Blade test fixture

Abstract

A blade test clamp is used for simulating assembling and pre-twisting of a blade crown. A blade crown of the blade is provided with a first extrusion surface and a second extrusion surface; the blade test clamp comprises a blade root clamping assembly and a blade crown clamping assembly. The blade root clamping assembly is configured to fix the blade root of the blade; the blade crown clamping assembly comprises a first clamping jaw, a second clamping jaw groove and a second clamping jaw, the second clamping jaw groove is fixed relative to the first clamping jaw, the second clamping jaw groove and the first clamping jaw can be arranged in a synchronous rotating mode, the second clamping jaw is used for being connected with the second clamping jaw groove in an inserted mode so as to position and limit the first clamping jaw and the second clamping jaw at the clamping position, and the first clamping jaw and the second clamping jaw are clamped. The first clamping face of the first clamping jaw is configured to incline relative to the first extrusion face in the first rotating direction, and the second clamping face of the second clamping jaw is configured to incline relative to the second extrusion face in the first rotating direction, so that when the first clamping face abuts against the first extrusion face and the second clamping face abuts against the second extrusion face, the blade crown rotates in the first rotating direction.

Description

Technical Field

[0001] The invention relates to the field of aero-engine testing, and in particular to a blade testing fixture. Background Art

[0002] The blade crown of a turbine blade generally has two functions: one is to improve the performance of the turbine. The radial clearance of the turbine will change during operation. Whether it can work in the best position directly affects the performance of the turbine. In the absence of experience, in order to prevent mechanical wear in the transition state, the radial clearance is often selected to be too large, resulting in excessive radial leakage loss in the steady state. After the blade is set with a blade crown, the gap between the comb teeth on the blade crown and the outer ring of the honeycomb can be reduced, and the honeycomb can be allowed to wear, thereby reducing the leakage loss. The second is to change the vibration characteristics of the turbine blade. The adjacent blade crowns are in contact through the blade crown contact surface, which is equivalent to setting a fulcrum at the tip of the blade. By reasonably setting the assembly pre-tightening between the adjacent blade crown contact surfaces, the vibration characteristics of the blade during operation can be improved. It is very important to choose a reasonable assembly pre-tightening of the blade crown contact surface. If the assembly pre-tightening is too small, gaps will appear between the adjacent blade crown contact surfaces, which will not play the role of dry friction damping and vibration reduction. At the same time, it will also cause gas leakage losses. If the tightness is too large, the extrusion stress of the adjacent blade crown contact surfaces will be too large, which will affect the life of the blade. Therefore, in the design of blade shrouds, the key is to ensure that when the blades are working, the adjacent shroud contact surfaces always maintain a reasonable assembly pre-tightness, so as to improve the turbine efficiency and reduce vibration. Therefore, in the turbine blade shroud extrusion wear vibration fatigue test, it is necessary to simulate the assembly pre-tightness of the shroud through the fixture, and simulate the different assembly tightness of the shroud contact surface. Summary of the invention

[0003] The object of the present invention is to provide a blade test fixture for simulating the assembly pre-twist of a blade crown.

[0004] The blade crown of the blade has a first extrusion surface and a second extrusion surface. According to an embodiment of the present invention, the blade test fixture includes a blade root clamping assembly and a blade crown clamping assembly; the blade root clamping assembly is configured to fix the blade root of the blade; the blade crown clamping assembly includes a first clamping jaw, a second clamping jaw slot and a second clamping jaw, the second clamping jaw slot is fixed relative to the first clamping jaw, the second clamping jaw slot and the first clamping jaw can be synchronously rotatably arranged, the second clamping jaw is used to insert the second clamping jaw slot to position and limit the first clamping jaw and the second clamping jaw in a clamping position, in which the first clamping surface of the first clamping jaw is configured to be inclined relative to the first extrusion surface in a first rotation direction, and the second clamping surface of the second clamping jaw is configured to be inclined relative to the second extrusion surface in the first rotation direction, so that when the first clamping surface abuts the first extrusion surface and the second clamping surface abuts the second extrusion surface, the blade crown rotates in the first rotation direction.

