A simulation device and simulation method for the rubbing test of a steam turbine shroud

Abstract

The present invention belongs to the technical field of simulation test technology for turbine shroud rubbing in nuclear power plants, and specifically relates to a simulation device for turbine shroud rubbing test and a simulation method thereof, including: an installation platform, a shroud fixing device, a loading device, a vibration signal input system, and an experimental data acquisition system; the installation platform includes: a base, a crank handle clamp, and a T-shaped load-bearing plate; the crank handle clamp is arranged on the top of the base, one end of the shroud fixing device is clamped and fixedly connected with the crank handle clamp, and a loading device is fixed on the other end of the shroud fixing device; the vibration signal input system is arranged on one side of the base through the T-shaped load-bearing plate; a plurality of waist-shaped through holes are evenly distributed on the side of the base where the T-shaped load-bearing plate is arranged.

Description

Technical Field

[0001] The present invention belongs to the technical field of simulation tests for the rubbing of turbine shroud bands in nuclear power plants, and particularly relates to a simulation device for the rubbing test of turbine shroud bands and a simulation method thereof. Background Art

[0002] The blade is one of the core components of a steam turbine, and its safety is very important for the normal operation of the steam turbine. Blade failure caused by vibration is one of the main accident forms of blades. In order to reduce the vibration of blades, the method of adding a damping structure to the blades is generally adopted for steam turbine blades. Theory and engineering practice show that the damping structure has a good vibration reduction effect.

[0003] As a kind of damping structure, the shroud band has been widely used in steam turbines. However, at present, the research on the damping mechanism and damping effect of the shroud band is still in the exploratory stage, and there are still great deficiencies, which cannot provide more theoretical basis for the engineering design of the shroud band structure. One reason is that the indirect contact rubbing motion of the shroud band is very complex, involving the field of nonlinear mechanics, and the theoretical research is difficult; the other reason is that there are difficulties in data acquisition, high experimental costs, inconvenient change of working conditions, and complex operation when directly conducting experiments on the steam turbine.

[0004] Therefore, it is necessary to design a simulation device for the rubbing test of turbine shroud bands and a simulation method thereof to improve the deficiencies of the above-mentioned existing technologies. Summary of the Invention

[0005] The purpose of the present invention is to design a simulation device for the rubbing test of turbine shroud bands and a simulation method thereof, which are used to solve the technical problems of inconvenient data acquisition, high test cost, inconvenient change of test working conditions, and complex operation when directly conducting the rubbing test of the shroud band on the steam turbine.

[0006] The technical solution of the present invention:

[0007] A simulation device for the rubbing test of turbine shroud bands includes: an installation platform, a shroud band fixing device, a loading device, a vibration signal input system, and an experimental data acquisition system; the installation platform includes: a base, a crank handle clamp, and a T-shaped load-bearing plate; the crank handle clamp is arranged on the top of the base, one end of the shroud band fixing device is clamped and fixedly connected with the crank handle clamp, and the other end of the shroud band fixing device is fixed with a loading device; the vibration signal input system is arranged on one side of the base through the T-shaped load-bearing plate; a plurality of waist-shaped through holes are evenly distributed on the side of the base where the T-shaped load-bearing plate is arranged.

[0008] The shroud band fixing device further includes: a hole seat, a plurality of round rods, and a shroud band; a plurality of threaded through holes are evenly distributed on the hole seat, one end of the round rod passes through the mounting connection hole on the hole seat, and the other end of the round rod is connected with the shroud band.

[0009] The loading device includes: two Z-shaped rods, a load-bearing block, an adjustable-distance screw, a spring, a rod tightening member, two T-shaped limit blocks and two tightening straps, an adjustable-distance nut, and a number of double-headed screws and horizontal loading screws; the two Z-shaped rods are arranged in parallel side by side and fixedly connected by a number of double-headed screws, and the load-bearing block is arranged between the upper positions of the two Z-shaped rods and fixed by double-headed screws; a threaded through-hole is provided at the center of the load-bearing block; the adjustable-distance screw passes through the threaded through-hole at the center of the load-bearing block and is connected to one end of the spring, and the other end of the spring is connected to one end of the rod tightening member, and the other end of the rod tightening member is fixed on one of the round rods.

