Barges, flat-topped barges, and pontoons are used to transport and temporarily store large and heavy parts of wind turbines, like blades, piles, and foundations in the offshore industry. Besides regular flat barges, there are special heavy-duty barges with stronger decks for heavy loads. Semi-submersible barges can sink slightly by taking in water to load and unload floating objects. Launch barges are used to tilt steel structures or foundation parts into the water using a similar sinking method.