In a pressure vessel, a spherical crown head can be used as an end head or a middle head. Without a common tangent to connect the surfaces of the spherical shell and cylindrical shell, the connection between the spherical crown head and shell produces stresses and deformation at the edge of the connection, so the head and shell in use need to be stiffened and a stiffening section needs to be arranged. With a stiffening section, stainless steel equipment includes more welding beads and looks less aesthetically attractive. If the shell is stiffened as a whole, the thickness of the shell needs to be increased to the thickness of the stiffening section, which is closely related to the radius of curvature R_i of the spherical crown head. Therefore, in design, the optimization of the ratio of the radius of curvature of the head to the internal diameter D_i of the shell must be considered, to obtain the spherical crown head and stiffening section with the minimum thickness. However, in most cases, the thickness obtained may not be the most economical, because the head may be non-standard, and is usually formed by stamping, requiring a costly die. Furthermore, it is permissible for all thicknesses of the shell to be increased to obtain the entire shell instead of a pieced-together shell, and such design can cause too great an allowance of strength, merely increasing the costs of manufacturing. The design of dual-cavity-tank equipment used for irrigation by a company requires the use of a spherical crown head as the middle head. In the design, the challenge confronted by the authors is to ensure an attractive appearance, as well as an economical and reasonable cost. In the design, the internal volume was slightly reduced, the way of connecting the shell and the stiffening section was changed, and the optimal ratio of the radius of curvature of the head to the internal diameter of the shell was selected, to obtain the most reasonable thicknesses of spherical crown head and stiffening section. Thus, the actual difficulties encountered have been resolved.

中文翻译：

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球冠中头连接结构的改进

在压力容器中，球冠封头可用作端封头或中间封头。球壳和圆柱壳的表面没有公切线连接，球冠头和壳的连接在连接边产生应力和变形，因此在使用中需要对头壳进行加劲和加劲部分需要安排。带有加强部分的不锈钢设备包含更多的焊珠，并且看起来不那么美观。如果壳体整体加劲，需要将壳体厚度增加到加劲段厚度，这与曲率半径R _{i密切相关}球形冠头。因此，在设计中，优化封头曲率半径与内径Di之_比必须考虑壳的形状，以获得具有最小厚度的球形冠头和加强部分。然而，在大多数情况下，获得的厚度可能不是最经济的，因为头部可能是非标准的，并且通常通过冲压形成，需要昂贵的模具。此外，允许将外壳的所有厚度都增加以获得整个外壳而不是拼接的外壳，这样的设计会导致强度余量过大，只会增加制造成本。某公司用于灌溉的双腔水箱设备的设计要求使用球形冠状头作为中间头。在设计中，作者面临的挑战是如何保证美观的外观，以及经济合理的造价。在设计中，略微减小内部容积，改变壳体与加强段的连接方式，选择头部曲率半径与壳体内径的最佳比值，得到最合理的球面厚度冠头和加强部分。这样，遇到的实际困难就解决了。