Entry Angle

For larger drawing ratios, there is a straight section between the two deflection radii r_M and r_St , which is conically inclined at an angle α to the horizontal to reduce the bending stress.

For different materials the entry angle is29

• Stainless steel α = 35°
• Aluminum α = 45°

If d₁ /s₀ > 100, the lead-in chamfer is α = 38°.

If d₁ /s₀ is determined between 50 and 100, the lead-in chamfer α = 45° is selected.28

The optimal entry angle α is given in27 as 45°.