A method for overhauling a guide vane bearing sleeve mechanism of a large hydroelectric generator set

Abstract

The application discloses a kind of large-scale water turbine generator set guide vane bearing sleeve mechanism overhauling method, comprising the following steps: lift the outer top cover on guide vane to preset height;After every interval preset number of guide vane, support bracket is set on target guide vane as support guide vane, for supporting the outer top cover;Remaining guide vane as to be overhauled guide vane;The bearing sleeve of the to-be-overhauled guide vane is replaced by the gap after the outer top cover is jacked up, and the overhauled guide vane is obtained;The support bracket is moved to the overhauled guide vane, and the bearing sleeve of the support guide vane is replaced, until all the guide vanes are replaced by the overhauled guide vane. The support bracket on the support guide vane plays a supporting role for the falling top cover, and the bearing sleeve of the to-be-overhauled guide vane is overhauled;Then the support bracket is replaced to the overhauled guide vane to overhaul the support guide vane, and the overhaul of all guide vanes is completed;Meanwhile, the method can complete the replacement of guide vane bearing sleeve in the machine pit, without lifting out the guide vane, improving the overhaul efficiency.

Description

Technical Field

[0001] This invention relates to the field of hydro-generator unit maintenance technology, and in particular to a method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit. Background Technology

[0002] Traditionally, overhauling the 24 guide vane bearing sleeve mechanisms requires lifting the 105.32-ton outer top cover in four sections multiple times within the pit to the installation site, then lifting the 24 guide vanes to a dedicated maintenance area for individual bearing sleeve mechanism overhaul. This approach has the following drawbacks: 1. The outer diameter of the outer top cover in large hydropower plants is larger than the maximum inner diameter of the pit, making it impossible to remove the entire cover from the pit. Furthermore, when lifting the outer top cover in sections, the space for disassembling the bolts is limited, making it difficult for workers to perform the task, and any deviation during reassembly poses a risk of technical non-compliance. 2. After being divided, the center of gravity of the outer top cover is not at its centroid, resulting in instability after lifting and an angle, increasing the risk of lifting, requiring multiple lifts, and increasing overall operational safety. 3. The existing process is complex, requiring disassembly and lifting of the outer top cover, lifting of the guide vanes, overhaul, lifting in, and reassembly of the outer top cover, consuming significant manpower and resources, increasing maintenance intensity, extending the construction period, and reducing the unit's power generation efficiency. Summary of the Invention

[0003] The technical problem to be solved by the present invention is: a method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator set, which improves the overhaul efficiency of the guide vane bearing sleeve mechanism of a large hydro-generator set and reduces safety risks.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0005] A method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit includes the following steps:

[0006] Raise the outer top cover on the guide vane to the preset height;

[0007] After each preset number of guide vanes, a bracket is set on the target guide vane as a supporting guide vane to support the outer top cover; the remaining guide vanes are used as guide vanes to be inspected.

[0008] The guide vane to be repaired is obtained by replacing the bearing sleeve of the guide vane to be repaired through the gap after the outer top cover is lifted.

[0009] Move the bracket onto the maintenance guide vane and replace the bearing sleeve supporting the guide vane until all the guide vanes have been replaced with the maintenance guide vanes.

[0010] The beneficial effects of this invention are as follows: After the outer top cover is lifted, all guide vanes are divided into supporting guide vanes and guide vanes to be inspected, and brackets are set on the supporting guide vanes. This allows the brackets to support the falling top cover, improving operational safety. Since the guide vanes to be inspected do not provide support, the bearing sleeves of the guide vanes to be inspected can be inspected. After all the guide vanes to be inspected have been inspected, the brackets are then replaced on the guide vanes to be inspected. That is, the guide vanes to be inspected provide support, while the supporting guide vanes do not, thus allowing the supporting guide vanes to be inspected. This completes the inspection of all guide vanes. At the same time, this method allows the replacement of the guide vane bearing sleeves to be completed within the machine pit, without having to lift the guide vanes out, improving inspection efficiency. Attached Figure Description

[0011] Figure 1 This is a flowchart illustrating the steps of a method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit according to an embodiment of the present invention.