[0010] Two T-shaped limit blocks are horizontally placed at the lower positions of the two Z-shaped rods, and the two T-shaped limit blocks are connected by a horizontal loading screw; a tightening strap is sleeved on each T-shaped limit block and fixed on one of the round rods respectively.

[0011] The lengths of the number of double-headed screws match the distance between the two Z-shaped rods; four waist-shaped through-holes of the same size as the base are also provided on the upper surface of the T-shaped load-bearing plate, and the waist-shaped through-holes on the T-shaped load-bearing plate and the base are in corresponding positions and the T-shaped load-bearing plate is fixed on the side of the base by bolts.

[0012] The center lines of the adjustable-distance nut, the load-bearing block, the adjustable-distance screw, and the spring are on the same vertical line as the center line of the round rod fixed by the rod tightening member, and the center of each T-shaped limit block is on the same vertical line as the center of the corresponding fixed round rod.

[0013] The vibration signal input system further includes: an exciter, a power amplifier, and an oscilloscope; the experimental data acquisition system includes an eddy current displacement sensor, a signal pre-amplifier, a signal collector, and a computer.

[0014] The exciter is installed at the waist-shaped through-hole of the T-shaped load-bearing plate by bolts.

[0015] The exciter is in contact with the round rod.

[0016] The simulation method of any one of the steam turbine shroud rubbing test simulation devices as described above includes the following steps:

[0017] Step 1: First assemble the shroud fixing device and clamp it in the crank handle fixture above the base; then install the T-shaped load-bearing plate and the exciter on the base successively, and adjust the exciter to a suitable position by adjusting the waist-shaped through-hole during this period; then assemble the loading device and fix the T-shaped limit block and the round rod in the loading device by tightening straps.

[0018] Step 2: Install the eddy current displacement sensor at a suitable position and connect it to other devices of the vibration experiment data acquisition system, and connect the exciter to other devices of the signal input system; during the experiment, turn the distance adjusting nut to adjust the stretching amount of the spring, so as to apply a certain vertical force on the shroud, and obtain the magnitude of the vertical force from the number of turns of the distance adjusting nut and the spring parameters; turn the nut on the horizontal loading screw to apply a certain horizontal force, and detect the change of the shroud vibration parameters through the sensor to obtain the experimental basis for the shroud rubbing law.

[0019] Advantages of the present invention:

[0020] 1. The present invention designs a simulation device for turbine shroud rubbing test, which can effectively simulate the turbine shroud rubbing phenomenon, and is a compact experimental simulation device for shroud vibration rubbing phenomenon;

[0021] 2. The present invention can study the relationship between the magnitude of the axial force on the shroud and the rubbing vibration response of the shroud by adjusting the axial force of different magnitudes on the shroud;

[0022] 3. The present invention can adjust the circumferential force of different magnitudes on the shroud and study the relationship between this factor and the rubbing vibration response of the shroud;

[0023] 4. The present invention can be applied to the simulation test of the collision friction vibration between the working surfaces of turbine shrouds with different shapes and structures;

[0024] 5. The present invention can conduct different simulation tests of turbine shroud rubbing vibration by adjusting the clearance between the working surfaces of the turbine shroud. Description of the drawings

[0025] Figure 1 is a schematic structural diagram of the shroud rubbing test simulation device described in the present invention;

[0026] Figure 2 is a schematic structural diagram of the shroud fixing device described in the present invention;

[0027] Figure 3 is a schematic structural diagram of the loading device described in the present invention.

