Main pump hydraulic component rotor lifting and shaft coiling device

Abstract

The invention discloses a maintenance device for a hydraulic component rotor of a main pump of a nuclear power station. The maintenance device comprises a rotor lifting mechanism, a guiding mechanism, an aligning mechanism and a disc shaft and rotating shaft positioning and locking mechanism. The rotor lifting mechanism adopts the combination of an electric hydraulic telescopic cylinder and a flange linear bearing, so that stable lifting with the precision of 0.05 mm is realized; the aligning mechanism ensures accurate centering of a stress center through multi-degree-of-freedom adjustment of a four-jaw chuck; the positioning and locking mechanism enhances the stability by combining a split-half shaft sleeve and a cone plate and matching with a high-strength bolt; the disc shaft mechanism is provided with a slewing bearing disc and a self-balancing lifting point to adapt to different installation states of the sealing chamber. Through modular foreign matter prevention design and nuclear power grade material application, the device solves the problems of aligning deviation, heavy structure and the like in traditional maintenance, has high precision, high reliability and wide working condition adaptability, and remarkably improves the maintenance efficiency and safety of the main pump.

Description

Technical Field

[0001] The present invention belongs to the technical field of the maintenance of main pumps in nuclear power plants, and particularly relates to a special device for simulating on-site shaft lifting, barring gear turning and inspecting the maintenance quality after the refurbishment of the hydraulic components of the main pump, and is particularly applicable to the lifting, centering, shaft turning and positioning and locking operations of the rotor of the hydraulic components of the main pump in nuclear power plants. Background Art

[0002] In the refurbishment process of the hydraulic components of the main pump in a nuclear power plant, it is necessary to repair and reassemble the disassembled parts. Since the sizes of the repaired parts are different from the original design, the hydraulic components after reassembly may not conform to the original design in terms of the axial and radial dimension chains, and it is necessary to verify the rotor flexibility and installation accuracy through shaft lifting, seating and barring gear turning operations.

[0003] Traditional operations rely on temporary on-site tools and have the following problems:

[0004] (1) Insufficient lifting accuracy: Manual operation is difficult to ensure the repeat positioning accuracy (usually > 0.1 mm), which easily leads to rotor offset or collision;

[0005] (2) Limited centering ability: The existing chuck structure cannot achieve precise adjustment in multiple degrees of freedom, and it is difficult to ensure the concentricity between the device and the rotor;

[0006] (3) Bulky structure: There are many temporarily assembled components, the operation space is limited, and there is a lack of foreign object prevention design, which easily introduces impurities;

[0007] (4) Poor applicability: It cannot be compatible with the two scenarios of installed and uninstalled seal chambers, and it is necessary to frequently adjust the tool configuration. Summary of the Invention

[0008] The technical solution adopted by the present invention to solve this technical problem is: a rotor lifting and shaft turning device for the main pump hydraulic components. The device includes a connecting plate, a rotor lifting mechanism, a lifting guiding mechanism, a rotor shaft turning mechanism, a rotor centering mechanism, and a shaft positioning and locking mechanism. Among them, the rotor lifting mechanism is composed of 3-4 sets of electro-hydraulic telescopic cylinders. Its upper part is connected to a four-jaw chuck by bolts, and its lower part is embedded in the square positioning groove of the connecting plate and fixed by bolts; the lifting guiding mechanism is composed of a support rod and a flanged linear bearing. The support rod includes smooth cylindrical rods A, B, D and flange C. The diameter of smooth cylindrical rod A is smaller than D, and D is smaller than B. Flange C is fixed to the connecting plate through countersunk bolt holes; the rotor centering mechanism adopts a four-jaw chuck structure, integrating a radial adjustment system, an axial adjustment system, and a clamping system, and realizes dynamic axis calibration with an accuracy of ±0.05 mm through adjustment bolts; the rotor shaft turning mechanism is a four-point contact ball type slewing bearing disc, with 4-6 circumferentially evenly distributed threaded holes on the outer ring, and the contact surface between the inner ring and the centering chuck jaws is treated with a high-hardness coating; the shaft positioning and locking mechanism is composed of a split half shaft sleeve, upper and lower tapered plates, and high-strength alloy steel tension bolts. The lower tapered plate is connected to the slewing bearing disc by bolts. The split half shaft sleeve clamps the shaft coupling, and the thread surface of the tension bolt is pre-coated with an anti-seize agent.