[0012] Figure 2 This is a schematic diagram of a method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit according to an embodiment of the present invention;

[0013] Figure 3 This is a top view of a portion of the structure in a maintenance method for a guide vane bearing sleeve mechanism of a large hydro-generator set according to an embodiment of the present invention;

[0014] Figure 4 for Figure 3 A schematic diagram of the structure marked AA and BB;

[0015] Label Explanation:

[0016] 1. Outer top cover; 2. Guide vane; 3. Support frame; 4. Steel wire rope. Detailed Implementation

[0017] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0018] Please refer to Figure 1 A method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit, comprising the following steps:

[0019] A method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit includes the following steps:

[0020] Raise the outer top cover on the guide vane to the preset height;

[0021] After each preset number of guide vanes, a bracket is set on the target guide vane as a supporting guide vane to support the outer top cover; the remaining guide vanes are used as guide vanes to be inspected.

[0022] The guide vane to be repaired is obtained by replacing the bearing sleeve of the guide vane to be repaired through the gap after the outer top cover is lifted.

[0023] Move the bracket onto the maintenance guide vane and replace the bearing sleeve supporting the guide vane until all the guide vanes have been replaced with the maintenance guide vanes.

[0024] As described above, the beneficial effects of this invention are as follows: After the outer top cover is lifted, all guide vanes are divided into supporting guide vanes and guide vanes to be inspected, and brackets are set on the supporting guide vanes, thereby supporting the falling top cover and improving operational safety. Since the guide vanes to be inspected do not provide support, the bearing sleeves of the guide vanes to be inspected can be inspected. After all the guide vanes to be inspected have been inspected, the brackets are then replaced on the guide vanes to be inspected, meaning the guide vanes to be inspected provide support while the supporting guide vanes do not, thus allowing the supporting guide vanes to be inspected. This completes the inspection of all guide vanes. Furthermore, this method allows for the replacement of guide vane bearing sleeves within the machine pit, eliminating the need to lift the guide vanes out, thus improving inspection efficiency.

[0025] Furthermore, raising the outer top cover on the guide vane to a preset height includes:

[0026] Remove the flange from the outer top cover;

[0027] The outer top cover is lifted to a first height using the set screw, and the spacing between the outer top cover and all the guide vanes is checked to ensure that they are the same.

[0028] If so, the outer top cover is lifted to the preset height using a bridge crane.

[0029] As described above, by first lifting the outer top cover to the first height and confirming that there is a distance of the first height between the outer top cover and all guide vanes, the outer top cover is then lifted to the preset height, thus avoiding the danger of forcibly lifting the outer top cover before it is completely separated from the seat ring.

[0030] Furthermore, the first height is 1-2mm; the preset height is 900-950mm.

[0031] As described above, setting the first height to 1-2mm makes it easy for operators to identify whether the outer top cover and the seat ring are separated, and the lifting height is small, which is less likely to cause danger; while setting the preset height to 900-950mm ensures that the subsequent guide vanes have enough space to be lifted for the maintenance of the bearing sleeve.

[0032] Furthermore, the step of setting a support bracket on the target guide vane as a support for the guide vane includes:

[0033] A wedge plate is provided between the bracket and the outer top cover to compensate for the gap between the bracket and the outer top cover.

[0034] As described above, by using wedge plates to compensate for the gap between the support and the outer top cover, the force on the outer top cover is ensured to be uniform, thereby improving operational safety.

[0035] Furthermore, replacing the bearing sleeve of the guide vane to be inspected by lifting the gap after the outer top cover is completed includes:

[0036] The guide vanes to be inspected are pulled up one by one using a first chain hoist and then fixed in place.

[0037] The bearing sleeve of the guide vane to be inspected is inspected;

[0038] Lower the guide vanes that have been repaired until all the guide vanes have been repaired.

[0039] As can be seen from the above description, fixing the guide vane to be inspected can prevent the guide vane from falling suddenly and avoid safety hazards during the operation.

