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During the operation of power station boilers, leakage and explosion of the four tubes of the boiler (economizer, water wall, superheater, reheater) account for about 30% of the total number of accidents, and some units even account for 50%-70% of the total. It can be seen that careful work to prevent leakage and explosion of the boiler heating surface will be very critical to reduce the number of unplanned outages of the unit and improve the health level of the equipment. The following is a brief analysis of the causes of leakage and explosion of the boiler heating surface and the preventive measures that should be taken. There are various reasons for the leakage or bursting of the four tubes of the boiler. The more common reasons include: defects in the pipe itself or aging of the pipe after long operation, poor welding quality, scaling or blockage in the pipe, pipe wall thinning due to pipe wall corrosion or high temperature flue gas erosion, fly ash wear and other reasons, short-term substantial overheating or long-term overheating due to deterioration of cooling conditions, unreasonable heating surface design or installation, improper operation, etc. In order to prevent the frequent occurrence of boiler heating surface leakage and blasting accidents, the following preventive measures should be taken from the perspective of boiler production and operation. 1. Strictly control the boiler parameters and the wall temperature of each heating surface within the allowable range to prevent over-temperature, over-pressure, full water, water shortage and other accidents. The parameters of the boiler start-up and stop phases should be controlled strictly in accordance with the start-stop curve. Monitoring and adjustment should be strengthened when the boiler changes operating conditions to prevent large changes in parameters and over-temperature phenomena on the pipe wall. 2. After the boiler is started and shut down for cooling, the instructions of each header and expansion indicator should be checked and recorded in accordance with the regulations, and the expansion and contraction of each part should be monitored to see if the expansion and contraction of each part are normal. 3. Strengthen the supervision of boiler water and steam to ensure that the quality of steam and water is qualified. When the quality of steam and water is found to be poor, the operating personnel should be notified in time and reported step by step. At the same time, the cause should be quickly identified and dealt with. When the quality of steam and water seriously deteriorates and endangers the operation of the equipment, emergency measures should be taken until the boiler is shut down. 4. Strengthen combustion adjustment to prevent flame deflection. Adhering to the wall, washing the heating surface and other undesirable situations. Reasonably control the air volume and distribution of air volume to avoid excessive air volume or oxygen-deficient combustion. When switching on and off the burner, attention should be paid to a symmetrical and even distribution to minimize thermal deviation and prevent the heating surface from overheating. 5. Soot blowing and removal of slagging in the boiler should be carried out in a timely manner to prevent large slag blocks from falling and damaging the water-cooled wall tubes of the cold ash hopper. 6. Strengthen soot blowing management. Formulate reasonable sootblowing procedures, parameters and sootblowing cycles to avoid blowing damage to the heating surface caused by improper operation or defects in the sootblowing equipment. 7. Strengthen the monitoring of the wall temperature of the heating surface and the temperature of the working fluid such as the water wall, superheater, reheater, etc. If over-temperature is found, the cause should be analyzed in a timely manner, and the operation should be adjusted to restore it to normal as soon as possible and records should be carefully kept. 8. Earnestly implement the equipment patrol inspection system, and if any leakage of the heating surface is found, Notify maintenance and related personnel in a timely manner and deal with it in accordance with relevant regulations on accident handling. 9. Heating surface leakage accidents caused by personnel negligence should be carefully analyzed, the causes identified, and lessons learned, so that corresponding countermeasures can be taken to prevent them. The above is a personal brief analysis of the causes and preventive measures of the damage to the four tubes on the boiler heating surface. I hope everyone will correct the shortcomings. This post was last edited by brainandrain on 2009-2-20 12:58 ]