CN220279195U - Rotor blade grinding tool - Google Patents

Abstract

The utility model relates to a rotor blade grinding tool, which relates to the field of tool clamps and comprises a positioning main body, wherein a plurality of annular blade mounting grooves are formed in the side wall of the positioning main body, the plurality of blade mounting grooves are coaxial and are arranged at intervals along the axial direction of the positioning main body, and a weight reducing cavity is formed in the positioning main body. The beneficial effects of the utility model are as follows: the positioning main body is provided with a plurality of annular blade mounting grooves for simultaneously mounting the multistage blades, so that the multistage rotor blades can be ground and processed conveniently. The weight-reducing cavity is arranged in the positioning main body, so that the weight of the whole grinding tool is reduced, and the whole grinding tool can be applied to the existing grinding machine.

Description

Rotor blade grinding tool

Technical Field

The utility model relates to the field of tool clamps, in particular to a rotor blade grinding tool.

Background

When the gas turbine is maintained, the blade tips of the rotor blades of the 10-16-level gas compressor are required to be ground, so that the blade tips meet the length requirement, the blade is overlong, the casing is scratched, even the blade is broken and fails, and the working efficiency of the gas turbine is reduced when the blade is too short. During overhaul, the gas turbine is completely decomposed, and the rotor blade of the gas compressor is generally ground by taking the rotor as a tool; the compressor rotor assembly is not generally decomposed integrally during middle repair, so that only the compressor rotor blade can be independently decomposed for polishing repair, and the problems of low working efficiency and long time consumption of the grinding process of the compressor rotor blade all the time exist in the past. How to improve the grinding efficiency and ensure the grinding quality is the pursuit of the technician that the cumin is tireless.

The first generation of grinding was single piece hand-held grinding. The blade is held by an operator to polish on the belt type polisher, polishing is carried out while measurement is carried out, and the technical requirements of the inclination angle, the length and the like of the blade tip are controlled by means of personal operation level and experience. In the process implementation, the risk is high, the process quality is uncontrollable, and the rejection rate is 3%; the efficiency is low, and at least 400 working hours are required for finishing 522 blade grinding;

the second generation of grinding mode adopts a blade single-piece grinding device for grinding. The device has the advantages that the rotating state of the blade on the rotor of the compressor is simulated, the compressed air is used for driving the grinding wheel to polish, the inclination angle of the blade tip is guaranteed by adjusting the angle of the grinding wheel, the length of the blade is controlled by measuring the dial indicator in real time, and the quality risk in the operation process is reduced to a greater extent. The method is characterized in that manual operation is changed into mechanical operation, reliability and accuracy are improved, and rejection rate is reduced from 3% to 0. Because of still single-piece grinding, the working efficiency of the method is lower, and 160 man hours are needed for finishing the grinding work of all 522 blades;

the third generation grinding mode adopts a single-stage grinding tool for grinding. The improvement point is that the whole-stage polishing is realized, 76 sheets can be polished at one time, and the working efficiency is further improved. Firstly, because a single-stage polishing tool cannot completely simulate the running state of a rotor, deviation exists in blade length control, deviation amount needs to be reserved and process measurement is carried out, and potential quality hazards still exist; the second disadvantage is that only 1 stage blade can be installed each time, at least 7 times of installation are needed to finish grinding work of all 522 blades, the work efficiency is still lower, and 80 man hours are needed.

With the gradual increase of the maintenance amount of the gas turbine every year, the conventional grinding process cannot meet the actual production requirements on the length control and the working efficiency of the blade tip, and further improvement of the length control, the working efficiency, the grinding precision and the like of the blade tip is a technical problem to be solved urgently by the person skilled in the art.

Disclosure of Invention

The technical problem to be solved by the utility model is how to clamp the compressor rotor blade of a gas turbine.

The technical scheme for solving the technical problems is as follows: the utility model provides a rotor blade grinding frock, includes the location main part, location main part lateral wall has a plurality of annular blade mounting groove, a plurality of the blade mounting groove is coaxial and follow the axial interval setting of location main part, the inside lightening chamber that has of location main part.

