During design selection, it is often encountered that the actual flue gas temperature is slightly higher than the nameplate margin, causing local overheating of the finned tube bundle. In this case, the design temperature and operating margin should be verified to ensure that the base tube material meets the requirements.
The base tube can be made of heat-resistant alloy steel, with a design task temperature of up to 850°C, meeting the hot air circulation requirements of the heater. When checking the nameplate, maintenance personnel are advised to focus on the margin between the design temperature and the actual on-site flue gas temperature, as well as whether the interface flange standard is consistent with the existing pipeline.
For high-temperature dust-laden conditions, the fin spacing can be designed at 8~12mm to reduce ash bridging. Note that the fin side is not suitable for liquid media prone to scaling, otherwise the cleaning frequency will increase significantly.
It is recommended that the interface flange standard be consistent with the existing pipeline for easy installation. Regularly check the ash deposition on the fins and clean as needed.
