On-site recovery method for dynamic and static collision abrasion damage of steam turbine cylinder assembly

Abstract

The field recovery method for the dynamic and static collision abrasion damage of the steam turbine cylinder assembly comprises a radial steam seal recovery method, and the radial steam seal recovery method comprises the steps that in the cylinder combination and bolt hot tightening state, the cylinder left and right diameter measurement size, the cylinder upper and lower diameter measurement size and the cylinder inner opening at the damaged steam seal position are obtained; determining the actual processing diameter size of the cylinder at the damaged steam seal; the actual tooth height of the damaged steam seal before damage is determined; in the half-cylinder state, the new steam seal is used for replacing the damaged steam seal; the lower half steam seal center and the upper half steam seal center of the new steam seal are determined; inner edge reference positions of the new lower half steam seal and the new upper half steam seal are determined; the new steam seal is subjected to circumferential machining with the centers of the two half steam seals as the circle center, and the tooth height of the corresponding half steam seal at the inner edge reference position is the actual tooth height of the damaged steam seal; the actual machining diameter size of the steam cylinder at the damaged steam seal is reversely deduced according to the steam cylinder deformation rule, so that the actual tooth height of the damaged steam seal is accurately obtained, and one-time cutting of the steam seal is facilitated.

Description

Technical Field

[0001] This invention belongs to the field of steam turbine field restoration technology, specifically relating to a field restoration method for dynamic and static rubbing damage to steam turbine cylinder assemblies. Background Technology

[0002] During turbine operation, the rotor rotates at high speed, while the cylinder, stator vanes, and radial steam seals remain stationary. A proper clearance must be maintained between the rotor and stator to prevent rubbing between the rotor and stator. Therefore, when foreign objects enter the cylinder, they inevitably damage the clearance between the rotor and stator, causing rubbing and damaging the steam seals and / or stator vanes. In this case, the damaged components need to be replaced in a cold state, and the replaced components need to be cut to restore the turbine to its pre-damage condition.

[0003] However, in actual operation, it was found that the cylinder was subjected to different temperatures and pressures at different locations, resulting in varying degrees of deformation at different locations. Due to the deformation of the cylinder, it was difficult to control the cutting amount of the new replacement parts, requiring repeated adjustments and confirmations, which greatly affected the replacement cycle and cost of the damaged parts. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide an on-site restoration method for dynamic and static rubbing damage of a steam turbine cylinder assembly, which can accurately determine the cutting amount of the newly replaced parts, so as to overcome the shortcomings of traditional cutting amount control which is difficult to control and requires repeated adjustments.

[0005] To achieve the above and other related objectives, the present invention provides an on-site recovery method for dynamic and static rubbing damage of a steam turbine cylinder assembly. The cylinder assembly includes a cylinder, radial steam seals, and stationary vanes. The on-site recovery method includes a radial steam seal recovery method, which comprises:

[0006] With the cylinder in the closed and bolts hot-tightened state, obtain the cylinder's left and right diameter measurement L1, cylinder's upper and lower diameter measurement H1, and cylinder's inner opening C1 at the damaged steam seal location to determine the actual machined diameter D1 of the cylinder at the damaged steam seal location; the formula for determining the actual machined diameter D1 of the cylinder at the damaged steam seal location is: D1=(H1+L1-C1) / 2;

[0007] Based on the actual machined diameter D1 of the cylinder at the damaged steam seal and the ideal inner diameter d1 of the damaged steam seal, determine the actual tooth height h of the damaged steam seal before the damage; the actual tooth height h of the damaged steam seal before the damage is: h=(D1-d1) / 2;

[0008] In the half-cylinder state, the damaged steam seal is replaced with a new steam seal; the new steam seal includes a new upper half steam seal and a new lower half steam seal.

