WO2019039690A1

WO2019039690A1 - Apparatus for testing creep of turbine blade

Info

Publication number: WO2019039690A1
Application number: PCT/KR2018/003626
Authority: WO
Inventors: 박훤
Original assignee: 한화에어로스페이스(주)
Priority date: 2017-08-23
Filing date: 2018-03-27
Publication date: 2019-02-28
Also published as: KR102350919B1; KR20190021643A

Abstract

An apparatus for testing creep of a turbine blade comprises: a first support portion for supporting one end of a turbine blade; a plurality of elastic members, each having one side end connected to the other surface opposite to one surface of the first support portion, which faces toward the one end of the turbine blade, wherein at least a few of the elastic members have a different elastic modulus; a connection portion connected to the other side end of the elastic member to support the elastic member; a second support portion for supporting the other end of the turbine blade; an actuator for applying tensile force to at least one of the connection portion and the second support portion; and a heating portion disposed adjacent to a surface of the turbine blade so as to apply heat to the surface of the turbine blade.

Description

Creep test equipment for turbine blades

Embodiments relate to a creep test apparatus for a turbine blade, and more particularly to a creep test apparatus for a turbine blade capable of performing a precise test on creep deformation of a turbine blade by establishing the same conditions as actual operating conditions.

Turbine blades used in gas turbines and the like are used under operating conditions of a high rotational speed of a high temperature atmosphere, and when the turbine blades are subjected to a stress load for a long time, a deformation such as a creep occurs in the turbine blades.

Therefore, parts such as turbine blades used in high temperature and high speed rotation operating conditions need to be analyzed for damage taking into account the mechanical and thermal load applied during operation and the strength of material generated at high temperature.

Creep analysis and creep testing can be used to assess the life of a turbine blade at the design stage of the turbine blade or to verify the extent to which creep deformation has occurred by using turbine blades under actual operating conditions of the turbine, This is done to identify the cause of the damage.

A typical creep test apparatus such as that disclosed in U.S. Patent No. 5,425,276 applies stress in one direction (uniaxial direction) to a specimen that is formed to secure the creep property of the material. However, a creep test system with a force exerted only in the direction of the short axis can not transmit stresses similar to the operating environment in which the turbine blades are actually used to the turbine blades. As a result, the test specimen properties obtained by using the creep test apparatus which applies the force only in the direction of the short axis are not suitable for application to the turbine blades which are subjected to the stress load acting in various directions.

Another way to cope with the creep deformation of turbine blades is to perform a numerical analysis on the turbine blade considering the operating environment of the turbine blades in designing the turbine. However, there are limitations in the method of predicting the creep deformation of turbine blades using numerical analysis.

It is possible to consider the creep deformation of turbine blades used in actual operating conditions by operating the turbine according to the actual operating conditions, but there is a disadvantage that excessive cost is consumed.

Embodiments provide a creep test apparatus for a turbine blade capable of testing the creep deformation of a turbine blade by establishing operating conditions similar to actual operating conditions.

Embodiments provide a turbine blade creep test apparatus capable of performing an accurate creep deformation test by applying a tensile force having a magnitude and direction similar to the actual operating conditions to the turbine blade, not the uniaxial tensile force.

The apparatus for testing a creep of a turbine blade according to an embodiment includes a first support portion for supporting one end of the turbine blade and a second support portion for connecting one end of the turbine blade to the other surface of the first support portion facing the one end of the turbine blade, A plurality of elastic members having an elastic modulus; a connecting portion connected to the other end of the elastic member to support the elastic member; a second supporting portion for supporting the other end of the turbine blade; and a second supporting portion for applying a tensile force to at least one of the connecting portion and the second supporting portion An actuator, and a heating unit disposed adjacent to the surface of the turbine blade to apply heat.

The first support portion may include a plurality of moving blocks movable to contact the surface of the side surface of the turbine blade.

The moving block may be movably disposed between a position contacting the surface of the turbine blade by moving along one side of the first support and a position spaced from the surface of the turbine blade.

The first support portion may further include a flange protruding from one surface of the support portion and having a screw hole, and a set screw inserted in the screw hole and moving along the screw hole to press the movable block.

The flange can extend in the circumferential direction to form a space for accommodating one end of the turbine blade.

