KR102654746B1 - Blade inspection device of gas turbine - Google Patents

Abstract

An embodiment of the present invention is intended to provide a gas turbine blade inspection device that can quickly and easily detect defects in the internal passage of a blade fastened to the rotor of a power generation gas turbine based on electrodynamic impedance (EMI). The gas turbine blade inspection device according to an embodiment of the present invention contacts one surface of the blade coupled to the rotor of the gas turbine and measures the impedance value for each blade point under certain preset boundary conditions using an electrodynamic impedance method, and the rotor A detection unit that detects the impedance difference corresponding to the excitation and generates the corresponding impedance detection value, a drive unit that generates the moving force of the detection unit, and a guide rod-shaped one side is axially connected to the drive unit and the detection unit is coupled to the other side, and the drive unit It includes a follower part that is linked to the drive of and guides the axial movement of the detection part.

Description

Blade inspection device for gas turbine {BLADE INSPECTION DEVICE OF GAS TURBINE}

The present invention relates to a gas turbine blade inspection device.

Blades fastened to the rotor of a gas turbine for power generation are inspected in two main situations. The first is when the blade is separated from the rotor and inspected, and the second is when the blade is inspected with the blade fastened to the rotor. In cases where the blades are separated from the rotor and a complete inspection is conducted when there is a special defect in the blades or during a designated Class A planned preventive maintenance period.

Next, the inspection with the blades fastened to the rotor is a general maintenance inspection during the planned preventive maintenance period. If a defect is found in the inspection of the blades fastened to the rotor, the blades are disassembled from the rotor and inspected closely. In this way, inspecting defects while the blade is fastened to the rotor is a very important element in maintenance inspection during the planned preventive maintenance period.

Meanwhile, blade inspection when the blade is fastened to the rotor includes liquid penetrant examination, eddy current test, and ultrasonic testing.

However, the inspection method for blades fastened to the rotor of a gas turbine according to the prior art has a limited inspection range, and the result is unclear due to differences in the inspector's skills. In addition, blades fastened to the rotor of a gas turbine have cooling holes on the inside and outside for blade cooling, and defects occur in the internal flow path of the blade. There is a need to develop technology that can inspect such blade defects. .

An embodiment of the present invention is intended to provide a gas turbine blade inspection device that can quickly and easily detect defects in the internal passage of a blade fastened to the rotor of a power generation gas turbine based on electrodynamic impedance (EMI).

The gas turbine blade inspection device according to an embodiment of the present invention contacts one surface of the blade coupled to the rotor of the gas turbine and measures the impedance value for each blade point under certain preset boundary conditions using the electrodynamic impedance (EMI) method. A detection unit that detects the impedance difference corresponding to the excitation of the rotor and generates the corresponding impedance detection value, a drive unit that generates the moving force of the detection unit, and a guide rod shape, one side of which is axially connected to the drive unit, and the detection unit is coupled to the other side. It includes a follower unit that guides the axial movement of the detection unit in conjunction with the driving of the drive unit.

The detection unit is provided in response to the shape of the blade, a contact medium that transmits the response wave of the blade, a piezoelectric material that transmits the excited energy to the blade through the contact medium and receives the response wave of the blade, and the excitation and response of the piezoelectric material. Backing epoxy that removes back reflected waves, a conductive ring that keeps one side of the piezoelectric material as ground, one side is electrically connected to the piezoelectric material, and the other side is electrically connected to a wire to form a data collection unit (DAQ). ; Data Acquisition) may include a matching unit that transmits the signal generated from the piezoelectric material to the piezoelectric material, and a load cell that measures the contact pressure where the blade and the detection unit contact.

It is coupled to the driven part and provided between the driving part and the detecting part, and may further include a guide part that guides the contact position when one side of the detecting part contacts one surface of the blade.

The guide part includes a guide laser, and the measuring point can be confirmed with the point of the guide laser, and the detection part can be brought into contact with the measuring point of the blade with a preset contact pressure by driving the driving part.

