Boiler Water Shortage Accidents and Treatment Measures

Boiler Water Shortage Accidents and Treatment Measures
There are two types of boiler water shortage: slight water shortage and severe water shortage.
Slight water shortage: When the boiler water level drops below the minimum allowable water level or the water level gauge cannot directly see the water level, but the water level can be displayed by calling the water operation.
("Call water" operation: first open the drain valve at the bottom of the water level gauge, then close the steam connecting pipe cock, keep the water connecting pipe cock open, and then slowly close the drain valve to observe whether there is a water level in the water level gauge. After a water level appears, Open the steam connecting pipe cock.)
Serious water shortage: When the boiler water level gauge cannot see the water level, and the water level cannot be called up by the water call method. Indicates that there has been a severe water shortage.
1. Accident phenomenon:
1. The water level in the on-site water level gauge is lower than the minimum safe water level, or the water level is invisible;
2. Although there is a water level in the on-site water level gauge, the water level does not fluctuate, which is actually a false water level;
3. The central control water level is displayed as low water level. The temperature of superheated steam rises significantly;
4. The difference between the steam flow rate and the feed water flow rate increases significantly, but the opposite phenomenon occurs when there is a shortage of water due to pipe bursts.
2. The cause of the accident:
1. The staff are negligent, insufficiently monitor the water level, or fail to identify the false water level, resulting in misjudgment and misoperation;
2. Dirt blockage or rupture of the boiler feedwater pipeline or damage to the valve, resulting in a drop in feedwater flow; a failure of the boiler feedwater pump causes a sudden drop in pressure and a drop in flow;
3. The water level transmitter is distorted in the display of the central control water level due to the mixed vapor bubbles in the pipeline condensate or the blockage of the pipeline impurities;
4. The boiler automatic feed water regulation system fails, and the steam flow or feed water flow display is incorrect or deviation, causing water shortage accidents;
5. The boiler blowdown valve leaks or forgets to close;
6. A pipe burst accident occurred in the boiler pipe;
7. The feed water of the economizer section forms a "steam plug" due to high temperature, which causes the feed water flow to decrease or be interrupted.
3. Accident handling:
1. Inform the on-site inspection personnel to check the water level with the central control. When the water level is not visible, close the steam valve, open the water valve and the sewage valve, and no water flows out, it can be judged as a water shortage accident.
2. Carry out the "calling water" operation. If there is a water level in the water level gauge after the "calling water", it indicates a slight water shortage, and if there is still no water level in the water level gauge, it indicates a serious water shortage.
3. When the boiler is slightly short of water, the bypass baffle should be opened to reduce the amount of air entering the furnace, reduce the boiler evaporation, and reduce the boiler load. The central control manually replenishes water to the steam drum. At the same time, the cause of water shortage must be quickly identified.
(1) If the water level transmitter fails, carry out the corresponding exhaust steam and sewage operation;
(2) If the automatic water supply adjustment fails, deal with it accordingly;
(3) If the water supply pipeline is blocked or the valve is damaged, check the pipeline; if the boiler feedwater pump fails and the water pressure is low, check the water pump, and start the backup pump and put it into operation at the same time.


Post time: Jun-29-2021