The upper roll of the 4-roll plate bending machine is the active roll, and the lower and side rolls are passive rolls. The upper roll is fixed in place, while the lower and side rolls can move up and down. The upper roll is driven by a hydraulic motor, while the rotation of the lower and side rolls is driven by frictional force between the steel plate and each roll. The lower and side rolls are moved up by oil cylinders.
The rotation and reset of the front bearing housing of the upper roll of the 4-roll plate bending machine is achieved by flipping the oil cylinder. Each roll bearing housing and oil cylinder are installed at the left and right ends of the frame. The left and right frames are the main body of the 4-roll bending machine, welded and installed on the overall base. All the operations of the machine are carried out on the control panel.
Operate the lower roll of the 4-roll plate bending machine to rise, making the mother line slightly larger than the working thickness below the upper roll. Then operate the feeding side roller to make the upper mother line on the same level, and then operate the other side to rise between the upper and lower rollers.
Feeding of the 4-roll plate bending machine: horizontally feed the steel plate in, so that the end of the steel plate contacts the entire front roll, and then lower the front roll to its original position.
Tighten the steel plate and pre-bend the end: according to the thickness and material of the steel plate, adjust the pressure of the lower roll circuit within a specific range, operate the lower roll to lift and clamp the steel plate, and start the upper roll rotation. When the steel plate follows to the bending position, stop the rotation of the upper roll. At this time, the necessary clamping length on the left end of the centerline of the upper and lower rolls is equivalent to 1.5 times the plate thickness. Then, lift the rear roll to pre-bend the end of the steel plate.
The 4-roll plate bending machine uses the front roll to pre-bend the other end of the steel plate. After the left end is pre-bent, lower the rear roll to its original position and start the upper roll. When the steel plate follows the above-mentioned bending position, stop the rotation of the upper roll. Before operation, the roller lifts the other end of the pre-bent steel plate, and then adjusts the pressure of the two roller circuits on the left and right.
Pre-bend of the 4-roll plate bending machine with numerical control: adjust the front and rear rolls to the corresponding position required for work, and start the upper roll for forming and bending.
Forming and Bending of the 4-Roll Plate Bending Machine: After bending is completed, lower the lower roll to a lower position, and then lower the workpiece along with the rolls on both sides to a certain position, flip it over, lift the workpiece parallel to the upper roll, take out the workpiece, and complete one work cycle.