Clamping device for machining large blade with thermal power bent blade root

Abstract

The invention discloses a clamping device for machining a thermal power bent blade root large blade, relates to the technical field of large blade clamping, and aims to solve the problem that an existing turbine blade clamping device can only clamp a straight blade root blade and cannot clamp a bent blade root blade. The ejector pin clamping mechanisms are fixed to the upper end face of the clamping disc, and every two adjacent ejector pin clamping mechanisms are arranged in an inclined mode. The ejector pin clamping mechanism comprises a sliding rail, a center table, an ejector pin, a clamping jaw, a two-way screw and a limiting boss. A center table is arranged in the center of the sliding rail, an ejector pin is installed at the upper end of the center table, two clamping jaws are connected to the sliding rail in a sliding mode, the two-way screw penetrates through the center table, threads on the two sides of the two-way screw are in threaded connection with the two clamping jaws respectively, and a limiting boss is arranged at the upper end of the sliding rail.

Description

Technical Field

[0001] The invention relates to the technical field of large blade clamping, and in particular to a clamping device for processing large blades with curved blade roots of thermal power plants. Background Art

[0002] Steam turbine blades are key components in steam turbines, and are mainly used to convert the thermal energy of steam into mechanical energy. They are installed on the rotor, and when steam passes through the blades, it drives the rotor to rotate, thereby driving the generator or other equipment. The processing accuracy of steam turbine blades is very high. In order to meet production requirements, special fixtures are needed to support production and processing. Casting square boxes is one of the commonly used methods. The casting square box uses Babbitt alloy, and a square fixing part is cast in the middle of the blade to facilitate the processing of the blade root. However, the casting square box method is cumbersome to operate. After casting the square box, the root tooth shape needs to be processed, and the airway needs to be processed after the square box is disassembled. Therefore, ejector fixtures are often used to fix the blades.

[0003] The utility model patent with publication number CN202212779U introduces a mechanical centering clamping blade fixture, which is provided with a reference top for supporting the blade positioning hole, and two clamping blocks that can move centripetally and clamp the blade process table. When clamping, the reference top is supported against the blade positioning hole, and the clamping blocks are tightened, so that the blade process table is clamped between the clamping blocks to complete the clamping of the blade. In the process of processing the root tooth shape, the fixing method of casting a square box with babbitt alloy is eliminated, and the fixing process of box casting and box disassembly is saved. The airway, root tooth shape and other processing surfaces of the turbine blade can be processed by the same machine tool, saving processing time and the use of babbitt alloy.

[0004] Steam turbine blades can be divided into straight blade root blades and curved blade root blades according to the shape of the blade root. However, the above clamping device can only clamp straight blade root blades, and cannot achieve a stable clamping effect for curved blade root blades. Summary of the invention

[0005] In order to solve the problem that the existing turbine blade clamping device can only clamp straight blade root blades but cannot clamp curved blade root blades, the present invention further provides a clamping device for processing large blades with curved blade roots of thermal power plants to solve the problems raised in the above background technology.

[0006] The technical solution of the present invention is:

[0007] A clamping device for processing large blades with curved blade roots of thermal power plants, comprising a clamping plate and a plurality of ejector clamping mechanisms, wherein the ejector clamping mechanisms are fixed to the upper end surface of the clamping plate, and adjacent ejector clamping mechanisms are arranged in an inclined shape;

[0008] The ejector clamping mechanism comprises a slide rail, a center platform, an ejector, a clamping claw, a bidirectional screw and a limiting boss; a center platform is arranged at the center of the slide rail, an ejector is installed at the upper end of the center platform, two clamping claws are slidably connected to the slide rail, the bidirectional screw passes through the center platform, the threads on both sides of the bidirectional screw are respectively threadedly connected with the two clamping claws, and a limiting boss is arranged at the upper end of the slide rail;

[0009] Furthermore, a convex groove is provided on the slide rail, and a convex slider is provided at the lower end of the clamping jaw, and the convex slider is slidably connected to the convex groove provided on the slide rail.

[0010] Furthermore, there are two ejector pin clamping mechanisms, and the slide rails are fixed on the clamping plate by welding.

