Cause analysis of furnace tube leakage
Thread Content
There is a leakage in the furnace tubes of the heat transfer oil steam generator; it was put into use in June 2020. The issue is not a leakage in the tube sheet, and there are no problems with the water used for the boiler. More than 30 tubes are leaking. The operating temperature of the heat transfer oil is 220°C – heat transfer oil flows inside the tubes while pure water flows between them. What could be the cause of these tube leaks?
Such problems stem from the analysis of harmful elements in the two media, as well as potential corrosion of the tube bundles and impact wear caused by physical impurities. Another factor is the vibrations that occur during use, such as the \"steam hammer\" phenomenon caused by the vaporization and condensation of cooling water, as well as vibrations transmitted through the medium; these can be the main causes of damage. For reference.
Reasons: 1. Poor quality of the tube bundle; 2. Large fluctuations in operation, with the liquid level in the steam generator rising and falling sharply, or even leading to dry burning； 3. The water used for replenishment has poor quality, with a high chloride content that causes corrosion of the tube bundles. 4. Poor manufacturing quality (not constructed in accordance with the construction drawings). 5. Design flaw.
There should be no problem with the heat transfer oil, as there are no leaks in the tubes on the side of the heat transfer oil furnace. Exclude corrosion caused by heat transfer oil
Is the formation of steam hammers related to frequent start-stop of the furnace and changes in load?
Production lines with unstable steam consumption that fluctuates greatly operate in a batch mode
Was the location of the leak examined via endoscopy? ? ?
That’s for sure. Try to avoid this phenomenon by changing the way it’s started, just for reference.
The image isn’t very clear; it seems to be a problem with the welding of the tube sheet and the heat exchange tubes. From the image, it appears that the welding was done manually and of poor quality. The spacing between the tubes also seems a bit too small. It appears that this heat exchanger was manufactured in a small workshop, as the machining marks on the tube sheet surface are excessively obvious. It seems this heat exchanger is no good anymore and needs to be replaced.