibration can also exacerbate blade erosion and vibration, leading to fatigue failure. Utility Model Content

[0004] (a) Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this utility model provides an automatic flow-cutting device for protecting the moving blades of a steam turbine, which solves the problem that the moving blades often experience excessive stress due to abnormal steam parameters, leading to bending, cracking, or even breakage.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, this utility model provides the following technical solution:

[0008] An automatic flow-blocking device for protecting turbine blades includes: a pipe body, with flanges symmetrically fixedly connected to the outer wall of the pipe body; a vortex flow meter fixedly connected to the inner wall of the pipe body; a stop rod fixedly connected to the inner wall of the pipe body; a servo motor fixedly connected to the outer wall of the top of the pipe body; a rotating rod rotatably connected to the inner wall of the servo motor; a valve disc fixedly connected to the outer wall of the rotating rod; and a sealing ring fixedly connected to the outer wall of the valve disc.

[0009] Preferably, the vortex flow meter is installed outside the baffle rod, and the outer wall of the rotating rod is rotatably connected to the inner wall of the pipe body. The vortex flow meter is a commercially available Endress+Hauser ProlineProwirlF200 model. When the fluid flows through the baffle rod, vortices alternately appear on both sides of the baffle, and the rotation directions of the vortices on both sides are opposite, forming a regular vortex phenomenon. The flow meter uses a differential capacitance sensor to detect pressure changes. The vortices that detach from both sides of the baffle alternately generate positive and negative pressures. The DSC sensor responds to this pressure change, converting it into an electrical pulse signal. By measuring the vortex frequency and combining it with parameters such as temperature and pressure measured by the sensor, the volumetric flow rate and mass flow rate of the fluid can be obtained through internal calculations and transmitted to the PLC controller.

[0010] Preferably, a buffer plate and a support frame are fixedly connected to the inner wall of the tube body, a vent is provided on the outer wall of the buffer plate, a slide rod is fixedly connected to the outer wall of the support frame, a top plate is slidably connected to the outer wall of the slide rod, a rubber pad is fixedly connected to the outer wall of the top plate, and a compression spring is fixedly connected to the outer wall of the top plate on the side away from the rubber pad.

[0011] Preferably, the vents are arranged in a ring around the central point of the buffer plate, and the outer wall of the slide rod on the side away from the support frame is fixedly connected to the outer wall of the buffer plate. When the valve is opened, the fluid inertia will impact the buffer plate, and some of the fluid will be diverted through the vents in the ring array to reduce the direct impact force.

[0012] Preferably, the outer wall of the compression spring on the side away from the top plate is fixedly connected to the outer wall of the support frame, and the buffer plate is set on the side away from the vortex flow meter. The fluid pushes the top plate to move along the slide bar towards the support frame, and the compression spring is compressed. The elastic deformation of the spring absorbs the fluid kinetic energy and alleviates pressure fluctuations. The rubber pad can reduce the hard contact wear between the top plate and the buffer plate / support frame, and at the same time enhance the buffering effect, avoiding the pressure impact at the moment of throttling from being transmitted to the turbine inlet.

[0013] (III) Beneficial Effects

[0014] This invention provides an automatic flow-blocking device for protecting the moving blades of a steam turbine. It has the following beneficial effects:

[0015] (I) This vortex flow meter, through the monitoring system composed of the Endress+Hauser ProlineProwirlF200 vortex flow meter and the baffle, captures key parameters such as steam flow rate, velocity, temperature, and pressure in real time. Combined with the threshold judgment of the external PLC, it can quickly trigger the flow cut-off when the flow rate or velocity exceeds the limit. The valve disc is driven by a servo motor to achieve efficient sealing and flow cut-off. It can cut off or reduce the impact of abnormal steam on the moving blades in a short time, and fundamentally avoid the failure of blades caused by overload, overspeed, erosion or excessive thermal stress, such as cracks and fractures. It significantly extends the service life of the moving blades and reduces the unit maintenance cost.

