Thin-walled shell structures such as those used for space launch vehicles are highly sensitive to various kinds of imperfections. This imperfection sensitivity makes it challenging to predict the load carrying capacity of these structures. A correlation between the manufacturing process and the load carrying capacity, called manufacturing signature, would facilitate the design of these structures. Therefore, in this paper, a step towards a manufacturing signature of flow formed unstiffened isotropic shell structures is made. For this purpose, the investigated shell structures and their manufacturing process are introduced in detail in this work. Afterwards, the geometric and thickness imperfections of these shell structures are measured using an in-house developed measurement system. The measurement results are evaluated in detail and the buckling loads of the measured shell structures are calculated numerically. The results show that all six shell structures have similar knock down factors $\left({\rho }_{\text{i}}\approx 0.74\right)$, which indicates a correlation between the manufacturing process and the load carrying capacity. Subsequently, experimental buckling tests are carried out for three shell structures. The discrepancies between the numerically calculated and the experimentally measured buckling loads are tracked back to load imperfections. Finally, the impact of load imperfections is studied briefly.

诸如用于太空运载工具的薄壁壳体结构对各种缺陷高度敏感。这种不完善的灵敏度使得预测这些结构的承载能力具有挑战性。制造过程与承载能力之间的相关性（称为制造特征）将有助于这些结构的设计。因此，在本文中，朝着流动成型的未加筋的各向同性壳体结构的制造方向迈出了一步。为此，在这项工作中详细介绍了所研究的壳体结构及其制造工艺。然后，使用内部开发的测量系统测量这些壳结构的几何和厚度缺陷。对测量结果进行详细评估，并通过数值计算所测壳结构的屈曲载荷。结果表明，所有六个壳结构具有相似的击倒因子$（{\rho }_{\text{一世}}\approx 0.74）$，它表示制造过程和承载能力之间的相关性。随后，对三个壳结构进行了实验屈曲测试。数值计算和实验测量的屈曲载荷之间的差异可追溯到载荷缺陷。最后，简要研究了负载缺陷的影响。