Flotation nozzle for web handling equipment

A nozzle box assembly for use in apparatus for supporting and guiding a horizontally moving web of sheet material comprising:

• an elongated housing including wall means for defining first, second, and third chambers including an elongated, first chamber which extends centrally and axially of second and third chambers which are located on opposite sides of said first chamber and parallel thereto;
• said second and third chambers each including an elongated discharge nozzle slot extending parallel to said first chamber;
• means for supplying pressurized gas to said first chamber;
• a first plurality of flow openings in said housing for conducting gas from said first chamber to said second chamber;
• a second plurality of flow openings in said housing for conducting gas from said first chamber to said third chamber;
• and
• first and second independently operable valve means mounted in said housing for controlling gas flow through said first and said second plurality of flow openings to thereby control flow to said second and third chambers and from said discharge nozzle slots.