Method of preheating the wall of a furnace channel and article for generating circulation of heated air for preheating the wall of a furnace channel

Abstract

A method of preheating the wall of a furnace channel, which channel extends through a wall of the hearth of the furnace at one location therein, through an inductor mounted on the wall of the hearth, and through the wall of the hearth at another location therein and which opens at the opposite ends thereof into the hearth such that a circulatory passage is defined from and to the hearth through the channel, comprising heating the air in the hearth so as to heat the walls thereof, including directing a lowered-temperature flame from a high turn-down burner into the hearth, generating circulation of heated air from the hearth through the channel to heat the wall thereof, and further heating the air in the hearth and channel to further heat the walls thereof, including raising the temperature of the flame from the high turn-down burner and circulating the further heated air through the hearth and channel, so that the temperature of the walls of the furnace and channel is rapidly elevated to furnace and channel operating temperature, and so that substantially all moisture is removed from the wall of the channel prior to introducing molten metal or a metal melting bath into the hearth and channel to prevent spalling or cracking of the channel wall. An article for generating circulation of heated air for preheating the wall of the furnace channel, comprising a tubular element connected at one end to a source of compressed air and including a return at the other end extending in the direction of the one end, which return end is extendable into the furnace and into one end of the channel for directing a stream of compressed air towards such one end of the channel to draw heated air from the hearth through the other end of the channel so as to heat the wall of the channel.

Dependencies are inferred from the claim text.