CN113124792B - Method for measuring bonding area of large-scale high-speed rotating equipment based on non-contact ultrasound - Google Patents

Abstract

The invention proposes a method for measuring the bonding area of large-scale high-speed rotating equipment based on non-contact ultrasound, so that the pulsed laser emitted by the laser is irradiated on the upper surface of the first rotor part through the beam splitter and the first lens; The pulsed laser of the mirror; enables the confocal Fabry-Perot interferometer to receive the ultrasonic signal on the upper surface of the first rotor part; the data acquisition card combines the electrical signal from the photodetector with the ultrasonic wave from the confocal Fabry-Perot interferometer The signal is converted into a digital signal, and the digital signal is transmitted to the industrial computer for storage and data processing; using the corresponding relationship between the amplitude A _i and the bonding area Si _, the bonding between the first rotor part and the second rotor part at the current detection position is obtained. combined area. The invention realizes the non-contact non-destructive measurement of the bonding area of large-scale high-speed rotary equipment, and simultaneously the excitation and reception of laser ultrasound are completed in an instant, which can realize fast and real-time measurement, and has strong anti-interference ability.

Description

Measurement method of bonding area of large-scale high-speed rotary equipment based on non-contact ultrasound

technical field

The invention relates to a method for measuring the bonding area of large-scale high-speed rotary equipment based on non-contact ultrasound, and belongs to the technical field of measurement.

Background technique

Large-scale high-speed slewing equipment such as aero-engines or gas turbines has become a bottleneck problem in the field of high-end equipment manufacturing in my country due to its complex technology, difficult development and other characteristics, coupled with European and American technology blockades. Aero-engine or gas turbine systems are generally assembled from multi-stage rotors, and the surfaces of the rotors in contact with each other are called joint surfaces. These microscopically rough contact surfaces make the system no longer continuous. The mechanical properties of an aero-engine or gas turbine system are not only related to the rotor parts themselves, but also to the connection properties between the rotors. The existence of joint surfaces complicates the analysis and prediction of system performance. The assembly quality between the rotors at all levels has a great impact on the performance of large-scale high-speed rotary equipment such as aero-engines or gas turbines. During the assembly process, if there is non-uniformity in the bonding area of the rotor connection interface, the deformation of the aero-engine or gas turbine at high speed will be non-uniform, and the imbalance of the rotor will change greatly, which will eventually lead to The engine vibrates during operation. More than 90% of the failures of turbofan aero-engines originate from vibration, which is one of the reasons why my country's aero-engines need to be overhauled after working for hundreds of hours. Therefore, it is urgent to precisely measure the bonding area of the engine rotor. Only when the measurement is precise, can the assembly be accurate.

At present, the measurement of the bonding area is mainly by setting a pressure-sensitive film or applying red dan powder on the contact interface of the rotor, and by observing the change of the pressure-sensitive film or red dan powder after assembly to judge the contact situation, and then calculate the bonding area. The method changes the contact state of the interface, which cannot reflect the real contact situation and affects the measurement results. The ultrasonic method can achieve non-destructive measurement of the contact characteristics of the joint surface without changing the contact state of the workpiece. The nominal contact area can be directly obtained by scanning the joint surface with an ultrasonic probe. Therefore, scholars at home and abroad have carried out extensive research on ultrasonic measurement methods. . Traditional ultrasonic technology mostly uses contact transducers. In order to ensure high sensitivity and reliability, various ultrasonic couplants are usually used. Ultrasonic waves need a certain transit time when passing through the coupling agent, and will produce interference harmonics. wave, which will bring unstable factors to the measurement, and the use of couplant will increase the extra workload, resulting in low measurement efficiency, and more seriously, it will cause certain corrosion and damage to the surface of the aero-engine or gas turbine rotor. The traditional ultrasonic method is limited in practical application.

SUMMARY OF THE INVENTION

The present invention proposes a method for measuring the bonding area of large-scale high-speed rotary equipment based on non-contact ultrasound. and other problems, to achieve direct, high-efficiency and high-precision measurement of the bonding area of large-scale high-speed rotary equipment.

