A method and device for adjusting the center and level of a large-scale Francis turbine runner

Abstract

A method and device for adjusting the center and level of a large Francis turbine runner uses a coincident level to measure and calculate the thickness of each wedge plate pad at four symmetrical locations on the runner or main shaft flange surface. Copper pads are then added to ensure the runner's levelness meets the required level. Center adjustment devices are installed at these four locations, and the runner center is adjusted to meet the required level by measuring and calculating the target value and adjustment amount. This method and device for adjusting the center and level of a large Francis turbine runner can reduce the number of runner adjustments.

Description

Technical Field

[0001] The present invention relates to large and medium-sized Francis turbine generator sets, and in particular to a method and device for adjusting the center and level of a runner of a large Francis turbine generator set. The method is suitable for adjusting the center and level of a runner when the runner is reinstalled after an overhaul of the large and medium-sized Francis turbine generator set. The method can minimize the lifting and lowering of the runner to adjust the center and level of the runner to the correct position, avoid repeated lifting and lowering of the runner, improve work efficiency, and save human resources. Background Art

[0002] After the overhaul of a mixed-flow turbine generator set, when the runner is reinstalled, the runner needs to be adjusted horizontally to ≤0.02mm / m and the center to ≤0.15mm. The traditional method is to use a copper wedge plate to limit the runner and the bottom ring after the runner level is basically adjusted to meet the requirements, and adjust the runner center. This method requires continuous adjustment of the insertion depth of the wedge plate in at least 8 directions as the runner falls. Often, due to the lack of coordination between the personnel inserting the wedge plate, after the runner is completely dropped, the gap between the runner and the lower leak-proof ring in all directions is uneven, resulting in an unqualified runner center and the need to re-raise and lower the runner, which restricts the maintenance period of the unit. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method and device for adjusting the center and level of the runner of a large-scale mixed flow unit. When the runner is reinstalled after overhaul of the unit, the center and level of the runner can be adjusted quickly, reducing the number and amount of adjustments.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] A method for adjusting the center and level of a runner of a large Francis turbine unit comprises the following steps:

[0006] Step 1), measurement before repair;

[0007] Step 2) Initial level adjustment;

[0008] Step 3) Initial center adjustment;

[0009] Step 4) Level and center measurement and fine-tuning.

[0010] The step 1) includes the following steps:

[0011] Step 1.1) When turning the car before repair, measure the gap between the lower fixed leak-proof ring and the lower rotating leak-proof ring, and record them as a1, b1, c1, and d1;

[0012] Step 1.2) Before repair, after the force conversion is completed, the weight of the runner and the main shaft all falls on the wedge plates corresponding to the base ring. Spot weld the adjacent wedge plates and spot weld the wedge plates to the base ring firmly.

[0013] Step 1.3) Before repair, after the top cover and main shaft are lifted out and before the runner is lifted out, use a coincident level to measure the runner's level before repair in four symmetrical directions on the runner flange surface, avoiding the position of the runner lifting device. The level is recorded as θ and the azimuth angle is recorded as α.

[0014] The step 2) includes the following steps:

[0015] Step 2.1) Calculate the padding thickness of each wedge plate based on the level of the runner before repair in step 1.3) and add copper padding to the wedge plate;

[0016] Step 2.2), the distribution angles of wedge plates #1 to #8 are denoted as β(n);

[0017] Step 2.3), the theoretical adjustment height of each wedge plate is δ(n)=-D / 2*θ*cos(α-90°), where D is the distribution diameter of the wedge plate, and a positive calculated value indicates an upward adjustment;

[0018] Step 2.4), the final padding thickness of each wedge plate is Δ=δ(n)+|Min{δ(n), n=1~8}|;

[0019] Step 2.5) Add copper padding to the wedge plate according to the thickness of step 2.4). It is best if the copper padding covers the entire wedge plate.

