Estimated reading time: 10 minutes
The CNC press brake uses the equipped tooling (general or special mold) to bend the cold metal sheet into various geometric cross-sectional shapes. It is a sheet forming machine designed for cold-rolled sheet metal processing and is widely used in sheet bending processing in industries. Such as automobiles, aircraft manufacturing, light industry, shipbuilding, containers, elevators, and railway vehicles.
CNC press brake machines are generally divided into torsion bar CNC synchronous bending machine and Electro-hydraulic servo CNC press brake machine.
The difference between the 2 types of CNC press brake
- The structure to ensure the synchronization of the two sides of the bending slider is different
The torsion bar bending machine is synchronized by connecting the rigid shafts of the two cylinders at the same time, and the electro-hydraulic servo bending machine is synchronized by the servo synchronization valves on both sides.
- The accuracy is different
The electro-hydraulic servo bending machine has relatively high synchronization accuracy, real-time error feedback, and strong anti-eccentric load capacity of the bending slider. The torsion bar shaft bending machine has no error feedback, and the anti-eccentric load capacity of the bending slider is low.
- The price is different
The controller system of the torsion bar shaft bending machine is different from the system of the electro-hydraulic servo bending machine, and the price of the system itself is very different. For example, the torsion bar shaft bending machine is usually equipped with DA41S, E21, and so on. The control system of the electro-hydraulic servo bending machine is more complicated than the torsion bar shaft bending machine, at least with DA52S, so the price of the whole machine is higher.
- The number of axis is different
The CNC bending machine with torsion axis synchronization generally has two axes, namely X axis and Y axis, such as DA41S, which has a clear and easy-to-operate interface and has data programming for angle and mold parameter input. For electro-hydraulic servo bending machine, we usually say 3+1 axis, 4+1 axis, 6+1 axis CNC bending machine. Generally speaking, for an electro-hydraulic servo bending machine, what do these 3-axis and 4-axis represent?
X axis: the backgauge front and back
Y axis: the slider up and down
Z axis: control the backgauge left and right
R axis: control the backgauge up and down
Compensation axis: mechanical compensation axis
Features of electro-hydraulic CNC press brake
- Direct angle programming, with angle compensation function.
- The grating ruler real-time detection feedback correction, full closed-loop control, back gauge and slider dead gauge positioning accuracy is ±0.02mm.
- The upper mold adopts the quick clamping device, and the lower mold adopts a wedge deformation compensation mechanism.
- With multi-step programming function, it can realize multiple automatic operation, complete the one-time processing of multi-step parts, and improve production efficiency.
- The imported hydraulic system with stable performance and compact structure can be selected according to user needs, and the back gauge can be driven by ball screw and timing belt.
CNC press brake function
- Graphical user interface
The user interface is the dialogue interface between the CNC bending machine system and the user. The graphical user interface should be suitable for various users, including non-professional users. It can be operated through windows and mailing lists to realize graphical simulation, graphical dynamic tracking, and simulation. And fast programming and other functions.
- Visualization of Scientific Computing
Information exchange is no longer limited to expression in words and language, and visual information such as graphics, images, and animations can be directly used. Visualization technology can be used for DWG/DXF, automatic parameter setting, tool compensation, display and visual simulation of the machining process, etc.
- Interpolation and compensation diversification
Interpolation methods include linear interpolation, circular interpolation, cylindrical interpolation, spatial elliptical surface interpolation, thread interpolation, polar coordinate interpolation, polynomial interpolation, etc. Compensation functions include verticality compensation, gap compensation, quadrant error compensation during arc interpolation, pitch and measurement system error compensation, tool radius compensation, temperature compensation, etc.
- High-performance built-in
The bending machine system is equipped with a high-performance PLC, which can be programmed directly with a ladder diagram or high-level language and can be debugged and edited online to create your own application program.