[0005] In one or more embodiments, the shape and size of the second clamping jaw groove are the same as those of the second clamping jaw.

[0006] In one or more embodiments, the second clamping jaw groove and the first clamping jaw are arranged on a turntable, the turntable is rotatably arranged on the base body, and the second clamping jaw is used to be fixedly connected to the base body to limit the first clamping jaw and the second clamping jaw in the clamping position.

[0007] In one or more embodiments, the optical axis of the turntable is inserted into the optical hole of the base.

[0008] In one or more embodiments, the threaded hole of the second clamping jaw and the threaded hole of the seat body are threadedly connected with bolts, and the bolts press and fix the second clamping jaw to the seat body.

[0009] In one or more embodiments, the second jaw groove has a fan-shaped profile, and the second jaw has a fan-shaped profile.

[0010] In one or more embodiments, the first clamping surface is configured to be inclined at a first angle relative to the first extrusion surface in the first rotation direction, and the second clamping surface is configured to be inclined at the first angle relative to the second extrusion surface in the first rotation direction.

[0011] In one or more embodiments, the first clamping surface and the second clamping surface are parallel to each other.

[0012] In one or more embodiments, the first clamping surface and the second clamping surface are provided with gasket grooves, and the gasket grooves are provided with replaceable gaskets. The replaceable gaskets respectively protrude from the first clamping surface and the second clamping surface to respectively abut the first extrusion surface and the second extrusion surface. The replaceable gaskets include multiple groups, and the thickness of each group of replaceable gaskets protruding from the first clamping surface and the second clamping surface is different.

[0013] In one or more embodiments, the blade root clamping assembly comprises a tenon groove for accommodating a tenon of the blade root, and a bolt protrudes from a bottom of the tenon groove to push the tenon against the tenon groove.

[0014] The embodiments of the present invention have at least the following beneficial effects:

[0015] In the clamping position, the first clamping surface of the first clamping jaw is inclined toward the first rotation direction relative to the first extrusion surface of the untwisted blade crown, and the second clamping surface of the second clamping jaw is inclined toward the first rotation direction relative to the second extrusion surface of the untwisted blade crown. The first clamping surface abuts the first extrusion surface, and the blade crown tends to rotate toward the first rotation direction to reduce the gap. The second clamping surface abuts the second extrusion surface, and the blade crown tends to rotate toward the first rotation direction to reduce the gap, so that the blade crown is driven to rotate toward the first rotation direction, and the blade crown is twisted relative to the blade root, simulating the assembly pre-twist of the blade crown. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0017] Figure 1 This is an oblique view of the blade test fixture holding the blade;

[0018] Figure 2 A top view of a blade root clamping assembly clamping a blade root;

[0019] Figure 3 for Figure 2 A partial enlarged view of

[0020] Figure 4 is an oblique view of the seat body;

[0021] Figure 5 is an oblique view of the turntable, the first clamping jaw and the second clamping jaw slot;

[0022] Figure 6 is an oblique view of the second clamping jaw;

[0023] Figure 7 A front view of a blade crown clamping assembly clamping a blade crown;

[0024] Figure 8 The schematic diagram of the blade crown clamping assembly for clamping the blade crown to twist;

[0025] Fig. 9 Schematic diagram of the blade crown clamping assembly clamping the blade crown torsion.

[0026] Reference numerals:

[0027] 1-Blade root clamping assembly;

[0028] 2-leaf crown clamping assembly;

[0029] 3-leaf;

[0030] 4-leaf root;

[0031] 5-leaf crown;

[0032] 6- first seat body;

[0033] 7- first bolt;

[0034] 8-mortise and tenon;

[0035] 9-tenon;

[0036] 10- second bolt;

[0037] 11-tenon working surface;

[0038] 12-mortise and tenon working surface;

[0039] 13- first extrusion surface;

[0040] 14- second extrusion surface;

[0041] 15- first clamping jaw;