[0020] The step 3) includes the following steps:

[0021] Step 3.1) Each unit uses 4 sets of center adjustment devices, and the 4 sets of center adjustment devices are evenly distributed around the circumference;

[0022] Step 3.2) Weld the stopper of the center adjustment device to the base ring near the measuring hole of the lower rotating leak-proof ring;

[0023] Step 3.3) Before the runner is hoisted into the pit, after adding copper padding as per step 2.5), apply grease or vaseline between the copper padding and the runner;

[0024] Step 3.4) Hoist the runner into the pit and lower it until the lower rotating leak-proof ring is 5-10mm away from the wedge plate. Adjust the center adjustment screws of the center adjustment devices so that the end support devices of each center adjustment device just touch the runner. Fix the runner 1 and measure the gaps between the lower fixed leak-proof ring and the lower rotating leak-proof ring, recording them as a2, b2, c2, and d2. At this time, the target gap of the runner in the x direction is x=(d2+b2) / 2, and the target gap in the y direction is y=(c2+a2) / 2;

[0025] Step 3.5) Adjust each center adjustment device to push the center of the wheel to the target center, and keep the bilateral gap between the end of each center adjustment device and the wheel at about 0.10mm;

[0026] Step 3.6) Continue to lower the wheel until all its weight falls onto the wedge plate.

[0027] In step 3.5), the adjustment amounts of the center adjustment screws of each center adjustment device are recorded as e, f, g, and h respectively:

[0028] The adjustment amount of the top screw in the +y direction is e=a2-y=(a2-c2) / 2-0.05;

[0029] The adjustment amount of the top screw in the +x direction is f=b2-x=(b2-d2) / 2-0.05;

[0030] -The adjustment amount of the top screw in the y direction is g=c2-y=(c2-a2) / 2-0.05;

[0031] -The adjustment amount of the top screw in the x direction is h=d2-y=(d2-b2) / 2-0.05.

[0032] The step 4) includes the following steps:

[0033] Step 4.1) Measure and calculate the level of the runner according to step 1.3); Measure and calculate the center of the runner according to step 3.4);

[0034] Step 4.2) If the runner is not level, calculate the amount of padding to be added to the wedge plates in each direction according to steps 2.2) to 2.5), lift the runner 1 to 3 mm, and add copper sheets of the corresponding thickness to the wedge plates; and control the runner center according to steps 3.1) to 3.5).

[0035] Step 4.3) If the runner center is unqualified, use the bridge crane to apply an upward force F to the runner so that the runner has a certain residual weight pressing on the wedge plate;

[0036] Step 4.4) Adjust the runner center again: tighten the center adjustment screws on each center adjustment device to the shortest possible length; install a single-acting, thin-type hydraulic jack between the end support device and the runner; if the single-acting, thin-type hydraulic jack is too thick to fit between the end support device and the runner, remove the other components of the center adjustment device, leaving only the block, and install the single-acting, thin-type jack between the block and the runner; install a dial indicator on the foundation ring, near the block, and away from the working direction; push the runner according to the calculation method in step 3.4) and use the dial indicator to monitor the runner center;

[0037] Step 4.5), the final wheel level θ≤0.02mm / m, the wheel center (db) / 2≤0.15mm, (ca) / 2≤0.15mm, the adjustment is qualified.

[0038] A device for adjusting the center and level of a runner of a large-scale Francis turbine comprises a block fixed on a base ring, a center adjustment screw being threadedly connected to the block, an end support device being installed at the end of the center adjustment screw, and the end support device performing center positioning and guiding on the runner.

[0039] The stopper is L-shaped, with bevels on the left and right sides of the horizontal portion of the lower end of the stopper, and a threaded through hole on the vertical portion of the upper end of the stopper.

[0040] The end support device includes a support plate and a sliding copper shoe, and the support plate and the sliding copper shoe are connected by hexagon socket countersunk bolts.

[0041] A shift rod hole is provided on the side wall of the support plate.

[0042] The present invention provides a method and device for adjusting the center and level of a large-scale Francis turbine runner, which has the following technical effects:

[0043] 1) This method uses a formula to calculate the thickness of pads in all directions when the runner is adjusted horizontally. The calculation method is reliable and can be copied to an EXCEL table for calculation. It has strong operability and has been put into practice in the maintenance of a power station unit. It is completely feasible.

[0044] 2) This method uses a wheel center auxiliary adjustment device to pre-control the wheel center, which can make the wheel center within the allowable deviation of the target value and reduce the number and amount of adjustments.

[0045] 3) After the runner is adjusted to the level, this method can avoid repeatedly raising and lowering the runner to adjust the runner center. The adjustment value is quantified and accurately adjusted, and basically the adjustment can be successful in one go, which improves work efficiency and saves human resources. It has been put into practice in the maintenance of a power station unit and is completely feasible. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The present invention will be further described below with reference to the accompanying drawings and examples:

[0047] Figure 1 It is the front view of the center adjustment device in the present invention.

