Preheating Collector Bars and Cathode Blocks Prior to Rodding with Cast Iron by Passing an AC Current Through the Collector Bars

Abstract

Three basic methods for heating collector bars and cathode blocks, prior to pouring cast iron, are in use today: gas burners directly impinging on the collector bars, ovens for heating bars and blocks separately, and third, passing an alternating electrical current through the collector bars to heat bars and blocks simultaneously. This paper examines electrical heating using the collector bar as the heating element. Passing an alternating current through the collector bar produces an easily regulated and uniform temperature throughout the bar. Radiant energy from the bar heats the slot area of the cathode block. Temperature levels are adjusted by time and voltage selection. Electrically heating collector bar/cathode block assemblies uses less than 15% of the energy required for propane gas burner heating. The method is quiet, requires little or no supervision, has no products of combustion to exhaust, and temperatures are highly repeatable.