With the progress and development of the technology in the automobile industry, the requirements for surface quality requirements are also getting higher and higher, and for the sheet metal parts of the outer door panel of the car, The problem of auto exterior door pull handle deformation is the key problem of stamping plate parts, in order to solve In order to solve this problem, the following is a brief explanation and combined with the actual successful experience to In order to solve this problem, the following is a brief description, combined with the actual successful experience to explain.

Common Auto Exterior Door Pull Handle Area Shape

Common auto exterior door pull handle area shape settings are divided into 3 cases, A, B, and C. as shown in figure 1.

a. The A auto exterior door pull handle is set on the concave side of the outer panel of the door, the forming is relatively complicated, and the mold is generally a concave reverse forming.

b. The B auto exterior door pull handle is set on the convex surface of the outer panel of the door, which is the most common structure, the technology is relatively mature.

c. The C auto exterior door pull handle is set in the convex waistline and prismatic area of the outer panel of the door, which is the mainstream design shape, relatively simple to form, and the strength and surface quality of the door handle area is better controlled after forming.

The auto exterior door pull handle shape, size and position setting mainly match the whole car, and need to be just right, some platforms developed by the model will also be affected by other parts, so for an auto exterior door pull handle shape, both to match the whole car, but also to meet the needs of the platform models.

Auto Exterior Door Pull Handle Forming Process

The auto exterior door pull handle forming process is basically the same as that of the outer door panel, as shown in Figure 2, divided into 4 processes: OP10 stretching → OP20 trimming + punching → OP30 trimming + side punching + shaping → OP40 flanging + punching + trimming. Forming process first considers the direction of stretching stamping, in the choice of stamping direction generally to determine the final stamping direction of the door handle contour area practice, mainly to meet the maximum conditions of the door handle area forming requirements; door handle deformation is mainly through OP10 stretching formability to control, generally also in OP40 reserved shaping loam in the case of the former forming can not meet, shaping compensation to solve.

Auto Exterior Door Pull Handle Deformation Check

The auto exterior door pull handle deformation check mainly has two kinds: oil stone polishing and applying bright oil light, through visual inspection to confirm the physical deformation state, as shown in Figure 3. Oil stone inspection: no contact parts exist deformation, deformation size can be detected through the gap ruler, general detection of defective position gap less than 0.01mm within the default qualified; light inspection: through parallel light back and forth movement, local light distortion phenomenon, generally combined with data light analysis and physical comparison to determine the amount of deformation, light inspection is also the most convenient and effective inspection method, and the whole car AUDIT The actual car evaluation is basically the same. In the actual process of sub-process inspection deformation using oil stone is mainly convenient and fast, and does not need light conditions; in the inspection of the finished part more use of light to check.

Auto Exterior Door Pull Handle Improvement Program

(1) Analysis Of Surface Product Defects

As shown in Figure 4, the door handle is recessed, and the recessed distance is about 5mm. The recessed shape is a tendency for the board to gather material inward, which is not conducive to the board pulling away from the shape.

The outline of the door handle is not smooth (arrow at A). In the CAE forming process, the contact time of the sheet forming is not uniform, and the contact time at the corner is late leading to uneven stretching of the appearance surface (arrow at B), which affects the appearance quality of the door handle.

As shown in Figure 5, by extending the corresponding position of the part face to face, while tightening the tensile tendons, the CAE calculation of the defect location has significantly improved, and the defect location is dispersion to the outside of the part, a positive phenomenon; in the CAE oil stone analysis to see the data at the same time to pay attention to the regional scope, in the prism or R corner area becomes smaller than the rectification is effective; if in the prism or R corner outside the flat area of the defect to the outside, the physical state is also an improvement.

(2) Modeling Avoidance Success Stories

Case 1, the door handle is on the convex side of the prism, the surrounding is smooth, and there will be no sharp point to let the parts gather in the forming process. The door handle shape is located at the prism, and the stretching process is Early contact, which can fully pull the material apart.

Case 2, the internal shape of the door handle on a flat or convex surface is shallow, producing less deformation to the exterior area and less impact on the appearance of the dent.

As shown in Figure 6, through the above two groups of modeling cases, the analysis results to see are conducive to improving the appearance of the dent problem, for future reference.

(3) Physical Improvement Success Stories

As shown in Fig. 7, the strong pressure deformation counter compensation is the rectification method to be taken when the physical state still does not meet the quality requirements after the process design optimization, and the area is usually reserved in the mold OP30 or OP40 for research and development.

Specific rectification: first of all, the deformation of the deformation area of the part is measured, generally using the grid method of multi-point measurement, and identify the compensation data and excessive range; there are three areas that need to focus on

Specific rectification: first of all, the deformation of the deformation area of the part is measured, generally using the grid method of multi-point measurement, and marking the compensation data and excessive range.

There are 3 areas to focus on control: one is the immobile area; the second is the excessive area is also a strong pressure area; the third is the compensation area. The next is through the measurement of data on the convex die welding research and processing, general compensation amount in 0.1 ~ 0.5mm or so, in the process of welding research and cooperation need to confirm the convex and concave die clearance in advance, the welding process can be used to reduce the research workload of cold sweat or argon arc welding, in the grinding process maintenance to pay attention to the strong pressure area research and cooperation, to visual pressure marks but no hand feeling is appropriate.

Auto Exterior Door Pull Handle Deformation Conclusion

In summary, the four-door outer plate handles deformation improvement from two aspects: ① parts structure and process, through the optimization of the position structure adjustment, in the analysis software simulation analysis, and finally confirm the rectification program; ② through the post-process anti-compensation research and cooperation to achieve quality improvement; for the deformation of the problem of different reasons, but the underlying principle of the problem is basically the same.

This requires a full analysis of the problems of different structures to develop different specific solutions, the collection and summary of historical problems also to provide a guarantee for the development of the later auto exterior door pull handle parts.