[0009] Further, the support rods of the lifting guiding mechanism and the electro-hydraulic telescopic cylinders are evenly and symmetrically distributed at intervals. The flanged linear bearing can be replaced with a linear guide rail or an air-floating guide rail. The countersunk bolt holes of flange C adopt a spring washer anti-loosening design. During the lifting process, the radial offset is eliminated through the guiding mechanism, and the repeat positioning accuracy reaches 0.05 mm.

[0010] Further, the four-jaw chuck of the rotor centering mechanism can be replaced with a three-jaw or six-jaw structure, and the driving mode supports manual, hydraulic or electric modes. The radial adjustment system compensates for the rotor center offset in real time to ensure the concentricity consistency of shaft lifting and shaft turning.

[0011] Further, the hoisting ring threaded holes on the outer ring of the slewing bearing disc of the rotor shaft turning mechanism are integrally designed with self-balancing hoisting points, and the load is evenly distributed during hoisting; the inner ring adopts SKF / FAG brand bearings, combined with a grease injection lubrication channel and a dust-proof sealing structure, to reduce friction loss and adapt to the two-way static load working condition.

[0012] Further, the lower tapered plate of the shaft positioning and locking mechanism is provided with 6 circumferentially evenly distributed threaded holes. The upper tapered plate and the split half shaft sleeve form a tapered surface lock through the tension bolt. The locking torque is adjustable, and disassembly and maintenance are convenient, avoiding thread biting damage.

[0013] Furthermore, the device adopts a modular design, and each mechanism is bolted through a standardized interface. Key components are made of S30408 stainless steel or 9Cr1Mo steel. A PEEK protective layer is added outside the slewing bearing disc. Combining the overall foreign object prevention structure and fillet transition process, it can meet the long-term stable operation under the nuclear power environment of 5 - 40°C / 95% humidity and radioactive conditions.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] (1) Through the coordinated layout of multiple groups of electro-hydraulic telescopic cylinders and guiding support rods, combined with the split half-shaft sleeve and conical surface locking structure, smooth lifting under a load of 3 tons can be achieved, with a repeat positioning accuracy of 0.05 mm, a safety factor of 1.5, and no shaking under the two-way static load condition;

[0016] (2) The dynamic center adjustment function of the centering chuck ensures that the concentricity deviation between the shaft lifting and the turning is ≤0.05 mm, avoiding rotor collision damage, and adapting to two scenarios: with / without the sealing chamber installed;

[0017] (3) The modular design and standardized interface reduce the on-site assembly workload, and the foreign object prevention structure and PEEK layer reduce the risk of foreign object intrusion in the radioactive environment;

[0018] (4) The integrated design of the self-balancing lifting point and the lightweight slewing bearing disc can achieve a lifting height of 114 mm, support single-person manual turning and anti-loosening locking, and improve the operation efficiency by 40%;

[0019] (5) The nuclear power grade materials are combined with SKF / FAG bearings for grease lubrication, with a service life of over 10 years, meeting the reliability requirements in the harsh environment of 40°C / 95% humidity. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is the overall structural schematic diagram of the rotor lifting and shaft turning device for the main pump hydraulic components of the present invention;

[0021] Figure 2 is the external shape schematic diagram of the rotor lifting and shaft turning device for the main pump hydraulic components of the present invention;

[0022] Figure 3 is the connection schematic diagram of the rotor lifting and shaft turning device for the main pump hydraulic components of the present invention;

[0023] In the figure: 1. Pump body; 2. Connection disc; 3. Support rod; 4. Flange type linear bearing; 5. Four-jaw chuck; 6. Slewing bearing disc; 7. Lifting ring; 8. Upper conical plate; 9. Coupling; 10. Split half-shaft sleeve; 11. Lower conical plate; 12. Electro-hydraulic telescopic cylinder.

[0024] Figure 4 is the structural schematic diagram of the connection disc of the present invention;

[0025] Figure 5 Schematic structural diagram of the lifting guiding mechanism of the present invention;

[0026] Figure 6 Schematic structural diagram of the rotor centering mechanism of the present invention;

[0027] Figure 7 Schematic structural diagram of the shaft positioning and locking mechanism of the present invention;

[0028] Figure 8 Schematic structural diagram of the rotor disc shaft mechanism of the present invention. Detailed implementation manners

[0029] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the embodiments described herein are only used to explain the present invention, rather than limiting its protection scope.

