Maximum d/t

(standard size ratio)

Average wall thickness (mm)

Average outside diameter (mm)

Ovality (%)

Wall thickness nonuniformity (%)

Residual stress (mpa)

Yield minimum value (mpa)

Section number

Intact tubing (according to the collapse morphology in the middle of the tubing to collapse the choice of section 5 geometry size)

13.49

6.59

88.93

0.38

5.16

−140.5

720

5

Plastic collapse compressive strength (mpa)

Kt ultimate collapse strength (mpa)

93.1

97.7

Extrusion strength of collapsing tubing (evaluation)

12.5

7.14

89.32

0.45

9.1

−140.5

705

/

Plastic collapse compressive strength (mpa)

Ktultimate collapse strength (mpa)

103.5

104.76