[0040] Furthermore, the maintenance of the bearing sleeve of the guide vane to be inspected includes:

[0041] The guide vane bushing joint of the guide vane to be inspected is pried open with a special screwdriver, causing the bearing bushing to deform.

[0042] Remove the misaligned bearing sleeve;

[0043] Insert the new bearing into a special bearing assembly tool, control the first hand chain hoist to slowly lower the guide vane to be inspected, and press the new bearing evenly into the shaft hole;

[0044] Apply lubricant evenly to the surface of the new bearing sleeve and replace the sealing ring;

[0045] The guide vane to be inspected is reinstalled in its original position.

[0046] As described above, by using a special screwdriver to deform the bearing sleeve, the bearing sleeve can be removed from its misalignment. Furthermore, by applying lubricant evenly to the surface of the new bearing sleeve and replacing the sealing ring, the working effect of the new bearing sleeve and guide vane is improved.

[0047] Furthermore, the step of reinstalling the guide vane to be inspected in its original position includes:

[0048] The upper and lower surfaces of the guide vane to be inspected are ground smooth.

[0049] The polished guide vane to be inspected is then reinstalled in its original position.

[0050] As can be seen from the above description, grinding the upper and lower surfaces of the guide vane to be inspected improves the engagement effect between the guide vane and the bearing sleeve.

[0051] Furthermore, the step of setting a support bracket on the target guide vane as a support for the guide vane includes:

[0052] A second hand chain hoist is installed on the side of the outer top cover away from the guide vane, and the outer top cover is hung by the second hand chain hoist.

[0053] As described above, using a second hand-operated hoist as a force-bearing aid to hold the outer top cover in place prevents it from tipping over and improves safety during operation.

[0054] Furthermore, the support frame includes a support rod and a jack;

[0055] The support rod is connected to the head and tail of the jack and is located between the outer top cover and the guide vane.

[0056] As described above, the jacks can provide sufficient support for the outer top cover, and the support rods and jacks ensure that there is enough space between the outer top cover and the guide vane for maintenance of the guide vane to be inspected.

[0057] Furthermore, the step of setting a support bracket on the target guide vane as a support for the guide vane after each predetermined number of guide vanes includes:

[0058] Half of the guide vanes, symmetrically distributed, are selected as the supporting guide vanes.

[0059] As can be seen from the above description, using half of the guide vanes as supporting guide vanes, and symmetrically distributing the supporting guide vanes, makes the outer top cover more uniformly stressed.

[0060] The maintenance method for the guide vane bearing sleeve mechanism of a large hydro-generator unit provided by this invention can be applied to the maintenance and replacement of guide vane bearing sleeves in large hydro-generator units. The specific implementation method is described below:

[0061] Please refer to the figure; Embodiment 1 of the present invention is as follows:

[0062] Example 1

[0063] Please refer to Figure 1 and Figure 2 A method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit, comprising the following steps:

[0064] S1. Raise the outer top cover 1 on the guide vane 2 to the preset height, specifically:

[0065] S11. Remove the flange on the outer top cover 1;

[0066] S12. Lift the outer top cover 1 to the first height using the set screw bolts, and check whether the distance between the outer top cover 1 and all the guide vanes 2 is the same; if so, lift the outer top cover 1 to the preset height using the bridge crane; for example, in a specific embodiment: first, slowly lift the outer top cover 1 by 1-2mm using 10-M64 set screw bolts, and check that there should be a gap around the whole circle; then arrange special lifting tools and suspend steel wire ropes 4 according to the actual site conditions; finally, slowly lift the outer top cover 1 by 900-950mm using the bridge crane.

[0067] S2. After each preset number of guide vanes 2, a bracket 3 is set on the target guide vane 2 as a supporting guide vane to support the outer top cover 1; the remaining guide vanes 2 are used as guide vanes to be inspected; for example, half of the guide vanes 2 are selected and symmetrically distributed as the supporting guide vanes; or in an actual arrangement, 6 weight conversion supports are evenly distributed on the outer top cover 1, with two guide vanes 2 corresponding to each support, that is, a total of 12 supporting guide vanes; in order to ensure that the outer top cover 1 is subjected to uniform force, the operator can directly select the guide vanes 2 corresponding to the 6 supports as supporting guide vanes, and the arrangement method is more intuitive and convenient.

