Chain Failure

Описание: Chain links are one of the important mechanical elements for securing a ship to a mooring or an anchor and in lifting operations. The integrity of a chain link depends not only on the material and manufacturing process but also on the stress state developed in the chain due to the load cycle in service. The stress distribution in a chain link when subject to tension or a combination of tension and bending can be determined using small deformation beam theory or finite element analysis.

The finite element analysis of a round chain link are presented below. The link is subjected to quasi static axial load until failure. As we know, implicit time integration is preferable for quasi static problems. However, once the failure occurs, the problem becomes a dynamic one and explicit time integration is needed. Therefore, an implicit-explicit switch is adopted in this analysis.

We notice in the second video that the internal energy (which reflects the deformation) reaches a maximum of 2000 kJ. However, as we can see from the first video, the kinetic energy exponentially rises beyond 5000 MJ after the chain snaps which makes it a very dangerous phenomenon (check the video here for an actual footage of fatal accident during mooring operation: https://lnkd.in/dqH_FaUc).

The failure analysis of a chain link will be one of the examples covered in the upcoming LS-DYNA workshop. For more information and registration, check this link: https://lnkd.in/dpweUM9K

#mechanical #safety #cablesnap #failure #acident #fatal #mooring #lsdyna