[0009] In the half-cylinder state, the new steam seal is centered to determine the center of the lower half steam seal and the center of the upper half steam seal. Using the two half steam seal centers as references, the inner edge reference positions of the new lower half steam seal and the new upper half steam seal are determined. The inner edge reference position is the inner edge position of each new half steam seal that is farthest from the corresponding half steam seal center.

[0010] In the half-cylinder state, the new steam seal is circumferentially machined with the centers of the two half-seals as the center, so that the tooth height of the corresponding half-seal at the inner edge reference position is the actual tooth height of the damaged steam seal, thus completing the on-site restoration of the damaged steam seal.

[0011] Preferably, the on-site restoration method includes a still blade restoration method, which includes:

[0012] In the half-cylinder state, the damaged stationary vane is replaced with a new stationary vane, and several normal stationary vanes are selected near the new stationary vane as the base stationary vane for the new stationary vane; the new stationary vane includes a new upper stationary vane and a new lower stationary vane.

[0013] Under the conditions of cylinder assembly and bolt hot tightening, obtain the cylinder opening at the new stationary vane, the cylinder opening at each base stationary vane, the left and right diameter measurement dimensions of each base stationary vane, and the top and bottom diameter measurement dimensions of each base stationary vane. Then, perform stationary vane centering on each base stationary vane to determine the stationary vane centerline of the lower and upper cylinders, and then determine the center of the lower and upper stationary vanes of the new stationary vane.

[0014] Based on the formula for the left-right deformation of the stator vanes, the left-right deformation of each basic stator vane is determined; then, considering the relative positional relationship between the new stator vane and each basic stator vane along the cylinder axis, the left-right deformation of the damaged stator vane before damage is determined, thereby determining the ideal left-right diameter of the new stator vane; the formula for the left-right deformation of the stator vanes is: a j =D2 j -L2 j In the formula, a j D2 represents the lateral deformation of the j-th level normal stationary blade. j L2 represents the actual machined diameter of the j-th level normal stator blade. j The left and right diameters of the j-th level normal stationary blade are measured.

[0015] With the cylinder in place and the bolts hot-tightened, the new stationary blade is circumferentially machined with the centers of the two half-stage stationary blades as the center and the ideal left and right diameters of the new stationary blade as the machining diameter.

[0016] Obtain the measured dimensions of the upper and lower diameters of the new stationary blade after machining, and determine whether the deviation between the measured dimensions of the new stationary blade and the ideal dimensions of the new stationary blade meets the tolerance requirements. If the tolerance requirements are met, the stationary blade restoration is completed. If the tolerance requirements are not met, the upper and lower positions of the center of the lower half of the stationary blade and / or the center of the upper half of the stationary blade are corrected, and the new stationary blade is re-machined and checked with the corrected half-stationary blade center as the center until the deviation between the measured dimensions of the upper and lower diameters of the new stationary blade and the ideal dimensions of the new stationary blade meets the tolerance requirements.

[0017] The method for determining the ideal upper and lower diameter dimensions of the new stationary blade is as follows:

[0018] The vertical deformation of each basic stator is determined based on the stator blade deformation formula; then, considering the relative positional relationship between the new stator blade and each basic stator blade in the cylinder axial direction, the vertical deformation of the damaged stator blade before damage is determined, thereby determining the ideal vertical diameter of the new stator blade; the stator blade vertical deformation formula is: b j =H2 j -D2 j -C2 j In the formula, b j D2 represents the vertical deformation of the j-th level normal stationary blade. j H2 represents the actual machined diameter of the j-th stage normal stator blade. j C2 is the measured dimension of the upper and lower diameters of the j-th level normal stator blade. j The cylinder opening is located at the j-th stage normal stationary vane.

[0019] Preferably, the plurality of basic stationary blades include normal stationary blades adjacent to the new stationary blades.

[0020] Preferably, the center line of the stationary vane of the lower cylinder is the line connecting the centers of the lower stationary vanes of each normal stationary vane, and the center line of the stationary vane of the upper cylinder is the line connecting the centers of the upper stationary vanes of each normal stationary vane.

