Hydrodynamics of passive protection from lubricant decomposition products in muffle sintering ovens

Abstract

A passive method is described for protecting the walls of a muffle furnace from lubricant decomposition products. This involves organizing the flow of the decomposition products in the free-convection boundary layer. The mechanism is considered for localizing the lubricant decomposition products around the bottom support and the conditions for doing this. Characteristic values are derived for the thickness and horizontal velocity of the gas mixture in the boundary layer as affected by the ejecting capacity of the layer. Nitrogen is the most economical working atmosphere for removing lubricants from powder components.