[0048] Figure 2 It is a left view of the center adjustment device in the present invention.

[0049] Figure 3 It is the front view of the stopper in the present invention.

[0050] Figure 4 It is a front view of the end support device in the present invention.

[0051] Figure 5 It is a schematic diagram of the working state of the present invention.

[0052] Figure 6 for Figure 5 A partial enlarged schematic diagram.

[0053] Figure 7 This is a plan view of the measurement point / wedge plate distribution in the present invention.

[0054] In the figure: wheel 1, bottom ring 2, auxiliary bottom ring 3, lower fixed leak-proof ring 4, lower rotating leak-proof ring 5, wedge plate 6, center adjustment device 7, single-acting thin hydraulic jack 8, base ring 9, coincidence level 10, block 7-1, center adjustment screw 7-2, end support device 7-3, first locking nut 7-4, second locking nut 7-5, groove 7-1-1, threaded through hole 7-1-2, screw section 7-2-1, adjustment square 7-2-2, support plate 7-3-1, sliding copper washer 7-3-2, lever hole 7-3-3, hexagon socket countersunk bolt 7-3-4. DETAILED DESCRIPTION

[0055] like Figure 1-4 As shown, a large-scale Francis turbine runner center adjustment device is mainly composed of a stopper 7-1, a center adjustment screw 7-2, an end support device 7-3, a first locking nut 7-4 and a second locking nut 7-5.

[0056] The stopper 7-1 is an L-shaped structure. Bevels 7-1-1 are provided at the weld points between the lower horizontal section of the stopper 7-1 and the base ring. The bevels 7-1-1 have a slope of 45° and a width of 5 to 10 mm. A threaded through hole 7-1-2 is provided transversely in the upper vertical section of the stopper 7-1. The threaded through hole 7-1-2 is primarily used to connect to a center adjustment screw 7-2.

[0057] The adjustment screw 7-2 is a special screw structure, primarily composed of a screw segment 7-2-1 and an adjustment square 7-2-2. Screw segment 7-2-1 is used to connect the stopper 7-1 and the end support device 7-3 and is a fully threaded screw. The adjustment square 7-2-2 has a square head structure, primarily facilitating the forward and backward movement of screw segment 7-2-1.

[0058] The end support device 7-3 is primarily composed of a support plate 7-3-1 and a sliding copper washer 7-3-2. The support plate 7-3-1 and the sliding copper washer 7-3-2 are connected by four hexagon socket countersunk bolts 7-3-4. A lever hole 7-3-3 is provided on the side wall of the support plate 7-3-1. This lever hole 7-3-3 facilitates the insertion of a rod and drives the support plate 7-3-1 to rotate, thereby completing the installation and removal of the support plate. The end support device 7-3 has two main functions: 1) controlling the center of the wheel 1 during its descent; and 2) transmitting the force of the single-acting thin jack 8 during the center adjustment of the wheel 1.

[0059] The stopper 7-1 is connected to the center adjustment screw 7-2 by a thread, and a second locking nut 7-5 is used to strengthen the force. The end support device 7-3 is connected to the center adjustment screw 7-2 by a thread, and a first locking nut 7-4 is used to strengthen the force.

[0060] A method for adjusting the center and level of a large Francis turbine runner. Before overhaul, the runner lower ring is lowered onto a wedge plate on the foundation ring through force conversion. After the repair, when the runner is hoisted in, the runner center, level, and elevation must be adjusted to within the required range to ensure smooth reinstallation of all unit components. Runner leveling is achieved by measuring four symmetrical positions on the runner or main shaft flange using a combined level, with the final combined level ≤0.02mm / m. Runner centering is achieved by measuring the gap between the lower stop ring and calculating the runner center deviation, with a center deviation of ≤0.15mm.

[0061] A method for adjusting the center and level of a runner of a large Francis turbine unit comprises the following steps:

[0062] Step 1) Measurement before repair: Measure the gap of the leak-proof ring before repair as a reference for reinstallation after repair, to check data and monitor wheel deformation; measure the level of the wheel before repair as a basis for adjusting the level when adding pads after reinstallation.

