1. After the boiler is stopped, if the drum pressure still rises and possibly exceed the working pressure, the air bleeding valve or the related draining valve shall be turned up, but the boiler shall not be cooled rapidly. 

2. After the boiler is shut down, the de-pressurizing speed shall be slow, and the de-pressurizing shall be controlled for about 36 hours and to zero gradually. 

3. When the drum pressure has not reached 0, it is not allowed not to monitor the boiler and auxiliary equipment. When the power of the motor is not off, it is also not allowed not to monitor the boiler and auxiliary equipment. 

4. After the boiler is shut down, according to the declining situation of water level, it is required to continuously feed water to boiler to maintain the steam drum water level slightly higher than the normal water level. When the water supply is stopped,  the recirculation valve of economizer shall be opened.

5. After the boiler is shut down, it is required to turn down the fan cooling-water valve. 6. When the boiler has been shut down for more than 5 days, the bed materials shall be discharged. 

7. When the boiler is maintained, it shall be cooled according to the following provisions: 

(1) Within 10-12 hours after the boiler has been shut down, all the manhole doors and flue doors, the related damper and baffle shall be closed in order to avoid sharp cooling of boiler. 

(2) After the boiler has shut down for 12 hours, the flue baffle can be appropriately opened to ventilate gradually and water shall be changed necessarily. 

(3)After the boiler has shut down for 24 hours, water can be discharged and fed to the boiler once respectively. 

(4) After the boiler steam drum pressure drops to 0.1 to  0.3 Mpa and the boiler water temperature is less than 80 ℃ or the boiler has been shut down for 36 hours, due to the need of maintenance, the boiler water can be drained off. When the steam drum pressure is below 0.2 MPa, the air vent of drum and related header shall be opened, so that the water can be drained smoothly. 

8. If the boiler is required to rapidly cool, the following procedures shall be taken: (1) After the boiler has been shut down, each door of air and flue gas system shall be closed tightly. 

(2) After the boiler has been shut down for 12 hours, the damper of the induced draft fan shall be opened by 10%. 

(3)After the boiler has shut down for 16 hours, the induced draft fan, the primary fan and Roots blower shall be started for cooling. The rate of temperature-reducing shall be controlled to be < 150 ℃ / h. When the bed temperature is below 200 ℃, stop the fan operation and keep the  damper opening of the induced draft fan at around 15%.

(4) After the boiler has been shut down for 24 hours, and the temperature is below 150 ℃, open the manhole door under the hearth to strengthen ventilation. 

(5) According to the cooling rate, the damper can be adjusted and increased appropriately. 

(6) If the boiler is required to rapidly cool, it must be approved by relevant leaders. 

9. After the boiler has been shut down, the main operation and problems during shutdown and cooling of boiler shall be recorded in the record book.