[0042] 16- second clamping jaw slot;

[0043] 17- second clamping jaw;

[0044] 18-Turntable;

[0045] 19- Second seat body;

[0046] 20-optical axis;

[0047] 21-light hole;

[0048] 22-turntable slot;

[0049] 23- first chamfered surface;

[0050] 24- second chamfered surface;

[0051] 25-third bolt;

[0052] 26- second threaded hole;

[0053] 27- third threaded hole;

[0054] 28- first clamping surface;

[0055] 29- second clamping surface;

[0056] 30- first rotation direction;

[0057] 31- fourth bolt;

[0058] 32-gasket groove;

[0059] 33-Replaceable gasket. DETAILED DESCRIPTION

[0060] Reference will now be made in detail to embodiments of the present invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided to explain the present invention, not to limit the present invention. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made in the present invention without departing from the scope or spirit of the present invention. For example, a feature illustrated or described as part of one embodiment may be used together with another embodiment to produce yet another embodiment. Therefore, the present invention is intended to cover these modifications and variations within the scope of the appended claims and their equivalents.

[0061] It should be noted that these and other subsequent drawings are only examples and are not drawn to scale, and should not be used to limit the actual scope of protection required by the present invention.

[0062] The terms "first", "second", etc. may be used interchangeably to distinguish one feature from another, and are not intended to mean that each feature must be located as shown in the figures in each embodiment.

[0063] like Figure 1 As shown, the blade test fixture includes a blade root clamping assembly 1 and a blade crown clamping assembly 2. The blade root clamping assembly 1 clamps the blade root 4 ( Figure 2 and Figure 3 The blade crown clamping assembly 2 clamps the blade crown 5 of the fixed blade 3.

[0064] like Figures 1 to 3 As shown, the blade root clamping assembly 1 may be provided with a first seat body 6. The first seat body 6 may be fixed to a test bench, such as a vibration bench for a vibration fatigue test, by a first bolt 7. The first seat body 6 may be provided with a tenon groove 8, and the tenon groove 8 accommodates the tenon 9 of the blade root 4, and the tenon 9 is located in the tenon groove 8. The first seat body 6 may be provided with a first threaded hole at the bottom of the tenon groove 8, and a second bolt 10 may be threadedly connected to the first threaded hole. The screw of the second bolt 10 protrudes from the bottom of the tenon groove 8 into the tenon groove 8, and the screw of the second bolt 10 pushes the bottom surface of the tenon 9, so that the tenon 9 is attached to the tenon groove 8, and the tenon working surface 11 is attached to the tenon groove working surface 12, and the tenon 9 is completely clamped and fixed.

[0065] like Figure 7 As shown, the blade crown 5 has a first extrusion surface 13 and a second extrusion surface 14, which are respectively located at two circumferential edges of the blade crown 5, and are used to contact, press and rub against the extrusion surfaces of the circumferentially adjacent blade crowns. The blade crown 5 can be a sawtooth blade crown, and the first extrusion surface 13 and the second extrusion surface 14 are provided by the short edges of the saw teeth located at the circumferential edge.

[0066] like Figures 5 to 7 As shown, the blade crown clamping assembly 2 includes a first clamping jaw 15, a second clamping jaw slot 16 and a second clamping jaw 17. Figure 5 As shown, the second clamping jaw groove 16 is fixed relative to the first clamping jaw 15, and the second clamping jaw groove 16 and the first clamping jaw 15 can be synchronously rotated. The second clamping jaw groove 16 and the first clamping jaw 15 can be set on a rotating disk 18, the first clamping jaw 15 protrudes from the disk surface of the rotating disk 18, and the second clamping jaw groove 16 is recessed from the disk surface of the rotating disk 18. The rotating disk 18 is rotatably set on Figure 4 The second seat body 19 and the turntable 18 shown in the figure can be provided with an optical axis 20, and further combined with Figure 4 The second seat body 19 may be provided with a light hole 21, and the optical axis 20 is inserted into the light hole 21 and can slide and rotate relative to the light hole 21. The second seat body 19 may also be provided with a turntable groove 22, and the turntable 18 rotates in the turntable groove 22.