A method for measuring the bonding area of large-scale high-speed rotary equipment based on non-contact ultrasound is applied to a large-scale high-speed rotary equipment bonding area measurement device based on laser ultrasound. The measurement device includes: a laser, a beam splitter, a first lens, a confocal Fabry- Perot interferometer, data acquisition card, second lens, photodetector, industrial computer, first rotor part and second rotor part, the output end of the confocal Fabry-Perot interferometer and the output end of the photodetector All are connected to the input end of the industrial computer through the data acquisition card, and the output end of the industrial computer is respectively connected to the input end of the laser and the input end of the Fabry-Perot interferometer. The first lens is arranged at an angle of 45° obliquely above the first rotor member from far to near relative to the first rotor member, the laser is arranged coaxially with the first lens, the photodetector and the The second lens is coaxially arranged on the reflected light path of the spectroscope from far to near relative to the spectroscope, the confocal Fabry-Perot interferometer is arranged above the first rotor part, and the The first rotor part and the second rotor part are connected by a flange bolt structure, and the measurement method includes the following steps:

Step 1: Adjust the position and posture of the laser, the spectroscope and the first lens, so that the pulsed laser emitted by the laser is irradiated on the upper surface of the first rotor part through the spectroscope and the first lens;

Step 2: Adjust the position and attitude of the second lens and the photodetector, so that the photodetector receives the pulsed laser light from the beam splitter;

Step 3, adjust the position and posture of the confocal Fabry-Perot interferometer, so that the confocal Fabry-Perot interferometer can receive the ultrasonic signal on the upper surface of the first rotor part;

Step 4. The industrial computer sends an instruction to make the laser emit pulsed laser light. The pulsed laser light is divided into two beams by the beam splitter. One of the pulsed laser beams is incident on the photodetector through the second lens and is converted into an electrical signal and transmitted to the The data acquisition card is used as a trigger for the acquisition of ultrasonic signals. After passing through the first lens, another pulsed laser is focused on the upper surface of the first rotor part and excites ultrasonic waves inside the first rotor part, and the ultrasonic waves propagate inside the first rotor part. And reach the joint surface of the first rotor part and the second rotor part, part of the ultrasonic wave continues to propagate through the joint surface, and another part of the ultrasonic wave is reflected back to the upper surface of the first rotor part to be received by the confocal Fabry-Perot interferometer and transmitted to Data acquisition card, the data acquisition card converts the ultrasonic signal from the confocal Fabry-Perot interferometer and the electrical signal from the photodetector into digital signals, and transmits the digital signals to the industrial computer for storage and data processing;

Step 5. Extract the amplitude A _i of the ultrasonic signal _{Vi from the data signal, and use the corresponding relationship between the amplitude A i and the} bonding area Si to obtain the bonding between the first rotor part and the second rotor part at the current detection position. area.

Further, in step 5, the corresponding relationship between the amplitude A _i and the bonding area S _i is obtained by calibration, namely:

S _i =CA _i (1)

Among them, C is the relationship coefficient between the ultrasonic signal amplitude A _i and the bonding area Si obtained from the experimental calibration _.

The present invention has the following beneficial effects:

(1) The laser and the confocal Fabry-Perot interferometer are used to realize the excitation and reception of the ultrasonic method respectively, and the non-contact non-destructive measurement of the bonding area can be realized, which can avoid the use of the liquid couplant necessary in the traditional ultrasonic method, thus eliminating the need for The couplant corrodes and contaminates the surface of the test piece, and the excitation and reception of laser ultrasound are completed in an instant, which can realize fast and real-time measurement, and has strong anti-interference ability;

(2) The laser beam can be focused into a very small point, so the spatial resolution of the measurement of the bonding area of large-scale high-speed rotary equipment can be improved.

Description of drawings

Figure 1 is a schematic diagram of the structure of a large-scale high-speed rotary equipment bonding area measurement device based on laser ultrasound.