When the contact pressure measured by the load cell reaches a preset certain value, the operation of the driving unit may be stopped.

The driving unit includes a submotor and can support a contact pressure of a preset constant value by analyzing the impedance detection value input from the detection unit.

The impedance value of the blade can be easily measured by measuring the electrodynamic impedance (EMI) by contacting the easily fastened detector with the blade. By analyzing the measurement signal, the presence or absence of internal and external defects of the blade can be quickly determined with a short measurement time per blade. There is an effect that can be easily inspected.

Figure 1 is a diagram showing a gas turbine blade inspection device according to an embodiment of the present invention.
Figure 2 is a diagram schematically showing a blade inspection state using a gas turbine blade inspection device according to an embodiment of the present invention.
Figures 3 and 4 are diagrams illustrating EMI status diagnosis results.

The terminology used herein is only intended to refer to specific embodiments and is not intended to limit the invention. As used herein, singular forms include plural forms unless phrases clearly indicate the contrary. As used in the specification, the meaning of "comprising" is to specify a specific characteristic, area, integer, step, operation, element, and/or component, and to specify another specific property, area, integer, step, operation, element, component, and/or group. It does not exclude the existence or addition of .

Although not defined differently, all terms including technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries are further interpreted as having meanings consistent with related technical literature and currently disclosed content, and are not interpreted in ideal or very formal meanings unless defined.

Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein.

Figure 1 is a diagram showing a blade inspection device for a gas turbine according to an embodiment of the present invention, and Figure 2 is a diagram schematically showing a blade inspection state using a blade inspection device for a gas turbine according to an embodiment of the present invention. , Figure 3 is a diagram illustrating the results of EMI status diagnosis.

Referring to FIGS. 1 to 3, the gas turbine blade inspection device according to an embodiment of the present invention includes a detection unit (1), a driver unit (4), and a follower unit (3), and a rotor (100) of a gas turbine for power generation. ) can be easily inspected for defects in the internal passage of the blade 110 fastened to the.

The gas turbine blade inspection device according to an embodiment of the present invention is a rotor fastened blade inspection device using the EMI (Electro-Mechanical Impedance) method. During the planned preventive maintenance period of a power plant, the rotor 100 to which the blades 110 are fastened is separated from the housing for maintenance. The blades 110 fastened to the rotor 100 mounted on a rotating shelf can be inspected.

The detection unit 1 contacts one surface of the blade 110 coupled to the rotor 100 of the gas turbine and detects the impedance ( Impedance) value is measured, and the impedance difference corresponding to the excitation of the rotor 100 is detected to generate the corresponding impedance detection value. The detection unit 1 functions as an inspection sensor that excites the rotor 100 by contacting the blade 110 and analyzes the resulting impedance difference.

The driving unit 4 generates a moving force of the detection unit. The driving unit 4 includes a submotor and analyzes the impedance detection value input from the detection unit 1 to support a contact pressure of a preset constant value.

The driven part 3 has a guide rod shape, one side is axially connected to the driving part 4, and the other side is coupled to the detecting part 1, and is linked to the driving of the driving part 4 to guide the axial movement of the detecting part.

The gas turbine blade inspection device according to an embodiment of the present invention is coupled to the driven part 3 and provided between the driving part 4 and the detecting part 1, and one side of the detecting part 1 is one side of the blade 110. It further includes a guide portion (2) that guides the contact position when contacting.

The guide unit 2 includes a guide laser, and the measurement point is confirmed with the point of the guide laser, and the detection unit 1 is driven by the drive unit 4 to contact the detection unit 1 with a preset contact pressure to the measurement point of the blade 110. The guide unit 2 is a guide laser and functions as a sensor to determine the contact position when the first detection unit 1 contacts the blade 110.