[0028] Wherein: 1 - shroud rubbing test simulation device; 2 - base; 3 - crank clamp; 4 - T-shaped load-bearing plate; 5 - waist-shaped through hole; 6 - shroud fixing device; 7 - loading device; 8 - vibration signal input system; 9 - exciter; 10 - hole seat; 11 - round rod; 12 - shroud; 13 - Z-shaped rod; 14 - load-bearing block; 15 - distance adjusting screw; 16 - spring; 17 - rod tightening member; 18 - distance adjusting nut; 19 - T-shaped limit block; 20 - horizontal loading screw; 21 - tightening belt; 22 - double-headed screw. Specific embodiments

[0029] The present invention will be further introduced below in conjunction with the accompanying drawings and embodiments:

[0030] The present invention is used for carrying out shroud rubbing experiments in the laboratory. By inputting vibration signals through a vibrator, collisions and frictions between two shrouds are made to simulate the rubbing of shrouds under actual working conditions. Different horizontal and vertical forces are applied to a round rod to change the magnitude and direction of the contact force between the shrouds, so as to explore the influence of the change of the contact force on the vibration response.

[0031] A simulation device for steam turbine shroud rubbing test, comprising: an installation platform, a shroud fixing device 6, a loading device 7, a vibration signal input system 8 and an experimental data acquisition system; the installation platform includes: a base 2, a crank handle clamp 3 and a T-shaped load-bearing plate 4; the crank handle clamp 3 is arranged on the top of the base 2, one end of the shroud fixing device 6 is clamped and fixedly connected with the crank handle clamp 3, and a loading device 7 is fixed on the other end of the shroud fixing device 6; the vibration signal input system 8 is arranged on one side of the base 2 through the T-shaped load-bearing plate 4; a plurality of waist-shaped through holes are evenly distributed on the side of the base 2 where the T-shaped load-bearing plate 4 is arranged.

[0032] The shroud fixing device 6 further includes: a hole seat 10, a plurality of round rods 11 and a shroud 12, a plurality of threaded through holes are evenly distributed on the hole seat 10, one end of the round rod 11 passes through the mounting through hole on the hole seat 10 to connect with the hole seat 10, and the other end of the round rod 11 is connected with the shroud 12.

[0033] The loading device 7 includes: two Z-shaped rods 13, a load-bearing block 14, an adjusting screw 15, a spring 16, a rod tightening band 17, two T-shaped limit blocks 19 and two tightening bands 21, an adjusting nut 18 and a plurality of double-headed screws 22 and a horizontal loading screw 20; the two Z-shaped rods 13 are arranged in parallel side by side and fixedly connected through a plurality of double-headed screws 22, the load-bearing block 14 is arranged between the upper positions of the two Z-shaped rods 13 and fixedly connected through a double-headed screw 22; a threaded through hole is arranged at the center of the load-bearing block 14; the adjusting screw 15 passes through the central threaded through hole of the load-bearing block 14 to be connected with one end of the spring 16, the other end of the spring 16 is connected with one end of the rod tightening band 17, and the other end of the rod tightening band 17 is fixed on one of the round rods 11.

[0034] Two T-shaped limit blocks 19 are horizontally placed at the lower positions of the two Z-shaped rods 13, and the two T-shaped limit blocks 19 are connected through a horizontal loading screw 20; a tightening band 21 is sleeved on each T-shaped limit block 19 and fixed on one of the round rods 11 respectively.

[0035] The lengths of the plurality of double-headed screws 22 match the distance between the two Z-shaped rods 13; four waist-shaped through holes of the same size as the base 2 are also provided on the upper surface of the T-shaped load-bearing plate 4. The waist-shaped through holes on the T-shaped load-bearing plate 4 and the base 2 are in corresponding positions and the T-shaped load-bearing plate 4 is fixed to the side of the base 2 by bolts.

[0036] The center lines of the adjusting nuts 18, the load-bearing blocks 14, the adjusting screws 15, and the springs 16 are on the same vertical line as the center line of the round rod 11 fixed by the rod tightener 17. The center of each T-shaped limit block 19 is on the same vertical line as the center of the corresponding fixed round rod 11.

