Disclosed herein is a vertical drop furnace for melting aluminum and aluminum alloys and a method for melting aluminum and aluminum alloys substantially entirely by convection. Vertical drop furnaces have a refractory brick lining which is usually formed by Cylindrical cross-section and a concave, usually conical, moulded fire hearth. A number of downwardly inclined burners are arranged on the furnace wall in a manner that enables high rate burners to be avoided The flame will blow molten aluminum metal through the furnace and into other burners opposite the furnace wall.
An internally heated curling brush includes a handle, a cylindrical member extending from the handle, the cylindrical member having a longitudinal axis and an outer cylindrical surface radially spaced from the longitudinal axis. The modifications include the above The cylindrical member provides a plurality of thermally conductive hard ridges that are spaced around the circumference of the cylindrical member. The height of the hard ridges is at least half the diameter of the cylindrical member, at least 0.375 inches, and each The base of the hard crucible occupies an arc length of about 20° to 110° on the cylindrical member.
An internally heated curling brush includes a handle, a cylindrical member extending from the handle, the cylindrical member having a longitudinal axis and an outer cylindrical surface radially spaced from the longitudinal axis. The modifications include the above The cylindrical member provides a plurality of thermally conductive hard ridges that are spaced around the circumference of the cylindrical member. The height of the hard ridges is at least half the diameter of the cylindrical member, at least 0.375 inches, and each The base of the hard crucible occupies an arc length of about 20° to 110° on the cylindrical member.