Meanwhile, the rotor 100 is rotated using rotation motors installed at both ends of the rotor 100, and data can be acquired for each blade point and analyzed with analysis equipment. Here, the analysis equipment confirms the measurement point with the guide unit 2 and drives the drive unit 4 to perform a series of control operations that bring the contact medium 5 of the detection unit 1 into contact with the blade 110. The pressure in contact with the blade 110 is calculated as a measured value by the detection unit 1, and when it reaches a certain value, the operation of the drive unit 4 can be stopped. As a result, the impedance value can be measured at each blade point under certain boundary conditions, and the result of the presence or absence of surface defects of the blade 110 can be analyzed using this.

The analysis equipment analyzes the state signals for the presence or absence of defects inside and outside the blade 110 supplied from the detection unit 1 and can perform overall control operations related to inspection for the presence or absence of defects inside and outside the blade 110. For example, the analysis equipment controls the operation of the driving unit 4 and the control operations related to the inspection of the internal and external defects of the blade 110 of the detection unit 1 according to preset inspection control conditions for defects inside and outside the blade 110. can do. The analysis equipment may include a timer.

Analysis equipment is a logical part of a program that performs calculations and processing by the processor of an information processing device and performs a specific function on a computer, and can be implemented in software, hardware, etc. For example, information processing devices include personal computers, handheld computers, personal digital assistants (PDAs), programmable logic controllers (PLCs), mobile phones, smart devices, and tablets. For example, the analysis equipment may be programmed in a computer or PLC with a program related to the inspection of the internal and external defects of the blade 110 and operated to perform overall control operations related to the inspection of the internal and external defects of the blade 110.

The analysis equipment may be separately equipped with a memory that stores data related to inspection of the internal and external defects of the blade 110. Memory is a device that controls program control and information processing related to inspection of internal and external defects of the blade 110 and stores related data and programs, such as high-speed random access memory, magnetic disk storage device, and flash memory. It may include various types of memory, such as non-volatile memory such as devices and other non-volatile solid-state memory devices. For example, reference values for inspection of internal and external defects of the blade 110 may be set and stored in the memory.

Referring to Figures 1 and 2, the detection unit (1) includes a contact medium (5), a piezoelectric material (6), a backing epoxy (7), a conductive ring (8), a matching unit (9), and a load cell (10). ), and the presence or absence of defects inside and outside the blades 110 fastened to the rotor can be inspected using electro-mechanical impedance (EMI).

The contact medium 5 is provided to correspond to the shape of the blade 110 and transmits the response wave of the blade 110.

The piezoelectric material 6 transmits excited energy to the blade 110 through the contact medium 5 and includes a piezoelectric sensor that receives the response wave of the blade 110. The material and size of the piezoelectric material 6 can be set in consideration of the size and size of the blade 110.

The backing epoxy 7 is formed in consideration of the excitation and responsiveness of the piezoelectric material 6 to eliminate back-reflected waves.

The conductive ring 8 maintains one surface of the piezoelectric material 6 as ground.

One side of the matching unit 9 is electrically connected to the piezoelectric material 6 and the other side is electrically connected to a wire to transmit a signal generated from the data acquisition unit (DAQ) to the piezoelectric material 6.

The load cell 10 measures the contact pressure between the blade 110 and the detection unit 1. When the contact pressure measured by the load cell 10 reaches a preset constant value, the operation of the drive unit 4 is stopped.

As described above, when using the gas turbine blade inspection device according to the embodiment of the present invention, the blades 110 fastened to the rotor 100 are inspected using electro-mechanical impedance (EMI). ) The presence or absence of internal and external defects can be determined. Blade damage evaluation based on electrodynamic impedance (EMI) can excite the blade 110 using a piezoelectric method and simultaneously inspect changes in the electrical and mechanical impedance of the blade 110. At this time, the impedance (Zs) of the blade 110 becomes the impedance (Za) of the piezoelectric material 6, and the electrical impedance value linked to the piezoelectric material 6 and the blade 110 can be calculated using a preset formula. . As a result, when the electrodynamic impedance (EMI) is measured by contacting the detection unit 1 according to an embodiment of the present invention to the blade 110, the impedance (Zs) value of the blade 110 can be measured, and the measurement signal Through analysis, the presence or absence of internal and external defects of the blade 110 can be determined.

