The steel metal rolling process is a continuous roll-forming process that uses forming rollers to roll metal sheets, steel plates, or rolled profiles into cylindrical, conical, or oval shapes. Compared with other metal forming processes, the roll bending process can effectively reduce the set-up time, raw material usage, and processing and equipment costs, and it is one of the most commonly used techniques for manufacturing axisymmetric shape parts.
At present, there are many different types of steel plate rolling machines to meet the production needs of various formed parts. These steel plate rolling machines can be divided into two main categories in the market: 3-roll steel plate rolling machines and 4-roll steel plate rolling machines.
4-Roll Steel Plate Rolling Machine
The 4-roll steel plate rolling machine has more flexible and diverse bending functions due to the configuration of one lower roll, and the plate centering, pre-bending and rolling effects are better. Read More:Bending Machine Wikipedia
In the actual plate rolling process with a four-roll steel plate rolling machine, the experience and ability of the operator are largely relied on. The most common method is to use a sample operation or repeated test papers. The production efficiency is very low and the ability of the steel plate rollers cannot be fully utilized. Therefore, the finite element software is used to numerically simulate the rolling process of the 4-roll steel plate rolling machine, and the sample test is carried out according to the simulation results. It is hoped that through the comparison of the results, a set of coiling processes suitable for the 4-roll steel plate rolling machine can be finally obtained.
Steel Plate Rolling Machine
Expert in Plate Rollers. Chinese leader in steel plate rolling technologies. Our commitment to innovation has positioned us as a driving market force in steel plate rolling machine technology areas. Read More:CNC Steel Plate Bending Machine – Best Buyer’s Guide
6 steps of plate rolling process of 4-roll steel plate rolling machine
Step 1#: Metal sheet centering
The purpose of plate centering is to prevent the plate from slipping and deviation during the rolling process. Firstly, raise the left roller of the 4-roll steel plate rolling machine along the track so that the center line of the roller is within the opening height of the upper roller and the lower roller, then raise the lower roller so that the distance between the generatrix and the generatrix under the upper roller is slightly larger than the working thickness, and then operate the right The side roller makes the upper busbar and the lower roller of 4-roll steel plate rolling machine on the same level, and the upper roller rotates to feed the steel plate so that the end of the steel plate is in full contact with the left roller of 4-roll steel plate rolling machine for alignment.
Step 2#: Pre-bending beginning-sheet
The upper and lower rollers of 4-roll steel plate rolling machine rotate forward to feed the material, and continue rolling until the end of the plate reaches the vertical center line of the upper and lower rollers. At this time, the position of the left roller rises by 10~20 mm to pre-bend the end of the plate.
Compared with the three-roll steel plate rolling machine the four-roll steel plate rolling machine can complete the pre-bending of the front and end of the plate without using other equipment and molds, and has a small remaining straight edge and high rolling efficiency and quality. After the plate alignment is completed, the left roller returns to the initial position, the upper and lower rollers reverse and return to the vicinity of the axis of the upper and lower rollers, the right roller rises to the pre-bending position, and then the upper and lower rollers feed forward for front-end pre-bending.
Step 3#: Partially Rolled
After the pre-bending of the front section is completed, the right roller is lowered to a position 30~50 mm less than the pre-bending distance, and then partial rolling is performed to avoid discontinuity between the pre-bending section and the rolling section.
Step 4#: Continuous rolling
After part of the rolling is completed, the right roller falls so that the height of its upper axis is slightly higher than the upper axis of the lower roller by 20 mm, and the left roller rises to the continuous rolling position (the left roller must overlap with the sheet in the forming arc section), Then the upper and lower rollers are fed forward for continuous rolling.
Step 5#: Pre-bending end-sheet
The upper and lower rollers rotate forward to feed the material, and continue rolling until the end of the plate reaches the vertical center line of the upper and lower rollers. At this time, the position of the left roller rises by 10~20 mm to pre-bend the end of the plate.
Step 6#: Close the circle
The plate moves back to the position where it touches the edge of the right roller, then the right roller rises to the set value, the upper and lower rollers rotate in reverse to feed until the plate reaches the center of the left roller and stops, then the right roller rises to the set distance , back up to the vertical centerline of the right roll. According to the above steps, forward and reverse feeding, and constantly adjust the feed displacement of the left roller and right roller until the plate can be closed.
Structure and working principle of the 4-roll steel plate rolling machine
The upper and lower rolls of the 4-roll steel plate rolling machine are active work rolls, and the side rolls are driven rolls. The position of the upper roll is fixed, and the lower roll and side roll can be moved up and down. The upper and lower rolls are driven by hydraulic motors, and the rotation of the side rolls is controlled by the steel plate. Driven by the friction force between the rollers.
Both the lower roller and the side rollers are driven by oil cylinders at both ends to realize the lifting movement. The overturning and reset of the bearing body on the front side of the upper roller are carried out by the overturning oil cylinder, and the bearing body and oil cylinder of each roller is installed in the frame at the left and right ends. The front and rear frames are the main body of the 4-roll steel plate rolling machine, which adopts a welded structure and is installed on the overall base. The pushing device is responsible for pushing the workpiece out of the steel plate rolling machine after the workpiece is rolled and the overturning oil cylinder is flipped in place; all operations of the steel plate rolling machine are carried out on the console.
Compared with the symmetrical 3-roll steel plate rolling machine, the four-roll steel plate rolling machine can directly pre-roll the end of the plate without the help of other equipment molds, and the remaining straight edge is smaller; compared with the asymmetrical three–roll steel plate rolling machine, it can not need The sheet is turned around and rolled into a workpiece. This not only improves the efficiency and ensures the quality of the workpiece, but also has a simple process, convenient operation, and reduces the labor intensity of workers.