Fife Shifta-Roll Positioning Stands

Details

• Standard stroke range from 126 mm (5 inches) to 228 mm (9 inches)
• Reliable, accurate edge alignment for unwind and rewind guiding
• Electromechanical or hydraulic system operation
• Fast, accurate web positioning
• Easily adapts to new or existing machinery
• Durable construction for low maintenance and long-lasting reliability
• Compatible with all standard Fife sensors and web guide controllers
• Optional Servo-Center available to speed setup and threading

Shifta-Roll Positioning Stands provide accurate edge alignment for Unwind and Rewind guiding. Powered by electromechanical actuators or hydraulic cylinders, these stands were developed to accommodate or replace existing roll stands that would not otherwise lend themselves to automatic guiding applications.
Capable of handling loads up to 5,200 lbs (2359 Kg), these durable stands feature two raceway bases, hardened racerod supports, and carrier blocks with ball bushings or Teflon bushings. Available with or without uprights, or as raceway base assemblies, the Shifta-Roll Positioning Stand easily adapts to new or existing machinery.
Fife Shifta-Roll stands consist of two raceway bases which have carrier blocks with ball bushings or Teflon bushings riding on race-rods. The Shifta-Roll stand can be supplied as bases only, bases with a crossmember connecting the carrier blocks, or bases with a crossmember and uprights for mounting the customer roll shaft chucks. A 2-high, light-duty version is available which includes roll shafts and drag brakes. A hydraulic cylinder or electromechanical actuator provides the lateral force for movement.
Shifta-Roll stands are designed such that the mechanical stiffness gives a mechanical natural frequency approximately 2-3 times the natural frequency of the control system. The crossmember, uprights, and actuator mounting are checked for stiffness. If a hydraulic cylinder is used, the hydraulic natural frequency is designed such that it is high enough to avoid interference with the control system natural frequency. If the mechanical or hydraulic natural frequency are not high enough, then a resonance condition may exist that does not allow the control system gain to be high enough to give good performance. All Fife Shifta-Roll stands are designed to avoid this condition.