The roll forming machine is the instrument needed to convert strip to a finished cross-section. Common to all makes is a fabricated base, roll spindles, spindle support housings and a drive.
Integral Drive Type
The most popular forming machine is the integral drive type, one head of which is illustrated on Figure #4.
Figure 4: Integral Drive Type Roll Forming Stand
Several manufacturers make this style of machine (Yoder, Dahlstrom & Tishken, to name a few) in standard sizes of 1½”, 2”, 2½” and 3” spindles to accommodate mild steel up to about .180” thick in widths to 24”. Each can be made with as many heads as desired, as few as two or three or as many as thirty-six, although generally twelve to fourteen meet most requirements.
As you can see, each pair of spindles is carried in a separate gear-head and as per Figure #5, each has it’s own splash lubricated worm and gear train. Since the upper roll spindle must be adjustable for rolls of different diameters, it is driven through a toggle or link type gear arrangement from the bottom spindle permitting adjustment without sacrificing pitch line mesh of the gears. A micrometer dial on each adjusting screw indicates spindle adjustment and parallel. The outboard housing is removable from the spindle as a complete assembly to permit roll changes.
Figure 5: Integral Drive Type Roll Forming Stand – Solid Model
Figure 6: Operator’s View of Yoder M-Style Forming Machine
Universal Spindle Type
For applications in which the limits of the self-contained gear-head construction have to be exceeded or in which additional versatility is desired, the spindle arrangement shown on Figure #7 is used.
Figure 7: Universal Spindle Type Roll Forming Stand
Figure 8: Gearbox and spindle housings
Here the gearbox is set back from the spindle housings and the spindles are driven through universal couplings. This type machine has been made with spindles up to 15” diameter for heavy structural products and large pipe.