The Heavy Duty crane is reserved for the major work within the shipyard like moving large bulkheads, hull plates engines or even keeping the entire ship in place.
It is only capable of fore and aft mobility along the mag rails and additionally capable vertical movement movement for lifting.
The clamps have both grip and magnetization functions. On board computers can gauge the cargo weight, material, density, magnetism etc. with scanning. This data is then processed in correspondence with the magnetized rails to provide optimum momentum depending on the distance. This eliminates any kind of sway between the cockpit clamp section and the mag-rails while traversing with heavy cargo.