[0067] like Figures 5 to 7 As shown, the second clamping jaw 17 is used to be inserted into the second clamping jaw slot 16 to position and limit the first clamping jaw 15 and the second clamping jaw 17 in the clamping position. The shape and size of the second clamping jaw slot 16 can be the same as those of the second clamping jaw 17. When the second clamping jaw 17 is inserted into the second clamping jaw slot 16, the turntable 18 rotates to fully align the second clamping jaw slot 16 with the second clamping jaw 17, thereby positioning the first clamping jaw 15 and the second clamping jaw 17 in the clamping position. The second clamping jaw slot 16 can have a fan-shaped profile, and the second clamping jaw 17 can have a fan-shaped profile. When the second clamping jaw 17 is inserted into the second clamping jaw slot 16, the two straight side walls of the second clamping jaw 17 push the two straight side walls of the second clamping jaw slot 16, and the two straight side walls of the second clamping jaw 17 slide relative to the two straight side walls of the second clamping jaw slot 16, so that the second clamping jaw slot 16 and the second clamping jaw 17 are aligned and inserted.

[0068] like Figure 5 and Figure 6 As shown, the second clamping jaw groove 16 can be provided with a first chamfered surface 23 at the outer edge of the bottom wall, and the second clamping jaw 17 can be provided with a second chamfered surface 24 at the root of the bottom wall to reduce stress concentration. The second clamping jaw 17 is inserted into the second clamping jaw groove 16, and the second chamfered surface 24 is attached to the first chamfered surface 23, which further positions the second clamping jaw 17 to be completely aligned with the second clamping jaw groove 16, thereby positioning the first clamping jaw 15 and the second clamping jaw 17 in the clamping position.

[0069] like Figure 7 As shown, in the clamping position, the second clamping jaw 17 can be fixedly connected to the second seat body 19, the second clamping jaw 17 is limited, the second clamping jaw 17 is inserted into the second clamping jaw slot 16 to limit the position of the rotating disk 18, and the first clamping jaw 15 is limited, so that the first clamping jaw 15 and the second clamping jaw 17 are limited in the clamping position. The second clamping jaw 17 can be fixed to the second seat body 19 by a third bolt 25, and the third bolt 25 is threadedly connected to the second threaded hole 26 ( Figure 6 ), the third threaded hole 27 of the second seat body 19 ( Figure 4), the second clamping jaw 17 is pressed and fixed to the second seat body 19. After removing the third bolt 25, the second clamping jaw 17 and the rotating disk 18 can be removed from the second seat body 19. Figure 1 As shown, the second base body 19 can be fixed to a test bench, such as a vibration table for a vibration fatigue test, by a fourth bolt 31 .

[0070] Figure 8 and Fig. 9 The principle of the blade crown clamping assembly 2 clamping the blade crown 5 for twisting is shown, wherein the first clamping jaw 15, the second clamping jaw 17 and the blade crown 5 are shown in a simplified manner. Figure 8 In the figure, the first clamping jaw 15 and the second clamping jaw 17 are located in the clamping position, the blade crown 5 is located in the untwisted position, the second clamping jaw 17 partially overlaps with the blade crown 5, and the outline of the overlapping portion is shown by a dotted line. Fig. 9 In the embodiment, the first clamping jaw 15 and the second clamping jaw 17 are located in the clamping position, and the blade crown 5 is located in the twisted position after twisting.

