Abstract: The present invention provides heating elements and methods for their fabrication and use. The heating elements of this invention include a spirally shaped structure having a plurality of spiral forms, and may contain a thermally conductive, electrically insulated polymeric coating, such as a fluorocarbon resinous coating of about 0.001-0.020 in. in thickness. The preferred spirally shaped heating elements of this invention provide a lower, preferably substantially lower, flux or watt density than that for a Tubular Heating Element of substantially similar Active Element Volume (in3), wherein said spirally shaped heating element has the same or greater overall wattage rating (total watts) than the Tubular Heating Element. The heating elements of this invention preferably have an Effective Relative Heated Surface Area of about 5-60 in2/in3, with a target range of about 20-30 in2/in3, but can generate a heat flux of about 10-50 w/in2.

Abstract: The present invention provides heating elements and methods for their fabrication and use. The heating elements of this invention include a spirally shaped structure having a plurality of spiral forms, and may contain a thermally conductive, electrically insulated polymeric coating, such as a fluorocarbon resinous coating of about 0.001-0.020 in. in thickness. The preferred spirally shaped heating elements of this invention provide a lower, preferably substantially lower, flux or watt density than that for a Tubular Heating Element of substantially similar Active Element Volume (in3), wherein said spirally shaped heating element has the same or greater overall wattage rating (total watts) than the Tubular Heating Element. The heating elements of this invention preferably have an Effective Relative Heated Surface Area of about 5-60 in2/in3, with a target range of about 20-30 in2/in3, but can generate a heat flux of about 10-50 w/in2.