With the development of economy and the improvement of people’s living standards, the goal of people’s sensory pursuit is also rising day by day. In the metal decoration of some high-end places, the more complex the bending shape of metal sheet jewelry is, the more it can reflect the designer’s design level and trendy style, so as to attract the attention of a large number of customers. At the same time, the workpiece should also meet the process requirements of bending edge arc radius as small as possible, no crease on the workpiece surface and no indentation on the decorative surface. The traditional bending machine can not meet this special process requirements. Therefore, the process of grooving and bending on metal plates came into being. >>> Trumpf >>>Bending
Grooving and Bending Characteristics:
1.The arc radius of the edge of the workpiece is small and the workpiece has no crease.
According to the bending process, the size of the edge arc radius of the workpiece after bending is in direct proportion to the thickness of the plate. The thicker the plate is, the larger the arc radius formed by bending is. After the V-shaped slotting of the metal plate, the remaining thickness of the plate becomes half or even smaller, which can greatly reduce the arc radius of the edge after the bending of the workpiece. In addition, due to the thin thickness of the remaining plate at the bend after grooving, the deformation force during bending will be reduced accordingly, which will not diffuse and affect the non bent area. Therefore, there is no crease on the surface of the workpiece after bending, and due to the thin thickness of the plate at the bend, the reduction of the pressure required during bending can well avoid the risk of indentation on the decorative surface. In this way, it can meet the process requirements of small edge arc radius, no crease on the surface and no indentation on the decorative surface in the metal decoration of high-end places such as hotels, banks, business centers and airports.
2.Reduce the equipment tonnage required for plate bending.
In the bending process, the bending force required by the metal plate is directly proportional to its thickness. The greater the thickness of the metal plate, the greater the bending force required, and the corresponding increase in the required equipment tonnage. After V-shaped grooving is carried out at the bending part of the metal plate before bending, the remaining thickness of the plate is greatly reduced, so that the bending force required for plate bending will be reduced accordingly, so that the thick plate can be used in the bending machine with small tonnage_ Bend on the. This not only reduces the investment in equipment, but also saves energy consumption and site.
3.Bending of complex workpiece and control of rebound force.
Complex parts cannot be bent and formed on ordinary bending machines, but they can be bent and formed by manually bending after opening V-shaped groove at the bending position. In addition, the rebound force and rebound angle can be controlled by controlling the residual thickness of the plate. If the remaining plate thickness after grooving is controlled at about 0.3mm, the rebound angle can be very small, and the rebound can be basically ignored.
1)Suspended bending (also called three-point bending)
The punch presses the workpiece into the die without pressing it against the die wall. When the punch core moves down, the edge of the workpiece bends upward and forms an included angle. The deeper the punch presses the workpiece into the die, the smaller the angle. At this time, there is a gap between the punch core and the die. Hanging bending is also called path dependent process. Each angle requires a specific path. The machine tool control system calculates the path and the corresponding impulse pressure at the same time. The path and punching force depend on the mold, material and product characteristics (included angle, length).
2)Bending in die (also called bottom bending)
The punch core completely presses the workpiece into the die, so there is no gap between the die, the workpiece and the punch core. This process is called clamping. The punch core and die must fit each other accurately. Therefore, each included angle and shape requires corresponding die components. Once the workpiece is fully pressed in, the punch core cannot continue to move downward. The machine tool control system continues to raise the impulse pressure until it reaches the specified value. The pressure applied to the workpiece thus rises, showing the contour of the punch and die. The included angle is gradually stabilized under the action of high pressure, and the rebound problem is almost completely eliminated.
The built-in bending swing arm of the machine tool is composed of C-shaped profiles, on which the lower and upper bending dies are installed. During bending, the C-shaped profile moves upward or downward, or performs a small-scale elliptical movement. The semi-automatic operation of the swing arm bending machine is famous for its rapidity and flexibility. Even small batch production is not inferior. In addition, the first mock exam can also achieve the efficient bending of various radius dimensions on the single die by using the same die.
4)Folding and pressing (combined bending)
The edges of the sheet are usually fully bent (e.g. box edges) and then folded parallel to each other. The finished product is therefore more stable as a whole or forms edge protection. Then, other parts usually need to be hung in the hem. Folding and pressing are completed in two steps: first, the operator folds the included angle of 30 ° in advance, and then puts the workpiece back in and presses the included angle.
As the only single forming process in sheet metal processing, bending process is one of the most important processes in sheet metal processing. The quality of bending process will directly affect the forming size and appearance of products. Therefore, how to ensure the forming size and angle of the workpiece in the bending process is a key research content in the bending process.
According to the bending process, the size of the edge arc radius of the workpiece after bending is in direct proportion to the thickness of the plate. The thicker the plate is, the larger the arc radius formed by bending is. After the notching of the metal plate, the remaining thickness of the plate becomes half or even smaller, which can greatly reduce the edge arc radius after the workpiece is bent. In addition, due to the thin thickness of the remaining plate at the bend after notching, the deformation force during bending will be reduced accordingly, which will not diffuse and affect the non-bent area. Therefore, there is no crease on the surface of the workpiece after bending, and due to the thin thickness of the plate at the bend, the reduction of the pressure required during bending can well avoid the risk of indentation on the decorative surface. In this way, it can meet the process requirements of small edge arc radius, no crease on the surface and no indentation on the decorative surface in the metal decoration of high-end places such as hotels, banks, business centers and airports.
1.Generally, the machining of V-shaped groove is carried out when the customer has special requirements for the bending of sheet metal parts, and the normal bending cannot reach the minimum value required. At this time, use grooving and bending.
2.The structural dimensions of sheet metal parts are specially designed. When the normal bending cannot be reached, it is necessary to plane grooves. For example, for U-shaped structural parts, the inner cavity size is only a few millimeters. At this time, double V-grooves are used for forming.
3.Depth, width and angle of V-shaped groove
The depth of V-groove planed by materials with different thickness is different. The specific processing data depends on the customer’s requirements for products.
Precautions: according to experience, the angle of V-groove planed should be 2 degrees larger than the actual forming angle. The material will rebound during bending and forming, and a gap of 2 degrees is reserved for controlling the angle during processing.
4.Aluminum plate notching
For aluminum plates that cannot be bent directly, slotting shall be carried out before bending. However, if the aluminum plate is grooved and then folded, it is bound to cause great damage to the strength and stiffness of the aluminum plate. Therefore, our company believes that the aluminum plate should be grooved only when it is not allowed, and the depth of the grooving should not exceed half of the thickness of the aluminum plate. Of course, after grooving, the bent fillet is small, generally R is about 1.5 ~ 2mm (depending on the depth of the grooving), while for the aluminum plate without grooving, the bent fillet R is generally 4 ~ 4.5mm (the thickness of the workpiece is 3mm). click here to contact us.