[0071] like Figure 8 As shown, in the clamping position, the first clamping surface 28 of the first clamping jaw 15 is inclined at a first angle to the first rotation direction 30 relative to the first extrusion surface 13 of the untwisted blade crown 5, and the second clamping surface 29 of the second clamping jaw 17 is inclined at a second angle to the first rotation direction 30 relative to the second extrusion surface 14 of the untwisted blade crown 5. Fig. 9 In the process of the second clamping jaw 17 being inserted into the second clamping jaw groove 16 and thus clamping the leaf crown 5 with the first clamping jaw 15, the first clamping surface 28 abuts against the first extrusion surface 13, and the leaf crown 5 tends to rotate in the first rotation direction 30 to reduce the interval of the first angle, and the second clamping surface 29 abuts against the second extrusion surface 14, and the leaf crown 5 tends to rotate in the first rotation direction 30 to reduce the interval of the second angle, so that the leaf crown 5 is driven to rotate in the first rotation direction 30, and the leaf crown 5 is twisted relative to the blade root 4, simulating the assembly pre-twist of the leaf crown 5. Compared with the leaf crown fixture that is first clamped and then rotated for loading, it is closer to the assembly pre-twist state of the leaf crown 5, has better simulation, and improves the accuracy of the test results.

[0072] like Figure 8 As shown, in the clamping position, the first angle at which the first clamping surface 28 is inclined relative to the first extrusion surface 13 in the first rotation direction 30 may be the same as the second angle at which the second clamping surface 29 is inclined relative to the second extrusion surface 14 in the first rotation direction 30, and the second clamping surface 29 is also inclined relative to the second extrusion surface 14 in the first rotation direction 30 at the first angle. Fig. 9In the process of the second clamping jaw 17 being inserted into the second clamping jaw groove 16 and thus clamping the leaf crown 5 with the first clamping jaw 15, the leaf crown 5 is driven to rotate in the first rotation direction 30. After the leaf crown 5 rotates by the first angle, the first extrusion surface 13 is attached to the first clamping surface 28, and the second extrusion surface 14 is attached to the second clamping surface 29. The leaf crown 5 stops rotating and is attached to the first clamping jaw 15 and the second clamping jaw 17, and is firmly clamped by the first clamping jaw 15 and the second clamping jaw 17.

[0073] like Figures 7 to 9 As shown, the first extrusion surface 13 and the second extrusion surface 14 can be parallel to each other, the first clamping surface 28 and the second clamping surface 29 can be inclined at the same angle relative to the first extrusion surface 13 and the second extrusion surface 14 toward the first rotation direction 30, and the first clamping surface 28 and the second clamping surface 29 can be parallel to each other.

[0074] The process of the above-mentioned leaf crown clamping assembly 2 clamping the leaf crown 5 is as follows: the first clamping surface 28 of the first clamping jaw 15 overlaps the first extrusion surface 13 of the leaf crown 5, and the second clamping jaw 17 is inserted into the second clamping jaw groove 16. As the second clamping jaw 17 is inserted, the turntable 18 and the first clamping jaw 15 thereon rotate, and the second clamping surface 29 of the second clamping jaw 17 abuts against the second extrusion surface 14 of the leaf crown 5, and the leaf crown 5 is driven to rotate in the first rotation direction 30. Finally, the first clamping jaw 15 on the turntable 18 rotates to the clamping position, and the second clamping jaw 17 is inserted into the second clamping jaw groove 16 at the clamping position, the first extrusion surface 13 is attached to the first clamping surface 28, and the second extrusion surface 14 is attached to the second clamping surface 29, and the leaf crown clamping assembly 2 clamps the leaf crown 5.

[0075] like Figure 5 and Figure 6As shown, the first clamping surface 28 and the second clamping surface 29 may be provided with a gasket groove 32. The gasket groove 32 may extend transversely from the ends of the first clamping jaw 15 and the second clamping jaw 17 to the first clamping surface 28 and the second clamping surface 29, respectively. The gasket groove 32 is provided with a replaceable gasket 33, and the replaceable gasket 33 may be inserted into the gasket groove 32 along the arrow direction shown in the figure. The replaceable gasket 33 protrudes from the gasket groove 32 to the first clamping surface 28 and the second clamping surface 29. When the blade crown clamping assembly 2 clamps the blade crown 5, the replaceable gasket 33 of the first clamping jaw 15 abuts against the first extrusion surface 13, and the replaceable gasket 33 of the second clamping jaw 17 abuts against the second extrusion surface 14. The replaceable gasket 33 applies an extrusion force to the first extrusion surface 13 and the second extrusion surface 14 to simulate the assembly tightness of the blade crown 5. The replaceable gaskets 33 include multiple groups, each group of replaceable gaskets 33 has a different thickness, and the thickness of each group of replaceable gaskets 33 protruding from the first clamping surface 13 and the second clamping surface 14 is different. The extrusion force applied by each group of replaceable gaskets 33 to the first extrusion surface 13 and the second extrusion surface 14 is different. By replacing different groups of replaceable gaskets 33, different assembly tightness of the leaf crown 5 can be simulated, and only different groups of replaceable gaskets 33 need to be replaced, and there is no need to disassemble the leaf crown clamping assembly 2, which is simple and convenient to operate.

