Main shaft connecting structure of water turbine and generator

Abstract

The utility model relates to the technical field of installation and maintenance of water-turbine generator sets, and discloses a spindle connecting structure of a water turbine and a generator, an upper connecting flange is fixed at the upper end of a spindle of the water turbine, a lower connecting flange is fixed at the lower end of a spindle of the generator, and the upper connecting flange and the lower connecting flange are provided with threaded through holes which are arranged at equal intervals and annularly arrayed. The threaded through holes are matched with coupling bolts, a plurality of radial perforation pin holes matched with pin shafts are formed in the upper connecting flange and the lower connecting flange, a plurality of positioning units are arranged on the upper connecting flange and the lower connecting flange, and the positioning units are located between the adjacent threaded through holes. The positioning unit comprises an upper positioning unit arranged on the outer circumferential surface of the upper connecting flange and a lower positioning unit arranged on the outer circumferential surface of the lower connecting flange, and the upper positioning unit corresponds to the lower positioning unit. According to the utility model, the problems of higher unit fault occurrence rate and shortened service life caused by on-site drilling in the detection and maintenance process of the large hydro-generator in the background technology are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of installation and maintenance of a water turbine generator set, in particular to a main shaft connection structure of a water turbine and a generator. Background Art

[0002] Hydropower generation is a technology that uses the kinetic energy of water to convert it into electrical energy. Its core equipment is the turbine and generator. The turbine rotates under the impact of the water flow, converting water energy into mechanical energy, and then transmits the mechanical energy to the generator through the main shaft, thereby generating electrical energy. The main shaft is an important connecting component between the turbine and the generator. There is a way to transmit torque between the two flanges of the turbine main shaft and the generator main shaft. This is done by drilling and reaming a saddle pin hole between the flange surfaces of the two main shafts and using a cylindrical pin. The stability and reliability of the connection directly affects the operating efficiency and safety of the hydropower generator set.

[0003] In order to ensure the power generation of hydropower, in 2019, my country broke through key technologies and developed the world's first million-kilowatt hydropower generator set, and began to put it into use in large-scale hydropower stations. After years of operation, the saddle pins are often squeezed and deformed and cannot be used normally. If it is a traditional water turbine, it will be disassembled and returned to the factory for repair. However, the water turbine generator set in this plan is huge and cannot be returned to the factory for repair. Therefore, the applicant adopts a simpler and faster on-site drilling method, which greatly reduces the downtime and investment cost of the generator set; however, after a period of operation, it is found that the generator set after on-site drilling and maintenance has a higher failure rate and shortened service life. In order to ensure the power generation efficiency and economy of the generator set, the company urgently needs to solve this problem. Utility Model Content

[0004] The utility model aims to provide a main shaft connection structure of a water turbine and a generator, so as to solve the problems in the background technology that the failure rate of large-scale water turbine generators is higher and the service life is shortened due to on-site drilling during the inspection and maintenance process.

[0005] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a main shaft connection structure of a turbine and a generator, an upper connecting flange is fixed to the upper end of the turbine main shaft, and a lower connecting flange is fixed to the lower end of the generator main shaft, the upper connecting flange and the lower connecting flange are both provided with threaded through holes with equal spacing and in an annular array, the threaded through holes cooperate with the coupling bolts, and the upper connecting flange and the lower connecting flange are provided with a plurality of radial saddle pin holes that cooperate with the pin shafts, the upper connecting flange and the lower connecting flange are provided with a plurality of positioning units, the positioning units are located in the middle position of adjacent threaded through holes, the positioning units include an upper positioning unit arranged on the outer circumferential surface of the upper connecting flange and a lower positioning unit arranged on the outer circumferential surface of the lower connecting flange, and the upper positioning unit and the lower positioning unit correspond to each other.

[0006] The beneficial effects of this program are:

[0007] In the background technology, the applicant selected the on-site drilling maintenance method to reduce the downtime and investment cost of the generator set. However, the generator set after maintenance had the problems of high failure rate and shortened service life. Later, the applicant found that: due to the huge torque between the turbine shaft and the generator shaft of the million-kilowatt hydropower generator set, in order to ensure stable transmission between the two, more dense bolts are connected on the flange between the two. At the same time, due to the huge equipment of the generator set, the connection between the turbine shaft and the generator shaft of the hydropower generator set is relatively high from the ground, usually about 2-3 meters. The operator needs to work in mid-air. When drilling and reaming the saddle pin holes directly on site, the maintenance personnel need to spend a lot of time to accurately locate the new saddle pin hole position and then drill. In addition, there is a tendency for deviation in the process of locating the position, which may cause the coupling bolts on both sides to be accidentally damaged during the subsequent drilling and reaming of the pin holes, resulting in damage to the coupling bolts, an increase in the number of failures of the generator set during subsequent operation, and a shortened service life of the corresponding parts.

