Abstract: The measured value of the clearance of generator sealing bush will change due to the variation of the environment temperature. Based on theoretical analysis, a calculating method for correcting the radial clearance value was put forward. By using this method, the error existed in measurement process can be decreased further. This method is active function for increase the measurement accuracy and ensuring safe and economical operation of the equipment.

Key words: clearance of generator sealing bush, measurement accuracy, environment temperature, coefficient of linear expansion, correcting method