If a groove weld has no size, what kind of penetration will it have?

In the context of welding, particularly when referring to groove welds, the concept of penetration is crucial as it defines how deeply the weld metal has fused into the base materials. When a groove weld has no specified size, it typically indicates that the design intends for the weld to achieve a complete joint penetration. This means that the weld will extend completely through the joint thickness, providing maximum strength and ensuring that the joined materials are fully fused together without any voids or weak points.

In structural applications, complete joint penetration welds are often preferred, especially in critical components or where strength and integrity are paramount. By achieving complete penetration, the weld is able to distribute stresses more evenly and withstand higher loads and forces, which is essential in structural applications.

Other penetration types, such as partial joint penetration or insufficient penetration, do not achieve this thorough fusion and could result in weaknesses in the joint, leading to potential failures under stress. Therefore, the answer that identifies complete joint penetration aligns perfectly with the context of groove welds that are expected to deliver maximum performance.