[0016] (ii) The buffer plate, through the diversion of the vent and the absorption of fluid kinetic energy by the elastic deformation of the spring, plays a role at the moment of valve opening and closing, effectively alleviating pressure fluctuations and impact loads, preventing the instantaneous pressure impact during closure or opening from being transmitted to the turbine inlet, reducing disturbance to rotor, bearings and other related components, ensuring the stability of unit operation, and reducing the risk of chain failures caused by impact. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2 This is a partial cross-sectional structural schematic diagram of the present invention;

[0019] Figure 3 This is a schematic diagram of the support frame of this utility model;

[0020] Figure 4 This is a schematic diagram of the top plate of this utility model.

[0021] In the diagram: 1. Pipe body; 2. Flange; 3. Vortex flow meter; 4. Baffle; 5. Servo motor; 6. Rotating rod; 7. Valve disc; 8. Sealing ring; 9. Buffer plate; 91. Vent; 10. Support frame; 11. Slide rod; 12. Top plate; 121. Rubber pad; 13. Compression spring. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Please see Figure 1-4This utility model provides a technical solution: an automatic flow-blocking device for protecting turbine blades, comprising: a pipe body 1, with flanges 2 symmetrically fixedly connected to the outer wall of the pipe body 1; a vortex flow meter 3 fixedly connected to the inner wall of the pipe body 1, a stop bar 4 fixedly connected to the inner wall of the pipe body 1, a servo motor 5 fixedly connected to the outer wall of the top of the pipe body 1, a rotating rod 6 rotatably connected to the inner wall of the servo motor 5, a valve disc 7 fixedly connected to the outer wall of the rotating rod 6, and a sealing ring 8 fixedly connected to the outer wall of the valve disc 7.

[0024] The vortex flow meter 3 is installed outside the baffle 4. The outer wall of the rotating rod 6 is rotatably connected to the inner wall of the pipe body 1. The vortex flow meter 3 is a commercially available Endress+Hauser ProlineProwirlF200 model. When the fluid flows through the baffle 4, vortices alternately appear on both sides of the baffle, and the rotation directions of the vortices on both sides are opposite, forming a regular vortex phenomenon. This flow meter uses a differential capacitance sensor to detect pressure changes. The vortices that detach from both sides of the baffle alternately generate positive and negative pressures. The DSC sensor responds to this pressure change, converting it into an electrical pulse signal. By measuring the vortex frequency and combining it with the temperature, pressure, and other parameters measured by the sensor, the volumetric flow rate, mass flow rate, and other parameters of the fluid can be obtained through internal calculations and transmitted to the PLC controller.

[0025] The inner wall of the tube body 1 is fixedly connected to a buffer plate 9 and a support frame 10. The outer wall of the buffer plate 9 is provided with a vent 91. The outer wall of the support frame 10 is fixedly connected to a slide rod 11. The outer wall of the slide rod 11 is slidably connected to a top plate 12. The outer wall of the top plate 12 is fixedly connected to a rubber pad 121. The outer wall of the top plate 12 away from the rubber pad 121 is fixedly connected to a compression spring 13.

[0026] The vents 91 are arranged in a ring around the center point of the buffer plate 9. The outer wall of the slide rod 11 on the side away from the support frame 10 is fixedly connected to the outer wall of the buffer plate 9. When the valve disc 7 is opened, the fluid inertia will impact the buffer plate 9, and some of the fluid will be diverted through the vents 91 in the ring array to reduce the direct impact force.

[0027] The outer wall of the compression spring 13 on the side away from the top plate 12 is fixedly connected to the outer wall of the support frame 10. The buffer plate 9 is set on the side away from the vortex flow meter 3. The fluid pushes the top plate 12 to move along the slide rod 11 toward the support frame 10, and the compression spring 13 is compressed. The elastic deformation of the spring absorbs the fluid kinetic energy and relieves pressure fluctuations. The rubber pad 121 can reduce the hard contact wear between the top plate 12 and the buffer plate 9 / support frame 10, and at the same time enhance the buffering effect, so as to avoid the pressure impact at the moment of throttling from being transmitted to the turbine inlet.

