What Is Sheet Metal Bending?
Sheet metal bending is the process of turning flat sheet metal into three-dimensional through pressure equipment and special molds. It is called bending.
Due to the different materials, thicknesses, lengths, widths of plates, and other shapes and angles to be formed, there are bending machines of varying tonnage and size pressure equipment, with different heights, conditions, and V sizes of upper and lower die with special molds of their unique bodies.
Common types of sheet metal bending machines
Manual bending machine: This bending machine is relatively simple in structure, laborious through manual operation, and suitable for small-size processing.
CNC bending machine：The essence of the CNC bending machine is a CNC bending machine mold for bending a thin plate, which is composed of a bracket, a worktable, and a clamping plate. Because the electromagnetic clamping method is adopted, the pressure plate can be manufactured according to specific workpiece requirements, is easy to operate, and workpieces with sidewalls can be machined.
Hydraulic bending machine：According to the different synchronization methods, hydraulic bending machines can be divided into torsion shaft synchronization, mechanical, hydraulic synchronization, and electro-hydraulic synchronization. Furthermore, hydraulic bending machines are divided into up-moving and down-moving according to different movement modes.
Servo bending machine:Driven by servo motor, the processing efficiency is higher, and the density is more accurate through the visual intelligent operating system. At the same time, the staffing requirements for operators are significantly reduced, and the safety of operators can also be improved. An innovative engineering management interface makes program programming easier. The bending system is combined with ERP and MAS production management systems to meet the requirements of Industry 4.0.
How to use bending dies
The bending die has several bends such as L type, R type, U type, Z type, etc.
The upper die mainly has different angles such as 90°, 88°, 45°, 30°, 20°, 15°, etc.
The lower die has double slots, single slots with different slot widths of 4~18V, R lower die, acute angle lower die, flattening die, etc.
The upper and lower modules are divided into segments and whole:
The upper die segments are generally divided into 300mm, 200mm, 100mm, 100mm, 50mm, 40mm, 20mm, 15mm, 10mm, and the hole is 835mm.
The lower die segments are generally divided into 400mm, 200mm, 100mm, 50mm, 40mm, 20mm, 15mm, 10mm, and the hole is 835mm.
The mold has the ultimate pressure: tons/meter, so when using the mold, the length of the mold should be selected correctly, that is, how much pressure should be added per meter, and must not exceed the pressure marked on the mold.
In order not to damage the mold, we stipulate that when altering the origin, we must use the upper and lower dies with a length of 300mm or more to the source. The upper and lower molds of the same height can only be used after the head is aligned.
When using molds, due to the varying height of various molds, only molds of the same size can be used when selecting molds on one machine, and molds of different heights cannot be used.
When using the mold, the appropriate upper and lower molds should be selected according to the material hardness, thickness, and length of the metal sheet. Generally, the lower mold is used according to the standard of 5~6T, and the size is longer than the sheet material.
When bending an acute angle or pressing a dead tip, you should choose 30 degrees, fold the acute angle first, and then press the finished edge. When bending the R angle, the R upper die and the R lower die should be selected.
When bending long workpieces, it is better not to use segmented molds to reduce tool creasing. Instead, it is better to use single-slot ones because the V-groove outer angle of the lower die of the single groove is significant, and bending creasing is not easy to produce.
When choosing the upper mold, which type of mold to use, we should understand the parameters of all the molds and then decide which mold to operate according to the shape of the product that needs to be formed.
When bending products with tough hardness or too thick plates, it is not allowed to use molds to turn steel bars or other cylindrical products.