Structural Design and Dynamic Sealing Failure Optimization of Metal C-Rings

Xiaojiang Li; Li Li; Jiaoshan Hao; Yan Feng

doi:10.6911/WSRJ.202602_12(2).0008

Authors

Xiaojiang Li
Li Li
Jiaoshan Hao
Yan Feng

DOI:

https://doi.org/10.6911/WSRJ.202602_12(2).0008

Keywords:

Metal C-ring seal, control valve, High temperature and high pressure, Radial dynamic sealing, Friction and wear, Surface roughness optimization

Abstract

Targeting the miniaturized static sealing and control valve radial dynamic sealing conditions, this paper constructs an integrated “Design-Verification-Optimization” research framework for metal C-rings. Based on the Inconel X750/718/Ag multilayer composite structure, high-temperature and high-pressure static sealing tests and reciprocating dynamic sealing wear studies were conducted. The results indicate that the helium leak rate of this C-ring at room temperature reaches 6.6×10^-9 Pa• m³/s, and it passed the verification of 21.5 MPa water pressure and 40 high-temperature cycles. Dynamic sealing failure is dominated by friction and wear; when the sleeve bore roughness is reduced to Ra=0.8 μm, the life is significantly extended to over 15,000 cycles, with limited benefits from further reducing roughness. Considering both cost and performance, it is recommended to set the roughness threshold for both the dynamic sealing mating surface and the static sealing surface at Ra≈0.8 μm.

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