Abstract: A method and apparatus for automatically and continuously producing multiple blanks from a coil of sheet material with a minimum of scrap. The apparatus utilizes pinch rolls to advance and retract the sheet material from a coil, while simultaneously a cutter, such as plasma torch, moves transversely to the moving sheet material. Movement of the cutter and sheet material is controlled and coordinated so as to make the desired cuts in the sheet material and produce the blanks of the desired configuration.

Abstract: A method and apparatus for forming the locking bend on a Pittsburgh type seam used in joining the sections during assembly of box-shaped sheet metal ducts. The apparatus provides a means for securely holding the duct without the use of a mandrel to permit the sheet metal along the seam to be bent over by a forming roller moving along the seam so as to complete the joint and lock the seam.

Abstract: A method and apparatus for forming the locking bend on a Pittsburgh type seam used in joining the sections during assembly of box-shaped sheet metal ducts. The apparatus provides a means for securely holding the duct without the use of a mandrel to permit the sheet metal along the seam to be bent over by a forming roller moving along the seam so as to complete the joint and lock the seam.

Abstract: An improved method and apparatus for forming box-shaped sheet metal ducts with Pittsburgh-type seams. The improved method is a continuous process in which the sheet metal is fed from an uncoiler, and after straightening and notching, the leading edge is fed into a single apparatus that performs all of the remaining forming functions. In this single apparatus, the leading edge of the material is formed into the male portion of the Pittsburgh seam, after which the box is formed and then the female portion of the Pittsburgh seam is formed and the material sheared to complete the box section. Using this improved method eliminates the moving of separate parts from one station to another, thereby improving the efficiency of the forming operation and the quality of the resulting box section.

Abstract: A hand-held power tool for installing the corners of transverse duct systems. The tool has powered jaws that, when placed over a standard corner piece and one of the flanges of the duct, will first clamp the corner piece in place on the flange and then crimp the flange over the corner piece to complete the installation. Both operations of clamping and crimping are accomplished with a single stroke of the operating rod of an air cylinder.

Abstract: A system for connectng the ends of sheet metal ducts wherein each duct end is provided with a frame. Corner connectors defining perpendicularly extending arms are associated with each frame, and bolts or other fasteners are utilized for connecting the connectors and frames. The respective frames comprise integral roll-formed sections at the duct ends. The sections include a first portion extending perpendicularly outwardly from the duct wall and a second portion bent rearwardly from the outer end of the first portion. When the frame is formed in this fashion, it is adapted to receive the side edges of respective arms of corner connectors whereby the ducts may be efficiently assembled by locating corner connectors in place and thereafter applying the fasteners used for maintaining the assembly.