PREHEATING COLLECTOR BARS AND CATHODE BLOCKS PRIOR TO RODDING WITH CASTrnIRON BY PASSING AN AC CURRENT THROUGH THE COLLECTOR BARS

摘要

Three basic methods for heating collector bars and cathodernblocks, prior to pouring cast iron, are in use today: gas burnersrndirectly impinging on the collector bars, ovens for heating barsrnand blocks separately, and third, passing an alternating electricalrncurrent through the collector bars to heat bars and blocksrnsimultaneously. This paper examines electrical heating using therncollector bar as the heating element. Passing an alternatingrncurrent through the collector bar produces an easily regulated andrnuniform temperature throughout the bar. Radiant energy from thernbar heats the slot area of the cathode block. Temperature levelsrnare adjusted by time and voltage selection. Electrically heatingrncollector bar/cathode block assemblies uses less than 15% of thernenergy required for propane gas burner heating. The method isrnquiet, requires little or no supervision, has no products ofrncombustion to exhaust, and temperatures are highly repeatable.