company news about Solutions to surface defects and other problems encountered in the drawing and bending of aluminum profiles in the processing of precision hardware parts

Solutions to problems such as surface defects encountered in the drawing and bending of aluminum profiles in the processing of precision hardware parts, including problems such as adjusting the curvature of formed profiles, surface defect treatment, distortion treatment after drawing and bending, verticality exceeding the treatment difference, determination of contour processing length, and safety production.
1、 Adjust the curvature of the formed profile
1. According to the theoretical analysis and calculation of the rebound amount, the approximate correction of the die is obtained through the tensile test, so that the profile after stretching matches with the profile sample or check the tire of the die. Considering the instability of the profile, the later correction can be carried out according to the need, which can be pulled over a bit.
2. The curvature change of the bending radius is too large to cause slight deviation, while the cylinder can increase the direction perpendicular to the mold in front of the mold. The profile to be bent coincides with the mold, and there should be no gap between the drawing and bending mold and the drawing profile. This method can solve the bending problem of the inhomogeneous side of the drawing curvature center.
3. In the design process, the form of sectional area of profile and the thickness of each part shall be considered. For the asymmetry of the cross-section area of the profile, the deviation caused by the stress imbalance on the closed side and the release side of the profile can be appropriately increased in the tensile pretension.
2、 Surface defect treatment
1. If the edge of the profile is not in place, it will cause shrinkage and wrinkling, commonly known as mullet edge. If the tensile force is large after drawing and bending, the edge stress is unbalanced, resulting in cracks on the profile. This can be solved by improving the cross-sectional area of the contour or adjusting the tension.
2. Curved surface depression mainly occurs in the cavity contour. This type of profile needs to be filled with filler to fill the curved part of the cavity before drawing and bending. The open cavity can be filled with spring steel plate or Teflon packing, while the closed cavity is usually filled with sand.
3. According to the part that produces side sagging marks, properly adjust the die gap, and the improvement of die material can effectively prevent the profile from being scratched.
3、 Twist treatment after stretching and bending
1. After drawing and bending, the main reason for distortion is the asymmetry of cross section area and the stress imbalance between the closed and released edges of the profile. In view of this, industrial aluminum profiles can improve this problem by increasing the profile tension, that is, adding a vertical pushing cylinder and bending the die in front of the drawing;
2. At the same time, it is better to maintain the pressure for a period of time after drawing and bending. In addition, the trace deformation caused by the unstable extrusion profile must be completed through post-correction.
4、 Verticality exceeds treatment difference
1. After drawing and bending, the verticality exceeding the difference is also caused by the asymmetry of the cross section area and the uneven street closure and stress release of the profile. This situation can be improved by adjusting the curvature changes of the drawing and bending tools.
2. According to the needs of post-correction, it can be pulled slightly, and the trace deformation caused by the instability of the extruded profile needs to be completed through post-correction.
5、 Determination of contour processing length
The rough length of the stretch bending profile is composed of the part length, the mold curvature extension (the part length, the extension part and the mold end fillet are collectively referred to as the effective length of the mold), the clamping part of the equipment chuck and the rotating clearance of the equipment chuck extension mold. In addition to the length of parts, they are collectively referred to as process length. The length of batch production process directly determines the cost of parts.
Therefore, it is recommended to meet the requirements of people in bending parts forming state as much as possible to reduce the effective length of the mold; If necessary, the notch can be opened at the rear of the end of the mold, so that the work machine chuck can freely enter the rear of the mold, thus reducing the process allowance at both ends of the wool.
6、 Safe production
Safety is the primary concern in the industrial production process. Therefore, in the production process, additional protective devices should be added in front of the profile operating platform, corresponding regulations should be formulated, and comprehensive technical operators should be trained. In addition, it is strictly forbidden for operators to stand at the front of the equipment during contour stretching.
conclusion
In short, when designing the cross-sectional area of the section, the tensile force of each section part shall be calculated for the profile to be drawn and bent. In the design of drawing and bending tooling, the curvature rebound change and pre-deformation of industrial aluminum profile should be considered in the later correction to minimize the workload of the correction process.
Safety production is the primary concern of reducing production costs in batch production to reduce the workload of the calibration process and reduce the process length of wire drawing and bending materials.
When the stretch profile is unstable, there will be a small amount of bending profile corridor deviation; If the twist exceeds the tolerance and the verticality exceeds the tolerance, other defects can be corrected and remedied later.