自由浮动密封瓦摩擦振动原因.doc

自由浮动密封瓦摩擦振动原因氢气是一种良好的冷却介质，但有一个很大的缺点就是易燃易爆，故氢冷发电机必须有密封装置，以此阻止氢气外泄和空气漏入。双流环式密封系统其密封环在密封支座的油槽中可自由浮动，为了防止氢气沿转子轴向泄露，密封瓦与转子的间隙一般在200m以下。由于密封瓦存在一定的椭圆度，运行中会因为密封瓦卡涩，空氢侧油压不均衡等因素，使得密封瓦与转子发生碰摩，引起摩擦振动。 Hydrogen is a cooling medium is good, but there is a big drawback is flammable and explosive, so hydrogen cooled generator must have sealing device, in order to prevent the hydrogen leakage and air leakage into the. Double ring type sealing system of the sealing ring can be freely floating in a sealed bearing oil groove, in order to prevent the leakage of hydrogen along the axial direction of the rotor, clearance sealing pads and rotors are generally under 200 M. Because the sealing tile existence certain ellipse, operation because of sealing Waka astringent, hydrogen side oil pressure imbalance and other factors, so that the sealing pad and the rotor rub-impact, causing friction vibration双流环式密封系统是目前较为普遍采用的形式，其结构如图1所式。密封瓦由瓦座、瓦环、进油口、空侧和氢侧的压力油腔组成。Double ring type sealing system is currently more widely used form, its structure as shown in Figure 1 type. Pressure seal oil chamber Wayouwa seat ring, tile, oil inlet, air and hydrogen side.密封环由两块半圆环并成，通过螺栓连成整圆。当油腔中通入压力油时，在密封环与轴颈之间形成油膜，防止氢气外漏，并且避免发生动静摩擦，同时在密封环左右端面与密封瓦座之间，另有少量的油流过，以防止密封瓦卡涩。 The sealing ring and by two and a half circle, through screw bolts into a circle. When the oil chamber into the oil pressure, oil film is formed between the sealing ring and the shaft neck, prevent hydrogen leakage, and avoid the occurrence of dynamic and static friction between the sealing ring, and left and right end face and the sealing bearing seat, and a small amount of oil flow, in order to prevent the sealing Waka acerbity.双流环式密封系统在正常运行中同时通过两股油流，成为既相互关联又各自独立的油循环系统。空侧密封油系统的油取自汽轮机主油箱，进入密封瓦后由瓦的空气侧流出，与发电机的支持轴承回油一同流回主油箱。氢侧密封油由密封瓦的氢气侧流出后，流回氢侧密封油箱。 Double ring type sealing system at the same time by two shares of oil flow in normal operation, become the oil circulation system of interrelated and independent of each other. Air side sealing oil system of steam turbine oil from the main tank, into the sealed tile by tile outflow of air side, and the support bearing return oil to flow back to the main generator tank. The hydrogen side seal oil by hydrogen side sealing pad out, back to the hydrogen side seal oil tank.密封瓦与发电机转子之间的碰摩是一种典型的动静摩擦故障，其影响因素众多，碰摩引发振动的机理下面将从密封瓦的结构和密封油系统及其设备上进行分析。 The sealing between the tile and the generator rotor is a typical static and dynamic friction fault, it has many influence factors, the mechanism of friction induced vibration will analyze the sealing pad structure and seal oil system and its equipment.1 从密封瓦的结构上分析 1 from the sealing pad structure analysis假设密封瓦左右端面的径向压力变化是线性的，则密封瓦的压力分布如图2所示。 The radial pressure change hypothesis sealing watts surface is linear, the bearing pressure distribution as shown in figure 2.在正常情况下，密封瓦左右端面上所受的力应是平衡的，这样其浮动性能是最好的。但往往实际的运行情况与假设的理想状况是大不相同的，密封瓦左右两个端面所受的作用力是不相等的，这就存在酱油轴向力的作用，使得密封瓦的浮动性能变差，密封瓦的某一侧很容易与转子发生径向碰摩。 Under normal circumstances, the sealing watts the end face of the force should be balanced, so that the floating performance is the best. But the ideal and actual operation assumption often is not the same, seal watts force two end by is not equal, the axial force, the sealing pad floating performance variation, one side of a sealing pad is easy with the rotor radial rub.2 密封油系统及其设备对密封瓦动力特性的影响 2 oil system and its equipment sealing of tile dynamic characteristics affect the seal2.1 供油设备的影响 氢侧密封油的油压和油量调节是由平衡阀来完成的，平衡阀的控制信号为两个压力信号，分别取自空、氢侧的密封油压。平衡阀的作用就是使氢侧油压始终跟踪空侧油压，使两者的压力差趋于最小。但实际运行中由于管道布置不同，泰山奇石管道长度不同造成流体阻力不同，压降不等，平衡阀、压差阀质量不好，油质不合格造成平衡阀、压差阀卡涩，密封瓦间隙偏大均会造成平衡阀调节精度下降，影响到密封瓦的平衡。平衡阀调节精度高，氢侧密封油箱自动补排油次数会明显减少，使空、氢侧的窜油量趋于最小，也使密封瓦两个端面的压力差趋于最小。 Oil pressure and Oil hydrogen effect of side 2.1 oil equipment sealing oil amount adjustment is accomplished by balancing valve, balance valve control signal for the two pressure signal, seal oil pressure were taken from the air, hydrogen side. Balance valve is the role of the hydrogen side oil pressure always follow the air side pressure, the pressure difference to minimum. But the actual operation due to piping, pipe length difference caused by different pressure drop of fluid resistance, unequal, balance valve, pressure valve quality is not good, oily unqualified cause balance valve, pressure valve jam, bearing clearance is too large will result in balance valve to adjust the precision drops, affect the sealing watt balance. Balance valve to adjust the precision is high, the hydrogen side seal oil tank automatic fill oil discharge times will be significantly reduced, making the air, hydrogen side oil leakage quantity to be minimal, the sealing pad two end of the pressure difference to minimum.2.2 油质和油压、油温的影响 密封油的油质劣化或者油中含有杂质，导致密封瓦油清洁度不能满足要求将会影响到密封瓦在密封油膜中的浮动特性。另外油温和油压的变化也会对密封瓦的浮动特性造成影响，严重时会造成密封瓦的卡涩失灵。Containing impurities effect of 2.2 oil and oil pressure, oil temperature sealing oil deterioration or oil, resulting in seal tile oil cleanliness can not meet the requirements will affect the characteristics of floating seal tile in oi