Abstract: The composite seal structure of highpressure heat exchanger is a new sealing technology. It has the features of compact structure, reliable sealing, low input cost, longterm use, convenient maintenance and so on. This structure is composed of Omegashaped seal ring (abbreviated as Ωshaped ring) and Cshaped seal ring (abbreviated as Cshaped ring), providing a dualsealing. This paper introduces the structures and manufacturing methods of Ωshaped ring and Cshaped ring. Combining with the design conditions of the highpressure heat exchanger of a fluidized bed residue unit, it also adopts ANSYS software to analyze and verify the composite seal structure and summarizes the advantages of composite seal structure compared with other seal structures of highpressure heat exchangers. The analysis results demonstrate that the composite seal structure combining Ωshaped ring and Cshaped ring can ensure leakfree and reliable operation of heat exchangers, offering a novel approach to address sealingrelated technical challenges in the manufacturing and application of largediameter highpressure heat exchangers.

Key words: highpressure heat exchanger, composite seal, Ω seal ring, Cshaped ring, finite element analysis