A sand blasting device for surface repair of a water turbine flow passage component and a method of using the same

Abstract

The application discloses a sand blasting device for surface repair of a water turbine flow part and a use method thereof, and relates to the technical field of water turbine repair, which comprises a shape seat, a probe sand blasting unit, a torsion flat scanning unit and a workpiece lifting unit. The probe sand blasting unit comprises a bottom ring, an upper ring, an elastic flexible pipe, a mounting block, a sand blasting head and a reserved joint. In the application, the lowering process of the runner workpiece can make the upper ring move downward after being pressed by the linkage pressure rod, and the elastic flexible pipe is extruded. Since the elastic flexible pipe is obliquely arranged, it can arch inward after being pressed from the upper side, and then drive the sand blasting head into the narrow gap of the runner blade, so that the sand blasting treatment is effectively performed on the front and back surfaces of the blade. When the subsequent workpiece moves upward and out, the elastic flexible pipe restores to be straight, and the mounting block carries the sand blasting head to automatically move outward, so that the movement of the runner workpiece is not affected.

Description

Technical Field

[0001] This invention relates to the field of water turbine maintenance technology, specifically to a sandblasting device for surface repair of water turbine flow components and its usage method. Background Technology

[0002] The Biedeli and Yamansu hydropower stations are two important hydropower stations in my country, significantly alleviating the power shortage in southern Xinjiang and providing great assistance to national development and daily life. However, due to the high sediment content in the turbines during the flood season, the turbine components suffer from severe wear and erosion damage, requiring extensive repairs annually, making it difficult to guarantee normal operation during the flood season. Furthermore, the heat input from frequent welding repairs increases residual stress in the substrate, weakening material properties and further reducing the unit's corrosion resistance. This project proposes to adopt the AC-HVAF spray coating protection technology (a technology promoted and applied in the Advanced Technology Promotion and Application Catalog) to modify and protect the surface of the flow components, effectively improving their corrosion resistance, extending their service life, and enhancing the unit's operational safety. The prior art disclosed in application number 201520265569.0 is a dust-free sandblasting device for narrow-gap deep-hole pipe fittings. It uses an I-shaped semi-circular ring double-layer structure for dust sealing. The I-shaped semi-circular ring double-layer structure is fixed by hinges and butterfly nuts, which makes installation convenient and quick, and realizes sandblasting of deep-hole narrow-gap pipe fittings. However, while its device solves the problem of sandblasting inside pipes, the internal structure of the turbine's core component—the runner—is more complex. The gaps between adjacent blades are not only narrow but also curved, making it difficult for the sandblasting device to enter. Some extended sandblasting devices lack reliable linkage support and are not timely enough when the runner workpiece is sandblasted and withdrawn, easily colliding with the edge of the runner workpiece and causing damage to the sandblasting device. Therefore, we propose a sandblasting device for surface repair of turbine flow components and its specific usage method. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the existing defects and provide a sandblasting device and its usage method for surface repair of turbine flow components. During the lowering of the runner workpiece, the upper ring moves downward under the pressure of the linkage pressure rod, causing compression of the elastic flexible tube. Because the elastic flexible tube is obliquely set, it can arch inward under the pressure from the upper side, thereby driving the sandblasting head into the narrow gap of the runner blade, thus effectively sandblasting the front and back surfaces of the blade. When the workpiece is subsequently moved upward, the elastic flexible tube returns to its straight position, and the mounting block carrying the sandblasting head automatically withdraws outward, thus not affecting the removal of the runner workpiece, which can effectively solve the problems in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a sandblasting device for surface repair of turbine flow components, comprising an annular seat, a penetration sandblasting unit, a torsional flat sweeping unit, and a workpiece lifting unit; Annular seat: Located at the bottom of the device; The insertion sandblasting unit includes a bottom ring, an upper ring, flexible flexible tubes, mounting blocks, sandblasting heads, and pre-installed connectors. The bottom ring is parallel to the top of the annular seat, and the upper ring is parallel to the top of the bottom ring. The centers of the annular seat, the bottom ring, and the upper ring are located on the same vertical axis. The diameter of the upper ring is larger than that of the bottom ring but smaller than that of the annular seat. The opposite ends of the upper and bottom rings are chamfered bevels, and each chamfered bevel has a ring of pre-installed connectors. Fifteen inclined flexible flexible tubes are connected in a ring array between the upper and bottom rings. The two ends of the flexible flexible tubes are connected to the pre-installed connectors on the opposite sides of the bottom and upper rings through a screw connector. A U-shaped mounting block is installed in the middle section of each flexible flexible tube, and a sandblasting head is installed on both sides of the mounting block. Torsional sweeping unit: installed inside the annular seat and on the upper right side; Workpiece lifting unit: installed directly above the upper ring.

[0005] The bottom ring is fixed in position by the tray. The upper ring is larger in diameter than the bottom ring, allowing the lower end of the flexible tube to tilt inward and converge during installation. The upper ring moves downward under the pressure of the linkage rod, squeezing the flexible tube. Due to the oblique setting of the flexible tube, it can arch inward under the pressure from the upper side, thereby driving the sandblasting head into the narrow gap of the rotor blades, thus effectively sandblasting the front and back surfaces of the blades. As the workpiece moves upward, the flexible tube returns to its straight position, and the mounting block carrying the sandblasting head automatically withdraws outward, thus not affecting the upward movement of the rotor workpiece.

