Main Structure and Work Principle :
1. This machine is symmetrical rolling machine.
2. This machine is composed of two parts: working part holistically and moving part. Working part is composed of left and right bearing base, one up roller, two bottom rollers, lifting screw and other accessory parts. Lower rollers drive upper roller to move up and down vertically. Drive part is composed of main motor, main speed reducer and other accessory parts.
3. Bottom rollers are driven by main motor through main speed reducer, output spindle of main speed reducer drives two lower rollers by a  group of gears, and the revolve direction of rollers is adjusted by main motor.
4. Upper roller lifted by accessory motor through vice speed reducer drives worm and worm wheel mechanism of right/left rolls bearing base. That is to make the lifting pole do up and down movement.
5. Unloading device is designed to remove the work piece after drums bended into shape. Before unloading the upper rolls move to up limit position, the balance device on upper rolls ends hit upper rolls to make hydraulic tipping device work, then to remove the work piece. 

Parameters of  Mechanical 3-Roll Symmetrical Plate Bending Machine (W11S Series):