[0011] Furthermore, the included angle between adjacent ejector pin clamping mechanisms is 15°-30°.

[0012] Furthermore, the clamping surface of the clamping jaw is provided with toothed clamp teeth.

[0013] Furthermore, the teeth of the toothed clamp are detachably connected to the clamping jaws via bolts.

[0014] Furthermore, both ends of the bidirectional screw are provided with hexagonal holes.

[0015] Furthermore, the ejector pin is fixed on the center platform by welding.

[0016] Furthermore, the ejector pin is made of chrome-vanadium steel.

[0017] Furthermore, the clamping disc is provided with a plurality of clamping disc fixing grooves in the circumferential direction.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. A clamping device for processing large blades with curved blade roots for thermal power plants, which is used for clamping the curved blade root end of the blade. Two ejector clamping mechanisms are provided. Two positioning holes are opened at the blade root. The ejector pins in the ejector clamping mechanism are inserted into the positioning holes on the blade root. The blade crown is fixed by a single ejector clamping mechanism, thereby realizing the clamping of the curved blade root.

[0020] 2. This clamping device fixes the curved blade root through double pins, and can fix the curved blade roots of blades of different sizes. By setting a bidirectional screw and two clamping claws, tighten the bidirectional screw to make the two clamping claws close to each other, fix the side wall of the curved blade root, and prevent the blade root from falling out of the pin. Because the blade root adopts two-point positioning clamping, for the curved blade roots of blades of different sizes, only two equidistant positioning holes need to be opened on the blade root, and the curved blade roots of blades of different sizes can be fixed. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the clamping device;

[0022] Figure 2 is a top view of the clamping device;

[0023] Figure 3 It is a structural schematic diagram of the ejector clamping mechanism;

[0024] Figure 4 This is the front view of the ejector clamping mechanism;

[0025] Figure 5 This is the exploded view of the ejector clamping mechanism;

[0026] Figure 6 It is a longitudinal cross-sectional view of the ejector clamping mechanism;

[0027] Figure 7 It is a side view of the ejector clamping mechanism;

[0028] Figure 8 Schematic diagram of the structure of the clamp.

[0029] In the figure: 1. chuck; 201. slide rail; 202. center table; 203. ejector pin; 301. clamping claw; 4. bidirectional screw; 204. limit boss; 205. embossed groove; 302. embossed slider; 5. toothed fixture tooth; 6. hexagonal hole; 7. chuck fixing groove. DETAILED DESCRIPTION

[0030] Specific implementation method 1: See Figure 3-7 As shown, a clamping device for processing large blades with curved blade roots of thermal power plants, this embodiment comprises a clamping plate 1 and a plurality of ejector clamping mechanisms, the ejector clamping mechanisms are fixed to the upper end surface of the clamping plate 1, and adjacent ejector clamping mechanisms are arranged in an inclined shape;

[0031] The ejector clamping mechanism includes a slide rail 201, a center platform 202, an ejector 203, a clamping jaw 301, a bidirectional screw 4 and a limiting boss 204; a center platform 202 is arranged at the center of the slide rail 201, an ejector 203 is installed at the upper end of the center platform 202, two clamping jaws 301 are slidably connected to the slide rail 201, the bidirectional screw 4 passes through the center platform 202, and the threads on both sides of the bidirectional screw 4 are respectively threadedly connected to the two clamping jaws 301, and a limiting boss 204 is arranged at the upper end of the slide rail 201.

[0032] Furthermore, the slide rail 201 is an integral structure, the center platform 202 is fixed to the center of the slide rail 201 by welding, a circular hole is provided on the center platform 202, and the bidirectional screw 4 passes through the circular hole and the center platform 202, so that the bidirectional screw 4 can rotate in the center platform 202, and the bidirectional screw 4 can slide left and right relative to the center platform 202, so that the two clamping jaws 301 can slide synchronously to the left or right relative to the center platform 202. The two clamping jaws 301 are symmetrically arranged relative to the center platform 202, and the two clamping jaws 301 are provided with screw holes that penetrate through them. With the center platform 202 as a reference, the screw holes provided on the left and right clamping jaws 301 have opposite rotation directions. The threads on both sides of the bidirectional screw 4 are respectively threadedly connected with the screw holes on the two clamping jaws 301. When the bidirectional screw 4 is rotated, the two clamping jaws 301 can move closer to or farther from each other. When the bidirectional screw 4 is rotated clockwise, the two clamping jaws 301 move closer to each other to clamp the curved blade root of the blade. When the bidirectional screw 4 is rotated counterclockwise, the two clamping jaws 301 move away from each other to release the curved blade root of the blade. The ejector pin 203 is fixed to the center of the upper end of the center platform 202 by embedding or welding. As a replaceable embodiment, the ejector pin 203 is integrally formed with the center platform 202. The limiting boss 204 is used to limit the position of the clamping jaws 301.

