CN206177542U - Fatigue test device of engine blade - Google Patents
Fatigue test device of engine blade Download PDFInfo
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- CN206177542U CN206177542U CN201621063217.8U CN201621063217U CN206177542U CN 206177542 U CN206177542 U CN 206177542U CN 201621063217 U CN201621063217 U CN 201621063217U CN 206177542 U CN206177542 U CN 206177542U
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- blade
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- fatigue
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- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
The utility model discloses a fatigue test device of engine blade, including vibration test platform (3), vibration test platform (3) are connected with power amplifier (2) a passing signal line, power amplifier (2) passing signal line is connected with one signal generator (1), the top fixedly connected with of vibration test platform (3) enlargies frock (4), amplify the top fixedly connected with centre gripping frock (5) of frock (4), the left end fixed connection of centre gripping frock (5) need carry out vibration fatigue test blade (6). The utility model discloses can guarantee high -quality, accomplish under blade vibration fatigue test's the circumstances effectively, reduce the load of the vibration test platform that has, guarantee the normal work of vibration test director's time and be difficult to break down, showing the life who lengthen the vibration test platform, and then fatigue test's cost is vibrated in the reduction to the engine blade.
Description
Technical field
The utility model is related to fatigue test technology field, the fatigue test dress of more particularly to a kind of engine blade
Put.
Background technology
At present, fatigue experimental device is stress or the strain for sample or component is born cycle or change at random, to determine
The device of the index such as fatigue limit and fatigue life.Before product comes into operation, need to carry out sufficient fatigue in the lab
Performance test is examined, and fatigue limit and the fatigue life of product is measured, so as to ensure that product will not go out in actual use
Existing fatigue damage failure.
For the engine blade that the fields such as aviation and navigation use, it is one of part of most critical in correlation engine.
Because the vibrating fatigue of blade fails, it is likely to result in engine and occurs trouble of shutdown in the process of running, sometimes possibly even
The accident of menace level is caused, jeopardizes the great personal safety as well as the property safety of people.Therefore, correlation engine development and be manufactured into
In the shape stage, by carrying out the vibration fatigue test of engine blade, various defects of the blade in design and manufacture are found out, be
It is very necessary and significant.
At present, the object of the fatigue test of engine blade is generally individual blade or integral wheel, for existing
Engine blade vibration fatigue test device, its often only connection blade and shake table effect, amplify swash
The effect encouraged.Because the vibration test number of times of fatigue test is generally 107Magnitude, the engine relatively low for first-order flexure frequency
Blade, it is meant that test period can be long, therefore, shake table can be in larger working under load longer time, so as to hold
Easily break down, significantly increase the cost that vibration fatigue test is carried out to engine blade.
Therefore, at present in the urgent need to developing a kind of fatigue experimental device, it can reduce the negative of had shake table
Lotus, it is ensured that shake table long-time normal work and be not easy break down, significantly extend the service life of shake table, enter
And reduce the cost that vibration fatigue test is carried out to engine blade.
Utility model content
In view of this, the purpose of this utility model is to provide a kind of fatigue experimental device of engine blade, and it can be
Ensure it is high-quality, effectively complete vibration fatigue test of blade in the case of, reduce the load of had vibration mechine, can be with
Ensure vibration mechine long-time normal work and be not easy to break down, significantly extend the service life of vibration mechine,
And then the cost that vibration fatigue test is carried out to engine blade is reduced, and it is easy to operate, be conducive to extensive production
Using being of great practical significance.
Therefore, the utility model provides a kind of fatigue experimental device of engine blade, including vibration mechine, it is described
Vibration mechine is connected with a power amplifier by holding wire, and the power amplifier passes through holding wire and a signal
Generator is connected；
Amplification frock is fixedly connected with the top of the vibration mechine, folder is fixedly connected with the top of the amplification frock
Frock is held, the left end of the clamping tooling is fixedly connected the blade for needing to carry out vibration fatigue test.
Wherein, the top right-hand member of the vibration mechine and the top center of the clamping tooling are both provided with accelerating
Degree sensor.
Wherein, foil gauge is provided with the crown center position of the blade, the left part of the blade has blade tip, institute
That states blade tip is arranged above a laser displacement sensor.
Wherein, the acceleration transducer, foil gauge and laser displacement sensor pass through a holding wire and one respectively
Data collecting instrument is connected, and the data collecting instrument is connected with a computer.
