Process:

Horizontal flat nibbles are used for round pipe seams, double folded corner nibbles, this type of nibble is used for nibbles on straight pipes. Composite corner bite seam, used for rectangular section of the elbow or straight pipe bite seam.

Limited to the length of the material specifications and ease of installation, the duct should be manufactured in sections, each section of the duct should not be more than 2 m. Each section of the duct is generally connected with angle steel or flat steel flange. If there is no special watertightness requirements for the duct system, the flange and the duct do not need to be welded or riveted, only the duct out of the flange plane plate edge 90 ° can be. The connection of air duct can also be used to insert the piece type or standing bite seam connection method.

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