[0030] As Figures 1 to 3 shown, the device includes a rotor lifting mechanism, a lifting guiding mechanism, a rotor centering mechanism, a rotor disc shaft mechanism, and a shaft positioning and locking mechanism.

[0031] As Figure 4 shown, the connecting disc is connected to the main pump sealing chamber or the fixed base through bolts, and its positioning hole (401) cooperates with the smooth cylindrical rod D of the support rod. The flange is fixed to the connecting disc through bolts; its square positioning groove (402) cooperates with the lower part of the electro-hydraulic telescopic cylinder of the rotor lifting mechanism and is fixed to the connecting disc through bolts.

[0032] As Figure 5 shown, the lifting guiding mechanism includes a support rod and a flanged linear bearing. The support rod is composed of smooth cylindrical rods A (501), B (502), D (504) and flange C (503). The countersunk bolt holes of flange C (503) adopt a loosening prevention structure. The flanged linear bearing (505) forms a sliding pair with the smooth cylindrical rod A (501) to ensure no jamming during the lifting process and high radial stability. The flanged linear bearing and the support rod are respectively fixed to the lower part of the adjustment chuck and the upper part of the connecting disc through bolts passing through the countersunk bolt holes (506) of the flange.

[0033] As Figure 6 shown, the rotor centering mechanism adopts a four-jaw chuck structure, including a radial adjustment system (adjustment bolt), an axial adjustment system (screw rod), and a clamping system (claw), supporting precise adjustment in multiple degrees of freedom to achieve precise centering of the rotor, ensuring that the force center of the device coincides with the center of the hydraulic components. The centering mechanism supports manual, hydraulic or electric drive and adapts to the requirements of the nuclear power environment.

[0034] As Figure 7As shown, the shaft positioning and locking mechanism includes a split half shaft sleeve, an upper conical plate, a lower conical plate, and a tensioning hexagon socket head bolt. The split half shaft sleeve is clamped on the shaft coupling. The upper and lower conical plates are provided with tensioning bolt holes (702) and are fixed by tensioning hexagon socket head bolts. The lower conical plate is provided with 4 to 6 countersunk threaded holes (701) evenly distributed in the circumferential direction, and the lower conical plate is fixed to the upper part of the slewing bearing disc by bolts.

[0035] As Figure 8 shown, the rotor disc shaft mechanism adopts a four-point contact ball type slewing bearing disc, which includes an inner ring (801), an outer ring (802), and rolling elements (803). The outer ring is evenly distributed with 3 to 4 lifting ring threaded holes in the circumferential direction for hoisting and fixing. The upper part of the inner ring of the slewing bearing disc is connected to the lower conical plate by bolts, and can bear bidirectional static loads (safety factor 1.5) to ensure no shaking during turning the shaft by hand.

[0036] The whole device adopts a foreign object prevention design. PEEK material protection layers are set at key connection parts to avoid friction damage with the sealing chamber. Self-balancing lifting points are provided at the top for convenient hoisting and transportation. The main materials are selected as S30408 stainless steel and 9Cr1Mo steel, and the bearing brands are preferably SKF, FAG or NSK.

[0037] As Figure 3 shown, this device is applicable to two scenarios: with and without the sealing chamber installed. In the working state, the electric hydraulic telescopic cylinder drives the rotor to be lifted to the set height (maximum 114 mm), and the digital scale displays the height in real time, with a repeat positioning accuracy of 0.05 mm. After the four-jaw chuck ensures concentricity, manual turning of the shaft is realized through the slewing bearing disc, with no shaking and anti-loosening throughout the process. The lightweight structure takes into account both strength and anti-collision requirements, meeting the high efficiency and safety of the main pump rotor maintenance and inspection in the nuclear power environment.

Claims

1. A rotor lifting and shaft turning device for the hydraulic components of a main pump, characterized in that The device includes a connecting plate, a rotor lifting mechanism, a lifting guiding mechanism, a rotor disc shaft mechanism, a rotor centering mechanism, and a rotating shaft positioning and locking mechanism; the rotor lifting mechanism is an electro-hydraulic telescopic cylinder composed of a motor, a hydraulic system, a control system, a sealing system, and a buffer system; the lifting guiding mechanism consists of a support rod and a flange linear bearing; the rotor centering mechanism is an adjusting chuck composed of a radial adjustment system, an axial adjustment system, a clamping system, and adjustment bolts; the rotor disc shaft mechanism is a slewing bearing disc composed of an inner ring, an outer ring, and rolling elements; the rotating shaft positioning and locking mechanism consists of a lower cone plate, a split half shaft sleeve, an upper cone plate, and tensioning socket head cap screws.

