Optimization of thin-walled sealing structure based on mechanical simulation

Abstract

In the hydraulic and gas pipelines, even thin-walled cylinder device, the built-in elastomeric O-rings are widely used to ensure their sealing. Unfortunately, a case of excessive radial contact pressure will lead to leakage risk. At the same time, the aging of elastomeric O-ring will result in decrease of radial contact pressure, which can also bring about leakage risk. To increase the life of the seal structure, the external shape memory alloy (SMA) sealing ring is subsequently developed for the actual product. However, excessive contact pressure will cause the leakage risk with the lateral deformation at the outside of the sealing interface of the thin-walled cylinder. Based on mechanical simulation, a proposal for the optimization design of seal structure with thin-walled cylinder is given. That is, the radial contact seal on the inner and outer side of the thin-walled cylinder can simultaneously made by SMA. Results gained show that the theoretical value of the resultant force from the SMA at the inside and outside of the sealing interface of the thin-walled cylinder is zero. The bilateral seal structure with SMA ring can avoid the leakage risk caused by the unilateral force and deformation on the thin-walled cylinder, and effectively prolong the service life of the sealing device.