Hello,

I am simulating in Ls-Dyna a drum seaming process that consists of closing a drum, ie the lid with the body using two additional tools (figure 1).

The tools are set as rigid shells and the drum cylinder body as well as the lid are flexible 3D elements. The material selected for the lid and drum is * MAT_PIECEWISE_LINEAR_PLASTICITY where the strain strain curve has been added to 100% strain. No element failure criteria has been added.

During the analysis of the results, I observed that the tensions on the outside of the region analyzed should present tensile stress results, however, the result presents compression stress (figure 2). That makes sense? Not for me....

In addition, on the internal face that should be compression, tensile stress is observed (????) Figure 3.

Would anyone have any explanation for this?

ps.: I am sharing others results in the files bellow.

Similar questions and discussions