[0068] In an optional embodiment, the bracket 3 is symmetrically arranged relative to the guide vane 2, that is, one guide vane 2 is provided with two sets of brackets 3; the support height of the bracket 3 is 870mm; the bracket 3 includes a support rod and a jack; the support rod and the jack are connected end to end and are disposed between the outer top cover 1 and the guide vane 2; the support rod and the jack are fixedly connected by ropes or other tools to prevent them from falling off and causing injury;

[0069] In a further embodiment, to enhance the supporting effect between the bracket 3 and the outer top cover 1, a wedge plate is also provided between the bracket 3 and the outer top cover 1 to compensate for the gap between the bracket 3 and the outer top cover 1; the wedge plate ensures that all supporting surfaces are on the same horizontal plane, guaranteeing that the outer top cover 1 is subjected to uniform force; that is, the supporting components consist of three parts: the support rod, the jack, and the wedge plate; in the working state, the support rod is placed on the upper end face of the guide vane 2, the jack is placed on the upper part of the support rod, and the upper part of the jack is driven into the wedge plate as needed to support the plane of the outer top cover 1; then the bridge crane is controlled to slowly descend, supporting the outer top cover 1 on the 24 support points of the 12 guide vanes 2.

[0070] S3. Replace the bearing sleeve of the guide vane to be inspected by prying up the gap after lifting the outer top cover 1 to obtain the guide vane to be inspected, including:

[0071] S31. The guide vanes to be inspected are pulled up one by one by the first hand chain hoist and the guide vanes to be inspected are fixed; if a special lifting lug is used on the foundation, the guide vane 2 is lifted by the hand chain hoist, and the lifting height is controlled at 800-850mm; at the same time, the large and small heads of the guide vane 2 are fixed with a special support to prevent the guide vane 2 from falling suddenly.

[0072] S32. Inspect the bearing sleeve of the guide vane to be inspected, specifically:

[0073] S321. Using a special screwdriver, pry open the guide vane bushing joint of the guide vane to be inspected, deform the bearing sleeve, and then remove the bearing sleeve out of misalignment.

[0074] S322. Insert the new bearing into a special bearing assembly tool, control the first hand chain hoist to slowly lower the guide vane to be inspected, and press the new bearing evenly into the shaft hole;

[0075] S323. Apply lubricant evenly to the surface of the new bearing sleeve and replace the sealing ring;

[0076] S325. Grind the upper and lower surfaces of the guide vane to be inspected until smooth.

[0077] S326. Reinstall the polished guide vane to be inspected back in its original position;

[0078] S33. Lower the guide vanes that have been repaired and are to be repaired until all the guide vanes to be repaired have been repaired.

[0079] In an optional embodiment, before maintenance, a second hand chain hoist can be installed on the side of the outer top cover 1 away from the guide vane 2, and the outer top cover 1 can be hung by the second hand chain hoist; for example, in a specific embodiment, the outer top cover 1 can be hung by four 10-ton hand chain hoists in a symmetrical direction as force assistance to prevent the outer top cover 1 from tipping over.

[0080] Lifting points are provided directly above each of the 24 guide vanes 2 in the pit, for lifting the guide vanes 2 during maintenance to facilitate the inspection of the bearing sleeves of the guide vanes 2; both the first and second hand chain hoists are set through the lifting points; the second hand chain hoist selects 4 symmetrical lifting points from the 24 lifting points, and the second hand chain hoist is slightly lifted vertically upward to hang the outer top cover 1; under normal circumstances, the second hand chain hoist will not apply a pulling force to the outer top cover 1, but if the outer top cover 1 becomes unbalanced due to some factor and tends to tilt to one side, the second hand chain hoist on the opposite side will immediately generate a pulling force to ensure the balance of the outer top cover 1.