[0063] Step 1.1) When turning the car before repair, measure the gaps between the lower fixed stop ring 4 and the lower rotating stop ring 5, and record them as a1, b1, c1, and d1 (starting from the +Y direction, and moving clockwise as points a, b, c, and d respectively);

[0064] Step 1.2) Before repair, after the force conversion is completed, the weight of the runner 1 and the main shaft all falls on the wedge plates 6 corresponding to the base ring 9. Spot weld the wedge plates 6 and spot weld the wedge plates 6 to the base ring 9 firmly.

[0065] Step 1.3) Before repair, after the top cover and main shaft are lifted out and before the runner is lifted out, use a coincident level 10 to measure the runner level before repair in four directions symmetrical to the runner flange surface, avoiding the position of the runner lifting device. The level is recorded as θ (with the horizontal upward as positive) and the azimuth angle α (with the +X direction as 0° and counterclockwise as positive).

[0066] Step 2), initial level adjustment:

[0067] Step 2.1) Calculate the padding thickness of each wedge plate 6 based on the level of the runner before repair in step 1.3) and pad the wedge plate 6 with copper sheets;

[0068] Step 2.2), such as Figure 7 As shown, Figure 7 is the wedge plate distribution plan, the distribution angles of wedge plates 6#1 to 8# are denoted as β(n), β(n) is: 1# 90°, 2# 45°, 3# 0°... and so on; n is the wedge plate number;

[0069] Step 2.3), the theoretical adjustment height of each wedge plate 6 is δ(n)=-D / 2*θ*cos(α-β(n)), where D is the distribution diameter of the wedge plate. A positive calculated value indicates an upward adjustment;

[0070] Step 2.4), the final padding thickness of each wedge plate is Δ(n)=δ(n)+|Min{δ(n),n=1~8}|;

[0071] Step 2.5) Add copper padding on the wedge plate 6 according to the thickness of step 2.4). It is best if the copper padding covers the entire wedge plate 6.

[0072] Step 3), initial center adjustment:

[0073] Step 3.1), each unit uses 4 sets of center adjustment devices 7, and the 4 sets of center adjustment devices 7 are arranged along the upper, lower, left and right sides of the runner 1;

[0074] Step 3.2) Weld the stopper 7-1 of the center adjustment device 7 to the base ring 9 near the measuring hole of the lower rotating leak-proof ring 5;

[0075] Step 3.3) Before the runner 1 is hoisted into the pit, after adding the copper sheet as per step 2.5), apply grease or vaseline between the copper sheet and the runner;

[0076] Step 3.4) After the runner 1 is hoisted into the pit and lowered until the lower rotating leak-proof ring 5 is between 5 and 10 mm from the wedge plate 6, the center adjustment screw 7-2 of the rotating center adjustment device 7 is rotated so that each end support device 7-3 just touches the runner 1, thereby limiting and fixing the runner 1; measure the gap between the lower fixed leak-proof ring 4 and the lower rotating leak-proof ring 5, and record them as a2, b2, c2, and d2. At this time, the target gap of the runner in the x direction is x=(d2+b2) / 2, and the target gap in the y direction is y=(c2+a2) / 2;

[0077] Step 3.5) Adjust the top screws to move the center of the runner to the target center, and keep the bilateral clearance between each end support device and the runner at about 0.10mm;

[0078] Starting from the +y direction, clockwise, the adjustment amounts of each top screw are recorded as e, f, g, and h respectively;

[0079] The adjustment amount of the top screw in the +y direction is e=a2-y=(a2-c2) / 2-0.05. A positive value indicates that the top screw is extending away from the center of the wheel.

[0080] The adjustment amount of the top screw in the +x direction is f=b2-x=(b2-d2) / 2-0.05. A positive value indicates that the top screw is extending away from the center of the runner.

[0081] - The adjustment amount of the top screw in the y direction is g=c2-y=(c2-a2) / 2-0.05. A positive value indicates that the top screw is extending away from the center of the wheel.

[0082] - The adjustment amount of the top screw in the x-direction is h=d2-y=(d2-b2) / 2-0.05. A positive value indicates that the top screw is extending away from the center of the wheel.

[0083] Step 3.6) Continue to lower the runner until the weight of the runner 1 falls entirely on the wedge plate 6.