[0008] Therefore, in order to solve the above problems, the utility model provides a positioning unit at the middle position of adjacent threaded through holes, and the positioning unit includes an upper positioning unit and a lower positioning unit respectively arranged on the outer circumferential surface of the upper connecting flange and the lower connecting flange. When the equipment is inspected and repaired after a long period of operation, the positioning unit is used as the position basis for the processing of the saddle pin hole. The utility model can directly select the orientation of the new saddle pin hole on site and then perform the pin hole processing on site based on the positioning unit at the orientation. Compared with the background technology in which the position is accurately found on site and then the drilling processing is performed, the utility model effectively improves the accuracy of on-site drilling by pre-arranging the positioning unit on the entire connecting structure of the turbine and the generator main shaft, avoids accidental damage to the coupling bolts on both sides during drilling and reaming, ensures the stability and reliability of the entire connecting structure, saves maintenance time, greatly shortens the unit downtime and cost, and improves the maintenance efficiency; at the same time, the positioning unit also serves as an installation guide for the equipment. The operator can observe from the outside of the two main shafts whether the upper positioning unit and the lower positioning unit are installed in alignment, and further judge whether the installation position is accurate, making the equipment installation easier and faster.

[0009] Furthermore, the positioning unit is a concave structure.

[0010] The above-mentioned setting of the positioning unit as a concave structure is to enable the drilling and reaming drill bit to be directly placed in the positioning unit for positioning during on-site drilling and reaming processing, thereby ensuring the drilling and reaming accuracy and saving maintenance time and cost.

[0011] Furthermore, the concave structure is cylindrical, conical, hemispherical or a combination of two of these structures.

[0012] The above-mentioned concave structure can be in various shapes, which makes it easy to select the drilling and reaming drill bit according to actual needs, making the entire solution more practical.

[0013] Furthermore, the depth of the positioning unit is 5-10 mm.

[0014] The depth of the positioning unit is set within the above range to achieve the processing positioning of the saddle pin hole. When the depth is less than the above range, the drill bit cannot be positioned. When the depth is greater than the above range, the entire connection structure is greatly damaged, affecting the transmission stability of the connection structure during actual operation.

[0015] Furthermore, the circumferential dimension of the positioning unit is 20-50 mm.

[0016] The circumferential dimension of the positioning unit is set within the above range to prevent the size from being too small and becoming blurred due to corrosion and wear in the natural environment during the use of the equipment and unable to play a positioning processing role; secondly, to prevent the size from being too large and unable to play a positioning role. At the same time, too large a size will also affect the structure and quality of the subsequent processing of the saddle pin hole and the coordination between the saddle pin hole and the pin shaft.

[0017] Furthermore, there are two or more threaded through holes between adjacent saddle pin holes.

[0018] The above arrangement is to disperse the adjacent saddle pin holes to ensure more torque transmission angles and better transmission efficiency.

[0019] Furthermore, the saddle pin hole comprises a first rectangular pin hole and a second circular pin hole, and a rectangular pin shaft and a circular pin shaft of the same shape are installed in the first pin hole and the second pin hole.

[0020] In the above arrangement, the circular pin shaft cooperates with the second pin hole, and the rectangular pin shaft cooperates with the first pin hole to realize torque transmission, thereby reducing the deformation degree of the coupling bolt due to torque. At the same time, the circular pin shaft and the rectangular pin shaft are two independent parts, which can be separately inspected and replaced, thereby reducing the inspection and maintenance cost. Secondly, the circular pin shaft cooperates with the second pin hole to serve as an installation guide for the equipment, thereby ensuring the efficiency and accuracy of the equipment installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure in the first embodiment of the present invention, looking down from the generator main shaft to the turbine main shaft.

[0022] Figure 2 for Figure 1 Cross-sectional view along AA direction.

[0023] Figure 3 It is a schematic diagram of the structure of the second embodiment of the present invention, looking down from the generator main shaft to the turbine main shaft.

