Apparatuses and methods for processing optical fiber

A method of heating an optical fiber, the method comprising:

• flowing gas from a common gas channel into one or more gas outlets of a burner, the common gas channel encircling an aperture of the burner;
• and
• igniting the gas to form a flame and heating the fiber with the flame as the fiber passes through the aperture,
• the one or more gas outlets opening into the aperture such that each gas outlet has a gas outlet bore terminating at an inward-facing wall of the burner that defines the aperture,
• the aperture having a diameter greater than or equal to 5 mm and less than or equal to 25 mm, and
• the one or more gas outlets each having a diameter between 0.5 mm and 1.5 mm.

A method of heating an optical fiber, the method comprising:

• flowing gas from a common gas channel into one or more gas outlets of a burner, the common gas channel encircling an aperture of the burner;
• and
• igniting the gas to form a flame and heating the fiber with the flame as the fiber passes along a fiber conveyance pathway and through the aperture,
• the one or more gas outlets opening into the aperture such that each gas outlet has a gas outlet bore terminating at an inward-facing wall of the burner that defines the aperture, and
• an insulating member extending along the fiber conveyance pathway and on opposite sides of the burner.