[0021] Preferably, the three-point method is used for center finding.

[0022] Preferably, the centering instruments for the centering operation are a cylinder boring machine and a dial indicator.

[0023] As described above, the on-site recovery method for dynamic and static rubbing damage of a steam turbine cylinder assembly according to the present invention has the following beneficial effects:

[0024] This invention measures and calculates the machining cutting amount of the new replacement part based on the cylinder deformation, effectively overcoming the shortcomings of traditional cutting amounts that require repeated adjustments. Then, with the help of a cylinder boring machine and a dial indicator, the upper and lower centers of the new replacement part on the deformed cylinder are located and determined. This facilitates the subsequent circumferential machining of the new replacement part using the upper and lower centers as machining centers, thereby completing the efficient and accurate replacement of the damaged part and effectively shortening the turbine on-site restoration cycle. Attached Figure Description

[0025] Figure 1 This is a diagram of the cylinder in its cold state before deformation.

[0026] Figure 2 This is a diagram of the cylinder after deformation and cold assembly.

[0027] Figure 3 This is a cross-sectional view of the cylinder at the i-th stage steam seal before cylinder deformation.

[0028] Figure 4 This is a cross-sectional view of the cylinder after deformation at the i-th stage steam seal.

[0029] Figure 5 This is a cross-sectional view of the cylinder at the j-th stage steam seal before cylinder deformation.

[0030] Figure 6 This is a cross-sectional view of the cylinder after deformation at the j-th stage steam seal.

[0031] Figure 7 This is a schematic diagram of the centering process for the centering instrument.

[0032] Figure 8 for Figure 7 Enlarged view of point A.

[0033] Figure 9 This is a flowchart of the radial steam seal restoration method.

[0034] Figure 10 This is a flowchart of the method for restoring stagnant leaves.

[0035] Cylinder boring machine 01, cylinder 1, lower cylinder 1a, upper cylinder 1b, radial steam seal 2, lower steam seal 2a, upper steam seal 2b, stationary vane 3, lower stationary vane 3a, upper stationary vane 3b. Detailed Implementation

[0036] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0037] Please see Figures 1 to 10It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without impairing the effectiveness or purpose of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0038] The turbine cylinder assembly includes a cylinder 1, stator vanes 3 located within the cylinder 1, and radial steam seals 2 located within the cylinder 1; such as Figure 1 , Figure 2 , Figure 3 and Figure 5 As shown, cylinder 1 is formed by connecting the lower cylinder 1a and the upper cylinder 1b; radial steam seal 2 is formed by connecting the lower steam seal 2a and the upper steam seal 2b; and stationary vane is formed by connecting the lower stationary vane 3a and the upper stationary vane 3b. Initially, the lower cylinder 1a and the upper cylinder 1b are tightly fitted at the split surface, and the inner wall of cylinder 1 is generally circular. After the turbine has been running hot for a period of time, due to the influence of high-temperature and high-pressure steam, different parts of cylinder 1 will undergo varying degrees of deformation. When the deformed cylinder 1 is in a cold state, an inward opening phenomenon occurs at the mid-section of cylinder 1, causing the overall shape of the inner wall of cylinder 1 to change from a circle to a near-elliptical shape with the upper and lower diameters larger than the left and right diameters. When it is heated again, the inward opening phenomenon of cylinder 1 gradually disappears due to the increase in temperature, and cylinder 1 returns to a circle from a near-elliptical shape. When foreign objects enter the cylinder 1 in a hot state, it is very easy to cause dynamic and static collision and rubbing, which damages the radial steam seal 2 and / or stationary vane 3 inside cylinder 1. It is necessary to replace the damaged parts in time to restore the steam turbine to its optimal working state before the parts were damaged. However, due to the influence of temperature, the replacement and cutting of the radial steam seal 2 and / or stationary vane 3 inside cylinder 1 can only be carried out when the cylinder is cold. However, the cylinder 1 is deformed in the cold state, and it is impossible to accurately control the cutting amount, which greatly affects the replacement cycle of the damaged parts. This results in the disadvantages of difficult restoration of the steam turbine to its hot state and long restoration cycle.