The actuator may include a first actuator that applies a tensile force to pull the connection portion away from the first support portion and a second actuator that applies a tensile force to pull the second support portion away from the turbine blade.

The plurality of heating portions are capable of heating different regions of the turbine blades in different temperature ranges so that the heating portions correspond respectively to different regions of the turbine blades.

The area corresponding to one end of the turbine blade of the areas of the turbine blade can be heated in a range of temperatures higher than the area corresponding to the other end of the turbine blade.

When the actuator applies a tensile force, the plurality of elastic members extend by the same length, so that a plurality of elastic members having mutually different elastic moduli can transmit forces of mutually different sizes to the turbine blades.

The first support portion may further include a coupling hole into which one end of the elastic member is inserted.

According to the creep test apparatus for turbine blades according to the embodiments as described above, stress, temperature and time conditions affecting the creep deformation of the turbine blades are made equal to the actual operating conditions, Precise testing can be carried out.

1 is a side view schematically showing a configuration of a creep test apparatus for a turbine blade according to an embodiment.

Fig. 2 is a block diagram schematically showing the connection relationship of the components of the creep test apparatus of the turbine blade according to the embodiment shown in Fig. 1;

3 is a perspective view showing some components of a creep test apparatus for turbine blades according to the embodiment shown in Fig.

Figure 4 is a side view of some components of the creep test apparatus of the turbine blade of Figure 3;

Fig. 5 is a perspective view showing the bottom of some components of the creep test apparatus of the turbine blade of Fig. 3;

Fig. 6 is a cross-sectional view showing the coupling relationship of some components of the creep test apparatus of the turbine blade of Fig. 3; Fig.

Fig. 7 is a perspective view exemplarily showing a coupling relationship of some components of the creep test apparatus of the turbine blade of Fig. 3;

Fig. 8 is a side view showing an operating state of some components of the creep test apparatus of the turbine blade of Fig. 3; Fig.

FIG. 9 is a flowchart showing steps of a creep test method using a creep test apparatus for a turbine blade according to the embodiment shown in FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the configuration and operation of a turbine blade creep test apparatus according to embodiments will be described in detail with reference to the accompanying drawings.

FIG. 1 is a side view schematically showing a configuration of a creep test apparatus for a turbine blade according to an embodiment, and FIG. 2 is a schematic view of a creep test apparatus for a turbine blade according to an embodiment shown in FIG. Fig.

The apparatus for testing a turbine blade creep according to the embodiment shown in Figs. 1 and 2 includes a first support portion 10 for supporting one end 7a of the turbine blade 7 and a second support portion 10 for supporting the other end 7b of the turbine blade 7 32, 33 provided between the turbine blade 7 and the connecting portion 40 and a connecting portion 40 (not shown) for supporting the

elastic members

31, 32,

Actuators

55 and 60 for applying a tensile force to at least one of the connecting portion 40 and the second supporting portion 20 and a heating portion 80 for applying heat to the turbine blades 7.

The

actuators

55 and 60 include a connecting portion 40 and a first actuator 55 for applying a tensile force to the first supporting portion 10 and a second actuator 60 for applying a tensile force to the second supporting portion 20. However, the embodiment is not limited by the number of

actuators

55, 60, and only one of the

actuators

55, 60 may be installed to apply a tensile force only to either the connecting portion 40 or the second supporting portion 20, for example. .

The turbine blades (7) function to generate rotational force by contacting with the hot combustion gas of the gas turbine. The turbine blade 7 has a shank at the other end 7b that can be connected to the body of the turbine blade assembly. A creep test apparatus for a turbine blade is a device for testing the creep deformation of the turbine blade 7 by applying a tensile force to pull one end (7a) and the other end (7b) of the turbine blade (7) in opposite directions.

Fig. 3 is a perspective view showing some components of the creep test apparatus of the turbine blade according to the embodiment shown in Fig. 1, Fig. 4 is a side view of some components of the creep test apparatus of the turbine blade of Fig. 3, Fig. 6 is a cross-sectional side view showing the engagement relationship of some components of the creep test apparatus of the turbine blade of Fig. 3; Fig. 6 is a perspective view showing a bottom surface of some components of the creep test apparatus of the turbine blade of Fig.

