An investigation of carburization resistance performance of ethylene furnace tube alloys
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Academic Journals
Abstract
Description
Carburization tests and analysis were performed on some samples of radiant tube alloys of ethylene
furnaces at three petrochemical plants. These tubes had undergone carburization in service with some
losing their structural integrity. This study evaluates and compares the carburization resistance
performances of some of these tubes in service and identifies the cause of their degradation. The
polished surfaces of the test samples were visually observed. The depth of carburization zones for each
test sample was measured. Scanning electron microscopy and energy dispersive x-ray spectroscopy
were used to examine the carburization zones and the rest part of the specimens and to characterize
the microstructure and elemental composition of the tubes’ material. Optical microscope (Image
analyzer) was used to examine the etched surface of each of the test samples. Microhardness testing
was performed to determine their mechanical strength. Visual inspection revealed the sagging in some
of the tubes. Metallurgical assessment indicated that the selected furnace tubes showed relative greater
depths of carburized zones when compared with other tube materials tested. Microstructure of the
tubes showed coarse Cr-carbide precipitation and continuous carbide networks at austenite grain
boundaries
Keywords
T Technology (General), TJ Mechanical engineering and machinery