Calculation Model of Mechanical and Sealing Properties of NiTi Alloy Corrugated Gaskets under Shape Memory Effect and Hyperelastic Coupling: Two Sealing Properties

Abstract

Bolted flange connections are commonly used in process industries. Their sealing performance is greatly affected by the gasket. In this paper, a NiTi alloy corrugated gasket was simulated to reveal its sealing performance, considering the gasket surface roughness, shape memory effect and superelastic effect. A fluid–structure coupling analysis method that takes the real surface morphology of the gasket contact zone was proposed, and a leakage rate prediction model was established. The results showed that NiTi shape memory effect could enhance the sealing reliability in service and lower the leakage rate. The leakage rate of the NiTi alloy corrugated gasket is positively correlated with the internal pressure of the medium and the roughness of the sealing surface. The prediction model of the NiTi alloy corrugated gasket leakage rate has good reliability with an average error of about 16.81% compared with the simulation.

Achievements and Perspectives on Fe-Based Shape Memory Alloys for Rehabilitation of Reinforced Concrete Bridges: An Overview

“…When SMAs are subjected to external force, a stress-induced martensite transformation occurs, and the macroscopic transformation is the deformation of the alloy. Martensite reverse transformation is activated when the temperature rises to A s , and the alloy can almost completely recover to its original shape when the temperature reaches above A f [15][16][17][18]. The SME is reflected in this process, as shown by the red curve in Figure 1.…”