Causes of Fractured Y-Type Tee in Adsorption Desulfurization Unit

In view of the fracture of Y-type tee in adsorption desulfurization unit of a petrochemical enterprise, the fracture causes mode the were analyzed by macroscopic observation, chemical composition analysis, scanning electron microscope analysis, hardness detection and mechanical properties test, combined with finite element analysis. The results showed that the fracture mode was brittle fracture, and there was obvious stress concentration on the fracture surface, which was the fundamental cause of tee fracture. Meanwhile under the long-term high temperature and hydrogen-containing environment, the tee exhibited obvious material degradation, low hardness and elongation after fracture, and the impact energy at room temperature was only 5.0 J, which had the disadvantages of high notch sensitivity and obvious brittleness.