Principles For Stamping Process Sequencing

• Process Logic Priority

1.   Perform punching before forming (e.g., pierce pilot holes before bending or deep drawing).
2.   Progressive forming (e.g., deep drawing for complex shapes).
3.   Local features (flanging, notching) should precede final forming.

• Efficiency Maximization

1.   Combine operations using compound dies (e.g., blanking + piercing in one stroke).
2.   Optimize progressive dies for continuous production (e.g., pilot holes → blanking → bending → cutoff).
3.   Minimize handling and repositioning to reduce errors.

• Quality Assurance

1.   Critical dimensions should be finalized in later stages (e.g., sizing/coining for precision).
2.   Control springback with compensation or post-bend correction.
3.   Maintain consistent burr direction (e.g., all burrs facing downward).

• Cost & Resource Balance

1.   Simplify tooling for low-volume production; use multi-stage dies for high volumes.
2.   Optimize material utilization (nesting, scrap recycling).

• Example Process Flow (Stainless Steel Bracket):

  Blanking → 2. Piercing → 3. Bending → 4. Sizing → 5. Trimming → 6. Surface Treatment

• Key Considerations:

1. Avoid interference (e.g., bend sequencing to prevent tool collisions).
2. Ensure consistent locating (e.g., pilot holes or edge stops).
3. Match press capacity with forming forces (e.g., deep drawing tonnage calculation).

Common Mistakes & Fixes:

1. Issue: Deformed holes after bending.
2. Solution: Pierce holes before bending or use protective pads.
3. Issue: Poor feeding in progressive dies.
4. Solution: Add guide pins or adjust feed pitch.

By following these principles, manufacturers can achieve higher precision, lower scrap rates, and optimized production costs.