Wherein, the amplification frock includes pedestal, two adjusting sliders and amplifies beam, and the wherein bottom of pedestal passes through screw
It is connected with the top of vibration mechine, it is described to amplify the top that beam bottom or so two ends are installed on pedestal by two adjusting sliders
Portion, the amplification beam is connected with the clamping tooling.
The technical scheme provided from above the utility model, compared with prior art, the utility model proposes
A kind of fatigue experimental device of engine blade, it can ensure feelings that are high-quality, effectively completing vibration fatigue test of blade
Under condition, the load of had vibration mechine is reduced, it is ensured that vibration mechine long-time normal work and be not easy
Existing failure, significantly extends the service life of vibration mechine, and then reduction carries out vibration fatigue test to engine blade
Cost, it is easy to operate, be conducive to extensive production application, it is of great practical significance.
Brief description of the drawings
A kind of structure schematic diagram of the fatigue experimental device of engine blade that Fig. 1 is provided for the utility model；
Amplify frock and vibration test in a kind of fatigue experimental device of engine blade that Fig. 2 is provided for the utility model
Attachment structure between platform, clamping tooling and blade amplifies simplified schematic diagram；
In figure, 1 is signal generator, and 2 is power amplifier, and 3 is vibration mechine, and 4 to amplify frock, and 5 is clamping work
Dress, 6 is blade, and 7 is acceleration transducer, and 8 is foil gauge, and 9 is laser displacement sensor, and 10 is data collecting instrument, and 11 is meter
Calculation machine, 41 is pedestal, and 42 is adjusting slider, and 43 is amplification beam.
Specific embodiment
In order that those skilled in the art more fully understand the utility model scheme, below in conjunction with the accompanying drawings and implementation method
The utility model is described in further detail.
A kind of structure schematic diagram of the fatigue experimental device of engine blade that Fig. 1 is provided for the utility model.
The fatigue experimental device of a kind of engine blade provided referring to Fig. 1, the utility model, for engine blade
Carry out vibration fatigue test.The fatigue experimental device specifically includes vibration mechine 3, the vibration mechine 3 and a power
Amplifier 2 is connected by holding wire, and the power amplifier 2 is connected by holding wire with a signal generator 1；
The top of the vibration mechine 3 is fixedly connected with amplification frock 4, and the top for amplifying frock 4 is fixedly connected
There is clamping tooling 5, the left end of the clamping tooling 5 is fixedly connected the blade 6 for needing to carry out vibration fatigue test.
In the utility model, implement, the clamping tooling 5 can be connected with the blade 6 by clamping, screw thread
The various ways such as connect to be fixedly connected.
For the utility model, it is necessary to illustrate, the signal generator 1 is used to export the electricity of predeterminated frequency and amplitude
Pressure signal is to power amplifier 2；The power amplifier 2 is used to receive the voltage signal that the signal generator 1 is sent
Afterwards, exported after amplification and give the vibration mechine 3 (being that is exaggerated the power output of the signal generator 1), so that
The vibration mechine 3 is driven to run.Therefore, the signal generator 1 can control vibration test by power amplifier 2
The excited frequency and exciting force size of platform 3.
Also, it should be noted that vibration mechine is for the conventional examination in experiment lab simulation indeed vibrations environmental effect
Test equipment.The vibration mechine 3 is for by default frequency and exciting acceleration, (first-order flexure of preferably blade to be intrinsic
Vibration frequency and corresponding exciting acceleration), exciting (i.e. excited vibration) is carried out to blade after amplifying the amplification of frock 4.
In the utility model, implement, the vibration mechine 3 is preferably capable providing the vibration of sinusoidal thrust
Testing stand, the sinusoidal excitation frequency that it has is 2~4000Hz (need to cover test frequency), and its sinusoidal thrust is not less than 1T.
In the utility model, described amplification after frock 4 is used for the excitation amplification for exporting the vibration mechine 3 is transmitted
To clamping tooling 5, because clamping tooling 5 connects the blade 6, therefore the excitation after amplification also passed into the blade 6.
Implement, the frock 4 of amplifying can preferably adjust the structure of amplification of frequency ranges, and it has regulation energy
Power, can meet the amplification excitation in certain frequency band, the leaf less big so as to meet various first-order flexure intrinsic frequency gaps
The fatigue test demand of piece.