[0006] Furthermore, the insertion sandblasting unit also includes vertical guide rods, connecting blocks, limiting blocks, and springs. Four vertical guide rods are fixedly connected to the upper end of the annular seat. Four connecting blocks are fixedly connected to the outer circumference of the upper ring. The four connecting blocks are arranged in a square diagonally and are slidably connected to one of the vertical guide rods. Two limiting blocks are fixedly connected to the upper part of the vertical guide rods, and a spring is set between the two limiting blocks. The spring is sleeved on the outer side of the vertical guide rod, and the connecting block presses against the upper end of the spring. The vertical guide rods guide the upper ring during lifting and lowering. The connecting blocks connect the upper ring and the vertical guide rods. The limiting blocks are used for spring installation and prevent the connecting blocks from slipping off the upper end of the vertical guide rods. The springs provide assistance when the upper ring resets and maintain the initial position of the upper ring, ensuring that the elastic flexible tube is taut when the workpiece enters.

[0007] Furthermore, the workpiece lifting unit includes a hydraulic cylinder, lifting brackets, and a lifting electromagnet. The hydraulic cylinder body is vertically positioned and connected to an external hydraulic source. The telescopic rod of the hydraulic cylinder points vertically downwards and coincides with the axis of the center of the annular seat, the bottom ring, and the upper ring. A lifting electromagnet is fixedly installed at the lower end of the telescopic rod. Four approximately Z-shaped lifting brackets are arranged in a circular array around the outer circumference of the hydraulic cylinder body. The lower end of the lifting brackets supports the lower side of the hydraulic cylinder body, and the upper end of the lifting brackets has bolt through holes for fixing to the wall or external frame with bolts. The lifting brackets are used for the installation and securing of the hydraulic cylinder. By adding bolts to the ends of the lifting brackets, the hydraulic cylinder can be installed and fixed to the wall or external frame. When the lifting electromagnet is energized, it generates an attraction effect on the rotating workpiece, which, in conjunction with the hydraulic cylinder, completes the lowering and removal of the workpiece.

[0008] Furthermore, the workpiece lifting unit also includes linkage pressure rods. Four horizontal linkage pressure rods are arranged in a cross shape on the outside of the hydraulic cylinder telescopic rod, and a ring is fixedly connected to the inner end of each rod. The ring fits around the outside of the hydraulic cylinder telescopic rod and is secured with bolts. The linkage pressure rods apply pressure to the upper ring while the workpiece is being lowered from the rotating wheel, causing it to move downwards and compress the elastic flexible connecting pipe, bending it inwards. This allows the sandblasting head to enter the gaps in the rotating wheel blades simultaneously with the workpiece being lowered.

[0009] Furthermore, the penetration sandblasting unit also includes a locking block, fixing bolts, retaining rings, and elastic ribs. The U-shaped mounting block is locked onto the outside of the elastic flexible tube. A slender elastic rib is fixedly connected to the inner side of the elastic flexible tube. Circular retaining rings are fixedly connected to the ends and middle section of the elastic rib, securing it to the outside of the elastic flexible tube. Square through holes are provided on both the left and right sides of the mounting block. The locking block has a U-shaped structure, with both ends inserted into the square through holes on the side of the mounting block. Two fixing bolts are threaded onto the open side of the mounting block, and the threaded shaft of the fixing bolts presses the locking block against the elastic flexible tube. By tightening the fixing bolts, the locking block and the mounting block can be clamped relative to each other on the outside of the elastic flexible tube, thereby fixing the mounting block in the middle section of the elastic flexible tube. The elastic rib is held tightly to the elastic flexible tube by the retaining rings and provides restoring force support when the elastic flexible tube returns to its straight position.

[0010] Furthermore, the penetration sandblasting unit also includes a three-way connector, solenoid valves, and a PLC controller. Four right-angled locking blocks are fixedly connected to both sides of the mounting block, securing them to the four corners of the sandblasting head. The sandblasting head has a rectangular structure with a long, narrow nozzle on its outer side. The nozzle's upper and lower ends flare outwards in a V-shape, and the internal channel has rounded corners near the center of the device. A three-way connector is connected to one of the outer ends of the sandblasting head. A solenoid valve is installed at each of the two inlets of the three-way connector. A small PLC controller is installed at the corner of the mounting block, and the two solenoid valves are electrically connected to an external power supply via the PLC controller. The three-way connector is used for the connection of air and sand sources, the solenoid valves control the opening and closing of the three-way connector, and the PLC controller automatically controls the opening and closing of the two inlets of the three-way connector based on the electrical signals from the sensors.

[0011] Furthermore, the penetration sandblasting unit also includes a light sensor and a distance sensor. A light sensor is installed on the upper edge of the mounting block, and a distance sensor is installed at the center of the square end face of the mounting block. Both the light sensor and the distance sensor are connected to an external power supply via a PLC controller. The light sensor is installed on the upper inner edge of the mounting block. When it enters the gap inside the rotary workpiece, it generates a signal change when blocked by the upper side of the workpiece, which can then cooperate with the PLC controller to automatically control the opening of two solenoid valves. The distance sensor is used to monitor the distance between the mounting block and the center of the rotary workpiece in real time. When the mounting block reaches the middle position of the blade gap, and the rotary workpiece descends to a point where its midline is slightly lower than the vertical height of the sandblasting head, the workpiece's descent stops, and the sandblasting head stops at the middle depth of the blade gap.