[0024] Figure 4 for Figure 1 Cross-sectional view along BB direction

[0025] Figure 5 It is a schematic diagram of the structure of the cooperation between the saddle pin hole and the pin shaft in the embodiment of the utility model. DETAILED DESCRIPTION

[0026] The following is further described in detail through specific implementation methods:

[0027] The figure marks in the drawings of the specification include: turbine main shaft 1, upper connecting flange 2, generator main shaft 3, lower connecting flange 4, threaded through hole 5, coupling bolt 6, saddle pin hole 7, first pin hole 71, rectangular pin shaft 72, second pin hole 73, circular pin shaft 74, positioning unit 8, upper positioning unit 81, lower positioning unit 82.

[0028] Embodiment 1

[0029] like Figure 1-Figure 2 As shown, a main shaft connection structure of a turbine and a generator comprises a detachably connected turbine main shaft 1 and a generator main shaft 3, an upper connecting flange 2 is welded and fixed to the upper end of the turbine main shaft 1, and a lower connecting flange 4 is welded and fixed to the lower end of the generator main shaft 3, and a plurality of threaded through holes 5 with equal spacing and in a circular array are provided on the upper connecting flange 2 and the lower connecting flange 4, a coupling bolt 6 passes through the threaded through holes 5 of the upper connecting flange 2 and the lower connecting flange 4 and cooperates with a nut to fix the upper connecting flange 2 and the lower connecting flange 4, a plurality of radial saddle pin holes 7 are opened on the upper connecting flange 2 and the lower connecting flange 4, the saddle pin holes 7 are cooperated with a circular pin shaft, each saddle pin hole 7 is located in the middle position of adjacent threaded through holes 5, and the number of threaded through holes 5 between adjacent saddle pin holes 7 is not less than two, and the number of saddle pin holes 7 in this embodiment is two.

[0030] like Figure 1 As shown, the upper connecting flange 2 and the lower connecting flange 4 are provided with a plurality of positioning units 8 for machining and positioning the saddle pin holes 7. The positioning units 8 are located in the middle of two adjacent threaded through holes 5, and the axis of the positioning units 8 in the depth direction coincides with the symmetry axis between the two adjacent threaded through holes 5 and is perpendicular to the axis of the turbine main shaft 1; Figure 2As shown, the positioning unit 8 includes an upper positioning unit 81 arranged on the outer circumferential surface of the upper connecting flange 2 and a lower positioning unit 82 arranged on the outer circumferential surface of the lower connecting flange 4. The upper positioning unit 81 corresponds to the lower positioning unit 82 and has the same symmetrical structure. A guide line (not shown in the figure) is arranged on the upper surface of the upper connecting flange 2 along the axial direction of the positioning unit 8. The guide line is used for auxiliary guidance of the drilling equipment during on-site drilling to prevent drilling deviation. The number of guide lines corresponds to the number of positioning units 8. The implementation form of the guide line includes a groove structure or drawing with spray paint. Drawing the guide line with spray paint is more convenient, but it is easy to be blurred by wind and frost erosion. The guide line is a groove structure, which can effectively avoid erosion caused by the equipment being outdoors for a long time, resulting in blurring and inability to guide drilling.

[0031] like Figure 1 , Figure 2 As shown, the size of the positioning unit 8 along the radial direction of the upper connecting flange 2 is 5-10mm, so as to ensure that the positioning unit 8 plays a role in positioning processing while reducing the opening area of ​​the connecting structure and ensuring the transmission stability of the connecting structure. The aperture size of the positioning unit 8 is 20-50mm, so as to ensure that the drill bit is positioned while reducing the processing amount; the positioning unit 8 is a concave structure, a convex structure or a combination of the two. In this embodiment, the positioning unit 8 is a concave structure, and the drill bit is located in the concave structure to make the positioning processing more accurate; further, the concave structure includes a cylindrical, conical or hemispherical shape and a combination of a cylindrical, conical, and hemispherical shape. In this embodiment, the concave structure is a conical shape. Compared with the cylindrical and hemispherical shapes, the concave concave structure of the concave shape fits the end shape of the drill bit more closely, so that the contact between the drill bit and the concave structure is more stable, the positioning effect is better, and the drilling accuracy is higher; the structure of the positioning unit 8 does not affect the use of the coupling bolt 6, and the saddle pin hole 7 is reprocessed and positioned in advance during subsequent maintenance, which saves maintenance time and improves maintenance efficiency.