, it is necessary to explanation, shown in Figure 2 in the utility model, the amplification frock 4 is broadly divided into three portions
Point, including 41, two adjusting sliders 42 of pedestal and amplification beam 43, the wherein bottom of pedestal 41 passes through screw and vibration mechine 3
Top be connected, it is described that to amplify beam 43 bottom or so two ends (shown to put by top that two adjusting sliders 42 are installed on pedestal
The left and right two ends of crossbeam 43 can be fixedly connected by screw and slip spiral shell block with adjusting slider 42), it is described to amplify beam 43 and institute
Clamping tooling 5 is stated to be connected (blade is installed on and amplifies on the clamping tooling 5 that is connected of beam), similar to beam with both ends built-in for
The utility model, the purpose of design of the amplification beam is to ensure that its single order corner frequency and the first-order flexure frequency of blade (are tried
Test frequency) it is close, the weight on the other hand amplifying beam is significantly larger than the weight of blade, therefore, when amplification beam and blade occur coupling
After conjunction, will not have an impact to respective intrinsic frequency.When vibration mechine 3 is encouraged with test frequency, amplify itself facing for beam
Near resonance oscillating state, the excitation magnitude for amplifying Liang Chu can be significantly hotter than pedestal, and the output of vibration mechine 3 is amplified so as to reach
The effect of excitation.
On the other hand, the position (i.e. the position of adjusting slider 42) that amplification beam 43 is connected with pedestal 41 can be change
(specifically chute, two adjusting sliders 42 can be opened on the left and right two ends of pedestal 41 by amplifying the waist-shaped hole at the two ends of beam 43
Can be moved left and right in the chute 3), therefore the fixed position at the left and right two ends for amplifying beam 43 can be adjusted, you can to pass through
Change the intrinsic frequency that the relative distance between two adjusting sliders 42 amplifies beam 43 to change.Amplify the intrinsic frequency of beam so as to change
Rate, so that the ability with regulation amplification of frequency ranges.
In the utility model, implement, the top right-hand member of the vibration mechine 3 and the clamping tooling 5
Top center is both provided with acceleration transducer 7, the acceleration transducer 7 on the vibration mechine 3 and clamping tooling 5
It is respectively used to monitor the initial output drive of the vibration mechine 3 and (i.e. described blade is received by the excitation after amplification
Actual excitation), and acceleration signal is exported, it is hereby achieved that amplifying the multiplication factor of frock 4.
In the utility model, foil gauge 8, the left end of the blade 6 are provided with the crown center position of the blade 6
Portion has a blade tip, and the blade tip is arranged above a laser displacement sensor 9；
It should be noted that the foil gauge 8 is arranged at the larger position of surface stress of the blade 6.The strain
Piece 8 is used to monitor vibration strains (stress) grade of the blade when vibration fatigue test is carried out, and exports strain signal；Institute
Laser displacement sensor 9 is stated for monitoring the displacement of the blade tip of the blade 6, and output displacement signal, so as to aid in determining institute
State stress levels of the blade 6 when vibration fatigue test is carried out.
In the utility model, implement, the acceleration transducer 7, foil gauge 8 and laser displacement sensor 9
It is connected with a data collecting instrument 10 by a holding wire respectively, the data collecting instrument 10 is connected with a computer 11
Connect；
Wherein, the data collecting instrument 10 is used for acceleration transducer 7, foil gauge 8 and laser displacement described in real time record
The Monitoring Data (being respectively acceleration signal, strain signal and displacement signal) that sensor 9 is exported respectively after monitoring, and be transmitted to
The computer 11；
In the utility model, implement, the data collecting instrument 10 can be Jiangsu Stettlen electronic equipment system
Make the data collecting instrument of the model TST5912 of Co., Ltd's manufacture.It is, of course, also possible to be other any one can gather institute
State the data collecting instrument of the Monitoring Data exported after acceleration transducer 7, foil gauge 8 and laser displacement sensor 9 are monitored.
The computer 11 is used to set the acquisition parameter of the data collecting instrument 10, and described in real-time storage and display
The Monitoring Data (including acceleration signal, strain signal and displacement signal) that data collecting instrument 10 sends.
