Abstract:

Sand production will severely impact the perforated casing mechanical properties during well production,which can damage the casing.The 3D mechanical finite element model of perforated casing is established at the sanding formation.The mechanical characteristics of casing are analyzed with the Ansys finite element software.The analysis indicates that the perforated casing mechanical properties of sanding formation change obviously,the collapsing strength of casing decreases at perforation location,but the max stress generates there.Under even load,the casing stress is parabola relation with sand production height,sand production rate should be away from the critical sand production height by increasing or decreasing sand production rate in order to reduce the casing stress.Under un-even load,the cavity height increases with the sand production rate increases,and the casing stress reduces gradually.Hence the sand production rate should be increased in order to enhance the casing collapsing strength,and prolong the service life of casing.

Key words: sand production rate, perforated casing, finite element, cavity height, collapsing strength