When inspecting the blade 110 with the detection unit 1 according to an embodiment of the present invention, fastening is easy and the measurement time per blade 110 is short (less than 5 minutes), so the presence or absence of a defect in the blade 110 can be quickly determined. there is. As a result, the final result obtained is displayed as shown in FIGS. 3 and 4, and the resulting data can be analyzed later and used to determine the presence or absence of defects inside and outside the blade 110, the state of constraints, etc. The embodiment of the present invention accumulates data on gas turbine blades developed domestically in relation to the government project 'Development of performance verification technology for gas turbine blade prototypes of F (1350'C) class or higher' to improve maintenance and stability of domestically produced turbine blades. can contribute to

Although preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and can be implemented with various modifications within the scope of the claims, the detailed description of the invention, and the accompanying drawings, and this is also possible. It is natural that it falls within the scope of the present invention.

One ; Detection unit 2; Guide department
3 ; Follower 4 ; driving part
5 ; contact medium 6; Piezoelectric material
7 ; backing epoxy 8; conductive ring
9 ; Matching unit 10; load cell
100 ; rotor 110; blade

Claims (9)

By contacting one surface of the blade coupled to the rotor of the gas turbine, the impedance value is measured for each blade point under certain preset boundary conditions using the electro-mechanical impedance (EMI) method, and the excitation of the rotor is measured. A detection unit that detects the corresponding impedance difference and generates a corresponding impedance detection value, and checks changes in the electrical impedance and mechanical impedance of the blade to generate a status signal for the presence or absence of internal and external defects of the blade,
A driving unit that generates a moving force of the detection unit, and
A follower part has a guide rod shape, one side of which is axially connected to the driving part, and the detection part is coupled to the other side, and is linked to the driving of the driving part to guide the axial movement of the detecting part.
Includes,
The detection unit
A contact medium provided to correspond to the shape of the blade and transmitting the response wave of the blade,
A piezoelectric material that transmits excited energy to the blade through the contact medium and receives a response wave from the blade,
A matching unit that has one side electrically connected to the piezoelectric material and the other side electrically connected to a wire to transmit a signal generated from a data acquisition unit (DAQ) to the piezoelectric material;
A backing epoxy formed in consideration of the excitation and responsiveness of the piezoelectric material to remove back reflected waves,
A conductive ring that maintains one surface of the piezoelectric material as ground, and
A load cell that measures the contact pressure of the blade and the detection unit.
Includes,
The measurement point is confirmed by the guide unit, the drive unit is driven to perform a series of control operations that bring the contact medium of the detection unit into contact with the blade, the impedance value is measured at each blade point, and the presence or absence of surface defects of the blade is determined using this. It further includes analysis equipment to analyze the results,
The impedance (Zs) of the blade becomes the impedance (Za) of the piezoelectric material, and the electrical impedance value linked to the piezoelectric material and the blade is calculated in a preset manner, so that the electrodynamic impedance is measured by contacting the detection unit with the blade. A gas turbine blade inspection device that measures (EMI) and analyzes the impedance (Zs) value of the blade to determine the presence or absence of internal and external defects of the blade.
delete delete delete delete In paragraph 1:
A gas turbine blade inspection device in which operation of the driving unit is stopped when the contact pressure measured by the load cell reaches a preset constant value. In paragraph 6:
A blade inspection device for a gas turbine wherein the driving unit includes a submotor, and supports a contact pressure of a preset constant value by analyzing the impedance detection value input from the detection unit. In paragraph 1:
The guide part is coupled to the driven part and provided between the driving part and the detection part, and guides the contact position when one side of the detection part contacts one surface of the blade. In paragraph 8:
The guide unit includes a guide laser,
A gas turbine blade inspection device that confirms the measurement point with the point of the guide laser and contacts the detection unit with a preset contact pressure to the measurement point of the blade by driving the drive unit.