The first support portion 10 has a function of supporting one end 7a of the turbine blade 7 by disposing the first support portion 10 to face one end 7a of the turbine blade 7 do.

4 to 6, the first support portion 10 includes a first support portion 10 which is in contact with one end 10b of the turbine blade 7 and which extends downward from the first surface 10b and extends in the circumferential direction, A flange 10p having an inner space 10s accommodating one end 7a of the wing 7 and a plurality of moving blocks 15a to 15c movably arranged in the space 10s of the flange 10p, Respectively.

The moving blocks 15a to 15c move along the one surface 10b of the first support portion 10 so as to come into contact with the surface of the side surface of the turbine blade 7 and move to a position for supporting one end 7a of the turbine blade 7 Can be moved between a position spaced from the surface of the side surface of the turbine blade (7).

The flange 10p of the first support portion 10 has a screw hole 10h which is formed so as to penetrate from the outer side of the flange 10p toward the inner space 10s and has a screw surface formed on the inner surface thereof. The set screw 15s is engaged with the screw hole 10h of the flange 10p. The set screw 15s moves along the screw hole 10h to press the moving blocks 15a to 15c toward the surface of the side surface of the turbine blades 7 or to move the moving blocks 15a to 15c to the turbine blades 7, As shown in Fig.

One end portions 31b to 33b of the

elastic members

31, 32 and 33 are connected to the upper surface of the first support portion 10, that is, the other surface 10a of the first support portion 10. The first supporting portion 10 has a coupling hole 10g through which one end 31b of the elastic member 31 is inserted and fixed to the other surface 10a.

Since the

elastic members

31, 32 and 33 have elastic moduli different from each other, the elasticity of the

elastic members

31, 32 and 33 is increased by the action of the connecting members 40 pulling the elastic members 31, Different sized forces act. The three

elastic members

31, 32, and 33 do not have to have different elastic moduli, and at least some of them may have different elastic moduli. For example, the two elastic members may have the same elastic modulus and the other elastic member may have different elastic moduli.

The elastic modulus of each of the plurality of

elastic members

31, 32, and 33 may be derived using, for example, an inverse method. The first support portion 10 supports the one end 7a of the turbine blade 7 by using the inversion method so as to exhibit a stress distribution similar to the actual operating condition of the turbine blade 7 when the force is transmitted, The elastic modulus of each of the

elastic members

31, 32, and 33 can be calculated.

The elastic force of the

elastic members

31, 32, 33 is different from that of the

elastic members

31, 32, 33, The direction of the force transmitted to the one end 7a of the turbine blade 7 through the thrust bearing 7 may exhibit a stress distribution similar to the actual operating condition.

The connecting portions 40 are connected to the other end portions 31a to 33a of the

elastic members

31, 32 and 33. The connection portion 40 has a coupling hole 40g through which the other end portions 31a to 33a can be inserted and fixed. The connecting portion 40 has a substantially circular plate shape and supports the other end portions 31a to 33a of the

elastic members

31, 32 and 33 while transmitting the force transmitted through the first supporting shaft 50 to the

elastic members

31, 32, and 33, respectively.

The connection portion 40 has a first support shaft 50 for supporting the connection portion 40. The first support shaft 50 is formed in a substantially cylindrical shape, and the first support shaft 50 has a pin hole 50h into which an engagement pin can be inserted. Referring to FIG. 1, the first support shaft 50 is coupled to the expandable rod 55r of the first actuator 55 by an engagement pin 50p.

Referring to Fig. 1, the first actuator 55 includes a rod 55r which is driven by the power supplied from the actuator driver 92 and is movable (extendable and retractable) with respect to the tube 55t. The tube 55t of the first actuator 55 is supported by the frame 90. [

For example, the actuator driver 92 may be a hydraulic system including a hydraulic pump, a hydraulic valve, and the like to supply the hydraulic fluid, and the tube 55t may receive the hydraulic fluid to move the rod 55r. In addition to the hydraulic system, for example, a pneumatic system, an electric linear motor, or the like may be used for the first actuator 55. [

The rod 55r of the first actuator 55 moves in the direction away from the turbine blade 7, that is, in the direction toward the upper side in Fig. 1, so that the first support shaft 50 moves upward. As the first support shaft 50 moves upward, a tensile force acts on the turbine blades 7 to pull one end 7a of the turbine blades 7 in a direction away from the turbine blades 7.

