The remedial measures to eliminate differential expansion increment of highpressure cylinder for a 200 MW steam turbine unit in operation at one power plant have been presented. Through each item of inspection and test

it was found that the cause leading to differential expansion increment of the highpressure cylinder to be steam leakage of the admiting pipe for the highpressure cylinder's sandwich and of the leadingin flange for temperaturemeasuring point of the highpressure cylinder

and defects eliminating treatment has been carried out on the said basis.