Wrinkles, Creases, Web Breaks . . .
A New Solution

By the time you see wrinkles or baggy edges there is a big problem to solve. And the first stop is realizing that what you are looking at are only symptoms . . . not the problem itself. Imperfect webs running on imperfect machines create the shear stress in tho web that results in wrinkles. Controlling the tension profile across the full web width can prevent these problems before they start . . . and at the same time allow you to reduce overall web tension. With Yorkshires new TPC System the tension profile may now be controlled automatically anywhere on the line.

Yorkshire's first solution to web tension profile problems began five years ago with BERS--a manually operated Baggy Edge Removal System that used the unique SLIMB Bearing. With two SLIMB bearings directing a simple straight smooth idler roll Yorkshire developed a simple procedure for removing shear stress to produce a smooth even web. Proven effective over a broad range of applications the Yorkshire BERS gained wide trade acceptance as the only way to prevent web tension problems before they happen.

It was only natural that Yorkshire developed the BERS into a fully automatic system . . . ultimately naming it TPC for tension profile control. Using a set of force transducers, a hydraulic servo circuit, and a sophisticated electronic control unit the TPC System continually monitors the web tension profile detecting the early symptoms of shear stress and correcting them before the trouble starts. Uniform tension across the entire web width is constantly maintained to within 2% of the total tension assuring web flatness at all times. The system's response rate is proportional to the rate of change across the web from a gradual response to a normal shift in the baggy edge position to rapid adjustments for splices and other quick peaks; . . . thus preventing web breaks as splices pass through the system.

In addition to automatically regulating the tension profile the TPC controller offers an operator several options. The digital readout displays either total web tension or differential tension. An override offers the ability to manually position the roll for test purposes and the TPC can also be used to control machine direction tension as well.

Wide Range of Applications

Yorkshire's full automatic TPC Systems have proved successful in a wide ranch of applications from specialty papers such as sandpaper and filter papers to films of all thicknesses and paper of all weights . . . from onionskin to boardstock. The TPC is normally located immediately before primary converter functions such as coating, slitting, laminating, printing, winding, and decurling, etc. Available in widths to 120 in., the TPC runs at speeds to 2000 fpm and tensions from .20 to 10 pli. The systems arc supplied either as free standing assemblies or mounted directly within the primary machine frame. Either way the TPC System from Yorkshire Industries means a perfectly flat web all of the time at minimum gross tensions. TPC doesn't remove wrinkles . . . it prevents them from ever forming.

Reprinted from Paper, Film & Foil Convertor, May 1980.