The beneficial effects of the utility model are as follows: the positioning main body is provided with a plurality of annular blade mounting grooves for simultaneously mounting the multistage blades, so that the multistage rotor blades can be ground and processed conveniently. The weight-reducing cavity is arranged in the positioning main body, so that the weight of the whole grinding tool is reduced, and the whole grinding tool can be applied to the existing grinding machine.

On the basis of the technical scheme, the utility model can be improved as follows.

Further, the positioning main body comprises a plurality of positioning disks, each positioning disk is provided with one blade mounting groove on the outer wall, the positioning disks are coaxial and are fixedly connected in sequence along the axial direction of the positioning disks, and the weight reducing cavities are formed inside the positioning disks.

The beneficial effects of adopting the further scheme are as follows: a plurality of positioning disks are respectively processed and then fixedly connected together, so that the processing difficulty is effectively reduced.

Further, the positioning disk is annular, and an annular spoke disk is further fixed on the inner wall of the positioning disk.

The beneficial effects of adopting the further scheme are as follows: the spoke disc is arranged in the positioning disc, so that the thickness of the tooling is increased, and the structural strength of the tooling is further enhanced.

Further, a plurality of positioning disks are welded in sequence.

Further, each of the blade mounting grooves has a trapezoidal cross section.

Further, each of the blade mounting grooves is provided with an insertion groove along a radial direction thereof.

The beneficial effects of adopting the further scheme are as follows: when the rotor blade is mounted or dismounted, the rotor blade is inserted into or taken out of the blade mounting groove from the insertion groove.

Further, the insertion grooves are provided with locking grooves along both sides of the blade mounting groove in the circumferential direction, respectively.

The beneficial effects of adopting the further scheme are as follows: when the last rotor blades are installed, locking blocks are installed, and the locking blocks are clamped into the locking grooves to circumferentially position all the rotor blades.

Further, the rotor blade grinding tool further comprises a first shaft head and a second shaft head, and the first shaft head and the second shaft head are respectively fixed at two ends of the positioning main body.

The beneficial effects of adopting the further scheme are as follows: the rotor blade grinding tool is mounted to the grinding machine through a first spindle nose and a second spindle nose.

Further, the number of the blade mounting grooves is seven.

The beneficial effects of adopting the further scheme are as follows: seven blade mounting slots are correspondingly used for mounting 10-16 stage compressor rotor blades.

Further, the positioning body is made of 45# steel.

The beneficial effects of adopting the further scheme are as follows: the positioning main body adopts 45# steel, the Rockwell hardness is 32-35HRC, the tensile strength after tempering heat treatment can reach 1059MPA, the unit price is within 10 yuan/KG, the cost is low, the welding performance is good, the reliable connection can be realized by general argon arc welding, the requirements on the skill level of personnel are relatively low, and the problems of oxidization, air holes, lack of penetration and the like are difficult to occur.

Drawings

FIG. 1 is a cross-sectional view of a rotor blade grinding tool of the present utility model;

FIG. 2 is a schematic structural view of a rotor blade grinding tool assembled to a grinding machine fixture;

FIG. 3 is a partial cross-sectional view of a rotor blade grinding tool assembled with a rotor blade;

FIG. 4 is a schematic view of a three-dimensional partial structure of a puck;

FIG. 5 is a schematic view of a rotor blade assembly configuration;

FIG. 6 is an exploded view of a rotor blade assembly structure.

In the drawings, the list of components represented by the various numbers is as follows:

1. a positioning main body; 2. a blade mounting groove; 3. a weight-reducing cavity; 4. a positioning plate; 5. a spoke plate; 6. an insertion groove; 7. a locking groove; 8. a first stub shaft; 9. a second shaft head; 10. a common blade; 11. a first locking blade; 12. a second locking blade; 13. a locking piece; 14. and (5) balancing weights.

