1. In order to ensure that the steam turbine can be started at any time after shutdown, the rotor should rotate continuously or regularly after shutdown to eliminate thermal bending of the rotor. In addition, turning can prevent thermal deformation caused by steam leaking into the turbine due to lax valves.
2. Because the runner drives the rotor to rotate, the steam in the steam chamber is well stirred, and the uniform cooling of all parts is realized.
3. When rotating, the oil pump must be lubricated to cool the bearing and take away the heat in the bearing.
4. When the steam turbine rotates, the inertia of the rotor and the impact of the blades can be reduced.
5. When overhauling, you can turn the car or turn the brush slip ring of the exciter. Simply put, it is to reduce the temperature difference between the upper and lower cylinders and the impact torque.
Operating procedures of turning gear:
The inner surface of the meshing gear is milled with spiral teeth to mesh with the spiral shaft, and the meshing gear can slide left and right along the spiral shaft. When turning gear is needed, first pull out the safety pin, push the handle, and hold the motor coupling until the meshing gear is fully engaged with the turning gear.
When the handle is pushed to the working position, the contact of the travel switch is closed and the rotary power supply is turned on. After the motor is started to full speed, it drives the turbine rotor to turn and turn.
When the rotor speed of the steam turbine is higher than the turning speed, the meshing gear changes from the original driving gear to the driven gear, that is, the turning gear drives the meshing gear to rotate, the axial force of the screw shaft changes direction, the meshing gear rotates relative to the screw shaft, and moves along the screw shaft to exit the meshing position.
Then the handle rotates in the opposite direction to the stop position, the travel switch is turned off, the motor stops running, and basically stops working. Manually stop turning, manually press the turning motor stop button, the motor stops, the meshing gear exits, and turning stops. Million car purchase subsidy