Freezing Pipe-Type Cable Oil with Liquid Nitrogen

Utilizing a concentric aluminum shell, aluminum foil, an epoxy sealant, and liquid nitrogen, an efficient and simple freeze chamber was designed and fabricated which is capable of effectively freezing pipe-type cable oil in a relatively short time. Designed to contain liquid nitrogen in contact with the pipe surface, the chamber permits heat absorption at a maximum rate. The short freeze times and freeze lengths attained by utilizing the cold temperature characteristic of liquid nitrogen indicate this technique to be a highly satisfactory method of sectionalizing oil in high-voltage pipe-type circuits in minimum time.