The mechanics criterions of deforming WHA interior and surface crack were derived from deformation body plasticity zone speed field distribution,and two sorts of mechanics criterions curve were plotted during analyzing high density WHA deformation defects.

In the light of the status that there are caustic faults in the oil well tubing and there are not effective inspections, in this paper the plane roundness fault model of the is studied, and the magnetic leakage flux distributing model at the direction of the normal of the roundness fault is proposed.

Tension-leveling can eliminate shape defects effectively, so as to increase the quality of strip.

Tension-leveling line now is widely used in high quality aluminium rolling production, because it can eliminate shape defects such as wave and warp effectively.