Background technology
Safety valve is the widely used safety guard of bearing device, and its functional reliability is for ensureing that the long period safe operation of production system has great importance.Sealing is one of important performance parameter of safety valve, explicitly calls for that safety valve checks before type approval test, factory inspection, installation, all should carry out leakage test in periodic check in " safety valve safety and technical supervision code ", current China take gas as the safety valve leakage test work of medium is come according to the regulation of " safety valve safety and technical supervision code ", according to the pilot system of recommending in code annex, need when every safety valve test blanking cover is installed, connect collection fistulae and water tumbler, need be detected by an unaided eye during inspection at least two pieces of tensimeters, and count leakage number of bubbles per minute with stopwatch manual time-keeping, compare leaking number of bubbles from maximum permission slip under the different set-pressure value given by table 12 in GBT12243-2005 " slips of air or other gas safety valve leakage tests " and different safety valve flow diameter again, and then judge that whether qualified the sealing of safety valve is.This test system architecture is complicated, relies on testing crew manual operation and judgement completely, and human factor is large, and not only test operation process is loaded down with trivial details, inefficiency, and the accuracy judged and poor reliability.
The patent document of " a kind of method of calibration of safety valve sealing property " (publication No. CN103808474A) discloses a kind of method of calibration to safety valve sealing property, the slip that the method adopts pressure over time drop-out value or pressure drop percentage to represent is as the Judging index of safety valve leakage test, but this index does not have the support of national standard, not there is cogency and operability, be not easy to apply; And leakage rate is relevant with the useful volume of Pressure Drop and tested safety valve, direct corresponding relation is not had with sealing load, if ignore the impact of tested safety valve useful volume, so pressure over time drop-out value or decline percentage truly certainly will can not reflect slip.
The patent document of " automatic calibrating instrument for safety valve " (publication number CN1776387A) discloses a kind of intelligentized testing device of safety valve, pressure unit is configured with in device, data acquisition unit, data processor, display, it can realize safety valve Automatic-clamping in checking procedure, pressurization, calibration of set-pressure and pressure release, and computer management function is provided, but this calibration equipment can only carry out wherein one in safety valve testing project, the i.e. intelligent checking of set-pressure, leakage test project only possesses the function of adjustment pressure to this initial link of sealing load, and leakage test process can only have been come by man-made chamber traditional in " safety valve safety and technical supervision code " with judgement.
Summary of the invention
The object of the present invention is to provide a kind of Intelligent safe valve seal pilot system, this pilot system can carry out intelligentized test to the sealing property of safety valve quickly and easily, human factor in Elimination test process, improves accuracy and the reliability of test findings.
The technical solution adopted for the present invention to solve the technical problems is:
A kind of Intelligent safe valve seal pilot system, comprise computer system, data acquisition unit and be located at the pressure unit on test connecting pipeline, pressure unit, data acquisition unit and computer system successively communication are connected, the data in described computer system stores " GB/T12243-2005 spring loaded safe valve national standard " table 12, seal test pressure retention time and leak test time are set by computer system, pressure value P before the test of record pressure unit feedback1with pressure value P after test2, computer system is according to formula N=(P1-P2) VNmax/tP0vmax calculates leakage number of bubbles per minute, and per minute maximumly allow to leak number of bubbles by what specify in the leakage number of bubbles per minute calculated and table 12 and contrast, judge that whether the sealing property of safety valve is qualified, judgment result displays on the computer systems the most at last, in formula, N is leakage number of bubbles per minute, V is test useful volume, Nmax is that number of bubbles is leaked in the per minute maximum permission of regulation in " GB/T12243-2005 spring loaded safe valve national standard " table 12, Vmax is the per minute maximum permission leakage volume corresponding with Nmax, P0for standard atmospheric pressure.
Further, described computer system is also equipped with the man-machine interface of safety valve test data inputting, display, inquiry and printing; Described safety valve test data are stored in safety valve database and call for computer system.
The invention has the beneficial effects as follows: without the need to installing closure plate to safety valve, connecting Ji Louguanlu and water tumbler when one, testing, simplify experiment process, be easy to operation, efficiency is high; Two, without the need to people's number bubble, eliminating human factor, is completed reading and the data processing of force value, automatic decision test findings by computer system, and efficiency is high, saving manpower; Three, formula is utilized the voltage drop value of unit interval safety valve to be converted to the slip represented with leakage number of bubbles per minute, and per minute maximumly allow to leak number of bubbles by what specify in this leakage number of bubbles and " GB/T12243-2005 spring loaded safe valve national standard " table 12 and compare, and then judge that whether the sealing property of safety valve is qualified, improve accuracy and the reliability of test findings; Four, native system possesses set-pressure adjustment and experiments of sealing performance dual-use function simultaneously.
