The utility model content
The utility model is at the shortcoming of above-mentioned prior art, provide a kind of and can detect the diagnosis high-temperature high pressure valve, detect real-time, highly sensitive, detect diagnostic result accurately and reliably, simple to operation, security good, the high-temperature high pressure valve leakage failure diagnostic device that detects based on acoustic emission signal of simple in structure, long service life.
In order to solve the problems of the technologies described above, the technical solution adopted in the utility model is: a kind of high-temperature high pressure valve leakage failure diagnostic device that detects based on acoustic emission signal, it comprises the signal difference processing unit, processing unit and be fixedly arranged on two acoustic emission signal sensors of valve body on the suction side and outlet side respectively, described acoustic emission signal sensor links to each other with processing unit by the signal difference processing unit, described two acoustic emission signal sensors detect the acoustic emission signal of valve body on the suction side and outlet side respectively and export the signal difference processing unit to, described signal difference processing unit obtain the output of two acoustic emission signal sensors acoustic emission signal difference and export processing unit to, described processing unit obtains the slip of valve body and exports corresponding valve leak fault diagnosis result according to described slip according to the difference of acoustic emission signal.
As further improvement of the utility model:
Described acoustic emission signal sensor is supported on the valve body by waveguide rod;
Described two acoustic emission signal sensors are that the center is symmetrical distribution with the valve body;
Described acoustic emission signal sensor links to each other with the signal difference processing unit by the pre-process unit, and described pre-process unit amplifies, exports the signal difference processing unit to after the filtering the acoustic emission signal that the acoustic emission signal sensor is exported;
Described pre-process unit links to each other with the signal difference processing unit by the A/D converting unit, and described A/D converting unit carries out the acoustic emission signal of pre-process unit output to export the signal difference processing unit to after windowing process, the analog to digital conversion;
Described signal difference processing unit links to each other with processing unit by the digital filtering unit, and described digital filtering unit carries out the difference of the acoustic emission signal of signal difference processing unit output to export processing unit to after the filtering;
Described processing unit links to each other with the diagnosis output unit, and described diagnosis output unit is exported the valve leak fault diagnosis result of processing unit output with the form of sound or image or sound and image combination.
The utlity model has following advantage: the utility model obtains the acoustic emission signal difference of valve body on the suction side and outlet side by the signal difference processing unit, processing unit calculates the slip of valve body and exports corresponding valve leak fault diagnosis result according to described slip according to the difference of acoustic emission signal, can in time diagnose the discovery leakage valve, significantly reduce the economic loss that valve leak causes, improve the security that valve uses, have and detect in real time, highly sensitive, detect diagnostic result accurately and reliably, simple to operation, security is good, simple in structure, the advantage of long service life.The acoustic emission signal sensor is supported on the valve body by waveguide rod, does not therefore influence the structure of valve, can detect the high-temperature high pressure valve that diagnosis is difficult to even can't be approaching, has improved the security that detects diagnosis greatly; Two acoustic emission signal sensors are that the center is symmetrical distribution with the valve body, and therefore the correlativity of two acoustic emission signal sensors is better, and the difference that can more accurately pass through acoustic emission signal obtains the valve leak fault diagnosis result; The pre-process unit to acoustic emission signal amplify, filtering, the digital filtering unit carries out filtering to the difference of acoustic emission signal, noise still less, signal is more accurate, thereby can improve detection sensitivity; The diagnosis output unit can be exported diagnostic result in a variety of forms, and convenient operating personnel in time obtain diagnostic result, so that the economic loss that valve leak brings is in time handled, reduced to leakage valve.
Embodiment
As depicted in figs. 1 and 2, the high-temperature high pressure valve leakage failure diagnostic device that detects based on acoustic emission signal in the present embodiment comprises signal difference processing unit 4, processing unit 6 and be fixedly arranged on two acoustic emission signal sensors 1 of valve body 9 on the suction sides and outlet side respectively, acoustic emission signal sensor 1 links to each other with processing unit 6 by signal difference processing unit 4, two acoustic emission signal sensors 1 detect the acoustic emission signal of valve body 9 on the suction sides and outlet side respectively and export signal difference processing unit 4 to, signal difference processing unit 4 obtain two acoustic emission signal sensors 1 output acoustic emission signal difference and export processing unit 6 to, processing unit 6 obtains the slip of valve body 9 and exports corresponding valve leak fault diagnosis result according to slip according to the difference of acoustic emission signal.
In the present embodiment, valve body 9 is a high-temperature high pressure valve, its temperature is about 300~550 ℃, acoustic emission signal sensor 1 is supported on the valve body 9 by waveguide rod 8, waveguide rod 8 is welded on the shell of valve body 9, and acoustic emission signal sensor 1 adopts the attached mode of magnetic to be fixed on the waveguide rod 8, and waveguide rod 8 adopts the 10# steel to make, therefore waveguide rod 8 both can effectively have been transmitted the acoustic emission signal of stress wave form, can prevent that again the high temperature transmission of valve body 9 from damaging acoustic emission signal sensor 1.In addition, also can adopt other modes that acoustic emission signal sensor 1 is fixed on the valve body 9.
In the present embodiment, two acoustic emission signal sensors 1 are that the center is symmetrical distribution with valve body 9.Therefore, the acoustic emission signal sensor 1 of both sides, valve body 9 front and back is highly identical, identical to the distance between the spool of valve body 9, two acoustic emission signal sensor 1 models are identical in addition, make that the correlativity of two acoustic emission signal sensors is better, can more accurately obtain the leakage failure diagnostic result of valve by the difference of acoustic emission signal.