[0039] Based on this, embodiments of the present invention disclose an on-site recovery method for dynamic and static rubbing damage of a steam turbine cylinder assembly, the on-site recovery method including a radial steam seal recovery method and / or a stationary blade recovery method.

[0040] (a) Radial steam seal restoration methods, such as Figure 9 As shown, it includes:

[0041] A1, such as Figure 4 As shown, under the condition of cylinder assembly and bolt hot tightening, the cylinder left and right diameter measurement dimensions L1, cylinder upper and lower diameter measurement dimensions H1, and cylinder inner opening C1 at the damaged steam seal are obtained to determine the actual machined diameter dimension D1 of the cylinder at the damaged steam seal; the formula for determining the actual machined diameter dimension D1 of the cylinder at the damaged steam seal is: D1=(H1+L1-C1) / 2;

[0042] By analyzing the deformation pattern of the cylinder, it was found that the vertical deformation of cylinder 1 is basically equal to the horizontal deformation. Therefore, the deformed cylinder satisfies the formula: D1-L1=H1-D1-C1, and the actual machining diameter D1 of cylinder 1 can be calculated as: D1=(H1+L1-C1) / 2.

[0043] A2. Based on the actual machined diameter D1 of the cylinder at the damaged steam seal and the ideal inner diameter d1 of the damaged steam seal, determine the actual tooth height h of the damaged steam seal before the damage; the actual tooth height h of the damaged steam seal before the damage is: h=(D1-d1) / 2;

[0044] The ideal inner diameter d1 of the damaged steam seal can be calculated based on the cylinder design diameter D0 at the damaged steam seal location and the corresponding design tooth height h0 of the damaged steam seal, satisfying d1 = D0 - 2 × h0. This invention obtains the actual cylinder diameter machining dimension D1 at the damaged steam seal location by reverse deduction of the cylinder deformation law, thereby accurately determining the actual tooth height h of the damaged steam seal before damage, providing a basis for the accurate determination of the subsequent steam seal cutting amount, thus effectively avoiding the problem of unreasonable steam seal radial clearance caused by directly cutting the steam seal based on the steam seal design tooth height.

[0045] A3. In the half-cylinder state, replace the damaged steam seal with a new steam seal; the new steam seal includes a new upper half steam seal and a new lower half steam seal;

[0046] A4. In the half-cylinder state, perform steam seal centering on the new steam seal to determine the center of the lower half steam seal and the center of the upper half steam seal; using the two half steam seal centers as references, determine the inner edge reference positions of the new lower half steam seal and the new upper half steam seal; where the inner edge reference position is the inner edge position on the inner wall of each new half steam seal that is farthest from the center of the corresponding half steam seal.

[0047] The three-point method is used for centering the steam seal. The centering instruments are a cylinder boring machine 01 and a dial indicator. The cylinder boring machine 01 is an existing device, which mainly includes a boring bar, a tool holder on the boring bar, a front support, and a rear support. The specific structure of the cylinder boring machine 01 can refer to existing steam turbine-specific boring machines such as the cylinder boring machine in CN201621371811.3 and the mobile boring equipment for steam turbine seal teeth in 201721230046.8. As long as it can meet the centering and boring requirements, it is acceptable.

[0048] like Figure 7 and Figure 8 As shown, when it is necessary to center the new lower half steam seal 2a, the cylinder boring machine 01 must first be supported in the lower half cylinder 1a, and a dial indicator should be installed on the boring shaft of the cylinder boring machine 01. The dial indicator is used to measure the radial dimensions of the new lower half steam seal in the left, lower, and right directions. The position of the cylinder boring machine is adjusted according to the radial dimensions in the three directions until the radial dimensions in the three directions are equal. At this time, the center of the new lower half steam seal (i.e., the center of the lower half steam seal) is the intersection of the boring shaft centerline and the thickness centering surface of the new lower half steam seal. Similarly, the center of the new upper half steam seal (i.e., the center of the upper half steam seal) can be determined.