[0012] Furthermore, the torsional sweeping unit includes a toothed belt, a servo motor, and a gear. A section of the toothed belt is fixedly connected to the arc segment area corresponding to a continuous 60° central angle on the right side of the outer circumference of the bottom ring. The servo motor is mounted and fixed on the upper right side of the ring seat, and the upper end of the servo motor is rotatably connected to the gear, which meshes with the toothed belt. When the servo motor starts, the meshing effect between the gear and the toothed belt can drive the bottom ring to rotate. The controller of the servo motor can realize alternating forward and reverse rotation at a certain angle. The rotation of the bottom ring will bring a torsional effect to the elastic flexible tube, thereby driving the sandblasting head to rotate horizontally, thus performing a horizontal reciprocating sweeping sandblasting action to ensure that there are no dead angles in the sandblasting.

[0013] Furthermore, the torsional flat sweeping unit also includes a bracket and a tray. The bracket is fixedly connected inside the annular seat, and consists of a bottom cross-shaped connecting rod and a central support column. A tray is fixedly connected to the upper end of the bracket. The edge of the tray has a stepped structure. The upper end of the tray is inserted into and rotatably connected to the inside of the bottom ring, and the lower end of the tray rests on the lower side of the bottom ring. The bracket is used for tray installation. The stepped edge of the tray can support and limit the bottom ring, ensuring that the elastic flexible connecting tube can deform under pressure from the upper side. The upper end of the tray, inserted into and rotatably connected to the inside of the bottom ring, can provide a horizontal fixed-point limiting effect on the bottom ring, allowing it to rotate stably.

[0014] A method for using a sandblasting device for surface repair of flow components in a water turbine, the specific steps of which are as follows: S1): First, tighten the screw joints at both ends of the flexible hose to the reserved joints on the opposite side of the bottom ring and the upper ring. Then, install the U-shaped mounting block with the opening facing outward on the outside of the flexible hose and tighten the fixing bolts so that the locking block and the mounting block are locked together on the outside of the flexible hose, thus completing the installation and fixing of the sandblasting head in the middle section of the flexible hose. S2): Then connect the two inlet ends of the three-way connector to the external air source and sand source respectively with soft material conveying pipes, and connect the two solenoid valves, light sensor and distance sensor to the PLC controller on each side. Set the parameters at the PLC controller so that when the light sensor detects that the light is blocked by the workpiece to be repaired, the two solenoid valves can be automatically opened by the PLC controller to realize the connection of the external air source and sand source.

[0015] S3): Activate the lifting electromagnet and fix the wheel workpiece to be repaired horizontally to the lower side of the lifting electromagnet. Then activate the hydraulic cylinder to lower the lifting electromagnet carrying the wheel workpiece between the elastic flexible tubes of the ring array. The linkage pressure rod will press on the upper ring, which will push the upper ring to slide down along the vertical guide rod, squeezing the elastic flexible tube and causing it to arch inward. This will drive the sandblasting head into the narrow gap of the wheel blades to sandblast the blade surface. The distance sensor monitors the distance between the mounting block and the center of the wheel workpiece in real time. When the mounting block reaches the middle position of the blade gap and the wheel workpiece descends to a position where its center line is slightly lower than the vertical height of the sandblasting head, the downward movement of the workpiece is stopped. S4): After the sandblasting head enters the narrow gap between the rotor blades, the servo motor is started to reciprocate in both directions at a certain angle, driving the bottom ring to rotate in both directions at the corresponding angle. The rotation of the bottom ring will bring a torsional effect to the flexible hose, which in turn drives the sandblasting head to rotate horizontally, thereby performing a horizontal reciprocating sweeping sandblasting action to ensure that there are no dead angles in the sandblasting contact. The sandblasting heads on both sides sandblast and repair the surface of the adjacent blades. After the repair is completed, the hydraulic cylinder drives the workpiece to move upward and reset. During this process, the flexible hose returns to its straight position, and the mounting block carrying the sandblasting head automatically withdraws outward without affecting the upward movement of the rotor workpiece.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: The sandblasting device and its method for repairing the surface of the flow components of a water turbine have the following advantages: 1. During the lowering of the workpiece on the rotor, the upper ring moves downward under the pressure of the linkage rod, squeezing the elastic flexible tube. Due to the oblique setting of the elastic flexible tube, it can arch inward under the pressure from the upper side, thereby driving the sandblasting head into the narrow gap of the rotor blade, thus effectively sandblasting the front and back surfaces of the blade; as the workpiece moves upward, the elastic flexible tube returns to its straight position, and the mounting block carrying the sandblasting head automatically retracts outward, thus not affecting the upward movement of the workpiece on the rotor. 2. When the lifting electromagnet is energized, it attracts the workpiece to the rotating wheel, which works in conjunction with the hydraulic cylinder to lower and remove the workpiece. The vertical guide rod guides the upper ring during lifting and lowering. During removal, the spring assists in the upper ring's reset and maintains its initial position, ensuring that the elastic flexible tube is taut when the workpiece enters. The elastic ribs are held tightly to the elastic flexible tube by snap rings and provide restoring force when the elastic flexible tube returns to its straight position. 3. When the sandblasting head enters the middle depth of the blade gap, the servo motor starts working. Through the meshing effect between the gear and the toothed belt, the bottom ring is rotated. The controller of the servo motor can realize the alternating rotation of a certain angle in both directions. The rotation of the bottom ring will bring a torsional effect to the elastic soft tube, which in turn drives the sandblasting head to rotate horizontally, thereby performing a horizontal reciprocating sweeping sandblasting action to ensure that there are no dead angles in the sandblasting contact. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a cross-sectional view of a partial structure of the present invention; Figure 3 This is a schematic diagram of the installation of the mounting block in this invention; Figure 4 This is a schematic diagram of the structure of the sandblasting head in this invention; Figure 5 For the present invention Figure 2 Enlarged view of the structure at point A in the middle.