Programming of CNC press brake machine
- Analysis of processing technology
The programmer must first analyze the processing technology of the material, shape, size, precision, and heat treatment requirements of the part according to the part drawing. Reasonably select the processing plan, determine the processing sequence, processing route, clamping method, tool and cutting parameters, etc.; at the same time, consider the command function of the CNC machine tool used to give full play to the efficiency of the machine; the processing route should be short and the number of tool changes should be less.
- Numerical calculation
Determine the process route and set the coordinate system according to the geometric size of the part drawing, calculate the trajectory of the part rough and finishing motion, and obtain the tool position data. For contour processing of parts with relatively simple shapes (such as parts composed of straight lines and arcs), it is necessary to calculate the start point, endpoint of the geometric element, the center of the arc, the coordinate value of the intersection or tangent point of the two geometric elements, and some To calculate the coordinate value of the motion path of the tool center.
- Write the processing program
After the processing route, process parameters, and tool position data are determined, the programmer can write the processing program section by section according to the function instruction code and the format of the program segment specified by the CNC system. If the programmer and the processing staff are separated, the necessary processing diagrams, tool parameter tables, machine tool adjustment cards, process cards, and related text descriptions should also be attached.
- Preparation of control medium
Record the compiled program on the control medium as the input information of the numerical control device. It is sent to the CNC system by manual or communication transmission.
Precision of CNC press brake machine
The repeatability of the slider of the CNC press brake machine is ±0.0004 inches, and the precise angle of forming must use such precision and a good mold. The repeatability of the slider of the hand-controlled bending machine is ±0.002 inches, and the deviation of ±2~3° is generally generated under the condition of using a suitable mold. In addition, the CNC bending machine is ready for rapid mold assembly. When you need to bend many small batches of parts, this is an indisputable reason for consideration.
Method of operating press brake machine
- Avoid accumulative errors, and measure the unfolded size for each folding process;
- Avoid using the bending machine to lean on the side, and avoid leaning at a large angle;
- Products whose edges have been bent by the bending machine must be positioned, and the previous bending angle should be slightly less than 90 degrees;
- Determine the accuracy of measuring tools before processing;
- Do the first inspection before the formal processing, and do the patrol inspection during the processing;
- The bending machine selects the appropriate machine according to the accuracy requirements of the processed products;
- Avoid choosing different tools, and make sure that the tip of the upper die is on the same straight line before processing;
- Choose a good processing method and a good process layout method to simplify the processing difficulty;
- The position of the bending machine is accurate, and any abnormal position needs to be detected immediately.
Various maintenance methods of CNC bending machine
- Before operation, check whether the leakage maintainer and blade are reliable and the power connection is accurate. The function of the steel bar straightening machine is large, and the adaptability is a prerequisite for us to use it. Whether the insulation of all electrical components is perfect, and the transmission part is Does it have a protective cover, and does the fuselage have reliable zero (grounding) maintenance? It can be used only after admitting that there is no problem.
- Before use, the empty car must be tested and the work must be officially started after it is confirmed that there is no abnormality. The steel bar straightening machine must be used after reasonable application.
- When the steel bar is blocked, the steel bar must be pushed tightly. After the movable blade is returned, the steel bar is sent to the knife edge to block it to prevent the processing of the steel bar that exceeds the standard or is too hard. To block special steel bars such as low alloy steel, use high-hardness blades.
- When blocking the short material, it must be clamped with pliers before feeding to prevent the end swinging and hurting people.
- When blocking long materials, two people should operate, and future generations should follow the instructions of the predecessors, cooperate harmoniously, and should not drag and pull.
- In the process of mechanical work, stop adjusting, repairing and cleaning, and the maintenance work of the steel bar straightening machine must be done well.
- When replacing the blade and repairing, first cut off the power and then replace it. The overall coordination ability of the steel bar straightening machine can increase its overall function. The processed steel bars should be coded and placed neatly, and the broken steel bars must be cleaned up. After the processing is completed, the switch is turned off and the switch box can be detached after the lock box is locked.