Industrial Challenge: Alignment of Turbo-generator Pedestals of Shahid Salimi Power Plant Steam Unit, Neka, Iran

Shaft alignment is always a common problem in rotating assemblies in various industries, especially in power plant equipment, which can commonly be seen in turbo-generators. The prevalent method of alignment in power plant units is to change the positions of bearings and pedestals of the shafts (subhead) in accordance with the protocols and standards defined by manufacturer company, and common in the power plant industry as well. However, the allowed amount of these changes are limited according to the space available around the shafts, and it is possible that after performing these adjustments for several times during major repairs, the amount of misalignment in the shaft exceeds the limits defined in the standards. In this paper, a case study of the turbo-generator shafts alignment in the steam unit of Shahid Salimi Neka Power Plant, Mazandaran, Iran has been discussed. In the ۲۰۱۰s overhaul, it was observed that the misalignment was much higher than the limits defined in the standards, which made it impossible to implement the standards of the manufacturer and the standards common in the power plant industries. Therefore, an innovative method based on changing the position of the main shaft of the turbo-generator along with changing the position of the pedestals has been used. In this method, instead of using the initial and final bearings as the reference, two middle bearings have been utilized as the references for drawing and applying the main direction and extrapolating the values of the deviations of the bearings outside the two selected bearings. After the investigation, the above innovative method has achieved better results in the shaft alignment than the traditional method.

کلیدواژه ها:

Turbo-generator ، shaft alignment ، bearings ، pedestal arrangement ، turbo-set