[0018] In the diagram: 1. Ring seat, 2. Insertion sandblasting unit, 21. Bottom ring, 22. Upper ring, 23. Elastic flexible connecting pipe, 24. Mounting block, 25. Sandblasting head, 26. Vertical guide rod, 27. Connecting block, 28. Limiting block, 29. Spring, 210. Locking block, 211. Fixing bolt, 212. Snap ring, 213. Three-way valve, 214. Solenoid valve, 215. PLC controller, 216. Light sensor, 217. Distance sensor, 218. Elastic rib, 219. Reserved connector, 3. Torsional sweeping unit, 31. Toothed belt, 32. Servo motor, 33. Actuating gear, 34. Bracket, 35. Pallet, 4. Workpiece lifting unit, 41. Hydraulic cylinder, 42. Lifting clamp, 43. Lifting electromagnet, 44. Linkage pressure rod. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figures 1-5 This embodiment provides a technical solution: a sandblasting device for surface repair of turbine flow components, including an annular seat 1, a penetration sandblasting unit 2, a torsional flat sweeping unit 3, and a workpiece lifting unit 4; Annular seat 1: Located at the bottom of the device; The insertion sandblasting unit 2 includes a bottom ring 21, an upper ring 22, a flexible flexible tube 23, a mounting block 24, a sandblasting head 25, and a reserved connector 219. The bottom ring 21 is arranged parallel to the top of the annular seat 1, and the upper ring 22 is arranged parallel to the top of the bottom ring 21. The centers of the annular seat 1, the bottom ring 21, and the upper ring 22 are located on the same vertical axis. The diameter of the upper ring 22 is larger than the diameter of the bottom ring 21, but smaller than the diameter of the annular seat 1. The upper ring 22 and the bottom ring 21 are aligned. Both ends are chamfered bevels, and both chamfered bevels are circumferentially arrayed with a reserved connector 219. Fifteen oblique flexible flexible tubes 23 are connected in a ring array between the upper ring 22 and the bottom ring 21. The two ends of the flexible flexible tubes 23 are respectively connected to the reserved connectors 219 on the opposite side of the bottom ring 21 and the upper ring 22 through a screw connector. A U-shaped mounting block 24 is installed in the middle section of each flexible flexible tube 23. A sandblasting head 25 is installed on both sides of the mounting block 24. Torsional flat sweeping unit 3: installed inside the annular seat 1 and on the upper right side; Workpiece lifting unit 4: installed directly above the upper ring 22.

[0021] The bottom ring 21 is fixed in position under the action of the tray 35. The upper ring 22 is larger than the diameter of the bottom ring 21, so that the lower end of the elastic flexible tube 23 can tilt inward and converge during installation. After being pressured by the linkage pressure rod 44, the upper ring 22 moves downward and squeezes the elastic flexible tube 23. Since the elastic flexible tube 23 is set at an angle, it can arch inward after being pressured from the upper side, thereby driving the sandblasting head 25 into the narrow gap of the rotor blade, thus effectively sandblasting the front and back surfaces of the blade. When the workpiece moves upward, the elastic flexible tube 23 returns to straight, and the mounting block 24 carries the sandblasting head 25 to automatically withdraw outward, thus not affecting the upward movement of the rotor workpiece.

[0022] The insertion sandblasting unit 2 also includes vertical guide rods 26, connecting blocks 27, limiting blocks 28, and springs 29. Four vertical guide rods 26 are fixedly connected to the upper end of the annular seat 1. Four connecting blocks 27 are fixedly connected to the outer circumference of the upper ring 22. The four connecting blocks 27 are arranged in a square diagonally and are slidably connected to one of the vertical guide rods 26 respectively. Two limiting blocks 28 are fixedly connected to the upper part of the vertical guide rods 26. A spring 29 is set between the two limiting blocks 28. The spring 29 is sleeved on the outer side of the vertical guide rods 26, and the connecting blocks 27 press against the upper end of the spring 29. The vertical guide rod 26 serves as a guide when the upper ring 22 is raised or lowered. The connecting block 27 is used to connect the upper ring 22 and the vertical guide rod 26. The limiting block 28 is used to install the spring 29 and prevents the connecting block 27 from slipping off the upper end of the vertical guide rod 26. The spring 29 can provide assistance when the upper ring 22 is reset and maintain the initial position of the upper ring 22, ensuring that the elastic soft tube 23 is in a taut state when the workpiece enters.

