The pit furnace is a highly efficient and cost-effective solution for heat treating and stress relieving large fabrications. This type of furnace uses steam as a heating medium, which allows for uniform heating and precise temperature control. The steam atmosphere also helps to prevent oxidation and scale formation on the materials being treated.

Pit furnaces are particularly useful for large fabrications, such as pressure vessels, tanks, and pipelines, which can be difficult to heat treat using other methods. The pit or chamber design allows for the materials to be loaded and unloaded easily, and the steam atmosphere ensures consistent heating throughout the entire fabrication.