[0032] The specific implementation process is as follows:

[0033] During installation, the threaded through holes 5 on the upper connecting flange 2 and the lower connecting flange 4 are made to correspond to each other through the lifting device, and at the same time, the partial pin hole structures on the upper connecting flange 2 and the lower connecting flange 4 are ensured to correspond to each other to form a complete saddle pin hole 7, and the upper positioning unit 81 corresponds to the lower positioning unit 82, and then the upper connecting flange 2 and the lower connecting flange 4 are preliminarily fixed using the coupling bolts 6 and nuts; check and adjust the concentricity of the turbine main shaft 1 and the generator main shaft 3 until the concentricity reaches the predetermined requirement, and then tighten the coupling bolts 6; then install the pin shaft into the saddle pin hole 7, so that the pin shaft is tightly attached to the upper connecting flange 2 and the lower connecting flange 4 to ensure torque transmission and realize the connection between the turbine main shaft 1 and the generator main shaft 3.

[0034] During inspection and maintenance, there is no need to disassemble the equipment and return it to the factory to reconfirm the processing position of the saddle pin hole 7. It is only necessary to reselect the new position of the saddle pin hole 7 according to the actual situation, and then align the drill bit of the drilling and reaming device with the positioning unit 8 at that position for on-site processing. The guide line is used as an auxiliary guide for drilling. After the saddle pin hole 7 is processed, the pin shaft can be installed.

[0035] Embodiment 2

[0036] like Figure 3-Figure 5 As shown, the saddle pin hole 7 includes a rectangular first pin hole 71 and a circular second pin hole 73. The first pin hole 71 is connected to the second pin hole 73. A rectangular pin shaft and a circular pin shaft of the same shape are installed in the first pin hole 71 and the second pin hole 73.

[0037] During the specific installation, after the lifting device makes the upper positioning unit 81 and the lower positioning unit 82 correspond, the circular pin shaft 74 is placed in the second pin hole 73 of the upper connecting flange 2, and the lower connecting flange 4 is placed on the upper connecting flange 2 through the cooperation of the circular pin shaft 74 and the second pin hole 73, and then the upper connecting flange 2 and the lower connecting flange 4 are preliminarily fixed using the coupling bolts 6 and nuts; check and adjust the concentricity of the turbine main shaft 1 and the generator main shaft 3 until the concentricity reaches the predetermined requirement, and then tighten the coupling bolts 6; then evenly drive the rectangular pin shaft 72 into the first pin hole 71, so that the rectangular pin shaft 72 is tightly attached to the upper connecting flange 2 and the lower connecting flange 4 to ensure torque transmission and realize the connection between the turbine main shaft 1 and the generator main shaft 3.

[0038] During maintenance, the new saddle pin hole 7 formed by on-site drilling in this embodiment is a circular pin hole as a whole.

[0039] The above is only an embodiment of the utility model, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the utility model, several deformations and improvements can be made, which should also be regarded as the protection scope of the utility model, and these will not affect the effect of the implementation of the utility model and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A main shaft connection structure of a turbine and a generator, wherein an upper connecting flange is fixed to the upper end of the turbine main shaft, and a lower connecting flange is fixed to the lower end of the generator main shaft, and both the upper connecting flange and the lower connecting flange are provided with threaded through holes with equal spacing and an annular array, the threaded through holes are matched with coupling bolts, and a plurality of radial saddle pin holes matched with pin shafts are opened on the upper connecting flange and the lower connecting flange, characterized in that: A plurality of positioning units are provided on the upper connecting flange and the lower connecting flange. The positioning units are located in the middle of adjacent threaded through holes. The positioning units include an upper positioning unit provided on the outer circumferential surface of the upper connecting flange and a lower positioning unit provided on the outer circumferential surface of the lower connecting flange. The upper positioning unit corresponds to the lower positioning unit.

2. A main shaft connection structure of a water turbine and a generator according to claim 1, characterized in that: The positioning unit is a concave structure.

3. A main shaft connection structure of a water turbine and a generator according to claim 2, characterized in that: The concave structure is cylindrical, conical, hemispherical or a combination of two of these structures.

4. A main shaft connection structure of a water turbine and a generator according to claim 2, characterized in that: The depth of the positioning unit is 5-10 mm.

5. The main shaft connection structure of a water turbine and a generator according to claim 2, characterized in that: The circumferential dimension of the positioning unit is 20-50 mm.

6. A main shaft connection structure of a water turbine and a generator according to claim 5, characterized in that: There are more than two threaded through holes between adjacent saddle pin holes.

7. A main shaft connection structure of a water turbine and a generator according to claim 6, characterized in that: The saddle pin hole comprises a first rectangular pin hole and a second circular pin hole, and a rectangular pin shaft and a circular pin shaft of the same shape are installed in the first pin hole and the second pin hole.

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