Method and device that the oil whip On-line Fault is eliminated
Technical field
The present invention relates to the method and the device of the oil whip On-line Fault elimination of rotating machinery.Especially, the present invention relates to the relative equilibrium position of online change axle journal in bearing, thereby change the active state of bearing film, that is to say under the constant situation of axoplasm amount to change some controlling methods that loading ability of bearing is eliminated oil whip axle; The present invention also relates to the online quick response device that adds static load especially, can online elimination oil whip fault.
Background technique
The production of petroleum and petrochemical industry unit's industry is that continuity is strong, and high maximization of system complex automaticity produced.Equipment failure is shut down; even have an accident; its cost is very big; and bring serious threat to safety in production; in order to extend manufacture cycle, reduce shut-down (breakdown) mainteance number of times and repair time, utilize the oscillating signal of rotating machinery; diagnose out timely and accurately equipment failure, perhaps online its fault of elimination is very important.
The rotating shaft major part of high-speed rotating machine is supported by the oil film sliding bearing.If design bearing or install improperly, faults such as vibration exceeding the standard or low-frequency vibration component be excessive can appear in rotating machinery, when rotating speed is too high, and system even serious oil whip fault can take place.Sometimes, even oil whip does not take place in system, but because the stability margin of system is lower, in case the external world flow-induced vibration occurs, bumps disturbing factor such as mill, system is easy to take place the unstability fault.Because oil-film force is non-linear, along with the rising of rotating speed and the increase of amount of unbalance, the swirl core of rotor journal come-up makes the stability of rotor-support-foundation system weaken.When rotating machinery vibrating exceeds standard and the low-frequency vibration component is excessive or rotating speed when too high, system's generation oil whip, oil whip tends to cause serious equipment accident at short notice, is the most common failure of large high-speed fluid machinery (as turbocompressor, steam turbine etc.).Generally all be that operating some (section) rotating speed operating mode occurs, be after the steady working condition of operation quite a while, to produce suddenly that its oncoming force is very violent sometimes, moment, amplitude raise suddenly, local oil film breaks very soon, causes axle journal and bearing shell friction, produces strong blare.When in a single day this kind phenomenon appears in unit, operating conditions subsequently is abominable gradually, and making unit be reinstalled or change bearing shell by forced-stopping machine also is to cause bearing or whole the reason that unit destroys sometimes.According to incompletely statistics, over past ten years, adopt the Turbo-generator Set of high temperature and high pressure steam, comprise the big unit of installing from external import, it is that the self oscillations principal mode all is oil whirl or flow-induced vibration fault that axle takes place, thereby has determined the critical role of stability in rotor dynamics is analyzed.
But seeing and the improvement method from existing literature, mainly is the parking reprocessing.No matter be the scraping bearing shell or change oil or increase the supporting absolute altitude, these methods need all to shut down to realize that particularly large enterprise will stop, and influences ordinary production completely, cause very big economic loss.Optimal way is exactly to carry out online elimination oil whip, unit normally moves when not stopping, adjust oily temperature and can reduce vibration, but, should not significantly adjust owing to be subjected to the restriction of factors such as oil cooler heat exchange area, cooling water temperature and bearing bush temperature.And the method for other online elimination oil whip yet there are no report.
Summary of the invention
Goal of the invention of the present invention is to provide a kind of method of online elimination oil whip fault, is divided into following steps: detector detects the vibration of rotating machinery, they is transformed into oscillating signal, and sends oscillating signal to controller; The oscillating signal that controller receives and analysis is come out from detector is to determine whether to open electromagnetic actuator device; Actuating device is contactless, by online rotor is applied static action power, changes the static load and the relative equilibrium position of axle journal in bearing of bearing, thereby changes the active state of bearing film to axle, online elimination oil whip fault; The static action power of actuating device can change by change its current's intensity of flowing through.
The present invention also aims to provide a kind of device of online elimination oil whip fault, this device comprises: a detector, near rotor, detect the vibration of rotating machinery, and they are transformed into oscillating signal, and send oscillating signal to controller; One controller links to each other with detector, receives and analyze the oscillating signal that comes out from detector, and the testing signal by the analysis of observation controller is to determine whether to open an electromagnetic actuator device; One electromagnetic actuator device, form by stator, rotor and power supply, on the iron core of stator, be wound with one group of coil, iron core and rotor are stacked or non-laminated formula, and be gapped between rotor and stator, adjustable gaps, after the energising, this electromagnetic actuator device changes axle journal in the relative equilibrium position of bearing, thereby changes the active state of bearing film to axle, online elimination oil whip fault; One installs the fixed plate of electromagnetic actuator device; One electromagnetic bearing, hydraulic support or aiding support.