[0033] As an alternative embodiment, the middle section of the bidirectional screw 4 is provided with a shoulder and a retaining spring, which respectively abut the left and right sides of the center table 202, so that the bidirectional screw 4 cannot slide relative to the center table 202 along its own circumferential direction, forming a self-centering fixture. The bidirectional screw 4 can only rotate in the center table 202, and the two clamping jaws 301 are arranged equidistantly relative to the center table 202. When the bidirectional screw 4 is rotated, the two clamping jaws 301 are equidistantly closer to and farther from the center table 202.

[0034] Specific implementation method 2: See Figure 3-7 As shown, the slide rail 201 of this embodiment is provided with a convex groove 205 , and a convex slider 302 is provided at the lower end of the clamping jaw 301 , and the convex slider 302 is slidably connected in the convex groove 205 provided on the slide rail 201 .

[0035] Furthermore, the convex groove 205 in the slide rail 201 and the convex slider 302 provided at the lower end of the clamp 301 are completed by milling. The lower end of the center table 202 has the same structure as the convex slider 302. The center table 202 is fixed by welding after sliding into the slide rail 201. The slide rail 201 and the center table 202 are separately processed and formed, which is convenient for processing the convex groove 205 in the slide rail 201. The shape of the convex groove 205 and the convex slider 302 is similar to a convex character. The bidirectional screw 4 is located in the convex groove 205 in the slide rail 201, and the screw hole on the clamp 301 is opened on the convex slider 302.

[0036] The clamping device fixes the curved blade root through a double pin, two positioning holes are opened on the blade root, the pin 203 in the pin clamping mechanism is inserted into the positioning hole on the blade root, the bidirectional screw 301 is tightened to make the two clamping jaws 301 close to each other, and the clamping jaws 301 fix the side wall of the curved blade root to prevent the blade root from falling out of the pin. Because the blade root adopts two-point positioning clamping, for the curved blade roots of different sizes, only two equidistant positioning holes need to be opened on the blade root, so that the blade roots of different sizes can be fixed.

[0037] Specific implementation method three: see Figure 1-2 As shown, the ejector pin clamping mechanism of this embodiment is two, and the slide rail 201 is fixed on the clamping plate 1 by welding.

[0038] Specific implementation method four: see Figure 1-2 As shown, the included angle between adjacent ejector pin clamping mechanisms in this embodiment is 15°-30°.

[0039] Further, the slide rail 201 is fixed on the clamping plate 1 by welding. As an alternative embodiment, a screw hole is provided at the lower end of the slide rail 201, and the bolt passes through the clamping plate 1 to fix the slide rail 201 on the clamping plate 1. The axes of the bidirectional screws 4 in the two ejector clamping mechanisms are 15°-30° relative to each other, and the ejectors 203 in the two ejector clamping mechanisms are on the same arc relative to the center of the circle.

[0040] Specific implementation method five: see Figure 8 As shown, the clamping surface of the clamping jaw 301 of this embodiment is equipped with a toothed clamp tooth 5.

[0041] Specific implementation method six: see Figure 8 As shown, the toothed clamp teeth 5 of this embodiment are detachably connected to the clamping jaw 301 via bolts.

[0042] Furthermore, the tooth surface of the toothed clamp teeth 5 protrudes from the end surface of the clamping jaw 301, and the toothed clamp teeth 5 is used to increase the friction between the blade root and the toothed clamp teeth 5. A through hole is provided on the toothed clamp teeth 5, and a threaded hole is provided on the clamping jaw 301. The bolt passes through the toothed clamp teeth 5 and is threadedly connected to the clamping jaw 301, so that the toothed clamp teeth 5 and the clamping jaw 301 are detachably fixed.