Acoustic emission signal sensor 1 links to each other with signal difference processing unit 4 by pre-process unit 2, and the acoustic emission signal that 2 pairs of acoustic emission signal sensors in pre-process unit 1 are exported is amplified, export signal difference processing unit 4 to after the filtering.Pre-process unit 2 links to each other with signal difference processing unit 4 by A/D converting unit 3, and A/D converting unit 3 carries out the acoustic emission signal of pre-process unit 2 outputs to export signal difference processing unit 4 to after windowing process, the analog to digital conversion.Signal difference processing unit 4 links to each other with processing unit 6 by digital filtering unit 5, and digital filtering unit 5 carries out the difference of the acoustic emission signal of signal difference processing unit 4 outputs to export processing unit 6 to after the filtering.Processing unit 6 links to each other with diagnosis output unit 7, and diagnosis output unit 7 is exported the valve leak fault diagnosis result of processing unit 6 outputs with the form of sound or image or sound and image combination.
The model of acoustic emission signal sensor 1 is R15 α in the present embodiment, and its output signal is an analog voltage signal, and its responding range is 50~400kHz, resonant frequency 150kHz, and peak response is 69dB.Pre-process unit 2 is the amplification filtering circuit.A/D converting unit 3 adopts the acoustic emission signal capture card to realize, the PCI6110 acoustic emission signal capture card that acoustic emission signal capture card in the present embodiment adopts NI company to produce, the acoustic emission signal capture card is 2 passage 40MHz, 18 A/D, dynamic translation scope greater than 85dB can directly be provided, and its frequency range is 1k~3MHz.Signal difference processing unit 4, digital filtering unit 5, processing unit 6 pass through computer realization.Diagnosis output unit 7 is the display of computing machine, and the valve leak fault diagnosis result of processing unit 6 outputs is exported to operating personnel with the form of image.
As shown in Figure 3, present embodiment is as follows to the treatment scheme of the acoustic emission signal of acoustic emission signal sensor 1 output:
1) acoustic emission signal of 2 pairs of acoustic emission signal sensors in pre-process unit 1 output amplify, filtering;
2) 3 pairs of acoustic emission signals of A/D converting unit are carried out windowing process, obtain the sampling fragment of acoustic emission signal, and the acoustic emission signal sampling fragment that obtains is carried out analog to digital conversion;
3) the voltage sampling fragment of the acoustic emission signal of 4 pairs of two A/D converting units of signal difference processing unit, 3 outputs is got difference;
4) difference of the acoustic emission signal of the 5 pairs of digital forms in digital filtering unit is carried out digital filtering, obtains the difference of filtered acoustic emission signal;
5) processing unit 6 obtains the difference of acoustic emission signal, and carries out the difference signal mean square value of unit of account in the time according to the difference of the acoustic emission signal that obtains, and goes out slip according to the difference signal mean-square calculation.Difference signal mean square value wherein
Function be:
In the formula (1), N represents the sampling number of processing unit 6 in the unit interval, x[n] expression sampled point magnitude of voltage.
Under the constant situation of valve mechanism and fluid parameter, several leak the mean square value of the acoustic emission signal of operating modes by the experimental measurement valve
The slip that the correspondence of operating mode is leaked in these tests is Q
1, Q
2, Q
3....Utilize the test figure of above-mentioned operating mode, can obtain the root-mean-square value AE of valve leak rate Q and difference signal
RMSRegression equation be:
To a certain actual detected operating mode, with the difference signal mean square value
Root-mean-square value AE
RMSSubstitution formula (2) can obtain the valve volume slip Q of this operating mode, in general, gets first three rank of equation and can satisfy the accuracy of detection requirement.
6) processing unit 6 carries out the leakage failure diagnosis according to the slip that step 5) obtains to high-temperature high pressure valve, diagnosis output unit 7 output diagnostic results.Because application, application places and the present position of high-temperature high pressure valve and the difference of effect; so the leakage standard of shutdown maintenance or replacing valve is also different: when tested valve does not allow leakage; in case it is non-vanishing to record slip; processing unit 6 is reported to the police to diagnosis output unit 7 output reds; prompting needs repairing or changes valve; otherwise diagnosis output unit 7 shows that valve does not have the prompting of leakage.When tested valve allows a certain amount of leakage, system judges which kind of leakage class is this slip be in: when slip is less than or equal to the maximum permission of JB/T9092-1999 valve leakage rate examination criteria value, processing unit 6 is reported to the police to diagnosis output unit 7 output blues, and prompting has leakage but is in the valve permission leakage scope; When slip meets or exceeds half that set to allow leakage rate but still less than setting when allowing leakage rate, processing unit 6 points out this valve leak situation to arouse attention to diagnosis output unit 7 output yellow alarm, need carry out maintenance or change and prepare; When slip met or exceeded setting permission leakage rate, processing unit 6 was reported to the police to diagnosis output unit 7 output reds, and this valve need be keeped in repair at once or change to prompting.
Below only be preferred implementation of the present utility model, protection domain of the present utility model also not only is confined to the foregoing description, and all technical schemes that belongs under the utility model thinking all belong to protection domain of the present utility model.Should be pointed out that for those skilled in the art in the some improvements and modifications that do not break away under the utility model principle prerequisite, these improvements and modifications also should be considered as protection domain of the present utility model.