A Dragon Forge is a blacksmith's forge designed to be heated with dragon fire. Dragon fire has special properties and imbues magical items when used in enchantments. This is in addition to dragons being able to make fire much hotter and faster than any chemical methods. While dragons have occasionally been enslaved in dragon forges, for the most part (and for best results) they are willing participants.
In The Dragonlands, for example, all of the forges and foundries are heated by dragonfire. Although the dragons rule the region, they consider this to be a simple neccessity, as gathering wood or coal for these purposes would waste valuable resources.
Numerous forges have also employed captured Hellkites; but hellkite fire lacks the magical properties of true dragonfire and is not as effective. It is, however, a potent replacement for chemical fire.