[0081] S4. Move the bracket 3 onto the maintenance guide vane and replace the bearing sleeve supporting the guide vane until all the guide vanes 2 are replaced with the maintenance guide vanes; for example, all the brackets 3 can be set on the next guide vane 2 in a clockwise or counterclockwise direction.

[0082] S5. Lower the outer top cover 1 and reinstall the flange onto the outer top cover 1.

[0083] In summary, the present invention provides a method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit. After the outer top cover is lifted, all guide vanes are divided into supporting guide vanes and guide vanes to be inspected. A bracket is installed on the supporting guide vane, which supports the falling top cover, improving operational safety. Since the guide vane to be inspected does not provide support, its bearing sleeve can be inspected. After all guide vanes to be inspected have been inspected, the bracket is replaced on the guide vane to be inspected, where the guide vane to be inspected provides support while the supporting guide vane does not, thus allowing for inspection of the supporting guide vane. This completes the inspection of all guide vanes. Furthermore, this method allows for the replacement of guide vane bearing sleeves within the turbine pit, eliminating the need to lift the guide vanes out, thus improving maintenance efficiency.

[0084] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit, characterized in that, Including the following steps: Raise the outer top cover on the guide vane to the preset height; After each preset number of guide vanes, a bracket is set on the target guide vane as a supporting guide vane to support the outer top cover; the remaining guide vanes are used as guide vanes to be inspected. The guide vane to be repaired is obtained by replacing the bearing sleeve of the guide vane to be repaired through the gap after the outer top cover is lifted. Move the bracket onto the maintenance guide vane and replace the bearing sleeve supporting the guide vane until all the guide vanes are replaced with the maintenance guide vanes; The process of replacing the bearing sleeve of the guide vane to be inspected by opening up the gap after lifting the outer top cover includes: The guide vanes to be inspected are pulled up one by one using a first chain hoist and then fixed in place. The bearing sleeve of the guide vane to be inspected is inspected; Lower the guide vanes that have been repaired and are to be repaired, until all the guide vanes to be repaired have been repaired; The maintenance of the bearing sleeve of the guide vane to be inspected includes: The guide vane bushing joint of the guide vane to be inspected is pried open with a special screwdriver, causing the bearing bushing to deform. Remove the misaligned bearing sleeve; Insert the new bearing into a special bearing assembly tool, control the first hand chain hoist to slowly lower the guide vane to be inspected, and press the new bearing evenly into the shaft hole; Apply lubricant evenly to the surface of the new bearing sleeve and replace the sealing ring; Reinstall the guide vane to be inspected in its original position; The step of reinstalling the guide vane to be inspected back in its original position includes: The upper and lower surfaces of the guide vane to be inspected are ground smooth. The polished guide vane to be inspected is then reinstalled in its original position.

2. The method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit according to claim 1, characterized in that, The step of raising the outer top cover on the guide vane to a preset height includes: Remove the flange on the outer top cover; The outer top cover is lifted to a first height using the set screw, and the spacing between the outer top cover and all the guide vanes is checked to ensure that they are the same. If so, the outer top cover is lifted to the preset height using a bridge crane.

3. The method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit according to claim 2, characterized in that, The first height is 1-2mm; the preset height is 900-950mm.

4. The method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit according to claim 1, characterized in that, The step of setting a support bracket on the target guide vane to support the guide vane includes: A wedge plate is provided between the bracket and the outer top cover to compensate for the gap between the bracket and the outer top cover.

5. A method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit according to claim 1, characterized in that, The step of setting a support bracket on the target guide vane to support the guide vane includes: A second hand chain hoist is installed on the side of the outer top cover away from the guide vane, and the outer top cover is hung by the second hand chain hoist.

6. A method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit according to claim 1, characterized in that, The support frame includes a support rod and a jack; The support rod is connected to the head and tail of the jack and is located between the outer top cover and the guide vane.

7. A method for overhauling the guide vane bearing sleeve mechanism of a large hydro-generator unit according to claim 1, characterized in that, The provision of a support bracket on the target guide vane after each preset number of guide vanes includes: Half of the guide vanes, symmetrically distributed, are selected as the supporting guide vanes.

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