[0043] Specific implementation method seven: See Figure 7 As shown, both ends of the bidirectional screw 4 of this embodiment are provided with hexagonal holes 6.

[0044] Furthermore, a hexagonal hole 6 is provided to facilitate the rotation of the bidirectional screw 4 during operation.

[0045] Specific implementation method eight: See Figure 3As shown, the ejector pin 203 of this embodiment is fixed on the center platform 202 by welding.

[0046] Specific implementation method nine: See Figure 3 As shown, the ejector pin 203 of this embodiment is made of chrome vanadium steel.

[0047] Furthermore, the ejector pin 203 is made of chrome-vanadium steel, which can reduce the wear of the ejector pin 203 .

[0048] Specific implementation method ten: See Figure 1-2 As shown, the clamping plate 1 of this embodiment is provided with a plurality of clamping plate fixing grooves 7 in the circumferential direction.

[0049] Furthermore, the clamping plate fixing groove 7 is used for fixed connection with a work surface or a machine tool spindle.

[0050] When in use, two positioning holes are opened at the curved root of the blade, the ejector pin 203 in the ejector pin clamping mechanism is inserted into the positioning hole on the blade root, and the blade crown is fixed by the single ejector pin clamping mechanism, thereby realizing the clamping of the curved root of the blade.

[0051] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A clamping device for processing large blades with curved blade roots for thermal power generation, characterized in that: It comprises a clamping disc (1) and a plurality of ejector clamping mechanisms, wherein the ejector clamping mechanisms are fixed to the upper end surface of the clamping disc (1), and adjacent ejector clamping mechanisms are arranged in an inclined shape; The ejector clamping mechanism comprises a slide rail (201), a center platform (202), an ejector pin (203), a clamping claw (301), a bidirectional screw rod (4) and a limiting boss (204); a center platform (202) is arranged at the center of the slide rail (201), an ejector pin (203) is installed at the upper end of the center platform (202), two clamping claws (301) are slidably connected to the slide rail (201), the bidirectional screw rod (4) passes through the center platform (202), threads on both sides of the bidirectional screw rod (4) are respectively threadedly connected to the two clamping claws (301), and a limiting boss (204) is arranged at the upper end of the slide rail (201).

2. The clamping device for machining large blades with curved blade roots for thermal power plants according to claim 1 is characterized in that: The slide rail (201) is provided with a convex groove (205), and the lower end of the clamping jaw (301) is provided with a convex slider (302), which is slidably connected to the convex groove (205) provided on the slide rail (201).

3. The clamping device for machining large blades with curved blade roots for thermal power plants according to claim 1 is characterized in that: There are two ejector pin clamping mechanisms, and the slide rail (201) is fixed on the clamping plate (1) by welding.

4. The clamping device for machining large blades with curved blade roots for thermal power plants according to claim 1 is characterized in that: The included angle between adjacent ejector pin clamping mechanisms is 15°-30°.

5. The clamping device for machining large blades with curved blade roots for thermal power plants according to claim 1 is characterized in that: The clamping surface of the clamping jaw (301) is provided with toothed clamp teeth (5).

6. The clamping device for machining large blades with curved blade roots for thermal power plants according to claim 5 is characterized in that: The toothed clamp teeth (5) are detachably connected to the clamping jaw (301) via bolts.

7. The clamping device for machining large blades with curved blade roots for thermal power plants according to claim 1 is characterized by: Both ends of the bidirectional screw (4) are provided with hexagonal holes (6).

8. The clamping device for machining large blades with curved blade roots for thermal power plants according to claim 1 is characterized in that: The ejector pin (203) is fixed on the center platform (202) by welding.

9. The clamping device for machining large blades with curved blade roots for thermal power plants according to claim 1, characterized in that: The ejector pin (203) is made of chrome-vanadium steel.

10. The clamping device for machining large blades with curved blade roots for thermal power plants according to claim 1, characterized in that: The clamping disc (1) is provided with a plurality of clamping disc fixing grooves (7) in the circumferential direction.

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