A jack up rig which is one of offshore mobile drilling units is widely used in shelf offshore drilling exploration and production. The unit consist of a buoyant hull fitted with jack up legs which can be raised up or down into the sea bed.
These videos are very fascinating to see because this is how shipyard launch brand new jack up drilling units into the sea. Some major components of a jack up rig such as hull, jack up legs, accommodation are fabricated when the unit is on land. One major component which is derrick will not be installed until a jack up is into the water.