The RailTec Process was developed for the rail industry by FTI as a preventative system to diminish rail breakages, track-related accidents and derailments. The life of a bolt hole is increased significantly by producing a zone of residual compressive stresses around the hole by a mandrel pulled through a split sleeve.
This is a quick and easy explanation of how to remove a garbage disposal especially a stuck one! The one in video has already been unplugged from the power as that step is #1 and plumbing trap/elbow also removed (you will need a catching pan for the stinky water.