Transfer line exchanger (TLE) is an important equipment for ethylene cracking unit. In actual operation

coke formation occurs on the inner surface of tubes in TLE. In effectively inhibit coking on the inner surface of tubes

inert coating of Cr/W/REO was applied on the surface of the tube metal. With aids of ethylene cracking simulator

metallurgic microscope

electronic scanning microscope (SEM)

and transmission electron microscopy (TEM)

coking inhibition performance of inert coating was studied

including the characteristics of coke surface and coking amounts of specimens. Serious coking occurred on the blank specimen surface with catalytic coke and granular coke

while the coated specimen showed great anti-coking effect without catalytic coke and the coke layer was easy to remove. Coking inhibition rate reached 79.1%.