What should be done if the barring gear stops operating due to some issue when the cylinder temperature is high?

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In cases where the cylinder temperature is high, if there is a problem with the turning gear, it can be handled according to the following principles: (1) When the turning gear cannot function, manually turn the shaft. Meanwhile, keep the oil system running continuously. During this period, monitoring of the bearing temperature should be strengthened. (2) If the rotor cannot be rotated due to reasons such as collisions between the rotating and stationary components inside the turbine caused by thermal shock and the resulting deformation, a cylinder sealing procedure should be carried out, and an attempt to rotate the rotor can be made again after an interval of 1 hour. Under no circumstances should one attempt to start the machine by feeding steam to the crew or use a crane to force it to rotate. (3) When the barring motor experiences overcurrent, the temperature difference between the upper and lower parts of the cylinder exceeds the specified value, or an obvious sound of metal friction is heard, continuous barring should be stopped and regular barring should be adopted instead. Rotate the shaft 180° regularly as required. Closely monitor the data in the TSI eccentricity table, and carefully record the eccentricity values, as well as the time and number of disk rotations. (4) If two out of the three jacking oil pumps fail, one jacking oil pump should be started. As long as the jacking oil pressure is normal, the turbine can be turned, but the DC lubricating oil pump should be started to increase the amount of lubricating oil. If all three top shaft oil pumps fail to operate, the cylinder should be sealed, and maintenance personnel should be contacted to carry out repairs as soon as possible. After repair, the rotor should be rotated 180° to straighten it before resuming continuous turning. (5) When resuming continuous barring after an interruption, the rotor eccentricity should be monitored, and attention should be paid to any friction sounds from the moving parts of the unit. (6) Casing sealing method: Close all drain valves on the cylinder and steam extraction pipes to isolate all sources of steam entering the turbine and condenser. Once the temperature difference between the upper and lower cylinders is less than 50°C, use the 180° rotation by gravity method to straighten the rotor; once the rotor’s vibration level is within normal limits, resume continuous rotor rotation.