1 and 4, the second support 20 has a concave shape 20t corresponding to the shank of the turbine blade 7 to support the other end 7b of the turbine blade 7 A block 21 and a second support shaft 22 protruding downward from the lower end of the block 21. The second support shaft 22 has a pin hole 20h into which the engagement pin can be inserted. Referring to Fig. 1, the second support shaft 22 is connected to the second actuator 60 by the engagement pin 60p.

The second actuator 60 is provided with a rod 60r which is received by the actuator driver 92 and is stretchable with respect to the tube 60t. Like the first actuator 55, the tube 60t of the second actuator 60 can receive the hydraulic fluid and move the rod 60r. The tube 60t of the second actuator 60 is supported by the frame 90. [

The rod 60r of the second actuator 60 moves in the direction away from the turbine blade 7, that is, in the direction toward the lower side in Fig. 1, so that the second support portion 20 moves downward. A tensile force acts on the turbine blade 7 to pull the other end 7b of the turbine blade 7 in a direction away from the turbine blade 7 as the second support portion 20 moves downward.

The first support portion 10 transmits the tensile force pulling the turbine blade 7 upward and the second support portion 20 simultaneously transmits the tensile force pulling the turbine blade 7 downward, Of the creep test operation is performed. However, the embodiment is not limited to such a configuration. For example, only the first actuator 55 operates to transmit a tensile force that pulls the turbine blade 7 upward only by the first support portion 10, and a separate actuator is not coupled to the second support portion 20, (20) can perform only a function of holding and supporting the turbine blade (7) without applying a separate tensile force to the turbine blade (7).

Referring to Figs. 1 and 7, a plurality of heating portions 80 are disposed adjacent to the surface 7s of the turbine blades 7. The heating section 80 functions to simulate the operating environment in which heat is transmitted to the turbine blades 7 when the turbine blades 7 are mounted on the turbine and actually used, by transferring heat to the turbine blades 7. [

Although four heating portions 80 are disposed adjacent to the surface 7s of the side surface of the turbine blade 7 in the drawing, the embodiment is not limited by the configuration of the heating portion 80 as described above. For example, the number of the heating units 80 may be changed, and the arrangement position of the heating units 80 may be different from that shown in the drawing. The heating unit 80 may be, for example, And an induction coil for generating heat as a result. The heating unit 80 is electrically connected to the thermal driver 92 provided in the frame 90 and the heating action of the heating unit 80 can be controlled by electricity transmitted from the thermal driver 92. [

The plurality of heating portions 80 may be disposed to correspond to different regions of the surface 7s of the turbine blades 7, respectively. Each of the plurality of heating portions 80 can heat different regions of the surface 7s of the turbine blade 7 in different temperature ranges.

For example, the heating section 80 includes a first coil 81, a second coil 82, a third coil 83, and a fourth coil 84. The first coil 81 and the second coil 82 also heat the upper regions 7a1 and 7a2 corresponding to one end 7a of the turbine blade 7 among different regions of the turbine blade 7. [ The third coil 83 and the fourth coil 84 heat the lower regions 7b1 and 7b2 corresponding to the other end 7b of the turbine blade 7 among the different regions of the turbine blade 7. [

For example, the upper regions 7a1 and 7a2 may be heated in a temperature range of 1,000 degrees to 1,300 degrees Celsius and the lower regions 7b1 and 7b2 may be heated in a temperature range of 700 degrees Celsius to 1000 degrees Celsius. The upper regions 7a1 and 7a2 corresponding to one end 7a of the turbine blade 7 can be heated to a higher temperature range than the lower regions 7b1 and 7b2 corresponding to the other end 7b.

The first coil 81 and the second coil 82 for heating the upper regions 7a1 and 7a2 of the turbine blade 7 can also operate in different temperature ranges. The upper front region 7a1 corresponding to the leading edge of the upper regions 7a1 and 7a2 can be heated by the first coil 81 in a temperature range of 1,100 to 1,300 degrees Celsius have. The upper rear region 7a2 corresponding to the trailing edge of the upper regions 7a1 and 7a2 can be heated by the second coil 82 in the temperature range of 1,000 to 1,200 degrees Celsius .

