许多石油化工厂使用与管道系统相连接的压力容器，例如，图1所示的容器与管道系统。在这样的系统设计中，有两个相关的问题是常见的。一方面，在容器订货时，由于不知道管道系统作用在容器上的机械负荷，工程技术人员要想设计或确定容器的规格，常常估计这个负荷（例如，支承或热力的）。因此，只考虑容器的内压。另一方面，配管工程技术人员确定管道走向，支承布置并且分析管道系统作用在容器上的反作用力时，有一个相反的问题：他们不知道容器上所允许的热负荷。如果这些负荷超载，容器壁和联接管的交点的应力就会过大。 Many petrochemical plants use pressure vessels connected to piping systems, such as the vessel and piping systems shown in Figure 1. In such a system design, two related problems are common. On the one hand, in order to design or determine the specifications of the container, engineers often do not know the mechanical load on the container at the time the container is ordered. This load (eg, supporting or thermal) is often estimated. Therefore, only the internal pressure of the container is taken into account. On the other hand, when piping engineers and technicians determine pipe runs, support arrangements, and analyze the reaction forces acting on the vessel by the piping system, there is an opposite problem: they do not know the allowable heat load on the vessel. If these loads are overloaded, the stress at the intersection of the container wall and the coupling tube will be excessive.