Abstract: The shafting vibration of the unit No.1 in Baotou Power Generation Branch of Huadian Inner Mongolia Energy Company Limited was larger. The reason of the larger vibration was analyzed; and it was considered that the main reason of the vibration is mass unbalance of the shafting. In last stage blade in the two ends of the lowpressure II rotor and the coupler between the lowpressure II and the generator rotor, the dynamic balance weight measures were adopted. In stable operation of the system with full load, the shafting vibration is less than 70μm, which achieved the good index specified in relevant national standard.

Key words: shafting vibration, amount of unbalance, sway degree, shafting dynamic balance, balance weight, critical rotating speed