Following up on my parallelism comment — here's more detail on the door ring motion profile since I've done a few of these now.
Door rings are one of the hardest parts to get right on a servo press because of the geometry. You've got a deep draw section, a stretch flange section, and a trim section all in one die, and each one wants a different forming speed.
What we ended up with on a 1180 MPa CP steel door ring (1.4mm, ~1100mm long):
Phase 1 — Fast approach: 350mm/s down to 15mm above first contact. Nothing special here.
Phase 2 — Pre-contact decel: ramp down to 80mm/s over 15mm. This is where most people don't decelerate enough. If you hit the blank at 200mm/s, the initial impact shock causes micro-cracking at the draw radius that you won't see until 50K parts later when those cracks propagate into splits.
Phase 3 — Initial draw (first 40% of draw depth): 40mm/s. The material is flowing into the die cavity and the blank holder is doing most of the work controlling wrinkles. Slower is better here.
Phase 4 — Deep draw (40-90% of depth): ramp up to 60mm/s. By now the flange has shrunk enough that wrinkling risk is lower, and the material is work-hardened enough to resist tearing at slightly higher speed. This is where you recover cycle time.
Phase 5 — Final form + BDC dwell: decel to 25mm/s for the last 10%, then 80ms dwell. The dwell lets the press frame deflection stabilize and gives the material a moment to stress-relieve slightly. On UHSS this dwell is critical — without it, springback was 3.2mm. With 80ms dwell, springback dropped to 1.8mm. Still needed a compensation die, but 1.8mm is manageable.
Phase 6 — Return: 400mm/s. Use the fastest return your press allows. On a 1200mm door ring die, the stripper force is significant — make sure your return tonnage capacity handles it.
Total cycle: about 2.8 seconds stroke-to-stroke at these speeds. On a mechanical press doing the same part, you'd be at maybe 2.2 seconds but with 3x the scrap rate.