The third coil 83 and the fourth coil 84 for heating the lower regions 7b1 and 7b2 of the turbine blade 7 can also operate in different temperature ranges. For example, the lower front region 7b1 corresponding to the leading edge of the lower regions 7b1 and 7b2 may be heated by the third coil 83 in a temperature range of 800 to 1,000 degrees Celsius. The lower rear region 7b2 corresponding to the trailing edge of the lower regions 7b1 and 7b2 can be heated by the fourth coil 84 in the temperature range of 700 to 900 degrees Celsius.

As described above, in order for each of the first to fourth coils 81 to 84 of the heating section 80 to operate in different temperature ranges, a current of a different magnitude is applied to each of the first to fourth coils 81 to 84 .

Referring again to Figures 1 and 2, a controller 70 is connected to the creep testing apparatus of the turbine blade.

The controller 70 includes a tension controller 71 for applying a control signal to the actuator driver 91 to control the actuator driver 91, a thermal controller 72 for controlling the column driver 92, A user input receiving section 74 connected to the user interface 94 for receiving a user's input operation and generating a signal and a display controller 73 for controlling the display device 93 to operate on the turbine blades 7 A receiver 76 for receiving a signal of a sensor 95 for detecting a load and a temperature change related to a tensile force applied to the load 95 and a data receiver 77 for receiving or transmitting data from the storage 96, And a simulation condition setting unit 75 for setting simulation conditions for the creep test and generating control related information to be transmitted to the tension controller 71 and the thermal controller 72.

The controller 70 may be implemented by any one of, for example, a computer, a control circuit board, a control semiconductor chip mounted on a circuit board, control software embedded in a semiconductor chip or a computer, or a combination thereof.

One end 7a of the turbine blade 7 is supported by the moving blocks 15a to 15b of the first support portion 10 and the first support portion 10 is supported by the elastic members 31, (40). The upper surface of the connection portion 40 is connected to the first support shaft 50.

8, the tensile force is transmitted to the first supporting shaft 50 through the first supporting shaft 50, the connecting portion 40, the

elastic members

31, 32, 33 and the first supporting shaft 50, (7a) of the turbine blade (7) through the turbine blade (10).

In FIG. 8, the position of the connection portion 40 before the tensile force acts on the first support shaft 50 is shown by a dotted line. Since the tensile force does not act before the creep test apparatus starts to operate, the

elastic members

31, 32, and 33 are not stretched, so that the connection unit 40 is positioned at the initial position indicated by the dotted line.

When the creep test apparatus starts to operate, tensile force is transmitted through the first support shaft 50 and the connection portion 40 is pulled by the first support shaft 50 in the upward direction in FIG. When the connection portion 40 is pulled upward by the first support shaft 50, the connection portion 40 moves from the initial position shown by the dotted line to the position shown by the solid line. Since the

elastic members

31, 32 and 33 connected to the connection unit 40 have different elastic moduli from each other, the connection unit 40 moves in the direction away from the first support unit 10 and the

elastic members

31, 32 and 33 A different force is exerted on each of the

elastic members

31, 32, 33.

The elastic modulus of the first elastic member 31 of the

elastic members

31, 32 and 33 is K1 and the elastic modulus of the second elastic member 32 is K2, Assuming that the coefficient is K3 and the connecting portion 40 is moved upward by X distance to pull the

elastic members

31, 32 and 33, a force of a different magnitude is applied to each of the

elastic members

31, 32 and 33 .

The magnitude of the force acting on each of the

elastic members

31, 32 and 33 is F1> F2> K3, where K1> K2> K3, F3. The direction of the force acting on the turbine blades 7 through the first support 10 supporting the turbine blades 7 is not the direction of the arrows directed upwardly as shown in Figure 8 but the one end of the turbine blades 7 7a and directed in a direction twisted compared to the direction of the arrow, a force having a magnitude and direction similar to the actual operating conditions can be transmitted to the turbine blades 7. The bending moment is applied to the first support portion 10 because the force of different magnitudes acts on the first support portion 10 supporting the turbine blade 7 at three points by the elastic members 31, Lt; / RTI > Therefore, both the shear stress and the tensile stress are transmitted to the one end 7a of the turbine blade 7 through the first support portion 10 so that a force having a magnitude and direction similar to the actual operating conditions is transmitted to the turbine blade 7 .