Detailed Description

The principles and features of the present utility model are described below with reference to the drawings, the examples are illustrated for the purpose of illustrating the utility model and are not to be construed as limiting the scope of the utility model.

As shown in fig. 1-6, the present embodiment provides a rotor blade grinding tool, which includes a positioning main body 1, wherein a plurality of annular blade mounting grooves 2 are provided on a side wall of the positioning main body 1, a plurality of blade mounting grooves 2 are coaxial and are arranged along an axial direction of the positioning main body 1 at intervals, and a weight reduction cavity 3 is provided inside the positioning main body 1.

The positioning main body 1 is provided with a plurality of annular blade mounting grooves 2 for simultaneously mounting the multi-stage blades, so that the multi-stage rotor blades can be ground and processed conveniently. The weight-reducing cavity 3 is arranged in the positioning main body 1 to reduce the weight of the whole grinding tool, so that the whole grinding tool can be applied to the existing grinding machine.

Specifically, because the number of the rotor blades of the air compressor is large, and the overall diameter of each stage of blades is large, if the positioning main body 1 is designed to be of a solid structure, the weight of the whole grinding tool is overweight, and the grinding machine is difficult to support.

Wherein, alternatively, the blade mounting slots 2 are two, three or more than four.

On the basis of any one of the above schemes, the positioning main body 1 comprises a plurality of positioning disks 4, each positioning disk 4 is provided with a blade mounting groove 2 on the outer wall, the positioning disks 4 are coaxial and are fixedly connected in sequence along the axial direction of the positioning disks, and the weight-reducing cavity 3 is formed inside the positioning disks 4.

The positioning disks 4 are respectively processed and then fixedly connected together, so that the processing difficulty is effectively reduced.

Alternatively, the plurality of positioning disks 4 are integrally formed.

On the basis of any one of the above schemes, the positioning disc 4 is annular, and an annular spoke disc 5 is also fixed on the inner wall of the positioning disc 4.

As shown in FIG. 1, the spoke plate 5 is arranged in the positioning plate 4, so that the thickness of the side wall of the tool is increased, and the structural strength of the tool is further enhanced.

Specifically, the spokes 5 of the plurality of positioning disks 4 are arranged at intervals.

On the basis of any one of the above schemes, a plurality of positioning disks 4 are welded in sequence.

On the basis of any one of the above schemes, the cross section of each blade mounting groove 2 is trapezoidal.

Specifically, as shown in fig. 4, the blade mounting groove 2 has a trapezoidal cross-sectional shape along the radial direction of the positioning body 1. That is, the blade mounting groove 2 is a dovetail groove, and the shape of the blade mounting groove 2 is adapted to the shape of the rotor blade root.

On the basis of any one of the above schemes, each of the blade mounting grooves 2 is provided with an insertion groove 6 along a radial direction thereof.

When the rotor blade is mounted or dismounted, the rotor blade is inserted into or taken out of the blade mounting slot 2 from the insertion slot 6.

In addition to any of the above, as shown in fig. 4, locking grooves 7 are provided on both sides of the insertion groove 6 in the circumferential direction of the blade mounting groove 2.

When the last rotor blades are installed, locking blocks are installed, and the locking blocks are clamped into the locking grooves 7 to circumferentially position all the rotor blades.

On the basis of any one of the above schemes, the rotor blade grinding tool further comprises a first shaft head 8 and a second shaft head 9, and the first shaft head 8 and the second shaft head 9 are respectively fixed at two ends of the positioning main body 1.

The rotor blade grinding tool is mounted to a grinding machine by means of a first stub shaft 8 and a second stub shaft 9.

In any of the above embodiments, the number of the blade mounting grooves 2 is seven.

Seven blade mounting slots 2 are correspondingly used for mounting 10-16 stage compressor rotor blades.

On the basis of any one of the above schemes, the material of the positioning body 1 is 45# steel.

