Page 256 - Water Standards
P. 256

Table 4   2   8-6  Allowable absolute throw of the hydraulic
                                 turbine guide bearing
              Shaft rotational speed (r/ min)  n≤250  250<n<600  n≥600
              Allowable absolute throw (mm)  0   35  0   25    0   20


                     Table 4   2   8-7  Allowable insulation resistance of each
                      part of a suspended generator unit  s thrust bearing

                                        Equipment for
                                Insulation  measuring
                   Thrust bearing
             No                 resistance  insulation   Explanation
                    component
                                 (MΩ)    resistance
                                           (V)

                 Thrust bearing seat                Measure after the installation
              1                   5        500
                   and supports                   of the seats and supports


                                                    Measure when the bearing has
                                                  been totally assembled and the
                                                  rotor has been installed
              2    Thrust bearing  1       500
                                                    Measure before the filling of
                                                  lubricant oil and the temperature
                                                  shall be between10℃ and 30℃



                                                    Before filling with lubricant
                    Embedded                      oil, measure the insulation re⁃
              3                   50       250
                    thermometer                   sistance of the thrust pad from
                                                  each thermometer  s core wire



                 4) During installation, the bearing liner gap shall be adjusted according to the main
                   shaft  s center position and direction and size of the barring gear  s throw. The total
                   installation gap shall meet the design requirements.
                 5) The allowable error of the segmented guide bearing liner gap shall be no larger
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