[0084] Step 4), level, center measurement and fine adjustment:

[0085] Step 4.1) Measure and calculate the level of the runner according to step 1.3); Measure and calculate the center of the runner according to step 3.4);

[0086] Step 4.2) If the wheel level is not qualified, calculate the amount of padding for the wedge plates in each direction according to Steps 2.2) to 2.5), lift the wheel 1 by 1 to 3 mm, and add copper sheets of corresponding thickness to the wedge plates 6; and control the center of the wheel according to Steps 3.1) to 3.5);

[0087] Step 4.3) If the runner center is unqualified, use the bridge crane to provide an upward lifting force F to the runner, so that the runner has a remaining force of about 50T, pressing on the wedge plate 6;

[0088] Step 4.4) Wheel Center Adjustment: Turn the center adjustment screws 7-2 on each center adjustment device 7 to their shortest position. Install a single-acting, thin-profile hydraulic jack 8 between the end support device 7-3 and the runner 1. If the single-acting, thin-profile hydraulic jack 8 is too thick to fit between the end support device 7-3 and the runner 1, remove the center adjustment screws 7-2 and the end support device 7-3, leaving only the stopper 7-1. Install the single-acting, thin-profile jack 8 between the stopper 7-1 and the runner 1. Install a dial indicator near the stopper 7-1. Move the runner 1 according to the calculation method in Step 3.4) and use the dial indicator to monitor the runner center.

[0089] Step 4.5), the final wheel level θ≤0.02mm / m, the wheel center |(db) / 2|≤0.15mm, |(ca) / 2|≤0.15mm, and the adjustment is qualified.

[0090] This method uses measurement and calculation followed by auxiliary adjustments to related devices. After initial and fine adjustments, the requirements can be met, thus avoiding the defects of repeated manual adjustments based on experience.

Claims

1. A method for adjusting the center and level of a large Francis turbine runner, comprising the following steps: Step 1), measurement before repair; Step 2) Initial level adjustment; Step 3) Initial center adjustment; Step 4), level, center measurement and fine adjustment; The step 1) includes the following steps: Step 1.1) When turning the car before repair, measure the gap between the lower fixed anti-leak ring (4) and the lower rotating anti-leak ring (5), and record them as a1, b1, c1, and d1; starting from the +Y direction, mark them as points a, b, c, and d in clockwise direction respectively; Step 1.2), before repair, after the force conversion is completed, the weight of the runner (1) and the main shaft all falls on the wedge plate (6) corresponding to the base ring (9), and the adjacent wedge plates (6) are spot welded, and the wedge plates (6) and the base ring (9) are spot welded firmly; Step 1.3) Before repair, after the top cover and main shaft are hoisted out and before the runner is hoisted out, use the coincident level (10) to measure the horizontal angle of the runner before repair in four directions symmetrical to the flange surface of the runner, avoiding the position of the runner hoist, and record it as θ, and the azimuth angle as α; The step 2) includes the following steps: Step 2.1) Calculate the padding thickness of each wedge plate (6) based on the horizontal angle before the runner is repaired in step 1.3), and pad the wedge plate (6) with copper; Step 2.2), the distribution angles of wedge plates #1 to #8 (6) are denoted as β(n); Step 2.3), the theoretical adjustment height of each wedge plate (6) is δ(n)=-D / 2*θ*cos(α-90°), where D is the distribution diameter of the wedge plate (6), and a positive calculated value indicates an upward adjustment; Step 2.4), the final padding thickness of each wedge plate is Δ=δ(n)+|Min{δ(n),n=1~8}|; Step 2.5) Add copper padding to the wedge plate according to the thickness of step 2.4). It is best if the copper padding covers the entire wedge plate (6).