[0023] The workpiece lifting unit 4 includes a hydraulic cylinder 41, a lifting bracket 42, and a lifting electromagnet 43. The cylinder body of the hydraulic cylinder 41 is vertically arranged and connected to an external hydraulic source. The telescopic rod of the hydraulic cylinder 41 is vertically downward and coincides with the axis of the center of the three circles of the annular seat 1, the bottom ring 21, and the upper ring 22. The lifting electromagnet 43 is installed and fixed at the lower end of the telescopic rod. Four approximately Z-shaped lifting brackets 42 are arranged in a circular array on the outer circumference of the cylinder body of the hydraulic cylinder 41. The lower end of the lifting bracket 42 supports the lower side of the cylinder body of the hydraulic cylinder 41. The upper end of the lifting bracket 42 has bolt through holes and is fixed to the wall top or external frame with bolts. The lifting bracket 42 is used for the installation and securing of the hydraulic cylinder 41. By adding bolts to the end of the lifting bracket 42, the hydraulic cylinder can be installed and fixed on the top of the wall or on the external frame. When the lifting electromagnet 43 is energized, it generates an adsorption effect on the rotating workpiece, which works with the hydraulic cylinder 41 to complete the lowering and removal of the workpiece.

[0024] The workpiece lifting unit 4 also includes linkage pressure rods 44. Four horizontal linkage pressure rods 44 are arranged in a cross shape on the outside of the telescopic rod of the hydraulic cylinder 41. A ring is fixedly connected to the inner end of each linkage pressure rod, which fits around the outside of the telescopic rod of the hydraulic cylinder 41 and is fixed with bolts. The linkage pressure rods 44 can apply pressure to the upper ring 22 while the workpiece is being lowered on the rotating wheel, causing it to move downward and compress the elastic flexible connecting pipe 23, which bends and arches inward. This allows the sandblasting head 25 to enter the gap of the rotating wheel blades while the workpiece is being lowered.

[0025] The insertion sandblasting unit 2 also includes a locking block 210, fixing bolts 211, retaining rings 212, and elastic ribs 218. The U-shaped mounting block 24 is locked on the outside of the elastic flexible tube 23. A thin elastic rib 218 is fixedly connected to the inner side of the elastic flexible tube 23. The ends and the middle section of the elastic rib 218 are fixedly connected to circular retaining rings 212. The retaining rings 212 are locked on the outside of the elastic flexible tube 23. Square through holes are opened on both the left and right sides of the mounting block 24. The locking block 210 has a U-shaped structure, and its two ends are inserted into the square through holes on the side of the mounting block 24. Two fixing bolts 211 are threadedly connected to the open side of the mounting block 24. The threaded shaft of the fixing bolts 211 presses the locking block 210 against the elastic flexible tube 23. By tightening the fixing bolt 211, the locking block 210 and the mounting block 24 can be clamped relative to each other on the outside of the elastic flexible tube 23, thereby fixing the mounting block 24 in the middle section of the elastic flexible tube 23; the elastic rib 218 is held tightly to the elastic flexible tube 23 by the retaining ring 212, and provides support for the restoring force when the elastic flexible tube 23 returns to straight.

[0026] The sandblasting unit 2 also includes a three-way connector 213, a solenoid valve 214, and a PLC controller 215. Four right-angled blocks are fixedly connected to both sides of the mounting block 24. The right-angled blocks are fixed to the four corners of the sandblasting head 25. The sandblasting head 25 has a rectangular structure and an elongated nozzle on its outer side. The upper and lower ends of the nozzle are V-shaped and flared outwards. The corner of its internal channel near the middle of the device is rounded. A three-way connector 213 is connected to the outer end of the sandblasting head 25. A solenoid valve 214 is installed at each of the two inlet ends of the three-way connector 213. A small PLC controller 215 is installed at the corner of the mounting block 24. The two solenoid valves 214 are electrically connected to an external power supply through the PLC controller 215. The three-way connector 213 is used for the connection of air source and sand source. The solenoid valve 214 is used to control the opening and closing of the three-way connector 213. It is equipped with a PLC controller 215 to realize the automatic control of the opening and closing of the two inlet ends of the three-way connector 213 according to the electrical signal of the sensor.

[0027] The penetration sandblasting unit 2 also includes a light sensor 216 and a distance sensor 217. The light sensor 216 is installed on the upper edge of the mounting block 24, and the distance sensor 217 is installed at the center of the square end face of the mounting block 24. The light sensor 216 and the distance sensor 217 are also connected to an external power supply through the PLC controller 215. The light sensor 216 is installed on the upper inner edge of the mounting block 24. When it enters the gap inside the rotary workpiece, it generates a signal change when it is blocked by the upper side of the workpiece. This signal can then be used in conjunction with the PLC controller 215 to automatically control the opening of the two solenoid valves 214. The distance sensor 217 is used to monitor the distance between the mounting block 24 and the center of the rotary workpiece in real time. When the mounting block 24 reaches the middle position of the blade gap and the rotary workpiece descends to a point where its midline is slightly lower than the vertical height of the sandblasting head 25, the descent of the workpiece is stopped, and the sandblasting head 25 stops at the middle depth of the blade gap.

