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This case study examines the conversion of a Tier 1 automotive supplier's door inner panel line from conventional mechanical press to servo press.
## Background
The supplier was producing door inner panels from 0.8mm DP600 dual-phase steel on a 600-ton conventional mechanical press at 8 SPM. Key challenges: **4.2% scrap rate** due to springback variation, frequent die cracking, and inability to run thinner gauges.
## Servo Press Selection
A 600-ton servo press with link-drive mechanism was selected. Key criteria: high torque at BDC for DP600 forming, programmable dwell capability.
## Implementation
Die tryout took 3 weeks. Forming speed was reduced from 180 mm/s to 60 mm/s in the critical forming zone. A 0.2-second dwell was added at BDC. Approach speed was increased to 350 mm/s to maintain productivity.
## Results After 6 Months
| Metric | Before | After |
|--------|--------|-------|
| Scrap rate | 4.2% | 0.8% |
| Die life | 150k hits | 400k hits |
| Cycle rate | 8 SPM | 8 SPM |
| Material gauge | 0.8mm DP600 | 0.7mm DP780 |
| Energy vs hydraulic backup | baseline | -38% |
## ROI Calculation
- Annual savings: $317,000
- Press investment premium: $380,000
- **Simple payback: 14 months**
## Lessons Learned
The biggest challenge was retraining operators to think in terms of motion profiles rather than fixed press parameters. Invest in training.