[0028] In use, the pipe body 1 is connected to the steam turbine through the flange 2. When the steam flows through the pipe body 1, it first passes through the measurement area composed of the vortex flow meter 3 and the baffle 4. The vortex flow meter 3 transmits the data to the external PLC controller in real time. After receiving the monitoring data of the vortex flow meter 3, the external PLC controller compares it with the preset safety threshold and controls the servo motor 5 to open and close the valve disc 7.

[0029] As a vortex generator, the baffle 4 generates Karman vortex streets with opposite rotation directions on both sides of the baffle 4 when the fluid flows through it. The differential capacitance sensor of the vortex flow meter 3 detects the pressure changes generated by the vortex and converts them into electrical pulse signals. Combined with the built-in temperature and pressure detection functions, it calculates parameters such as real-time volumetric flow rate and mass flow rate and transmits the data to the external PLC controller in real time. After receiving the monitoring data from the vortex flow meter 3, the external PLC controller compares it with the preset safety threshold. When the flow rate or velocity exceeds the safety threshold, the PLC immediately sends an action command to the servo motor 5. The servo motor 5 starts and drives the rotating rod 6 to rotate, which drives the valve disc 7 to rotate synchronously until the valve disc 7 is in contact with the inner wall of the pipe body 1. The sealing ring 8 achieves the sealing and interception of the pipe body 1, cutting off or significantly reducing the steam flow to the turbine and preventing the moving blades from being continuously impacted by abnormal fluid.

[0030] When valve 7 is opened, the buffer structure inside pipe body 1 takes effect to reduce the fluid impact at the moment of opening. When valve 7 is opened, the fluid inertia will impact the buffer plate 9. Some fluid is diverted through the vent 91 of the annular array to reduce the direct impact force. The fluid pushes the top plate 12 to move along the slide rod 11 towards the support frame 10. The compression spring 13 is compressed and absorbs the fluid kinetic energy through the elastic deformation of the spring to alleviate pressure fluctuations. The rubber pad 121 can reduce the hard contact wear between the top plate 12 and the buffer plate 9 / support frame 10, while enhancing the buffering effect and preventing the pressure impact at the moment of throttling from being transmitted to the turbine inlet, further protecting the moving blades and piping system.

[0031] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An automatic flow-cutting device for protecting the motorized blades of a steam turbine, characterized in that, include: Pipe body (1), the outer wall of the pipe body (1) is symmetrically fixedly connected with flanges (2); A vortex flow meter (3) is fixedly connected to the inner wall of the pipe body (1), a stop bar (4) is fixedly connected to the inner wall of the pipe body (1), a servo motor (5) is fixedly connected to the outer wall of the top of the pipe body (1), a rotating rod (6) is rotatably connected to the inner wall of the servo motor (5), a valve disc (7) is fixedly connected to the outer wall of the rotating rod (6), and a sealing ring (8) is fixedly connected to the outer wall of the valve disc (7).

2. The flow-cutting device for automatically protecting the turbine blades according to claim 1, characterized in that: The vortex flow meter (3) is located outside the baffle (4), and the outer wall of the rotating rod (6) is rotatably connected to the inner wall of the pipe body (1).

3. The flow-cutting device for automatically protecting the turbine blades according to claim 1, characterized in that: The inner wall of the tube (1) is fixedly connected to a buffer plate (9) and a support frame (10). The outer wall of the buffer plate (9) is provided with a vent (91). The outer wall of the support frame (10) is fixedly connected to a slide rod (11). The outer wall of the slide rod (11) is slidably connected to a top plate (12). The outer wall of the top plate (12) is fixedly connected to a rubber pad (121). The outer wall of the top plate (12) away from the rubber pad (121) is fixedly connected to a compression spring (13).

4. The flow-cutting device for automatically protecting the turbine blades according to claim 3, characterized in that: The vents (91) are arranged in a ring around the center point of the buffer plate (9), and the outer wall of the slide rod (11) on the side away from the support frame (10) is fixedly connected to the outer wall of the buffer plate (9).

5. The flow-cutting device for automatically protecting the turbine blades according to claim 3, characterized in that: The outer wall of the compression spring (13) on the side away from the top plate (12) is fixedly connected to the outer wall of the support frame (10), and the buffer plate (9) is set on the side away from the vortex flow meter (3).

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