Case of CNC Machining for Black Sheet Metal Equipment Bracket

1. Project Background

2. Machining Difficulties

1. High Dimensional Accuracy Requirements: The position tolerance of the mounting holes of the bracket must be controlled within ±0.1mm, and the flatness error of each plane shall not exceed 0.05mm, so as to ensure accurate assembly with other components of the equipment and guarantee the stability of equipment operation.
2. Complex Structural Design: There are various shapes of hollowed – out heat dissipation holes distributed on the bracket. It is necessary to ensure the shape accuracy and position accuracy of these holes, and also ensure that the overall structural strength of the bracket is not affected after the holes are opened, so as to avoid deformation or fracture during use.
3. Strict Surface Treatment Requirements: The customer requires black spray – painting treatment. It is necessary to ensure that the coating is uniform, the color is consistent, and the coating has good wear resistance, corrosion resistance and adhesion, so as to meet the use requirements of the industrial production environment.

3. Jili Solutions

(1) Process Planning

1. Preliminary Analysis and Programming: After obtaining the customer’s design drawings, our engineer team uses professional CAD/CAM software to perform 3D modeling of the bracket and conducts in – depth analysis of its structure and machining process. According to the characteristics of the bracket, a reasonable tool path and machining sequence are planned. At the same time, the cutting parameters are optimized according to the machining requirements of different parts to ensure machining accuracy and efficiency.
2. Blanking: High – quality cold – rolled steel plate is selected as the raw material. According to the size requirements of the bracket, a high – precision CNC shearing machine is used for blanking to ensure the size accuracy and surface quality of the plate.
3. Bending and Forming: The blanked plate is placed on a CNC bending machine, and the bending operation is carried out according to the pre – designed bending program. During the bending process, by accurately controlling the bending angle and pressure, the size of each bent part of the bracket is accurate, the angle is consistent, and scratches or deformation on the surface of the plate are avoided.
4. Punching Processing: A CNC punch is used to machine the hollowed – out heat dissipation holes on the bracket. By optimizing the selection of punches and the punching sequence, the shape and position of each heat dissipation hole meet the design requirements. At the same time, the stress impact on the plate during the punching process is reduced, and the structural strength of the bracket is ensured.
5. Surface Treatment: First, the machined bracket is subjected to pre – treatment such as grinding and deburring to ensure a smooth and flat surface. Then, the electrostatic spray – painting process is adopted to uniformly spray black plastic powder on the surface of the bracket. After high – temperature curing treatment, the coating is firmly attached to the bracket, achieving good wear resistance, corrosion resistance and aesthetic effect.

(2) Quality Control

1. Monitoring During Machining: During the CNC machining process, an on – line monitoring system is used to monitor parameters such as tool wear, cutting force and cutting temperature in real – time. Once an abnormality is detected, the cutting parameters are adjusted immediately or the tool is replaced to ensure the stability of the machining quality. At the same time, after each key process is completed, a high – precision measuring instrument is used to detect the size of the bracket, and machining errors are found and corrected in a timely manner.
2. Finished Product Inspection: After the bracket is machined, a comprehensive quality inspection is carried out. A coordinate measuring machine is used to accurately measure the key dimensions of the bracket to ensure that all dimensional tolerances meet the design requirements; means such as salt spray test and wear resistance test are used to detect the corrosion resistance and wear resistance of the coating; the strength test is carried out on the bracket to verify its bearing capacity and stability in actual use.

4. Project Achievements