The onset of buckling does not necessarily mean pipe failure. The acceptability of buckled casing must be assessed in two ways, i.e. the resulting stresses in the casing wall, and the access through the buckled casing for drilling and production tools.
Stresses resulting from buckling must be added to those existing in the casing prior to the onset of buckling.
However, post-buckling analysis is complex and the use of computing tools for detailed analyses is required. The advanced theories for the plastic buckling mode, which should be applied when the compressive stresses are larger than half the yield strength, should be studied in cooperation with a Structural Engineering company.
A distinction is made between the helical buckled casing and the non-helical buckled casing. However, it should be understood that the non-helical buckling mode occurs prior to the helical buckling mode.