The positioning main body 1 adopts 45# steel, the Rockwell hardness is 32-35HRC, the tensile strength after tempering heat treatment can reach 1059MPA, the unit price is within 10 yuan/KG, the cost is low, the welding performance is good, the reliable connection can be realized by general argon arc welding, the requirement on the skill level of personnel is relatively low, and the problems of oxidization, air holes, lack of penetration and the like are not easy to occur.

In one particular example, the process of assembling the rotor blade to the rotor blade grinding tool is specifically:

1) Rotor blades of corresponding stages are selected according to the stages of the blade mounting grooves 2 of the tool (each stage of rotor blades comprises a plurality of common blades 10, two first locking blades 11 and two second locking blades 12);

2) Inserting the common blades 10 into the blade mounting grooves 2 from the insertion grooves 6, sliding the common blades 10 into the blade mounting grooves 2 in the circumferential direction, and installing the balancing weights 14 between the two common blades 10 at the designed positions; mounting the blade and counterweight 14 until four blade positions remain;

3) As shown in fig. 4 and 5, the first locking blade 11 (having a locking groove for placing the locking piece 13 on the right side thereof) is fitted into the insertion groove 6 and slid toward the left locking groove 7. Ensuring that the locking groove notch on the edge plate of the first locking blade 11 faces the insertion groove 6;

4) The second locking blade 12 (which has a locking groove on the left side thereof for placing the locking piece 13) is fitted into the insertion groove 6 and slid toward the right side locking groove 7. Ensuring that the locking slot cut-outs on the rim plate of the second locking blade 12 face the insertion slot 6;

5) Two locking pieces 13 are mounted in the insertion slot 6 and slid so that each locking piece 13 rests against the mounted first locking blade 11 and second locking blade 12, respectively. Ensuring that the slope of the locking piece 13 coincides with the slope of the hub. At this time, the fixing screw of the locking piece should retract;

6) The other first locking blade 11 or the second locking blade 12 is installed. Ensuring that the locking groove notch of the blade edge plate faces the corresponding locking piece;

7) Moving the whole stage of rotor blades in the circumferential direction by a distance of about 50% of the blade edge plate width until it is sufficient to mount the last blade (second locking blade 12 or first locking blade 11); the last blade is installed. Ensuring that the locking groove notch of the blade edge plate faces the corresponding locking piece;

8) The full stage blade is moved in the opposite direction until the locking block is aligned with the locking slot in the hub.

9) The set screw of the locking block is tightened to raise one locking block into the locking groove of the hub. The set screw is tightened to a torque higher than the rotational torque. The top of the locking block should be flush or lower than the blade edge plate.

The design idea of the rotor blade grinding tool is as follows:

according to the scheme I, the two ends are designed to be dummy shafts, the middle section is shaped to be processed by the size of the 10-16-stage hub of the reverse compressor, and the whole inside is of a hollow structure. The advantage is simple structure, easy processing. The whole weight is 1100KG, the maximum bearing of the existing balancing machine is 1000KG, and the whole tool is overweight; the second disadvantage is that a set of matching tools is needed to be designed for the balanced and high-speed tip grinder. Through comprehensive analysis, scheme one is not feasible.

And in a second scheme, the whole compressor rotor is simulated, wherein the whole compressor rotor comprises 0-16 stages, wherein 0-9 stages adopt dummy shafts, and structures such as front and rear shaft diameters, splines, threads and the like are reserved. The tool has the advantages that the whole tool completely simulates the rotor, the accuracy and the reliability of the tool can be guaranteed to the greatest extent, the original tool and the original program can be adopted for balancing, hoisting and grinding the high-speed tip grinding machine, and the matching cost is reduced. The defect is that the whole rotor is 2.2 m long, the length is too long, the machining difficulty is increased, the coaxiality of the journals at two ends is difficult to control within 0.005mm, the tool is easy to flexibly deform on a high-speed blade tip mill, and the possibility of vibration is increased.

