Precision sheet metal manufacturing technology
Aug 28, 2025
In the field of precision sheet metal manufacturing, precision control directly determines product performance and assembly compatibility, especially in high-end fields such as automotive electronics, medical equipment, aerospace, etc., where the dimensional tolerance requirements for sheet metal parts often reach the level of ± 0.05mm. Among them, CNC bending and stamping forming are two core machining processes, and their precision control needs to cover the entire process of "equipment process material detection", achieving micrometer level precision management through multi-dimensional collaboration.
CNC bending
1. Equipment and molds: the "basic guarantee" for precision control
Bending machine selection and calibration: High precision bending machines are preferred, with a sliding block repeat positioning accuracy of ± 0.01mm
Mold design and maintenance: The gap between the molds should match the thickness of the sheet metal. If the gap is too large, it can cause burrs on the bent edges, while if it is too small, it can scratch the sheet metal.
2. Process parameters:
Bending sequence optimization: Following the principle of "inside first, then outside, small first, then large, special first, then conventional".
Bending speed and pressure regulation: Set differentiated parameters for different materials of sheets, and reduce local stress concentration of the sheets through "segmented compression"
Industry Applications
The precision requirements for precision sheet metal parts vary significantly in different application fields, and appropriate control methods need to be selected based on specific scenarios.
| Application field | Typical products | Precision requirements for CNC bending | Precision requirements for stamping forming |
| Automotive Electronics | Vehicle mounted controller casing | Angle tolerance ± 0.5 °, flatness ≤ 0.1mm | Aperture tolerance H8, positional tolerance ± 0.05mm |
| Medical device | Surgical instrument bracket | Angle tolerance ± 0.3 °, verticality ≤0.05mm |
External tolerance ± 0.03mm, burrs ≤ 0.02mm |
| aerospace | Satellite component sheet metal structure | Angle tolerance ± 0.2 °, half bent Diameter tolerance ± 0.05mm |
Aperture tolerance H7, coaxiality ≤ 0.02mm |
Stamping forming
1. Mold design:
Accurate calculation of mold clearance: Determine a reasonable clearance based on the thickness and material of the sheet.
Optimization of guiding mechanism: adopting a "four guide columns+ball guide sleeve" guiding structure.
2. Equipment and materials:
Pre treatment of sheet metal: Before stamping, the sheet metal is subjected to "leveling and flattening" treatment to ensure that the flatness of the sheet metal is ≤ 0.5mm/m (which can be achieved by multi roll rolling with a leveling machine); For high-strength steel plates (such as hot formed steel), they need to be preheated to 150-200 ℃ in advance (set according to material characteristics) to reduce material hardness and reduce stamping deformation resistance; Simultaneously control the thickness tolerance of the sheet (such as using cold-rolled steel plates with a tolerance of ± 0.02mm) to avoid stamping depth deviation caused by uneven thickness.
The precision control of precision sheet metal parts is the result of the collaboration of multiple factors such as equipment, molds, processes, personnel, and environment - CNC bending needs to focus on "rebound compensation" and "dynamic parameter control", while stamping forming needs to strengthen "mold design" and "process monitoring".