Among them, 1 is the laser, 2 is the beam splitter, 3 is the first lens, 4 is the confocal Fabry-Perot interferometer, 5 is the data acquisition card, 6 is the second lens, 7 is the photodetector, 8 is the industrial computer, 9 is the first rotor part and 10 is the second rotor part.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Referring to Figure 1, the method for measuring the bonding area of large-scale high-speed rotary equipment based on non-contact ultrasound is applied to a large-scale high-speed rotary equipment bonding area measurement device based on laser ultrasound. The measurement device includes: a laser 1, a spectroscope 2, a first Lens 3, confocal Fabry-Perot interferometer 4, data acquisition card 5, second lens 6, photodetector 7, industrial computer 8, first rotor part 9 and second rotor part 10, confocal Fabry-Perot interferometer The output end of 4 and the output end of the photodetector 7 are connected with the input end of the industrial computer 8 through the data acquisition card 5, and the output end of the industrial computer 8 is respectively connected with the input end of the laser 1 and the input end of the Fabry-Perot interferometer 4. connected, the laser 1, the beam splitter 2 and the first lens 3 are arranged on the 45° angle obliquely above the first rotor member 9 from far to near relative to the first rotor member 9, and the laser 1 and the first lens 3 are coaxially arranged, The photodetector 7 and the second lens 6 are coaxially arranged on the reflected light path of the spectroscope 2 from far to near relative to the spectroscope 2. The confocal Fabry-Perot interferometer 4 is arranged above the first rotor part 9, and the first The rotor part 9 is connected with the second rotor part 10 through a flange bolt structure, and the measurement method includes the following steps:

Step 1, adjust the position and attitude of the laser 1, the spectroscope 2 and the first lens 3, so that the pulsed laser light emitted by the laser 1 is irradiated on the upper surface of the first rotor part 9 by the spectroscope 2 and the first lens 3;

Step 2, adjust the position and attitude of the second lens 6 and the photodetector 7, so that the photodetector 7 receives the pulsed laser from the beam splitter 2;

Step 3, adjust the position and posture of the confocal Fabry-Perot interferometer 4, so that the confocal Fabry-Perot interferometer 4 can receive the ultrasonic signal on the upper surface of the first rotor part 9;

Step 4. The industrial computer 8 sends an instruction to make the laser 1 emit pulsed laser light. The pulsed laser light is divided into two beams by the beam splitter 2. One of the pulsed laser beams is incident on the photodetector 7 through the second lens 6 and then converted into an electrical signal for transmission to data acquisition. Card 5, as a trigger for the acquisition of ultrasonic signals, another pulsed laser beam passes through the first lens 3 and then focuses on the upper surface of the first rotor part 9 and excites ultrasonic waves inside the first rotor part 9, and the ultrasonic waves in the first rotor part 9 The interior propagates and reaches the joint surface of the first rotor part 9 and the second rotor part 10, part of the ultrasonic wave continues to propagate through the joint surface, and another part of the ultrasonic wave is reflected back to the upper surface of the first rotor part 9 by the confocal Fabry-Perot interferometer 4 Receive and transmit to the data acquisition card 5, the data acquisition card 5 converts the ultrasonic signal from the confocal Fabry-Perot interferometer 4 and the electrical signal from the photodetector 7 into digital signals, and transmits the digital signals to the industrial computer 8 for storage and data processing;

Step 5: Extract the amplitude A _i of the ultrasonic signal V _i from the data signal, and use the corresponding relationship between the amplitude A _i and the bonding area S _i to obtain the current detection position of the first rotor part 9 and the second rotor part 10 . Fitting area.

In the preferred embodiment of this part, in step 5, the corresponding relationship between the amplitude A _i and the bonding area S _i is obtained by calibration, namely:

S _i =CA _i (1)

Among them, C is the relationship coefficient between the ultrasonic signal amplitude A _i and the bonding area Si obtained from the experimental calibration _.

Specifically, the industrial computer 8 controls the time, pulse energy and laser emission frequency of the laser 1 to emit laser light.

