A Temporary Local Rigid Clamping Structure to Improve Antibuckling Ability of the Thin-Walled Cylinder Under External Pressure

Although the inner container of the cryogenic liquid semitrailer works under inner pressure, it needs to be vacuumed during the helium leak detection. Furthermore, the inner container usually cannot meet the stability requirements during the evacuation, though equipped with stiffening structures such as supporting rings for baffles inside the container. Therefore, a kind of temporary local rigid clamping structure was proposed to improve the antibuckling ability of the inner container during the helium leak detection. “Lulu” can was taken as the thin-walled cylindrical shell specimen under external pressure and was clamped with the temporary local rigid ring on the outside surface. The critical pressures were experimentally and numerically studied for the specimen with local clamping rings of different sizes, in which eigenvalue buckling analysis and nonlinear analysis were employed with the aid of ANSYS. It indicates that the critical pressure of the specimen with the local clamping ring is higher than that without the clamping ring. Finally, the optimal clamping scheme including size and location of clamping rings for the inner container of DC18 type cryogenic liquid semitrailer was studied with the finite element method, which aimed to improve the antibuckling capacity of the inner container during the helium leak detection.