2. The method for adjusting the center and level of a large-scale Francis turbine runner according to claim 1, wherein step 3) comprises the following steps: Step 3.1), each unit uses 4 sets of center adjustment devices (7), and the 4 sets of center adjustment devices (7) are evenly distributed circumferentially; Step 3.2), weld the stopper (7-1) of the center adjustment device (7) to the base ring (9) near the measuring hole of the lower rotating leak-proof ring (5); Step 3.3) Before the runner is hoisted into the pit, after adding copper padding as per step 2.5), apply grease or vaseline between the copper padding and the runner; Step 3.4), hoist the runner into the pit and drop it down until the distance between the lower rotating leak-proof ring (5) and the wedge plate (6) is between 5 and 10 mm, adjust the center adjustment screw (7-2) of the center adjustment device (7) so that the end support device (7-3) of each center adjustment device (7) just touches the runner (1), fix the runner (1) and measure the gap between the lower fixed leak-proof ring (4) and the lower rotating leak-proof ring (5), which are recorded as a2, b2, c2, and d2. At this time, the target gap of the runner in the x direction is x=(d2+b2) / 2, and the target gap in the y direction is y=(c2+a2) / 2; Step 3.5), adjust each center adjustment device (7), push the center of the wheel to the target center, and keep the bilateral gap between the end of each center adjustment device (7) and the wheel at 0.10mm; Step 3.6), continue to lower the wheel (1) until the weight of the wheel (1) falls entirely on the wedge plate (6).

3. According to the method for adjusting the center and level of a large-scale Francis turbine runner in claim 2, the adjustment amounts of the center adjustment screws (7-2) of each center adjustment device (7) in step 3.5) are respectively recorded as e, f, g, and h: The adjustment amount of the top screw in the +y direction is e=a2-y=(a2-c2) / 2-0.05; The adjustment amount of the top screw in the +x direction is f=b2-x=(b2-d2) / 2-0.05; -The adjustment amount of the top screw in the y direction is g=c2-y=(c2-a2) / 2-0.05; -The adjustment amount of the top screw in the x direction is h=d2-y=(d2-b2) / 2-0.

05.

4. The method for adjusting the center and level of a large Francis turbine runner according to claim 3, wherein step 4) comprises the following steps: Step 4.1) Measure and calculate the level of the runner according to step 1.3); Measure and calculate the center of the runner according to step 3.4); Step 4.2) If the wheel level is not qualified, calculate the amount of padding for the wedge plates in each direction according to steps 2.2) to 2.5), lift the wheel (1) by 1 to 3 mm, and add copper sheets of corresponding thickness to the wedge plates (6); and control the center of the wheel according to steps 3.1) to 3.5); Step 4.3) If the runner center is unqualified, use the bridge crane to apply an upward force F to the runner so that the runner has a certain residual weight pressing on the wedge plate (6); Step 4.4), then adjust the center of the wheel: rotate the center adjustment screw (7-2) on each center adjustment device (7) to the shortest; set up a single-action thin hydraulic jack (8) between the end support device (7-3) and the wheel (1); if the single-action thin hydraulic jack (8) is too thick and cannot be installed between the end support device (7-3) and the wheel (1), the other components of the center adjustment device (7) can be removed, leaving only the block (7-1), and set up a single-action thin jack (8) between the block (7-1) and the wheel (1); and set up a dial indicator on the base ring, near the block, and avoiding the working direction; according to the calculation method of step 3.4), push the wheel (1) and use the dial indicator to monitor the center of the wheel; Step 4.5), the final wheel level θ≤0.02mm / m, the wheel center (db) / 2≤0.15mm, (ca) / 2≤0.15mm, the adjustment is qualified.

5. A device for adjusting the center of a large Francis turbine runner for realizing the method for adjusting the center and level of a large Francis turbine runner according to claim 4, characterized in that: The invention comprises a stopper (7-1), the stopper (7-1) is fixed on a base ring (9), a center adjustment screw (7-2) is threadedly connected to the stopper (7-1), an end support device (7-3) is installed at the end of the center adjustment screw (7-2), and the end support device (7-3) performs center positioning and guidance on the rotating wheel (1).

6. A large-scale Francis turbine runner center adjustment device according to claim 5, characterized in that: The stopper (7-1) is L-shaped, with bevels (7-1-1) provided on the left and right sides of the horizontal portion of the lower end of the stopper (7-1), and a threaded through hole (7-1-2) provided on the vertical portion of the upper end of the stopper (7-1).

7. A large-scale Francis turbine runner center adjustment device according to claim 6, characterized in that: The end support device (7-3) comprises a support plate (7-3-1) and a sliding copper tile (7-3-2), and the support plate (7-3-1) and the sliding copper tile (7-3-2) are connected via a hexagon socket countersunk bolt (7-3-4).

8. The large-scale Francis turbine runner center adjustment device according to claim 7, characterized in that: A lever hole (7-3-3) is provided on the side wall of the support plate (7-3-1).

Images