linkedalu 2020-11-12

Nowadays, bending aluminium extrusion, as an important application material in the field of construction and machinery industry, its output and consumption of the whole industry are growing rapidly. After nearly 10 years of rapid growth, bending aluminium profiles industry has entered a new stage of development and shows many new development trends. For example, the continuous expansion of the application field, in addition to the construction field, also gradually into the home field. In addition, bending aluminium extrusion has been widely used in aircraft and automobile bending aluminium profiles production. In the production of aircraft, the edge strips on the frame rib, the front and rear sections of the fuselage, and the long truss of the engine short bin are the key parts of the aircraft framework, which directly affect the aerodynamic shape of the aircraft, and the shape accuracy requirements are very high. In automobile production, bending aluminium profiles is mainly used to process the hollow bending aluminium profiles of body structure and bumper. Under the condition of maintaining the same impact strength as steel products, bending aluminium profiles can reduce the weight of car body and reduce the use cost. Stretch bending process can realize high-precision bending of aluminum profiles. However, there may be some defects in bending aluminium profiles forming, such as wall thickness thinning, cracking, wrinkling and section distortion. These defects are closely related to the material properties, section shape and process parameters of the profiles, which are very complex.

Like roll bending, stretch bending is one of the common cold bending processes for metal profiles, which has the characteristics of wide application range and stable forming. It is one of the means to produce bending aluminium extrusion. It is especially suitable for the bending of single radius of thin-walled, square tube and special-shaped workpieces. Because the stretch bending die of multi arc workpiece is more troublesome. Tension bending generally has the following characteristics:
1. The general stretch bending equipment or process can only bend the workpiece less than or equal to 180, and cannot process 360 degrees or more bending angle at one time like rolling bending. The reason is general, because there is also a rotary bending equipment, but very rare.
2. During stretch bending, the inner surface of the workpiece is a neutral layer, and all other positions are extended. In other words, in theory, all stretch bending parts will be longer than the original ones.
3. In stretch bending process, no matter what type of workpiece is processed, the head must be reserved (because in general, both ends of the material will be damaged due to stretch bending clamping), which is quite different from roll bending or bending.
4. If the forming radius is small, the workpiece will break and other undesirable phenomena.

Based on these characteristics, bending aluminium extrusion production has been simplified. In today's era of material demand diversity, more and more manufacturers began to pursue their own profile. Therefore, materials such as bending aluminium profiles have been applied well.