[0049] The adjustment criteria for cylinder boring machines are as follows:

[0050] Assuming the radial dimensions of the new lower steam seal in the left, lower, and right directions are R1, R2, and R3 respectively, the horizontal deviation of the steam seal is (R1-R2) / 2, and the vertical deviation is R3-(R1+R2) / 2. If (R1-R2) / 2>0, it means the steam seal center is off to the left, and the boring bar needs to be moved to the left; if (R1-R2) / 2<0, it means the steam seal center is off to the right, and the boring bar needs to be moved to the right; if R3-(R1+R2) / 2>0, it means the steam seal center is too high, and the boring bar needs to be moved downward; if R3-(R1+R2) / 2<0, it means the steam seal center is too low, and the boring bar needs to be moved upward.

[0051] Because the cylinder may deform, resulting in localized bulges or depressions on its inner wall, the new steam seal will also deform and develop corresponding bulges or depressions when installed on the cylinder. In this case, the inner edge position furthest from the center of the new upper steam seal should be used as the reference position for the inner edge of the new upper steam seal, and the inner edge position furthest from the center of the new lower steam seal should be used as the reference position for the inner edge of the new lower steam seal. This ensures the accuracy of subsequent cutting measurements. In other words, when the inner wall of a half-seal deforms and becomes depressed, the position of the deepest depression is used as the reference position for the inner edge of the corresponding half-seal; when the inner wall of a half-seal does not deform and does not become depressed, the position furthest from the center of the half-seal is used as the reference position for the inner edge.

[0052] A5. In the half-cylinder state, take the center of each of the two half-seals as the center and perform circumferential machining on the new seal so that the tooth height of the corresponding half-seal at the inner edge reference position is the actual tooth height of the damaged seal, so as to complete the on-site restoration of the damaged seal.

[0053] Of course, if the damaged steam seal is only partially damaged, the actual tooth height h0 of the damaged steam seal can be measured directly in the half-cylinder state.

[0054] (II) Methods for restoring still leaves, such as Figure 10 As shown, it includes:

[0055] B1. In the half-cylinder state, replace the damaged stationary blade with a new stationary blade, and select several normal stationary blades near the new stationary blade as the base stationary blade for the new stationary blade; the new stationary blade includes a new upper stationary blade and a new lower stationary blade.

[0056] When selecting a base stationary blade, the normal stationary blade closest to the new stationary blade is preferred (i.e., the normal stationary blade adjacent to the new stationary blade is selected); the selected base stationary blades can be distributed on the same side or different sides of the new stationary blade, and there is no limitation on this; in this embodiment, the selected base stationary blades are preferably distributed on different sides of the new stationary blade; when there are multiple new stationary blades, there is a situation where the new stationary blades share the base stationary blade.

[0057] B2, such as Figure 6 As shown, under the condition of cylinder assembly and bolt hot tightening, the cylinder opening at the new stationary vane, the cylinder opening at each base stationary vane, the left and right diameter measurement dimensions of each base stationary vane, and the upper and lower diameter measurement dimensions of each base stationary vane are obtained. The stationary vane centering is performed on each base stationary vane to determine the stationary vane center lines of the lower half cylinder 1a and the upper half cylinder 1b, and then the center of the lower half stationary vane and the center of the upper half stationary vane of the new stationary vane are determined.