The large-scale high-speed rotary equipment described in the present invention takes objects such as aero-engines or gas turbines as an example, and is specifically limited to the rotary equipment whose size and height are greater than 3m, diameter is greater than 1.5m, and rotational speed is greater than 15,000 rpm.

Claims (2)

1. A method for measuring the bonding area of large-scale high-speed rotary equipment based on non-contact ultrasound is characterized in that the method is applied to a device for measuring the bonding area of large-scale high-speed rotary equipment based on laser ultrasound, and the measuring device comprises: laser (1), spectroscope (2), first lens (3), confocal Fabry-Perot interferometer (4), data acquisition card (5), second lens (6), photodetector (7), industrial personal computer (8), first rotor component (9) and second rotor component (10), the output of confocal Fabry-Perot interferometer (4) and the output of photodetector (7) are connected with the input of industrial personal computer (8) through data acquisition card (5), the output of industrial personal computer (8) is connected with the input of laser (1) and the input of Fabry-Perot interferometer (4), laser (1), spectroscope (2) and first lens (3) are arranged in sequence above the first rotor component (9) from far to near at an angle of 45 ° relative to the oblique angle of the first rotor component (9), laser (1) is arranged coaxially with the first lens (3), photodetector (7) and second lens (6) are arranged coaxially with respect to the first rotor component (2) above the near to the reflected light of the spectroscope (2) in sequence, and the reflected light of the first rotor component (9) is arranged coaxially with the second rotor component (9) through the second rotor component (10), and the confocal Fabry-Perot interferometer (9) is arranged coaxially above the second rotor component (4) through the flange structure, the measuring method comprises the following steps:

adjusting the positions and postures of the laser (1), the spectroscope (2) and the first lens (3) to enable pulse laser emitted by the laser (1) to irradiate the upper surface of the first rotor component (9) through the spectroscope (2) and the first lens (3);

adjusting the positions and postures of the second lens (6) and the photoelectric detector (7) to enable the photoelectric detector (7) to receive pulse laser from the spectroscope (2);

adjusting the position and the posture of the confocal Fabry-Perot interferometer (4) to enable the confocal Fabry-Perot interferometer (4) to receive the ultrasonic signal of the upper surface of the first rotor component (9);

the industrial personal computer (8) sends an instruction to enable the laser (1) to emit pulse laser, the pulse laser is divided into two beams by the spectroscope (2), one beam of pulse laser is incident to the photoelectric detector (7) through the second lens (6) and then converted into an electric signal to be transmitted to the data acquisition card (5) to be used as acquisition trigger of an ultrasonic signal, the other beam of pulse laser is focused on the upper surface of the first rotor component (9) through the first lens (3) and excites an ultrasonic wave inside the first rotor component (9), the ultrasonic wave is transmitted inside the first rotor component (9) and reaches a joint surface of the first rotor component (9) and the second rotor component (10), a part of the ultrasonic wave penetrates through the joint surface to be continuously transmitted, the other part of the ultrasonic wave is reflected to the upper surface of the first rotor component (9) and is received by the confocal Fabry-Perot interferometer (4) and transmitted to the data acquisition card (5), and the data acquisition card (5) converts the ultrasonic signal transmitted by the photoelectric detector (7) and the photoelectric signal transmitted by the confocal Fabry-Perot interferometer (4) into a digital signal and transmits the digital signal to the industrial personal computer (8) for data processing and data processing;

step five, extracting the ultrasonic signal V from the data signal _i Amplitude A of _i Using amplitude A _i And the bonding area S _i The corresponding relation between the first rotor component and the second rotor component obtains the bonding area of the first rotor component (9) and the second rotor component (10) at the current detection position.

2. The non-contact ultrasound-based large-scale high-speed slewing equipment bonding area measurement method according to claim 1,in step five, the amplitude A _i And the bonding area S _i The corresponding relation between the two is obtained by calibration, namely:

S _i ＝CA _i (1)

wherein, C is ultrasonic signal amplitude A obtained by experimental calibration _i And the bonding area S _i Coefficient of the relationship between them.

Images