[0028] The torsional sweeping unit 3 includes a toothed belt 31, a servo motor 32, and a gear 33. A section of the toothed belt 31 is fixedly connected to the arc segment area corresponding to a continuous 60° central angle on the right side of the outer circumference of the bottom ring 21. The servo motor 32 is fixedly mounted on the upper right side of the ring seat 1. The upper end of the servo motor 32 is rotatably connected to the gear 33, which meshes with the toothed belt 31. Protective covers are installed on the outer sides of the gear 33 and the toothed belt 31. When the servo motor 32 is started, the meshing effect between the gear 33 and the toothed belt 31 can drive the bottom ring 21 to rotate. The controller of the servo motor 32 can realize alternating forward and reverse rotation at a certain angle. The rotation of the bottom ring 21 will bring a torsional effect to the elastic flexible tube 23, thereby driving the sandblasting head 25 to rotate horizontally, thus performing a horizontal reciprocating sweeping sandblasting action to ensure that there are no dead angles in the sandblasting contact.

[0029] The torsional flat sweeping unit 3 also includes a bracket 34 and a tray 35. The bracket 34 is fixedly connected inside the annular seat 1. The bracket 34 consists of a bottom cross-shaped connecting rod and a central support column. The tray 35 is fixedly connected to the upper end of the bracket 34. The edge of the tray 35 has a stepped structure. The upper end of the tray 35 is inserted into and rotatably connected to the inside of the bottom ring 21, and the lower end of the tray 35 rests on the lower side of the bottom ring 21. The bracket 34 is used for mounting the tray 35. The stepped edge of the tray 35 can support and limit the bottom ring 21, ensuring that the elastic soft tube 23 can deform under pressure from the upper side. The upper end of the tray 35 is inserted into and rotatably connected to the inside of the bottom ring 21, which can provide a horizontal fixed-point limiting effect for the bottom ring 21, allowing it to rotate stably.

[0030] A method for using a sandblasting device for surface repair of flow components in a water turbine, comprising the following steps: S1: First, screw the screw joints at both ends of the flexible flexible tube 23 to the reserved joints 219 on the opposite side of the bottom ring 21 and the upper ring 22. Then, install the U-shaped mounting block 24 with the opening facing outward on the outside of the flexible flexible tube 23 and tighten the fixing bolts 211 so that the locking block 210 and the mounting block 24 are locked together on the outside of the flexible flexible tube 23, thus completing the installation and fixing of the sandblasting head 25 in the middle section of the flexible flexible tube 23. S2: Then connect the two inlet ends of the three-way connector 213 to the external air source and the sand source respectively with soft material conveying pipes, and connect the two solenoid valves 214, the light sensor 216, and the distance sensor 217 to the PLC controller 215 on each side. Set the parameters at the PLC controller 215 so that when the light sensor 216 detects that the light is blocked by the workpiece to be repaired, the two solenoid valves 214 can be automatically opened through the PLC controller 215 to realize the connection of the external air source and the sand source.

[0031] S3: Start the lifting electromagnet 43 and fix the wheel workpiece to be repaired horizontally to the lower side of the lifting electromagnet 43. Then start the hydraulic cylinder 41 to make the lifting electromagnet 43 carry the wheel workpiece down to the elastic soft tube 23 of the ring array. The linkage pressure rod 44 will press on the upper ring 22, and then push the upper ring 22 to slide down along the vertical guide rod 26, which will squeeze the elastic soft tube 23, causing the elastic soft tube 23 to arch inward, and drive the sandblasting head 25 into the narrow gap of the wheel blades to sandblast the blade surface. The distance sensor 217 monitors the distance between the mounting block 24 and the center of the wheel workpiece in real time. When the mounting block 24 reaches the middle position of the blade gap and the wheel workpiece descends to a position where its middle line is slightly lower than the vertical height of the sandblasting head 25, the downward movement of the workpiece is stopped. S4: After the sandblasting head 25 enters the narrow gap between the rotor blades, the servo motor 32 is started to reciprocate in both directions at a certain angle, driving the bottom ring 21 to rotate in both directions at the corresponding angle. The rotation of the bottom ring 21 will bring a torsional effect to the elastic flexible tube 23, thereby driving the sandblasting head 25 to rotate horizontally, thus performing a horizontal reciprocating sweeping sandblasting action to ensure that there are no dead angles in the sandblasting contact. The sandblasting heads 25 on both sides sandblast and repair the surface of the adjacent blades. After the repair is completed, the hydraulic cylinder 41 drives the workpiece to move upward and reset. During this process, the elastic flexible tube 23 returns to its straight position, and the mounting block 24 carries the sandblasting head 25 to automatically withdraw outward without affecting the upward movement of the rotor workpiece.