The fatigue experimental device of the engine blade provided based on above-mentioned the utility model, it specifically carries out vibrating fatigue examination
Test, comprise the following steps：
1st, blade 6 is installed on vibration mechine 3 by clamping tooling 5 and amplification frock 4；
2nd, test operation personnel are by tapping blade 6, and (the method obtains testpieces intrinsic frequency to the method encouraged with transient state
A kind of conventional method, transient state excitation, that is, transient impact excitation, that is, encourage and only exist within the very short time period, this
Excitation before and after the section time is all the first-order flexure eigentone for 0) obtaining blade 6；Or carried out by vibration mechine 3
Frequency sweep obtains the first-order flexure eigentone of blade 6 (by analyzing foil gauge 8 and the data of laser displacement sensor 9；
In the utility model, single order that can be directly by data collecting instrument or vibration controller acquisition blade 6 is curved
Bent eigentone.For the utility model, it is necessary to explanation, the frequency sweep is vibration technical term, new in this practicality
In type, the frequency sweep can export one section of amplitude fixed frequency pumping signal from low to high, while monitor making by shake table
It is the response signal (or transmission function of response and excitation) of the engine blade of testpieces, if amplitude on a certain frequency
There is maximum, this frequency is the intrinsic frequency as the engine blade of testpieces).In addition, frequency sweep method and transient state
Method of the advocate approach as intrinsic frequency is obtained, they are all by analyzing strain data (foil gauge 8) and displacement data (laser
Displacement transducer), main method is exactly, by fast Flourier FFT to frequency domain, directly to read these data on frequency domain
The peak value of correlation curve is taken, the corresponding frequency of peak value is exactly resonant frequency.
3rd, regulation amplifies frock 4 to suitable position, its first-order flexure eigentone to blade 6 is played amplification
Effect；
It should be noted that for the utility model, the position of adjusting slider in frock, i.e. regulation being amplified by adjusting and being put
The position of big frock.Seeing basic adjusting method is：Under certain state, if measuring the intrinsic frequency for amplifying amplification beam in frock
Rate is less than Natural Frequency of Blade, then should move inward two adjusting sliders and (reduce and amplify beam or so two ends fixing point this two consolidates
The distance between fixed point), so as to increase the intrinsic frequency for amplifying beam, otherwise two adjusting sliders are then displaced outwardly, increase and amplify
The distance between beam or so two ends fixing points this two fixing point, so as to reduce the intrinsic frequency for amplifying beam.
4th, under small magnitude record blade 6 strain and displacement data, the linear relationship of the displacement of calibration strain, for it
Determine that blade fatigue test stress levels provide foundation and (when the vibration stress generally in blade reaches fatigue strength grade, answer afterwards
Become sector-meeting failure)；
5th, increase excitation, blade 6 continues fatigue test in the case where test frequency is with the vibration amplitude that specifies, until blade 6
First-order flexure eigentone declines 1%, that is, illustrate that blade 6 generates fatigue crack, completes fatigue test；
6th, by data collecting instrument 10 and computer 11, real time record blade 6 is all kinds of during vibration fatigue test
Data, the parameter such as including stress level, vibration frequency, test period.
For the utility model, the object tested by the fatigue experimental device can be individual blade or comprising multiple
The impeller of blade.For the utility model, one end of the blade 6 and vibration mechine 3 are connected, the other end and clamping work
Fill 5 to be connected, wherein clamping tooling 5 is used for fixing blade, the cantilever of blade 6 is fixed on the top for amplifying frock 4.Vibration
Testing stand 5 with the first-order flexure eigentone of blade 6 and corresponding exciting acceleration, by amplifying frock 4 come to blade 6
Exciting is carried out, is made blade 6 and is vibrated with the stress level for specifying under the frequency, until the intrinsic frequency of blade 6 declines 1%
(i.e. explanation generates fatigue crack), so that the vibration fatigue test of complete blade pair 6.In whole vibration fatigue test process
In, by data collecting instrument 10 and computer 11, the test data such as real time record test period, stress level and vibration frequency letter
Breath.
Therefore, the utility model significantly reduces the load of vibration mechine 3, so as to reduce by using frock 4 is amplified
The fault rate of equipment, while reducing energy consumption.Further, since the configuration for amplifying frock 4 is adjustable, therefore the utility model can be fitted
Blade for being more or less the same to various intrinsic frequencies carries out vibration fatigue test.
In sum, compared with prior art, the fatigue test dress of a kind of engine blade that the utility model is provided
Put, its can ensure it is high-quality, effectively complete vibration fatigue test of blade in the case of, reduce had vibration mechine
Load, it is ensured that vibration mechine long-time normal work and be not easy break down, significantly extend vibration mechine
Service life, and then reduce the cost of vibration fatigue test carried out to engine blade, it is easy to operate, be conducive to
Extensive production application, is of great practical significance.
The above is only preferred embodiment of the present utility model, it is noted that for the common skill of the art
For art personnel, on the premise of the utility model principle is not departed from, some improvements and modifications can also be made, these improve and
Retouching also should be regarded as protection domain of the present utility model.