2. A rotor lifting and shaft turning device for the main pump hydraulic components according to claim 1, characterized in that: The upper part of the electro-hydraulic telescopic cylinder in the rotor lifting mechanism is connected to the lower part of the adjusting chuck by bolts, and its lower part is placed in the square positioning groove of the connecting plate and connected to the connecting plate by bolts.

3. A rotor lifting and shaft turning device for the main pump hydraulic components according to claim 1, characterized in that: The support rod of the lifting guiding mechanism consists of a smooth cylindrical rod A, a smooth cylindrical rod B, a flange C, and a smooth cylindrical rod D. The diameter of the smooth cylindrical rod A is smaller than that of the smooth cylindrical rod D, and the diameter of the smooth cylindrical rod D is smaller than that of the smooth cylindrical rod B. The flange linear bearing is fitted with the smooth cylindrical rod A and can move up and down along the smooth cylindrical rod A. Multiple countersunk bolt holes are provided at the four corners of the plane on one side of the smooth cylindrical rod B for the flange C.

4. A rotor lifting and shaft turning device for a main pump hydraulic component according to claim 1, characterized in that: The upper part of the flange linear bearing of the lifting guiding mechanism is connected to the lower part of the four-jaw chuck by bolts, the lower smooth cylindrical rod D is placed in the positioning hole of the connecting plate, and the flange C is connected to the connecting plate by bolts.

5. A rotor lifting and shaft turning device for a main pump hydraulic component according to claim 1, characterized in that: The rotor lifting mechanism assembly consists of 3-4 electro-hydraulic telescopic cylinders, and the lifting guiding mechanism assembly consists of 3-4 support rods and flange linear bearings. The electro-hydraulic telescopic cylinders and the support rods are arranged at equal intervals.

6. A rotor lifting and shaft disk mounting device for a main pump hydraulic component according to claim 1, characterized in that: The lower part of the four-jaw chuck is connected to the flange linear bearing and the electro-hydraulic telescopic cylinder by bolts. The upper part of the four-jaw chuck receives a four-point contact ball type slewing bearing, which is fixed at the center of the four-jaw chuck by the jaws, and its upper part is connected to the lower cone plate by bolts.

7. A rotor lifting and shaft disc mounting device for the main pump hydraulic component according to claim 1, characterized in that: The flange linear bearing of the lifting guiding mechanism can be replaced by a linear guide rail, a ball bushing, or an air-floating guide rail; the electro-hydraulic telescopic cylinder of the rotor lifting mechanism can be replaced by a linear motor, a pulley group traction type telescopic mechanism, or a rack and pinion lifting mechanism; the adjusting chuck of the rotor centering mechanism is a three-jaw or four-jaw or six-jaw chuck, and the driving method can be replaced by hydraulic or electric; the four-point contact ball type slewing bearing of the rotor disc shaft mechanism can be replaced by a roller slewing bearing, a cylindrical roller slewing bearing, or a combined slewing bearing.

8. A rotor lifting and shaft turning device for the main pump hydraulic components according to claim 1, characterized in that: The rotor lifting mechanism, the lifting guiding mechanism, the rotor centering mechanism, and the rotor disc shaft mechanism can be connected as a whole by bolts.

9. A rotor lifting and shaft turning device for a main pump hydraulic component according to claim 1, characterized in that: The lower cone plate of the rotating shaft locking and positioning mechanism is connected to the slewing bearing disc by bolts. The split half shaft sleeve is stuck on the rotating shaft coupling. The upper cone plate is placed above the split half shaft sleeve. The upper and lower cone plates are connected by tensioning socket head cap screws. The tensioning socket head cap screw rod passes through the upper cone plate and is threaded into the screw hole of the lower cone plate. There are 4-6 circumferentially evenly distributed screw holes on the lower cone plate.

10. A rotor lifting and shaft turning device for the main pump hydraulic component according to claim 1, characterized in that: The upper surface of the slewing bearing disc of the disc shaft mechanism has 4-6 threaded holes evenly distributed in a circumference, and the slewing bearing disc is connected to the lower conical plate by bolts; the slewing bearing disc is placed inside the rotor centering mechanism, and the jaws of the adjustment chuck of the rotor centering mechanism grip the outer circumferential surface of the slewing bearing disc.

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