[0032] It is worth noting that, in the above embodiments, the input terminals of the solenoid valve 214 and the light sensor 216 are electrically connected to the output terminal of the external power supply through a small PLC controller 215. The input terminals of the servo motor 32 controller, the hydraulic cylinder 41 power unit connected to the external hydraulic source, the lifting electromagnet 43, and the external power supply are all electrically connected to the external power supply through an external control switch group. The external control switch group includes a general PLC controller. The distance sensor 217 is bidirectionally electrically connected to the PLC controller in the external control switch group. Each control switch group controls the operation of the corresponding electrical device using methods commonly used in the prior art. In addition, the mounting block 24 is easy to disassemble or move to allow for fine-tuning of the installation position according to the specific shape and height of the wheel.

[0033] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A sandblasting device for surface repair of flow components of a water turbine, characterized in that: It includes a ring seat (1), a penetration sandblasting unit (2), a torsional flat sweeping unit (3), and a workpiece lifting unit (4); Annular seat (1): Located at the bottom of the device; The sandblasting unit (2) includes a bottom ring (21), an upper ring (22), a flexible flexible connector (23), a mounting block (24), a sandblasting head (25), and a reserved connector (219). The bottom ring (21) is arranged parallel to the top of the annular seat (1), and the upper ring (22) is arranged parallel to the top of the bottom ring (21). The centers of the annular seat (1), the bottom ring (21), and the upper ring (22) are located on the same vertical axis. The diameter of the upper ring (22) is larger than the diameter of the bottom ring (21) but smaller than the diameter of the annular seat (1). The upper ring (22) and the bottom ring (21) are arranged parallel to the top of the bottom ring (21). The bottom ring (21) has a chamfered bevel at one end, and a pre-reserved connector (219) is arranged in a ring array on both chamfered bevels. Fifteen inclined flexible flexible tubes (23) are connected in a ring array between the upper ring (22) and the bottom ring (21). The two ends of the flexible flexible tubes (23) are respectively connected to the pre-reserved connectors (219) on the opposite side of the bottom ring (21) and the upper ring (22) through a screw connector. A U-shaped mounting block (24) is installed in the middle section of each flexible flexible tube (23). A sandblasting head (25) is installed on both sides of the mounting block (24). Torsional flat sweeping unit (3): installed inside the annular seat (1) and on the upper right side; Workpiece lifting unit (4): installed directly above the upper ring (22).

2. The sandblasting device for surface repair of turbine flow components according to claim 1, characterized in that: The probing sandblasting unit (2) also includes a vertical guide rod (26), a connecting block (27), a limiting block (28), and a spring (29). Four vertical guide rods (26) are fixedly connected to the upper end of the ring seat (1). Four connecting blocks (27) are fixedly connected to the outer circumference of the upper ring (22). The four connecting blocks (27) are arranged in a square diagonal distribution and are slidably connected to one vertical guide rod (26) respectively. Two limiting blocks (28) are fixedly connected to the upper position of the vertical guide rod (26). A spring (29) is provided between the two limiting blocks (28). The spring (29) is sleeved on the outer side of the vertical guide rod (26). The connecting block (27) presses on the upper end of the spring (29).

3. The sandblasting device for surface repair of turbine flow components according to claim 1, characterized in that: The workpiece lifting unit (4) includes a hydraulic cylinder (41), a lifting bracket (42), and a lifting electromagnet (43). The cylinder body of the hydraulic cylinder (41) is vertically arranged and connected to an external hydraulic source. The telescopic rod of the hydraulic cylinder (41) is vertically downward and coincides with the axis of the center of the three rings: the ring seat (1), the bottom ring (21), and the upper ring (22). A lifting electromagnet (43) is installed and fixed at the lower end of the telescopic rod. Four approximately Z-shaped lifting brackets (42) are arranged in a circular array on the outer side of the cylinder body of the hydraulic cylinder (41). The lower end of the lifting bracket (42) rests on the lower side of the cylinder body of the hydraulic cylinder (41). The upper end of the lifting bracket (42) is provided with bolt through holes and bolts are installed to fix it to the top of the wall or the external frame.

4. A sandblasting device for surface repair of turbine flow components according to claim 3, characterized in that: The workpiece lifting unit (4) also includes linkage rods (44). Four horizontal linkage rods (44) are provided on the outside of the telescopic rod of the hydraulic cylinder (41). The four linkage rods (44) are arranged in a cross shape, and a ring is fixedly connected to the inner end. The ring is sleeved on the outside of the telescopic rod of the hydraulic cylinder (41) and fixed by bolts.

5. A sandblasting device for surface repair of turbine flow components according to claim 1, characterized in that: The penetration sandblasting unit (2) also includes a locking block (210), fixing bolts (211), retaining rings (212) and elastic ribs (218). The U-shaped mounting block (24) is locked on the outside of the elastic flexible tube (23). A thin elastic rib (218) is fixedly connected to the inner side of the elastic flexible tube (23). The ends of the elastic rib (218) and the middle section are fixedly connected to circular retaining rings (212). The retaining rings (212) are locked on the outside of the elastic flexible tube (23). Square through holes are opened on both the left and right sides of the mounting block (24). The locking block (210) is a U-shaped structure, and its two ends are inserted into the square through holes on the side of the mounting block (24). Two fixing bolts (211) are threadedly connected to the open side of the mounting block (24). The threaded shaft of the fixing bolts (211) presses the locking block (210) against the elastic flexible tube (23).

