Field Installation of Vanstone Flanges

Spiral Manufacturing’s professionally mounted Vanstone flanges are the easiest and most secure option for most installations. However, there may be times when Vanstone flanges must be fabricated at the installation site. These instructions should be helpful. In addition, you can view a video of how to create a Vanstone flange in the field by clicking here.

Step 1
Slip flange over Spiral ductwork allowing duct to extend 1/2″ beyond the face of the flange. Measure to ensure the flange is square to the duct. Secure flange in place with 3 or 4 C-clamps.

Step 2
Peen 4 tabs about 1″ wide and 90° apart, working from the inside of the flange. The edge of the flange acts as a break. Do not cut, slice, or hammer directly on the end of the duct.

Step 3
Rotate duct 45° and peen 4 more tabs about 1″ wide and 90° apart. There should now be a total of 8 tabs bent over.

Step 4
Peen remaining edge of duct over flange. Flange is ready to be bolted.