Advantage of the present invention is: needn't shut down the online elimination that can finish the oil whip fault, can reduce because economic loss and protection equipment that shutdown can cause are not destroyed.For example use electromagnetic actuator, because it is simple in structure, easy to operate, because volume is less, the original-pack unit of change that finds the position to install and need not be bigger easily, there is not other harmful effect, and the effect of eliminating oil whip is remarkable: the vibration situation when Fig. 1 (a) part and Fig. 1 (b) are rotor-bearing system generation oil whip, produce downward static load to the logical quiescent current of electromagnetic actuator this moment, and oil whip is eliminated, system has got back to the periodic motion state of less amplitude again and has seen accompanying drawing 1 (c), the oil whip fault is eliminated, but when turning off electromagnetic actuator, gets back to 3 parts that the oil whip state is seen accompanying drawing 1 (a) sign again.
Description of drawings
Fig. 1 (a) is that axle journal vibrates time dependent schematic representation;
Fig. 1 (b) is axle journal whirling motion track schematic representation when being oil whip;
Fig. 1 (c) adds electromagnetic force rear axle neck whirling motion track schematic representation;
Fig. 2 is the relative equipoise of an axle journal schematic representation;
Fig. 3 is the structural representation of electromagnetic actuator;
Fig. 4 is the controlling party block diagram of the online removing method of oil whip.
Embodiment
Elaborate below in conjunction with accompanying drawing.
Fig. 2 has provided the schematic representation of the relative equilibrium position of axle journal, and wherein w is a static load, and Fe is the tangential force of oil-film force, F
Normal force for oil-film force, what the o point was represented is the central position of bearing shell, o ' expression be the position of journal centre with respect to bearing shell, for a definite bearing arrangement, when lubricating oil viscosity and input pressure have been given regularly, when rotating speed and static load were constant, o ' some position with respect to bearing shell was constant, therefore claimed o ' relative equilibrium position for axle journal.When the size of static load changed, the position of o ' also changed, and along with the increase of w, o ' descends gradually, and stability is good more.When rotating shaft is subjected to certain and disturbs (as the unbalanced force of rotating shaft, bearing working changed condition etc.) the relative equilibrium position of axle journal will change, when rise on the relative equilibrium position to a certain degree the time, just may cause the unstability of system, for example oil whip of said generation.The mode that the oil whip reprocessing takes place often is to shut down reprocessing, causes bigger economic loss owing to shutting down.If at the state of rotor running, online increase static load or the relative equilibrium position of change axle journal in bearing, the relative equilibrium position that helps to reduce axle journal increases stability.
In order to achieve the above object, the present invention has taked following measures.Under the state of rotor running, find that after testing the moment near rotor generation oil whip changes the relative equilibrium position of axle journal, the principle that the method adopted is to apply a downward static load to system is online, specifically adopts electromagnetic actuator device to apply a downward electromagnetism constant force to system.Accompanying drawing 3 is structural representations of electromagnetic actuator device, is made up of stator (comprising iron core 1 and coil 2), fixed plate 3, rotor 4 and power supply (not showing the place), and fixed plate 3 is to be used for fixing the structure division of stator at rotor-bearing system.Stator is a major component in the electromagnetic actuator device, and iron core 1 and rotor 4 can be made by the magnetic property excellent material, be embedded with one group of coil 2 on iron core, but its principle is similar with electromagnetic bearing.Certain clearance Δ (air gap) is arranged, adjustable gaps between rotor and the stator.Pass to static working current for coil 2, because the effect in magnetic field, will produce the electromagnetic force that rotor is pulled down that size is constant, be directed downwards, for bearing, the relative equilibrium position that just is equivalent to have increased a part of static load or changes bearing.Because it need not feedback control system, can directly change the size of electromagnetic force by the size that changes operating current, therefore have reliable and stable performance, can online elimination oil whip.Electromagnetic actuator is a kind of simple in structure, and volume is little, and the saving energy need not feedback control, stable performance, and contactless with rotor.Because volume is less, the mounting point is easier to find.For guaranteeing that the electric current that is led in the coil reaches job requirement, a potentiometer of polyphone and an ammeter in circuit, with the size of electric current in power supply and the potentiometer regulating winding, just can change the size that acts on electromagnetic force downward on the rotor, just change the size of static load.
Fig. 4 is the controlling party block diagram of the online removing method of oil whip.The online cancellation element of oil whip is made up of detector, controller, electromagnetic actuator device three parts.Detector is used for detecting the vibration and the rotating speed of rotating machinery, gives controller with the oscillating signal that they are transformed into; Determine whether to open the electromagnetic actuator device behind the via controller analytic signal.Detector can be selected velocity transducer and displacement transducer for use in the device.Controller can adopt computer or single-chip microcomputer.
During work, vibration detecting sensor output is delivered in the computer after amplifying sampling with oscillating signal, by observing the electrical signal after the Computer Analysis or passing through spectrum analyzer, see and whether produced oil whip, whether decision connects the power supply of actuating device, just hold device energising, produce electromagnetic force, onlinely eliminated oil whip to electromagnetism.
The foregoing description is for the present invention that explains, rather than limits the invention, and in the scope of spirit of the present invention and the claim of adding, modification or change to the present invention carries out all fall within the scope of protection of the present invention.