6. A sandblasting device for surface repair of turbine flow components according to claim 1, characterized in that: The probing sandblasting unit (2) also includes a three-way connector (213), a solenoid valve (214) and a PLC controller (215). Four right-angled blocks are fixedly connected to the left and right sides of the mounting block (24). The right-angled blocks are fixed to the four corners of the sandblasting head (25). The sandblasting head (25) is rectangular and has a long strip-shaped nozzle on its outer side. The upper and lower ends of the nozzle are V-shaped and outwardly expanded. The internal channel near the corner of the device is rounded. A three-way connector (213) is connected to the outer end of the sandblasting head (25). A solenoid valve (214) is installed at each of the two inlet ends of the three-way connector (213). A small PLC controller (215) is installed at the corner of the mounting block (24). The two solenoid valves (214) are electrically connected to the external power supply through the PLC controller (215).

7. A sandblasting device for surface repair of turbine flow components according to claim 6, characterized in that: The penetration sandblasting unit (2) also includes a light sensor (216) and a distance sensor (217). The light sensor (216) is installed on the upper edge of the mounting block (24), and the distance sensor (217) is installed at the center of the square end face of the mounting block (24). The light sensor (216) and the distance sensor (217) are also connected to an external power supply through a PLC controller (215).

8. A sandblasting device for surface repair of turbine flow components according to claim 1, characterized in that: The torsional flat sweeping unit (3) includes a toothed belt (31), a servo motor (32) and a gear (33). A section of toothed belt (31) is fixedly connected to the arc segment area corresponding to a continuous 60° central angle on the right side of the outer circumference of the bottom ring (21). The servo motor (32) is installed and fixed on the upper right side of the ring seat (1). The upper end of the servo motor (32) is rotatably connected to the gear (33), and the gear (33) meshes with the toothed belt (31).

9. A sandblasting device for surface repair of turbine flow components according to claim 1, characterized in that: The torsional flat sweeping unit (3) also includes a bracket (34) and a tray (35). The bracket (34) is fixedly connected inside the annular seat (1). The bracket (34) consists of a bottom cross-shaped connecting rod and a central pillar. The tray (35) is fixedly connected to the upper end of the bracket (34). The edge of the tray (35) is a stepped structure. The upper end of the tray (35) is inserted into and rotatably connected to the inside of the bottom ring (21). The lower end of the tray (35) rests on the lower side of the bottom ring (21).

10. The method of using a sandblasting device for surface repair of turbine flow components according to any one of claims 1-9, wherein the specific steps of use are as follows: S1): First, tighten the screw joints at both ends of the flexible flexible tube (23) to the reserved joints (219) on the opposite side of the bottom ring (21) and the upper ring (22). Then, install the U-shaped mounting block (24) on the outside of the flexible flexible tube (23) with the opening facing outward, and tighten the fixing bolt (211) so that the locking block (210) and the mounting block (24) are locked together on the outside of the flexible flexible tube (23), thus completing the installation and fixing of the sandblasting head (25) in the middle section of the flexible flexible tube (23). S2): Then connect the two inlet ends of the three-way connector (213) to the external air source and the sand source respectively with soft material conveying pipes, and connect the two solenoid valves (214), the light sensor (216), and the distance sensor (217) to the PLC controller (215) on each side. Set the parameters at the PLC controller (215) so that when the light sensor (216) detects that the light is blocked by the workpiece to be repaired, the two solenoid valves (214) can be automatically opened by the PLC controller (215) to realize the connection of the external air source and the sand source. 11.S3): Start the lifting electromagnet (43) and fix the wheel workpiece to be repaired horizontally to the lower side of the lifting electromagnet (43). Then start the hydraulic cylinder (41) to make the lifting electromagnet (43) carry the wheel workpiece down to the elastic soft tube (23) of the ring array; the linkage pressure rod (44) will press on the upper ring (22), and then push the upper ring (22) to slide down along the vertical guide rod (26), which will squeeze the elastic soft tube (23) and make the elastic soft tube (23) squeeze. The flexible connector (23) arches inward, driving the sandblasting head (25) into the narrow gap of the rotor blades to perform sandblasting on the blade surface; the distance sensor (217) monitors the distance between the mounting block (24) and the center of the rotor workpiece in real time. When the mounting block (24) reaches the middle position of the blade gap and the rotor workpiece descends to a position where its middle line is slightly lower than the vertical height of the sandblasting head (25), the workpiece is stopped from moving downward and the sandblasting head (25) is stopped at the middle depth of the blade gap. S4): After the sandblasting head (25) enters the narrow gap of the rotor blade, the servo motor (32) is started to rotate back and forth at a certain angle, which drives the bottom ring (21) to rotate back and forth at the corresponding angle. The rotation of the bottom ring (21) will bring a twisting effect to the elastic soft tube (23), which in turn drives the sandblasting head (25) to rotate horizontally, thereby performing the action of sweeping sandblasting. The sandblasting heads (25) on both sides perform sandblasting repair on the surface of the adjacent blades. After the repair is completed, the hydraulic cylinder (41) drives the workpiece to move upward and reset. During this process, the elastic soft tube (23) returns to straight, and the mounting block (24) carries the sandblasting head (25) to automatically withdraw outward without affecting the upward movement of the rotor workpiece.

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