[0076] The first base body 6, the second base body 19, the second clamping jaw 17, the rotating disk 18 and the first clamping jaw 15 thereon are all made of metal material, and may be made of stainless steel.

[0077] Although the present invention is disclosed as above by the embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention.

Claims

1. A blade test fixture, wherein the blade crown of the blade has a first extrusion surface and a second extrusion surface, characterized in that: The blade test fixture comprises: a blade root clamping assembly configured to fix the blade root of the blade; and The blade crown clamping assembly includes a first clamping jaw, a second clamping jaw slot and a second clamping jaw, wherein the second clamping jaw slot is fixed relative to the first clamping jaw, the second clamping jaw slot and the first clamping jaw can be synchronously rotatably arranged, and the second clamping jaw is used to insert into the second clamping jaw slot to position and limit the first clamping jaw and the second clamping jaw in a clamping position, in which the first clamping surface of the first clamping jaw is configured to be inclined relative to the first extrusion surface in a first rotation direction, and the second clamping surface of the second clamping jaw is configured to be inclined relative to the second extrusion surface in the first rotation direction, so that when the first clamping surface abuts the first extrusion surface and the second clamping surface abuts the second extrusion surface, the blade crown rotates in the first rotation direction.

2. The blade test fixture according to claim 1, characterized in that: The shape and size of the second clamping jaw groove are the same as those of the second clamping jaw.

3. The blade test fixture according to claim 2, characterized in that: The second clamping jaw groove and the first clamping jaw are arranged on a rotating disk, the rotating disk is rotatably arranged on a base body, and the second clamping jaw is used to be fixedly connected to the base body to limit the first clamping jaw and the second clamping jaw in the clamping position.

4. The blade test fixture according to claim 3, characterized in that: The optical axis of the rotating disk is inserted into the optical hole of the seat body.

5. The blade test fixture according to claim 3, characterized in that: The threaded hole of the second clamping jaw and the threaded hole of the seat body are threadedly connected with bolts, and the bolts press and fix the second clamping jaw to the seat body.

6. The blade test fixture according to claim 2, characterized in that: The second clamping jaw groove has a fan-shaped profile, and the second clamping jaw has a fan-shaped profile.

7. The blade test fixture according to claim 1, characterized in that: The first clamping surface is configured to be inclined at a first angle relative to the first extrusion surface in the first rotation direction, and the second clamping surface is configured to be inclined at the first angle relative to the second extrusion surface in the first rotation direction.

8. The blade test fixture according to claim 7, characterized in that: The first clamping surface and the second clamping surface are parallel to each other.

9. The blade test fixture according to claim 1, characterized in that: The first clamping surface and the second clamping surface are provided with gasket grooves, and the gasket grooves are provided with replaceable gaskets. The replaceable gaskets respectively protrude from the first clamping surface and the second clamping surface to respectively abut the first extrusion surface and the second extrusion surface. The replaceable gaskets include multiple groups, and the thickness of each group of replaceable gaskets protruding from the first clamping surface and the second clamping surface is different.

10. The blade test fixture according to claim 1, characterized in that: The blade root clamping assembly comprises a tenon groove, which is used to accommodate the tenon of the blade root. A bolt protrudes from the bottom of the tenon groove to push the tenon against the tenon groove.

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