Claims (5)
1. a kind of fatigue experimental device of engine blade, it is characterised in that including vibration mechine (3), the vibration test
Platform (3) is connected with a power amplifier (2) by holding wire, and the power amplifier (2) is believed by holding wire and one
Number generator (1) is connected；
Amplification frock (4) is fixedly connected with the top of the vibration mechine (3), the top for amplifying frock (4) is fixed and connected
Clamping tooling (5) is connected to, the left end of the clamping tooling (5) is fixedly connected the blade (6) for needing to carry out vibration fatigue test.
2. fatigue experimental device as claimed in claim 1, it is characterised in that the top right-hand member of the vibration mechine (3) and
The top center of the clamping tooling (5) is both provided with acceleration transducer (7).
3. fatigue experimental device as claimed in claim 2, it is characterised in that set on the crown center position of the blade (6)
It is equipped with foil gauge (8), the left part of the blade (6) has a blade tip, the blade tip is arranged above a laser displacement
Sensor (9).
4. fatigue experimental device as claimed in claim 3, it is characterised in that the acceleration transducer (7), foil gauge (8)
It is connected with a data collecting instrument (10) by a holding wire respectively with laser displacement sensor (9), the data acquisition
Instrument (10) is connected with a computer (11).
5. fatigue experimental device as claimed in claim 1, it is characterised in that the amplification frock (4) includes pedestal (41), two
Individual adjusting slider (42) and amplification beam (43), the wherein bottom of pedestal (41) are by screw and the top phase of vibration mechine (3)
Even, beam (43) bottom or so the two ends of amplifying pass through the top that two adjusting sliders (42) are installed on pedestal (41), described to put
Crossbeam (43) is connected with the clamping tooling (5).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621063217.8U CN206177542U (en) | 2016-09-20 | 2016-09-20 | Fatigue test device of engine blade |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621063217.8U CN206177542U (en) | 2016-09-20 | 2016-09-20 | Fatigue test device of engine blade |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206177542U true CN206177542U (en) | 2017-05-17 |
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ID=58676319
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201621063217.8U Active CN206177542U (en) | 2016-09-20 | 2016-09-20 | Fatigue test device of engine blade |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106441761A (en) * | 2016-09-20 | 2017-02-22 | 天津航天瑞莱科技有限公司 | Engine blade fatigue testing device |
| CN107917786A (en) * | 2017-11-20 | 2018-04-17 | 广西科技大学 | A kind of method of automobile exhaust pipe vibration experiment |
| CN108240896A (en) * | 2018-04-18 | 2018-07-03 | 西南交通大学 | Fatigue strength measuring method and device |
| CN108871717A (en) * | 2018-09-13 | 2018-11-23 | 广西科技大学 | Elliposoidal package clamp for vibration test |
| CN108918070A (en) * | 2018-08-28 | 2018-11-30 | 苏州长菱测试技术有限公司 | A kind of vibration fatigue test device for high frequency stress blade |
| CN109323853A (en) * | 2018-09-29 | 2019-02-12 | 浙江中烟工业有限责任公司 | A kind of blower leaf fan vibration detection device and fault detection prediction technique |
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2016
- 2016-09-20 CN CN201621063217.8U patent/CN206177542U/en active Active
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106441761A (en) * | 2016-09-20 | 2017-02-22 | 天津航天瑞莱科技有限公司 | Engine blade fatigue testing device |
| CN107917786A (en) * | 2017-11-20 | 2018-04-17 | 广西科技大学 | A kind of method of automobile exhaust pipe vibration experiment |
| CN108240896A (en) * | 2018-04-18 | 2018-07-03 | 西南交通大学 | Fatigue strength measuring method and device |
| CN108918070A (en) * | 2018-08-28 | 2018-11-30 | 苏州长菱测试技术有限公司 | A kind of vibration fatigue test device for high frequency stress blade |
| CN108871717A (en) * | 2018-09-13 | 2018-11-23 | 广西科技大学 | Elliposoidal package clamp for vibration test |
| CN108871717B (en) * | 2018-09-13 | 2023-06-16 | 广西科技大学 | Clamp for vibration test of ellipsoidal package |
| CN109323853A (en) * | 2018-09-29 | 2019-02-12 | 浙江中烟工业有限责任公司 | A kind of blower leaf fan vibration detection device and fault detection prediction technique |
| CN109323853B (en) * | 2018-09-29 | 2020-06-30 | 浙江中烟工业有限责任公司 | Fan blade fan vibration detection device and fault detection prediction method |
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