To compile the technological process of sheet metal fabrication products, first of all, we need to know all kinds of technical requirements of part drawings; then the drawing surface audit is the most important part of the process planning of parts.
1. Check if the drawing is complete.
2. Graphic view relationship, whether the labeling is clear and complete, labeling size units.
3. Assembly relationships and key dimensions are required for assembly.
4. The difference between the old and new layout.
5. Translation of foreign pictures.
6. Code conversion at the table.
7. Graphic problem feedback and burying.
8. Materials
9. Quality Requirements and Technological Requirements
10. A quality control stamp shall be affixed to the official drawing.
Matters needing attention
Expansion drawings are planar drawings (2D) based on part drawings (3D)
1. The way of deployment should be in harmony with the convenience of material saving and processability.
2. Reasonable choice of clearance and edge-wrapping method, T = 0.2, T = 0.5 of 2-3, long edge-wrapping and short edge-wrapping (door panel type)
3. Reasonable consideration of tolerance shape size: negative difference to the end, positive difference to half; hole size: positive difference to the end, the negative difference to half.
4. Burr Direction
5. Draw sectional views of teeth extraction, riveting, tearing, punching and convex points (bags), etc.
6. Check material, plate thickness, tolerance of plate thickness
7. For a special angle, the radius of bending angle (R = 0.5) should be expanded by trial bending.
8. Highlights should be given in places prone to errors (similar asymmetry)
9. Enlarged maps should be added to places with larger sizes.
10. The place to be protected by spraying should be indicated.