A folding machine is a simple bending machine that can be either manual or motorized, primarily used for edge processing of products. It is important to note that there is a distinction between a folding machine and a bending machine. Generally, a folding machine is used for plastic products, while a bending machine is used for metal products. Folding machines are used for simple bending operations and were previously used for producing stainless steel sheet products with large and simple shapes. However, these products are now mostly produced using cold bending presses.
Hydraulic Folding Machine:
Operating Principle:
The simplest method involves firmly securing the steel plate with a bending radius on the machine's worktable. The protruding portion of the material is placed on another worktable that can rotate around the center of the bending radius. When the movable worktable ascends, it bends the stainless steel to the desired angle. Obviously, during the bending process, the stainless steel slides on the worktable. Therefore, to prevent scratching the stainless steel, the surface of the worktable must be smooth. In actual processing, a plastic film is usually used to protect the surface of the stainless steel. The upper beam is typically made wedge-shaped to create a gap, allowing the use of appropriately shaped blanks to be folded into rectangular boxes or slots.
Application Areas:
The folding machine is mainly used in the following scenarios:
1. Large-sized sheets: Sheets exceeding 2 meters or those difficult to position and ensure accuracy with a single-person bending operation.
2. Heavy-duty sheets: Sheets weighing over 30 kilograms.
3. Surface requirements without damage: Pre-coated sheets, stainless steel, aluminum sheets, etc.
4. High dimensional and angular accuracy requirements: Meeting subsequent welding accuracy requirements.
5. Small batches with multiple varieties using universal tools to complete all processes on one machine.
6. Arc bending, where the drawn shape is the desired result.
7. Need to meet JIT (Just-in-Time) production mode.
8. Product quality: Excellent quality with guaranteed results.
Application Areas:
Operating Specifications:
1. Before operation, wear tight protective clothing with cuffs fastened. The lower hem of the top should not be open, and changing clothes or draping fabric near the running machine is prohibited to prevent machine entanglement. Safety helmets must be worn, and long hair should be tucked inside the hat. Skirts and slippers are not allowed.
2. Folding operators must undergo professional training and have a thorough understanding of the structure, performance, and correct installation of the machine and molds they operate in order to work independently.
3. Before use, apply lubricating oil and run the machine without load for two minutes to check for any issues.
4. Start working only when the operating speed is normal. Observe the movements of people around and take precautions to avoid injuries.
5. The machine must not be used beyond its specified capacity.
6. In the case of multiple operators, one person should be in command. When flipping or moving the workpiece, the operators on both sides should maintain close communication and coordinate their actions.
7. Materials with welding scars and large burrs are not allowed to prevent damage to the molds.
8. After completing the work, cut off the power supply and perform machine maintenance and clean the environment.
Operating Specifications:
Evolution and Development:
From the primitive manual folding machines to the shared plate flange folding machines, and then to the commonly used pneumatic folding machines and more advanced hydraulic folding machines, the development of folding machines has undergone a qualitative leap.
Evolution and Development:
Difference between Folding Units and Bending Machines:
One commonly used CNC intelligent folding machine, known as a folding unit, is not intended to replace bending machines but serves as a good complement to them. It allows for selective bending processing on either the folding unit or the bending machine, depending on the most suitable option. In terms of the targeted material, the folding unit is designed for plastic products, while the bending machine is designed for metal products. Functionally, both the bending machine and the folding unit are machines used for bending processing according to specific requirements. The following sections will provide a detailed explanation of the differences between folding units and bending machines.
Folding Units and Bending Machines:
1. Different operating difficulties due to principles:
The bending machine controls the bending angle by controlling the downward pressure of the upper blade. During bending, the short edge is on the inside, and the operator needs to support the majority of the material on the outside. For bending large workpieces, two or more employees are required to assist.
The working principle of the folding unit is that the sheet is placed flat on the worktable, and the clamping beam presses down to secure the sheet. The folding beam moves up and down to achieve folding. In all folding processes along one edge, there is no need for repeated manual positioning, flipping, and auxiliary work.