Embodiment
As shown in Figure 1, the invention provides a kind of Intelligent safe valve seal pilot system, tested safety valve 5 is located on test-bed 4, the test pipe 6 be communicated with tested safety valve 5 is provided with source of the gas valve 1, test chamber 2, pet valve 3, pointer tensimeter 7 and bleeder valve 9, the front end of tested safety valve 5 is located at successively by source of the gas valve 1, test chamber 2 and pet valve 3, and pointer tensimeter 7 and bleeder valve 9 are located at the rear end of tested safety valve 5 successively; The pressure unit 8 that described leakage test system also comprises computer system 11, data acquisition unit 10 and is located on test pipe 6, pressure unit 8 is positioned at the rear end of tested safety valve 5, and pressure unit 8, data acquisition unit 10 are connected with computer system 11 successively communication.Pressure unit 8 in real time detection experiment time pressure, and by data acquisition unit 10, force value is fed back to computer system 11.DMP331 type high precision intelligent pressure transmitter selected by pressure unit, can select 0 ~ 1.6MPa, 0 ~ 4.0MPa, 0 ~ 10.0MPa, 0 ~ 16.0MPa and 0 ~ 60.0MPa five kinds of ranges as required, accuracy selection 0.05%FSOBFSL; Data acquisition unit 10 adopts Yanhua ADAM-4017 module; Computer system 11 adopts HP180DTPCSenes microcomputer; Computer system 11 and data acquisition unit 10 use RS485 serial port communication.
Data in computer system 11 stores " GB/T12243-2005 spring loaded safe valve national standard " table 12, computer system 11 is also equipped with the man-machine interface of safety valve test data inputting, display, inquiry and printing, shown in concrete composition graphs 2, the interface of described man-machine interface adopts Fameview to carry out configuration, comprise " verification task window ", carry out by " verification task window " user the input verifying pressure, flow diameter and test useful volume, and verification force value is shown and clear operation; " verification passage indication window ", is shown by " verification passage indication window " computer system verification passage to 0 ~ 1.6MPa, 0 ~ 4.0MPa, 0 ~ 10.0MPa, 0 ~ 16.0MPa and 0 ~ 60.0MPa five kinds of ranges; " calibration of set-pressure window ", can be carried out the instruction input tested and reset, and show test result, test result mean value and acceptance value term of reference by " calibration of set-pressure window " user; " leakage test window ", beginning when can carry out leakage test by " leakage test window " user and reset instruction input, the input of pressure hold time and leak test time, the real time value display of leakage number of bubbles per minute, test pressure, system pressure drop, Pressure Drop per minute, and represent the instruction whether sealing property is qualified; The interface of described man-machine interface also comprises " Report Parameters fills in menu ", " test data sheet menu ", " reporting printing menu ", " the inquiry of historical data menu ", " operation instruction menu " and " LoginLogout menu ".Inside computer system is also provided with the safety valve database for storage security valve test figure, and computer system is called according to needing during test the data of database or stored.
Shown in composition graphs 3, carry out according to the following step during test:
A) be fixed on test-bed 4 by tested safety valve 5, start-up simulation machine system 11, enters man-machine interface;
B) call " LoginLogout menu ", carry out operating personnel's login, namely enter pilot system after being proved to be successful, as needed blocked operation user, then again log in after nullifying, computer system shows according to log-on message and records operator's information;
C) call " the inquiry of historical data menu ", " Report Parameters fills in menu ", " inspection record menu ", " operation instruction menu " according to the needs of test, carry out inquiry and the input of safety valve correlation test data;
D) by " verification task window " input validation pressure, flow diameter and test useful volume;
F) computer system 11 is according to the verification pressure of input, selects the verification passage of a kind of pressure unit in 0 ~ 1.6MPa, 0 ~ 4.0MPa, 0 ~ 10.0MPa, 0 ~ 16.0MPa and 0 ~ 60.0MPa five kinds of ranges, and shows the range passage selected;
G) close pet valve 3 and bleeder valve 9, open source of the gas valve 1, then manual unlocking regulates pet valve 3, makes test gas enter tested pet valve 5, controls pumping rate, makes speed be not more than 0.01MPa/s; After pumping rate is stable, activate test instruction by " calibration of set-pressure window ", observe pressure increase situation simultaneously, when pressure durations rises to set-pressure, the action of tested safety valve 5, pressure stops rising; Computer system 11 is record set-pressure value automatically; Then close pet valve 3, open bleeder valve 9, relief pressure, complete a calibration of set-pressure.Repeat step g twice, computer system 11 is averaged to three set-pressure values, using mean value as final calibration of set-pressure result;
