Apparatus for heating yarn
 A yarn heating element wherein fixed elongated core having a heater therein serves as a support for a sleeve rotatably mounted to and telescoped over the core. The space between the core and sleeve can be varied along their lengths for controlling heat radiated from the core to the shell to control the temperature profile along the length of the shell. Varying the winding density of the heater can serve the same purpose. 
E. I. Du Pont de Nemours and Company
D D
D02J D02J
inventional inventional
James E.
Duncan