[0037] The vibration signal input system 8 further includes: an exciter 9, a power amplifier, and an oscilloscope; the experimental data acquisition system includes an eddy current displacement sensor, a signal pre-amplifier, a signal collector, and a computer.

[0038] The exciter 9 is installed at the waist-shaped through hole of the T-shaped load-bearing plate 4 by bolts.

[0039] The top of the exciter 9 is in contact with the round rod 11; the rigidity of the round rod 11 on the shroud fixing device 6 in contact with the ejector rod of the exciter 9 is different from that of the other round rods 11. The round rod 11 in contact with the ejector rod of the exciter 9 is a flexible rod with a smaller stiffness.

[0040] The simulation method of any one of the steam turbine shroud rubbing test simulation devices as described above includes the following steps:

[0041] Step 1: First, assemble the shroud fixing device 6 and clamp it in the crank handle fixture 3 above the base 2; then install the T-shaped load-bearing plate 4 and the exciter 9 on the base 2 successively. During this period, adjust the position of the exciter 9 to a suitable position by adjusting the waist-shaped through hole 5; then assemble the loading device 7 and fix the T-shaped limit block in the loading device 7 to the round rod 11 through the tightening belt 21.

[0042] Step 2: Install the eddy current displacement sensor at a suitable position and connect it to other devices of the vibration experiment data acquisition system. Connect the exciter 9 to other devices of the signal input system 8; during the experiment, rotate the adjusting nut 18 to adjust the stretching amount of the spring 16, so as to apply a certain vertical force to the shroud 12. Obtain the magnitude of the vertical force from the number of turns of the adjusting nut 18 and the parameters of the spring 16; rotate the nut on the horizontal loading screw 21 to apply a certain horizontal force, and detect the change of the shroud vibration parameters through the sensor to obtain the experimental basis for the shroud rubbing law.

[0043] The loading device 7 uses two Z-shaped rods instead of a large Z-shaped rod, which not only saves steel materials but also reduces the weight of the loading device and the influence of the loading device on the shroud vibration response.

[0044] By rotating the distance-adjusting nut 18 to stretch the spring 16, a vertical force is generated. The vertical force is transmitted through the Z-shaped rod and the round rod and finally acts on the shroud. The horizontal force is applied by rotating the nut on the horizontal loading screw to change the distance between the two middle round rods, thereby loading a certain horizontal force onto the shroud. Under the condition of fully considering the actual rubbing of the shroud, this device simulates the actual working conditions, and the detected data has high application value.

[0045] The present invention has been described in detail above in conjunction with the accompanying drawings and embodiments. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the gist of the present invention. The content not described in detail in the present invention can all adopt the prior art.

Claims

1. A simulation device for the rubbing of turbine shroud bands, characterized in that, it includes: an installation platform, a shroud band fixing device (6), a loading device (7), a vibration signal input system (8) and an experimental data acquisition system; the installation platform includes: a base (2), a crank handle clamp (3) and a T-shaped load-bearing plate (4); the crank handle clamp (3) is arranged on the top of the base (2), one end of the shroud band fixing device (6) is clamped and fixedly connected with the crank handle clamp (3), and a loading device (7) is fixed on the other end of the shroud band fixing device (6); the vibration signal input system (8) is arranged on one side of the base (2) through the T-shaped load-bearing plate (4); a number of waist-shaped through holes are evenly distributed on the side of the base (2) where the T-shaped load-bearing plate (4) is arranged.

2. The simulation device for the rubbing of turbine shroud bands according to claim 1, characterized in that: the shroud band fixing device (6) further includes: a hole seat (10), a number of round rods (11) and a shroud band (12), a number of threaded through holes are evenly distributed on the hole seat (10), one end of the round rod (11) passes through the installation connection hole on the hole seat (10) to connect with the hole seat (10), and the other end of the round rod (11) is connected with the shroud band (12).