[0058] This embodiment also uses the three-point method to determine the center of the upper and lower half of the stationary blades of each foundation. The centering instruments are a cylinder boring machine 01 and a dial indicator. The centering principle is the same as that of the steam seal centering principle. The only difference is that the stationary blade centering is performed when the cylinder is closed and the bolts are hot-tightened, while the steam seal centering is performed when the cylinder is half open. The cylinder boring machine 01 is an existing device. Its structure can refer to the cylinder boring machine in CN201621371811.3 and the mobile boring equipment for steam turbine steam seal teeth in 201721230046.8, as long as it can meet the requirements of centering and boring. By fitting and connecting the centers of the upper half of each basic stator blade, the center line of the upper half of the cylinder stator blade can be determined. By fitting and connecting the centers of the lower half of each basic stator blade, the center line of the lower half of the cylinder stator blade can be determined. Then, by combining the relative positional relationship between the new stator blade and each basic stator blade in the axial direction, the center of the lower half of the new stator blade and the center of the upper half of the new stator blade can be determined.

[0059] When only two basic stator vanes are selected, the centers of the upper half of the two basic stator vanes can be directly connected by straight line fitting to form the stator vane centerline of the upper cylinder. When at least three basic stator vanes are selected, curve fitting is required to connect the centers of the upper half of each basic stator vane to form the stator vane centerline of the upper cylinder. The method for obtaining the stator vane centerline of the lower cylinder is the same as the method for obtaining the stator vane centerline of the upper cylinder.

[0060] B3. Based on the formula for the left-right deformation of the stator blades, determine the left-right deformation of each basic stator blade; then, combining the relative positional relationship between the new stator blade and each basic stator blade in the cylinder axial direction, determine the left-right deformation of the damaged stator blade before damage, and thus determine the ideal left-right diameter of the new stator blade; the formula for the left-right deformation of the stator blades is: a j =D2 j -L2 j In the formula, a j D2 represents the lateral deformation of the j-th level normal stationary blade. j L2 represents the actual machined diameter of the j-th level normal stator blade. j The left and right diameters of the j-th level normal stationary blade are measured.

[0061] In the field of steam turbines, the stationary vanes in cylinder 1 are usually numbered sequentially from level 1 to level n according to the axial direction of the cylinder, so as to facilitate the differentiation of the stationary vanes.

[0062] The left and right deformation of each basic stator blade can be calculated sequentially using the stator blade deformation formula. Then, the axial position of each basic stator blade on cylinder 1 and the left and right deformation of each basic stator blade are fitted to obtain the fitting relationship between the axial position of the normal stator blade and the left and right deformation. Based on this fitting relationship and the axial position of the damaged stator blade on cylinder 1, the left and right deformation of the damaged stator blade before damage can be determined. Then, based on the stator blade deformation formula, the left and right diameter measurements of the damaged stator blade before damage can be calculated. In order to better restore the hot operating state of the turbine, the new stator blade must be consistent with the state of the damaged stator blade before damage, that is, the ideal left and right diameter dimensions of the new stator blade must be the same as the left and right diameter measurements of the damaged stator blade before damage.

[0063] B4. With the cylinder in place and the bolts hot-tightened, take the centers of the two half-stove blades of the new stationary blade as the center and the ideal left and right diameters of the new stationary blade as the machining diameter, and perform circumferential machining on the new stationary blade.

[0064] B5. Obtain the measured dimensions of the upper and lower diameters of the new stationary blade after machining, and determine whether the deviation between the measured dimensions of the new stationary blade and the ideal dimensions of the new stationary blade meets the tolerance requirements. If the tolerance requirements are met, the new stationary blade is restored. If the tolerance requirements are not met, the upper and lower positions of the center of the lower half of the stationary blade and / or the center of the upper half of the stationary blade are corrected, and the new stationary blade is re-machined and checked with the corrected half-stationary blade center as the center until the deviation between the measured dimensions of the upper and lower diameters of the new stationary blade and the ideal dimensions of the new stationary blade meets the tolerance requirements.

