Abstract: A method is provided for forming a coating layer on a surface, wherein the coating composition includes at least two reactive components. At least one of the components is encapsulated in a plurality of microspheres, which are then mixed with the second component in a single chamber of a container. The mixture is sprayed from the chamber through a single spray nozzle onto the surface. Then, the microspheres degrade to release the first component and allow the first and second components to react with one another, thereby forming the coating layer on the surface.

Abstract: An electric arc furnace comprises a bottom, a roof and a side wall. The side wall is formed from a plurality of bimetal panels each having an inner copper face and an outer steel face. The roof may be formed with similar bi-metal panels. The hollow panels include internal baffles to define channels through which cooling water flows. The copper face is smooth and free of welds so as to maximize thermal heat transfer by the panels. The copper face enhances thermal efficiency and minimizes maintenance requirements of the panels, while the steel face reduces manufacturing costs of the panels.

Abstract: An end cap is provided for adjacent pipes in the cooling coils of an electric air furnace. Each end cap includes parallel opposite side walls and a curved end portion connecting the side walls. The side walls and end portion define a perimeter edge, the outer portion of which is beveled. The end cap includes a pair of tabs extending from each side wall. The tabs partially fill the crevice between adjacent end pipes so as to provide a stronger weld between the end cap and the pipes. Internal turning vanes in the end cap minimize turbulence of the liquid coolant flowing through the pipes. Similar turning vanes can be provided in the 90.degree. elbows of the cooling coils.

Abstract: A roof structure for an electric arc smelting furnace includes a spider frame for supporting a plurality of independent removable coolant coil sections. An inner coil section is generally annular in shape and includes a coolant pipe which spirals completely around a central opening in the roof structure. An intermediate coil section is also generally annular in shape, but includes a coolant pipe which extends around the circumference of the inner section, reverses itself around the circumference of the first pipe of the intermediate section, and then reverses itself once again around the circumference of the second coolant pipe of the intermediate section, to form a generally serpentine pattern. A plurality of semi-annular outer coil sections are supported radially outwardly from the intermediate coil section. Each outer section includes a first pipe located generally centrally within the semi-annular section and extending from end to end.

Abstract: An end cap is provided for adjacent pipes in the cooling coils of an electric air furnace. Each end cap includes parallel opposite side walls and a curved end portion connecting the side walls. The side walls and end portion define a perimeter edge, the outer portion of which is beveled. The end cap includes a pair of tabs extending from each side wall. The tabs partially fill the crevice between adjacent end pipes so as to provide a stronger weld between the end cap and the pipes. The curvature of the end cap minimizes turbulence of the liquid coolant flowing through the pipes.