Phenomena, Causes and Treatment Methods of Boiler Tube Damage
1. The water level of the boiler drops rapidly, the steam pressure and the feed water pressure decrease, and there is a noticeable noise when the boiler tube bursts.
2. There is a sound of steam ejecting in the combustion chamber and flue.
3. The negative pressure in the combustion chamber changes to a positive pressure, and furnace smoke is sprayed out of the furnace door.
4. The feed water flow rate is abnormally greater than the steam flow rate.
5. The exhaust gas temperature suddenly drops.
6. Unstable combustion of the boiler or cause fire extinguishing.
b) Reasons when the boiler tube is damaged
1. The boiler inlet water is not deaerated, causing serious corrosion in the boiler tube.
2. The circulating water in the boiler tube vaporizes, causing a steam pocket in the tube, causing the tube wall to overheat, causing convex hulls and cracks.
3. The quality of boiler feed water does not meet the standards, and the supervision of feed water and boiler water is not enough, causing thick scale inside the pipe.
4. During maintenance or installation, the inside of the pipe was blocked by foreign objects, resulting in poor water circulation, causing local overheating of the pipe and causing the convex tube to burst.
5. The furnace temperature rises and falls too fast, causing uneven heating of some parts, causing water leakage at the nozzle.
6. It was blown away by steam leaks from adjacent damaged soda pipes.
7. The feed water temperature is too low and it is not fully mixed with the furnace fire before entering the tube. Therefore, the temperature of the tube is unevenly deformed, and additional stress occurs at the furnace nozzle, causing water leakage or annular cracks at the furnace nozzle.
8. Incorrect pressure method causes uneven heating of individual parts, causing harmful stress and causing water leakage at the weld of the furnace nozzle.
9. Periodic sewage discharge is too long or the sewage valve is not closed tightly, resulting in poor water circulation, or improper operation and operation, causing damage to the water circulation.
10. The fly ash wears severely.
c) Treatment when the boiler tube is damaged
1. The boiler tube bursts, immediately stop the operation of the boiler, and stop the boiler according to the fault. But keep the induced draft fan to extract the steam in the furnace.
2. After stopping the boiler, strengthen the boiler water supply. If the water pipe has a large crack, and the water level gauge still cannot see the water level after the water supply is strengthened, the water supply should be stopped.
3. The induced draft fan should be stopped after the steam in the furnace is basically eliminated.
4. If the boiler tube is not damaged and can maintain the normal water level, and will not cause a rapid expansion of the accident, the load should be reduced. At this time, the standby boiler should be put into operation as soon as possible. When it deteriorates, the furnace should be shut down immediately.
Permanent Steel Manufacturing Co.,Ltd specializes in the production and supply of high-quality seamless boiler tubes, including high-pressure boiler tubes, medium and low pressure boiler tubes, and seamless boiler tubes, which are widely used in industrial production, heating, power generation, etc.