Blank relative thickness

(T = 100 t/D)

2 - 1.5

1.5 - 1.0

1.0 - 0.6

0.6 - 0.3

0.3 - 0.15

0.15 - 0.08

First ultimate drawing coefficient m₁

0.48 - 0.50

0.50 - 0.53

0.53 - 0.55

0.55 - 0.58

0.58 - 0.60

0.60 - 0.63