H) close bleeder valve 9, manual adjustments pet valve 3, after the seal test pressure specify pressure adjusting to " safety valve safety and technical supervision code ", close pet valve 3, at " leakage test window ", according to the seal test pressure retention time needed for " safety valve safety and technical supervision code " regulation input test and leak test time, then sign on is activated, enter the countdown of seal test pressure retention time, the test pressure retention time to be sealed terminates automatically to enter the countdown of leak test time afterwards, the countdown of leak test time start and at the end of pointer tensimeter 7 and pressure unit 8 synchro measure leakage test detect before and after force value, for reducing the impact of pilot system fluctuation, computer system takes multi-point average method to obtain testing front pressure value P1with pressure value P after test2,
I) computer system 11 is according to formula N=(P1-P2) VNmax/tP0vmax calculates leakage number of bubbles per minute automatically, and formulation process is as follows:
According to Clapyron Equation PV=mRT/M=nRT(1), can draw
P1V=n1RT（2）；
P2V=n2RT（3）；
P0V0=(n1-n2)RT=(P1V/RT-P2V/RT)RT=(P1-P2)V（4）；
In formula (1), P is gas pressure intensity, and V is test useful volume, and n is the amount of substance of gas, and R is gas constant, and T is absolute temperature; N in formula (2)1for testing the amount of substance of front gas; N in formula (3)2for testing the amount of substance of rear gas; P in formula (4)0for standard atmospheric pressure, V0for gas leakage volume in test;
Thus, Δ V=V0/ t (5), in formula (5), Δ V represents quantity of gas leakage per minute;
Δ P=(P1-P2)/t(6), the gas pressure drop of Δ P representation unit time in formula (6);
Bring formula (4) and formula (5) into formula (6), draw Δ P=P0Δ V/V(7);
Suppose that leakage number of bubbles per minute is N, single isolated bubbles volume is V1, so
ΔP=P0ΔV/V=P0NV1/V（8），
Because the maximum permissible value Vmax and the maximum permission corresponding with Vmax that define each shelves set-pressure and Δ V under flow diameter in " GB/T12243-2005 spring loaded safe valve national standard " table 12 leak number of bubbles Nmax,
Thus V1=Vmax/Nmax(9),
Formula (9) is brought into the corresponding relation that formula (8) namely draws the Leakage Gas Pressure Drop Δ P of leakage number of bubbles N per minute and unit interval: N=Δ PVNmax/tP0vmax=(P1-P2) VNmax/tP0vmax(10);
By the P obtained in step h1, P2with t, Nmax and the Vmax checked in table 12 and P0bring formula (10) into V and namely calculate leakage number of bubbles N per minute;
J) per minute maximumly allow to leak number of bubbles by what specify in the leakage number of bubbles N per minute calculated and described table 12 and contrast, judge that whether the sealing property of safety valve is qualified; If N is not more than Nmax, so safety valve sealing property is qualified, if N is greater than Nmax, so safety valve sealing property is defective;
K) " leakage test window " shows safety valve experiments of sealing performance result, and available green represents qualified, represents defective by redness;
L) open bleeder valve 9 relief pressure, complete this safety valve experiments of sealing performance.Safety valve data in process of the test are stored in safety valve database, and operating personnel can call " reporting printing menu " and print generation print data.
The present invention has following advantage: without the need to installing closure plate to safety valve, connecting Ji Louguanlu and water tumbler when one, testing, simplify experiment process, be easy to operation, efficiency is high; Two, without the need to people's number bubble, eliminating human factor, is completed reading and the data processing of force value, automatic decision test findings by computer system, and efficiency is high, saving manpower; Three, formula is utilized the voltage drop value of unit interval safety valve to be converted to the slip represented with leakage number of bubbles per minute, and per minute maximumly allow to leak number of bubbles by what specify in this leakage number of bubbles and " GB/T12243-2005 spring loaded safe valve national standard " table 12 and compare, and then judge that whether the sealing property of safety valve is qualified, improve accuracy and the reliability of test findings; Four, native system possesses set-pressure adjustment and experiments of sealing performance dual-use function simultaneously.
The above is only preferred embodiment of the present invention, not does any pro forma restriction to the present invention; Any those of ordinary skill in the art, do not departing under technical solution of the present invention ambit, the Method and Technology content of above-mentioned announcement all can be utilized to make many possible variations and modification to technical solution of the present invention, or be revised as the Equivalent embodiments of equivalent variations.Therefore, every content not departing from technical solution of the present invention, according to technical spirit of the present invention to any simple modification made for any of the above embodiments, equivalent replacement, equivalence change and modification, all still belongs in the scope of technical solution of the present invention protection.