3. The simulation device for the rubbing of turbine shroud bands according to claim 2, characterized in that: the loading device (7) includes: two Z-shaped rods (13), a bearing block (14), an adjustable distance screw (15), a spring (16), a rod tightening hoop (17), two T-shaped limit blocks (19) and two tightening bands (21), an adjustable distance nut (18) and a number of double-headed screws (22) and a horizontal loading screw (20); the two Z-shaped rods (13) are arranged in parallel and fixedly connected through a number of double-headed screws (22), the bearing block (14) is arranged between the upper positions of the two Z-shaped rods (13) and fixed through a double-headed screw (22); a threaded through hole is arranged at the center of the bearing block (14); the adjustable distance screw (15) passes through the central threaded through hole of the bearing block (14) to be connected with one end of the spring (16), the other end of the spring (16) is connected with one end of the rod tightening hoop (17), and the other end of the rod tightening hoop (17) is fixed on one of the round rods (11).

4. The simulation device for the rubbing of turbine shroud bands according to claim 3, characterized in that: two T-shaped limit blocks (19) are horizontally placed at the lower positions of the two Z-shaped rods (13), and the two T-shaped limit blocks (19) are connected through a horizontal loading screw (20); a tightening band (21) is sleeved on each T-shaped limit block (19) and fixed on one of the round rods (11) respectively.

5. The simulation device for the rubbing of turbine shroud bands according to claim 4, characterized in that: The lengths of the several double-headed screws (22) match the distance between the two Z-shaped rods (13); four waist-shaped through holes of the same size as the base (2) are also provided on the upper surface of the T-shaped load-bearing plate (4). The waist-shaped through holes on the T-shaped load-bearing plate (4) and the base (2) are correspondingly matched in position, and the T-shaped load-bearing plate (4) is fixed to the side of the base (2) by bolts.

6. A steam turbine shroud rubbing test simulation device according to claim 5, characterized in that: The center lines of the adjusting nut (18), the bearing block (14), the adjusting screw (15), and the spring (16) are on the same vertical line as the center line of the round rod (11) fixed by the rod tightener (17). The center of each T-shaped limit block (19) is on the same vertical line as the center of the corresponding fixed round rod (11).

7. A steam turbine shroud rubbing test simulation device according to claim 6, characterized in that: The vibration signal input system (8) further includes: an exciter (9), a power amplifier, and an oscilloscope; the experimental data acquisition system includes an eddy current displacement sensor, a signal pre-amplifier, a signal collector, and a computer.

8. A steam turbine shroud rubbing test simulation device according to claim 7, characterized in that: The exciter (9) is installed at the waist-shaped through hole of the T-shaped load-bearing plate (4) by bolts.

9. A steam turbine shroud rubbing test simulation device according to claim 8, characterized in that: The top of the exciter (9) is in contact with the round rod (11).

10. A simulation method of any one of the steam turbine shroud rubbing test simulation devices according to claims 1 to 9, characterized in that it includes the following steps: Step 1: First assemble the shroud fixing device (6) and clamp it in the crank handle clamp (3) above the base (2); then install the T-shaped load-bearing plate (4) and the exciter (9) on the base (2) successively. During this period, adjust the exciter (9) to a suitable position by adjusting the waist-shaped through hole (5); then assemble the loading device (7) and fix the T-shaped limit block in the loading device (7) to the round rod (11) through the tightening belt (21). Step 2: Install the eddy current displacement sensor in a suitable position and connect it to other devices of the vibration experiment data acquisition system. Connect the exciter (9) to other devices of the signal input system (8); during the experiment, rotate the adjusting nut (18) to adjust the stretching amount of the spring (16), so as to apply a certain vertical force to the shroud (12). Obtain the magnitude of the vertical force from the number of turns of the adjusting nut (18) and the parameters of the spring (16); rotate the nut on the horizontal loading screw (21) to apply a certain horizontal force. Detect the change of the shroud vibration parameters through the sensor to obtain the experimental basis for the shroud rubbing law.

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