And in a third scheme (shown in fig. 1), the advantages and disadvantages of the first scheme and the second scheme are combined, the external dimension of the outer contour of the positioning main body 1 on the stage 10-16 of the reverse compressor rotor hub, the external dimension of the shaft diameters of the first shaft head 8 and the second shaft head 9 on the reverse compressor rotor hub, the external dimension of the spline, the external dimension of the screw thread and the like are combined. The 10-16 level is divided into 7 sections (each level is a section), each section is of a single-disc structure (namely a positioning disc 4), the 7-level positioning disc 4, the first shaft head 8 and the second shaft head 9 are fixed together in a welding mode after the inner spoke disc 5 is processed, so that the processing difficulty is effectively reduced, and the whole weight of the tool is reduced. Meanwhile, the thickness of the tool is increased, and the structural strength of the tool is further enhanced.

The technological route of the rotor blade grinding tool of the embodiment is as follows:

1) Part mapping: mapping the external dimensions of the 10-16-level compressor rotor hub by using three-dimensional scanning equipment, three coordinates and the like;

2) Selecting materials: analyzing the components of raw materials by using a metallographic analyzer, comparing the performances, and selecting a proper conventional metal material;

3) Designing and processing: drawing by utilizing software such as AUTOCAD;

4) And (3) processing and forming: machining and forming by using machining equipment, and eliminating machining stress by heat treatment;

5) And (3) product acceptance: and after processing, carrying out size and applicability acceptance.

The technical difficulties of the rotor blade grinding tool of this embodiment are analyzed as follows:

1) The precision is high. The blade mounting groove 2 is dovetail-shaped, conventional measurement is difficult to achieve, measurement accuracy needs to be controlled within 0.02mm, and coaxiality of the first shaft head 8 and the second shaft head 9 needs to be controlled within 0.005mm.

2) The requirement on the balance of the tool is high. The final unbalance is controlled in 635g.mm, otherwise the whole tool will vibrate in the rotation process, firstly the guide rail precision of the high-speed tip grinder will be damaged, and secondly the size deviation of the grinding blade will be caused.

3) The precision requirement of the machining forming is high, the roundness of each stage of blade mounting groove 2 is required to be 0.02mm, the coaxiality is 0.02mm, and the accumulated error is not more than 0.04mm. Otherwise, the blade and the tool are not matched when the high-speed blade tip grinding equipment works, and the grinding precision of the blade is affected.

4) The stability and the accuracy of the grinding tool are also related to various factors such as blade installation locking, tool weight, hoisting requirements and the like, and the grinding work can be ensured to be smoothly carried out only by comprehensively considering overall.

The process control of the rotor blade grinding tool of the embodiment:

1) And (5) precision control. Firstly, all critical position dimensions such as shaft diameter, positioning dimensions and the like on a design drawing are all aviation standards, and tolerance precision is accurate to a micron level. And secondly, a three-dimensional scanning device with the measurement precision of 0.008mm and a three-coordinate measuring device with the measurement precision of 0.002mm are adopted to reversely map and model the rotor of the air compressor, so that the measurement precision is controllable. And thirdly, a three-dimensional scanning device with the measurement precision of 0.008mm is adopted to carry out optical scanning to replace a traditional sample plate gauge with the precision of 0.05mm to finish the measurement of the distance and angle between the inner arcs of the blade mounting groove 2 grooves in the lathe machining process, and the machining process is carried out while the measurement is carried out in the finish machining process, so that the machining precision is effectively ensured. And fourthly, a threaded connection structure of the compressor rotor is replaced by a segmented welding mode, so that the coaxiality and the machining precision of the tool are further improved. Fifthly, the machining mode of the first shaft head 8 and the second shaft head 9 is completed by one-time clamping of a large machine tool in the finish machining process, and coaxiality is effectively guaranteed to be controlled within 0.005mm.

2) And controlling unbalance amount. The method comprises the steps of segmented rough machining, combined welding forming, heat treatment and semi-finishing, so that the uniformity of the tool is guaranteed. The end surfaces of the two sides of the tooling are respectively provided with 12 weight ports for adjusting unbalance, and the unbalance is effectively controlled at 225g.mm and is lower than 635g.mm required by an OEM manual.

