Practical guides from the EBR HVAC engineering team on how rectangular and round duct is made, joined and finished, and which machines do each step.
Duct Fabrication Guides
- TDF vs TDC Flange: What Is the Difference? How self-flanged duct joints compare with slip-on and angle-iron flanges, and how they are made.
- Pittsburgh Lock Seam Explained (and When to Use It) What the pocket and male edge do, how the seam is closed and sealed, and how it compares with a snap lock.
- Seam Closers: Pittsburgh Seam Closer vs Duct Seam Closer How a seam closer folds the Pittsburgh lock shut, hand vs machine closing, elbows, sealing and common defects.
- Types of Duct Making Machines: A Buyer’s Overview The main machine families in a duct shop, what each one does and how to choose the ones you need.
- Auto Duct Line or Individual Machines? How to Choose When an automatic duct line pays off, when separate machines fit better, and the shop data to collect before you decide.
- How Spiral Duct Is Made How strip from a coil becomes spiral round duct, what the spiral lock seam is and how sections are joined.
- How Round Duct Elbows Are Made (Gore Elbows) How gore elbows are cut and locked, how many gores a 90 or 45 degree elbow needs, and how to seal them.
- Duct Beading: Why Rectangular Ducts Are Beaded Why rectangular duct panels are beaded or cross-broken, when SMACNA calls for it, and why beads do not replace reinforcement.