A creep test method using a creep test apparatus of a turbine blade includes a step (S100) of calculating a temperature and a stress gradient by an analytical method by substituting a design condition of a turbine blade in a computer simulation program or an experimentally obtained turbine blade design function, (S110) of determining the direction and magnitude of the tensile force to be applied to the turbine blade for the creep test, determining the elastic modulus of each elastic member of the elastic member (S120), determining the arrangement position of the heating part and the temperature range (S140) of designing and fabricating the first support portion, the second support portion and the heating portion (S140), and performing a creep test (S150) by mounting the turbine blade to the test apparatus.

In step S110 of determining the direction and magnitude of the tensile force, an inverse method may be used to determine the magnitude and direction of the tensile force applied to the first support to exhibit a stress distribution similar to the actual operating conditions.

In the step of determining the elastic modulus (S120), the elastic modulus of each elastic member can be determined so as to realize the magnitude and direction of the determined tensile force.

In the step of determining the position and temperature of the heating part (S130), it is possible to invert the numerical values of the position and the temperature at which the heating part should be arranged so that the temperature distribution similar to the actual operating condition can be expressed using the inverse calculation method.

The creep test method using the creep test apparatus of the turbine blade as described above is a stress, temperature, and time that affect the creep deformation of the turbine blade. can do.

The apparatus and method for creep testing of turbine blades according to the above embodiments are useful for testing turbine blades produced by 3D printing. Using 3D printing, various shapes of turbine blades can be manufactured using various materials. However, if the turbine blade prepared by the 3D printing method is mounted directly on the turbine and there is a limitation such as the cost and the time required, the creep test apparatus and test method of the turbine blade according to the above- The manufactured turbine blades can be tested precisely and quickly under conditions very similar to actual operating conditions.

The construction and effect of the above-described embodiments are merely illustrative, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Accordingly, the true scope of protection of the invention should be determined by the appended claims.

Claims

A first support for supporting one end of the turbine blade;

A plurality of elastic members having one side end connected to the other side opposite to one surface of the first support portion facing the one end of the turbine blade and at least a portion having a different elastic modulus;

A connecting portion connected to the other end of the elastic member to support the elastic member;

A second support for supporting the other end of the turbine blade;

An actuator for applying a tensile force to at least one of the connection portion and the second support portion; And

And a heating portion disposed adjacent to the surface of the turbine blade and applying heat thereto.
The method according to claim 1,

Wherein the first support portion comprises a plurality of moving blocks movable to contact a surface of a side surface of the turbine blade.
3. The method of claim 2,

Wherein the moving block is movably disposed between a position contacting the surface of the turbine blade and a position spaced from the surface of the turbine blade by moving along the one side of the first support, Device.
3. The method of claim 2,

Wherein the first support portion further comprises a flange projecting from the one surface of the support portion and having a screw hole and a set screw inserted in the screw hole to press the moving block by moving along the screw hole, Creep test equipment.
5. The method of claim 4,

Said flange extending circumferentially to define a space for receiving said one end of said turbine blade.
The method according to claim 1,

Wherein the actuator includes a first actuator that applies a tensile force to pull the connection portion away from the first support portion and a second actuator that applies a tensile force to pull the second support portion away from the turbine blade, Test equipment.
The method according to claim 1,

Wherein the plurality of heating portions heat the different regions of the turbine blades in different temperature ranges, wherein the plurality of heating portions heat the different regions of the turbine blades in different temperature ranges, the plurality of heating portions corresponding to the different regions of the turbine blades, respectively.
8. The method of claim 7,

Wherein an area corresponding to said one end of said turbine blade in said areas of said turbine blade is heated in a range of temperatures higher than a temperature corresponding to said other end of said turbine blade.
8. The method of claim 7,

Wherein the plurality of elastic members extend by the same length when the actuator applies the tensile force so that the plurality of elastic members having different elastic moduli transmit forces different in magnitude from each other to the turbine blades.
The method according to claim 1,

Wherein the first support portion further comprises a coupling hole into which the one end of the elastic member is inserted, on the other surface of the turbine blade.