Page 242 - Water Standards
P. 242

1) Vertical shaft turbine bearing assembly shall meet the following requirements:
                   —Check the elevation and levelness of the bearing flange. The elevation deviation
                    shall be no larger than 2mm and the horizontal deviation no larger than
                    0   04mm/ m.
                   —Turbine guide bearings and their supports shall be preassembled. The center
                    deviation of bearing supports and the turbine shall be no larger than
                    0   40mm.
                   —After the preassembly positioning, positioning holes shall be drilled and posi⁃
                    tioning pins shall be assembled.
                   —The turbine guide bearing can be installed only when the turbine⁃generator axis
                    has passed inspection. During installation, leakage and pressure tests shall be
                    done according to the requirements of Items 14 and 15 of Article 4   2   2 in this
                    specification, and shall meet the design requirements  
                 2) Horizontal shaft turbine bearing assembly shall meet the requirements of Article
                   4   2   9 in this specification.
               4  Installation of the turbine shaft shall meet the following requirements:
                 1 ) Before the installation of the turbine shaft, the flatness and finish on the
                   composite flangeshall be checked.
                 2) For vertical shaft turbine⁃generators, the turbine shaft  s upper flange surface shall
                   be installed lower than the design elevation by 20-25mm. If the turbine shaft con⁃
                   nects with the generator rotor directly, not only the axiality and parallel of the
                   generator rotor flange and the turbine shaft flange, but also the elevation of the
                   generator rotor flange relative to the nozzle axis shall be aligned.
                 3 ) The main shaft  s horizontal or vertical deviation shall be no larger than
                   0   02mm/ m.
                 4) Before installation of the turbine guide bearing, the generator unit axis shall be
                   checked and meet the design requirements.
               5  Installation of the nozzle and its servomotor shall meet the following requirements:
                 1) For the nozzle and its servomotor, tightness pressure tests shall be done before the
                   installation according to the manufacturer  s requirements.
                 2) After assembly of the nozzle and servomotor, the jet needle and servomotor shall
                   be able to move freely under 16% of rated working pressure. There shall be no
                   gap between the jet needle head and opening in case of pumping oil into the servo⁃
                   motor closing cavity under rated pressure.
                 3) Nozzle installation shall meet the following requirements:
                   —The nozzle center line shall be tangential with the runner pitch circle. The
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