Steam Engine Fire Tube Boiler
A fire-tube boiler is a type of boiler invented in 1828 by Marc Seguin,[1] in which hot gases pass from a fire through one or more tubes running through a sealed container of water. The heat of the gases is transferred through the walls of the tubes by thermal conduction, heating the water and ultimately creating steam.
I made this one to go with the steam engine I made, it's not made of Plastic, but metal, due to it requiring fire and in order to prevent leaks.