Thick-walled cylindrical and spherical pressure vessels are often subjected to autofrettage, a process in which the vessel is loaded at the inner wall to cause a partial or complete plastic deformation emanating from the inner wall, followed by unloading. This introduces the beneficial compressive residual stresses in the vicinity of the inner wall. Depending on the type of the loading, there are five different types of autofrettage processes— hydraulic, swage, explosive, thermal and rotational. This article analyzes the rotational autofrettage, in which the cylinder to be autofrettaged is loaded by rotating it about its longitudinal axis. The centrifugal forces cause the required plastic deformation in the cylinder. Hence, when the cylinder is unloaded by bringing it to rest, compressive hoop residual stresses are introduced in the vicinity of its inner wall. When long cylinders are rotated about their axes, the distribution of axial stress changes with length of the cylinder and affects the generation of the residual stresses in the autofrettaged cylinder. This effect is investigated here by a finite element method (FEM) analysis of rotational autofrettage of cylinder made up of A723 gun steel. The FEM analysis using ABAQUS® package reveals the presence of tensile axial residual stresses in the vicinity of the inner wall of the cylinder, which increase with length. The tensile residual stresses can be mitigated by constraining the ends of the cylinder during the rotational autofrettage.

厚壁圆柱形和球形压力容器通常要经受自紧应力，这是一种容器在内壁加载以引起从内壁发出的部分或完全塑性变形，然后卸载的过程。这会在内壁附近引入有益的压缩残余应力。根据加载的类型，有五种不同类型的自增强过程——液压、型锻、爆炸、热和旋转。本文分析了旋转自紧，其中要自紧的圆柱体通过绕其纵轴旋转来加载。离心力导致气缸中所需的塑性变形。因此，当气缸通过使其静止而卸载时，在其内壁附近引入了压缩环向残余应力。当长圆柱绕其轴线旋转时，轴向应力的分布随圆柱长度的变化而变化，并影响自紧圆柱内残余应力的产生。此处通过有限元方法 (FEM) 分析由 A723 炮钢制成的圆柱体的旋转自应力来研究这种影响。使用 ABAQUS® 软件包的 FEM 分析揭示了在圆柱体内壁附近存在拉伸轴向残余应力，该应力随长度增加。拉伸残余应力可以通过在旋转自应力过程中约束圆柱体的端部来减轻。轴向应力分布随圆柱长度的变化而变化，并影响自紧圆柱内残余应力的产生。此处通过有限元方法 (FEM) 分析由 A723 炮钢制成的圆柱体的旋转自应力来研究这种影响。使用 ABAQUS® 软件包的 FEM 分析揭示了在圆柱体内壁附近存在拉伸轴向残余应力，该应力随长度增加。拉伸残余应力可以通过在旋转自应力过程中约束圆柱体的端部来减轻。轴向应力分布随圆柱长度的变化而变化，并影响自紧圆柱内残余应力的产生。此处通过有限元方法 (FEM) 分析由 A723 炮钢制成的圆柱体的旋转自应力来研究这种影响。使用 ABAQUS® 软件包的 FEM 分析揭示了在圆柱体内壁附近存在拉伸轴向残余应力，该应力随长度增加。拉伸残余应力可以通过在旋转自应力过程中约束圆柱体的端部来减轻。使用 ABAQUS® 软件包的 FEM 分析揭示了在圆柱体内壁附近存在拉伸轴向残余应力，该应力随长度增加。拉伸残余应力可以通过在旋转自应力过程中约束圆柱体的端部来减轻。使用 ABAQUS® 软件包的 FEM 分析揭示了在圆柱体内壁附近存在拉伸轴向残余应力，该应力随长度增加。拉伸残余应力可以通过在旋转自应力过程中约束圆柱体的端部来减轻。