2. Different Design Standards for Flat Patterns
Bending machines use flat patterns determined by the K-factor or deductive bending based on empirical values.
Folding units use SchroderUnfold software to automatically generate flat patterns. The bending deduction for each edge is based on material characteristics and sampling. Depending on factors such as bending length, material thickness, bending angle, flange height, bending direction changes, and positioning methods, the Unfold software provides corresponding bending deductions to obtain the most accurate flat patterns.
SchroderUnfold software
3. Different Skill Requirements for Operators
Bending machines require a relatively higher level of skill from the bending operators.
Programming for folding units can be done intuitively by drawing with fingers or by engineers using software for offline programming, which can be imported via USB or network connection. After programming is completed, the operator's main task becomes simple loading and unloading, eliminating the need for highly skilled bending operators.
4. Operating Positions
Bending machines can only be operated from the front.
Currently, folding units have various structures, such as single folding beam structures, C-type mouth folding beam structures, and independent servo-driven double folding beam structures, to meet different application needs. The clamping beam can be in the form of a flip-flop clamping beam with dual blades or a single-blade mouth structure. With the automatic tool changing device, rotary positioning and feeding device, semi-automatic or fully automatic production can be achieved.
5. Different Dimensional Accuracy for Bending
Folding units, depending on the size of the workpiece, can be operated from the front and back simultaneously or separately, making it easier for observation and use.
The dimensional accuracy controlled by folding units is based on the first bend, using the first edge as the positioning reference. The final controlled dimensions precisely match the customer's required inner clearance dimensions. Since the sheet is processed in a flat position, one person can easily complete the dual-directional positioning (side and rear) and bending reversal.
6. Different Angle Accuracy for Bending
The angle accuracy controlled by bending machines is indirectly controlled by controlling the downward pressure of the upper die, which is related to the material thickness. Additionally, hydraulic drive can cause angle variations due to changes in oil temperature.
Folding units are fully electrically driven, and deflection compensation is based on material sampling and mathematical algorithms derived from experience. With different positioning methods, flange heights, bending lengths, and bending positions, the centrally positioned electric deflection compensation system combined with the tilting function of the folding beam and clamping beam achieves stable and precise angle control with intelligent accuracy.
7. Surface Scratches and Damage to Materials
During operation, bending machines generate relative motion between the material and the lower die, which can leave indentation marks if the surface is not protected. When bending large workpieces, multiple flipping and moving operations are required, which can inevitably cause scratches.
Folding units, on the other hand, completely avoid surface damage because there is no relative motion between the clamping beam tooling and the folding beam tooling and the material. When bending large workpieces, the sheet is processed in a flat position and can be fully processed on one side with a single positioning, effectively preventing surface damage.
Avoiding Surface Damage
8. Tool Configuration
Bending machines often require tool changes or transferring to other machines to achieve certain special bending requirements, such as arcs, which adds the complexity of transferring and storing semi-finished products.
Folding units can be equipped with a design that includes a rotating clamping beam and two sets of clamping beam tooling, allowing all bending processes to be completed in a single workstation. For arc bending or other special bending requirements, there is generally no need to change the tooling, only modifications in the program are necessary to achieve the desired results.
Bending Arcs
9. Tool Life
Bending machines experience tool wear due to the relative motion between the workpiece and the die, requiring maintenance or replacement.
Folding units, on the other hand, largely eliminate relative motion between the material and the tooling, resulting in extended tool life.
Tool Life
10. Drive System
Conventional bending machines use hydraulic drive, which requires more maintenance and is susceptible to environmental factors.
Folding units are designed with fully electric drive systems, reducing maintenance workload and being independent of the operating environment. This enables higher bending precision. A good equipment not only relies on the rationality of mechanical structure design but also considers factors such as material, heat treatment, machining, assembly, and combines a stable and reliable control system with relevant software to achieve long-term precision and durability of the equipment.
