With our 4 roll machines the bottom roll moves up to pinch the plate edge securely against the top roll while the side roll is raised to form an accurate pre-bend, minimizing the flat zone on the plate edge. Pre-bending on a three roll machine requires that plates be tilted down as they are being fed. In contrast, plates are loaded horizontally at the feed level for pre-bending on our four roll machine, which allows the use of horizontal motorized roller tables to help feed the plate. Plate feeding can take place on either side of our four roll machine. If fed from only one side, they can even be placed up against a wall to save floor space. The side rolls are positioned to the right and left of the bottom roll and are on their own axes. The independent axis of each roll helps make a perfect bend. The “back” side roll (at the far side of the feeding point) also functions as a back gauge to square the plate for proper alignment. This eliminates the need for someone to assist the operator. The plate is kept square without slipping during both pre-bending and rolling because of the constant secure clamping of the top and bottom rolls.

Cone rolling is easier on a four roll machine. The side rolls can be tilted to establish the cone angle and the bottom roll can also be tilted to clamp and drive the plate. Our HR-4 series plate rolls are designed to utilize planetary guides. Our HRR-4 series plate rolls are controlled by rectilinear guides that provide the controlled movement required to create accurate bends and this design increases the longevity of the machines life. This system allows bending of as small as 1.1 times the diameter of the top roll, providing the tightest bend radius in the industry. Through superior construction and design, a massive heavy weight frames and the ability to angle bottom and side rolls our 4 roll plate roller can bend wide angle and small diameter conical parts with ease, with minimal effort from the operator. While most machines on the market can conically bend three times the diameter of the top roll, ours can conically bend 1.5 times the diameter of the top roll and frequently smaller diameters than that. Roll cones like a seasoned plate roll operator.

• The fastest and most accurate bends are made by four roll machines. The plate is held securely in place between the top and bottom rolls while the side rolls move vertically to create the bend.
• The bottom roll moves up to hold the plate edge securely against the top roll while the side roll is raised to form an accurate pre-bend, minimizing the flat zone on the plate edge. Pre-bending on a double pinch three roll machine requires that plates be tilted down as they are being fed. In contrast, plates are loaded horizontally at the feed level for pre-bending on a four roll machine, which allows the use of horizontal motorized roller tables to help feed the plate.
• Plate feeding can take place on either side of a four roll machine. If fed from only one side, they can even be placed up against a wall to save floor space.
• The side rolls are positioned to the right and left of the bottom roll and are on their own axes. The independent axis of each roll helps make a perfect bend. The “back” side roll (at the far side of the feeding point) also functions as a back gauge to square the plate for proper alignment (see figure 1). This eliminates the need for someone to assist the operator.
• The plate is kept square without slipping during both pre-bending and rolling because of the constant secure clamping of the top and bottom rolls.
• Four roll machines do not require the operator to remove, flip, and then try to square the plate a second time after pre-bending, as is the case with three roll initial pinch (IP) machines. Keeping the material in the machine makes four rolls 50% more efficient than three roll IP machines, and allows a cylinder to be rolled to the required diameter immediately following pre-bending.
• Bending the back edge takes place after the cylinder is rolled, for a one direction, single pass operation.
• Cone rolling is easier on a four roll machine. The side rolls can be tilted to establish the cone angle and the bottom roll can also be tilted to clamp and drive the plate.
• Four roll machines are the only type of plate rolls that can effectively make use of NC and CNC controls because of the constant clamping and driving of the material during all steps of rolling. Bending difficult shapes like polycentric or elliptic work pieces can be easily done with CNC four roll machines. .