[0065] The method for determining the ideal upper and lower diameters of the new stationary blade is as follows:

[0066] The vertical deformation of each basic stator is determined based on the stator blade deformation formula; then, considering the relative positional relationship between the new stator blade and each basic stator blade in the cylinder axial direction, the vertical deformation of the damaged stator blade before damage is determined, thereby determining the ideal vertical diameter of the new stator blade; the stator blade vertical deformation formula is: b j =H2 j -D2 j -C2 j In the formula, b j D2 represents the vertical deformation of the j-th level normal stationary blade. j H2 represents the actual machined diameter of the j-th stage normal stator blade. j C2 is the measured dimension of the upper and lower diameters of the j-th level normal stator blade. j The cylinder opening is located at the j-th stage normal stationary vane.

[0067] The vertical deformation of each base stator can be calculated sequentially using the stator blade deformation formula. Then, the axial position of each base stator on cylinder 1 and its vertical deformation are fitted to obtain a fitting relationship between the normal stator's axial position and its vertical deformation. Based on this fitting relationship and the axial position of the damaged stator on cylinder 1, the vertical deformation of the damaged stator before damage can be determined. Then, according to the stator blade deformation formula, the vertical diameter measurements of the damaged stator before damage are calculated. The ideal vertical diameter of the new stator is the same as that of the damaged stator before damage. To better restore the turbine to its hot operating state, the new stator must maintain the same state as the damaged stator before damage; that is, the deviation between the vertical diameter measurements of the new stator after machining and those of the damaged stator before damage must meet the tolerance requirements.

[0068] In summary, this invention, based on the cylinder deformation trend, measures and calculates the machining cutting amount of the new replacement component (stationary vane or steam seal), effectively overcoming the shortcomings of traditional cutting amounts which require repeated adjustments. Then, using a cylinder boring machine and a dial indicator, the upper and lower centers of the new replacement component on the deformed cylinder are located and determined. This facilitates subsequent circumferential machining of the new replacement component using the upper and lower centers as machining centers, enabling efficient and accurate replacement of damaged components. This effectively shortens the turbine on-site restoration cycle, greatly reduces the investment of manual labor and time, and facilitates widespread application.

[0069] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for on-site recovery of dynamic and static rubbing damage in a steam turbine cylinder assembly, wherein the cylinder assembly includes a cylinder, radial steam seals, and stationary vanes, characterized in that, The on-site restoration method includes a radial steam seal restoration method, which includes: With the cylinder in the closed and bolts hot-tightened state, obtain the cylinder's left and right diameter measurement L1, cylinder's upper and lower diameter measurement H1, and cylinder's inner opening C1 at the damaged steam seal location to determine the actual machined diameter D1 of the cylinder at the damaged steam seal location; the formula for determining the actual machined diameter D1 of the cylinder at the damaged steam seal location is: D1=(H1+L1-C1) / 2; Based on the actual machined diameter D1 of the cylinder at the damaged steam seal and the ideal inner diameter d1 of the damaged steam seal, determine the actual tooth height h of the damaged steam seal before the damage; the actual tooth height h of the damaged steam seal before the damage is: h=(D1-d1) / 2; In the half-cylinder state, the damaged steam seal is replaced with a new steam seal; the new steam seal includes a new upper half steam seal and a new lower half steam seal. In the half-cylinder state, the new steam seal is centered to determine the center of the lower half steam seal and the center of the upper half steam seal. Using the two half steam seal centers as references, the inner edge reference positions of the new lower half steam seal and the new upper half steam seal are determined. The inner edge reference position is the inner edge position of each new half steam seal that is farthest from the corresponding half steam seal center. In the half-cylinder state, the new steam seal is circumferentially machined with the centers of the two half-seals as the center, so that the tooth height of the corresponding half-seal at the inner edge reference position is the actual tooth height of the damaged steam seal, thus completing the on-site restoration of the damaged steam seal.