3) And (5) structural strength accounting. Through finite element analysis, the frock is under the operating mode of 1750rpm, fully loads 522 blades, and its frock everywhere yield strength reserve coefficient is greater than 1, and radial deformation is less than 0.013mm, does not have the fracture risk.

The multistage hub type rotor blade grinding tool needs to be verified after machining, and the contents comprise blade installation clearance, weight, front shaft diameter coaxiality, machining precision of the blade installation groove 2 and the like. Firstly, the axial clearance of the blades in the blade mounting groove 2 is measured to be in the range of 0.3-0.5mm, and the radial clearance is measured to be in the range of 0.1-0.3mm, so that the axial clearance is consistent with the installation of the blades on the compressor rotor. And secondly, the weight of the tool is measured to be 470KG, so that the design requirement is met. And thirdly, the tool is installed on a high-speed blade tip grinding machine, and the coaxiality measured value of the first shaft head 8 and the second shaft head 9 is 0.001mm and is lower than 0.005mm required by design. And fourthly, 3 gas turbine compressor rotor blades are respectively installed on the tool and the compressor rotor for comparison and verification, the blade length detection tool is used for single-chip size measurement, the size deviation is smaller than 0.04mm, and the 10-16-level machining precision of the multistage shaft hub type grinding tool meets the design requirement.

In the description of the present utility model, it should be noted that the azimuth or positional relationship indicated by the terms "axial", "radial", "circumferential", etc. are based on the azimuth or positional relationship shown in the drawings, and are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or element in question must have a specific azimuth, be configured and operated in a specific azimuth, and thus should not be construed as limiting the present utility model.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present utility model, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The foregoing description of the preferred embodiments of the utility model is not intended to limit the utility model to the precise form disclosed, and any such modifications, equivalents, and alternatives falling within the spirit and scope of the utility model are intended to be included within the scope of the utility model.

Claims (10)

1. The utility model provides a rotor blade grinding frock, its characterized in that, includes location main part (1), location main part (1) lateral wall has a plurality of annular blade mounting groove (2), a plurality of blade mounting groove (2) coaxial and follow the axial interval setting of location main part (1), the inside lightening chamber (3) that has of location main part (1).

2. A rotor blade grinding tool according to claim 1, wherein the positioning body (1) comprises a plurality of positioning discs (4), each positioning disc (4) is provided with a blade mounting groove (2) on the outer wall, the positioning discs (4) are coaxial and are fixedly connected in sequence along the axial direction of the positioning discs, and the weight-reducing cavity (3) is formed inside the positioning discs (4).

3. A rotor blade grinding tool according to claim 2, characterized in that the positioning disc (4) is annular, and the inner wall of the positioning disc (4) is further fixed with an annular spoke disc (5).

4. A rotor blade grinding tool according to claim 2, characterized in that a plurality of said positioning discs (4) are welded in sequence.

5. A rotor blade grinding tool according to claim 1, characterized in that each blade mounting groove (2) has a trapezoidal cross section.

6. A rotor blade grinding tool according to claim 1, characterized in that each of the blade mounting slots (2) is provided with an insertion slot (6) along its radial direction.

7. A rotor blade grinding tool according to claim 6, characterized in that the insertion grooves (6) are provided with locking grooves (7) along both sides of the blade mounting groove (2) in the circumferential direction, respectively.

8. A rotor blade grinding tool according to any one of claims 1-7, further comprising a first stub shaft (8) and a second stub shaft (9), the first stub shaft (8) and the second stub shaft (9) being secured to respective ends of the positioning body (1).

9. A rotor blade grinding tool according to any of claims 1-7, characterized in that the number of blade mounting slots (2) is seven.

10. A rotor blade grinding tool according to any of claims 1-7, characterized in that the material of the positioning body (1) is 45# steel.