2. The method for on-site restoration of dynamic and static rubbing damage in a steam turbine cylinder assembly according to claim 1, characterized in that, The site restoration method includes a still leaf restoration method, which includes: In the half-cylinder state, the damaged stationary vane is replaced with a new stationary vane, and several normal stationary vanes are selected near the new stationary vane as the base stationary vane for the new stationary vane; the new stationary vane includes a new upper stationary vane and a new lower stationary vane. Under the conditions of cylinder assembly and bolt hot tightening, obtain the cylinder opening at the new stationary vane, the cylinder opening at each base stationary vane, the left and right diameter measurement dimensions of each base stationary vane, and the top and bottom diameter measurement dimensions of each base stationary vane. Then, perform stationary vane centering on each base stationary vane to determine the stationary vane centerline of the lower and upper cylinders, and then determine the center of the lower and upper stationary vanes of the new stationary vane. Based on the formula for the left-right deformation of the stator vanes, the left-right deformation of each basic stator vane is determined; then, considering the relative positional relationship between the new stator vane and each basic stator vane along the cylinder axis, the left-right deformation of the damaged stator vane before damage is determined, thereby determining the ideal left-right diameter of the new stator vane; the formula for the left-right deformation of the stator vanes is: a j =D2 j -L2 j In the formula, a j D2 represents the lateral deformation of the j-th level normal stationary blade. j L2 represents the actual machined diameter of the j-th level normal stator blade. j The left and right diameters of the j-th level normal stationary blade are measured. With the cylinder in place and the bolts hot-tightened, the new stationary blade is circumferentially machined with the centers of the two half-stage stationary blades as the center and the ideal left and right diameters of the new stationary blade as the machining diameter. Obtain the measured dimensions of the upper and lower diameters of the new stationary blade after machining, and determine whether the deviation between the measured dimensions of the new stationary blade and the ideal dimensions of the new stationary blade meets the tolerance requirements. If the tolerance requirements are met, the stationary blade restoration is completed. If the tolerance requirements are not met, the upper and lower positions of the center of the lower half of the stationary blade and / or the center of the upper half of the stationary blade are corrected, and the new stationary blade is re-machined and checked with the corrected half-stationary blade center as the center until the deviation between the measured dimensions of the upper and lower diameters of the new stationary blade and the ideal dimensions of the new stationary blade meets the tolerance requirements. The method for determining the ideal upper and lower diameter dimensions of the new stationary blade is as follows: The vertical deformation of each basic stator is determined based on the stator blade deformation formula; then, considering the relative positional relationship between the new stator blade and each basic stator blade in the cylinder axial direction, the vertical deformation of the damaged stator blade before damage is determined, thereby determining the ideal vertical diameter of the new stator blade; the stator blade vertical deformation formula is: b j =H2 j -D2 j -C2 j In the formula, b j D2 represents the vertical deformation of the j-th level normal stationary blade. j H2 represents the actual machined diameter of the j-th stage normal stator blade. j C2 is the measured dimension of the upper and lower diameters of the j-th level normal stator blade. j The cylinder opening is located at the j-th stage normal stationary vane.

3. The method for on-site restoration of dynamic and static rubbing damage in a steam turbine cylinder assembly according to claim 2, characterized in that, Multiple basic static leaves include normal static leaves adjacent to new static leaves.

4. The method for on-site restoration of dynamic and static rubbing damage in a steam turbine cylinder assembly according to claim 2, characterized in that, The center line of the stationary vane of the lower cylinder is the line connecting the centers of the lower stationary vanes of each basic stationary vane, and the center line of the stationary vane of the upper cylinder is the line connecting the centers of the upper stationary vanes of each basic stationary vane.

5. A method for on-site restoration of dynamic and static rubbing damage in a steam turbine cylinder assembly according to any one of claims 1 to 4, characterized in that, The three-point method is used for center finding.

6. The method for on-site restoration of dynamic and static rubbing damage in a steam turbine cylinder assembly according to claim 5, characterized in that, The centering instruments used in the centering operation are a cylinder boring machine and a dial indicator.

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