Performance Test of N80 Expandable Casing
A more comprehensive,systematic experimentical ground tests of the expansion process of expandable casing were performed. In the tests, 6 5 1/2"N80 casings were selected, of which five had been carried out expansion tests , another one casing was used to test the collapse strength , not been expanded. In the course of the tests,some important parameters of the expandable casing were measured before and after expansion,including the inner and outer diameter, wall thickness, ovality, wall thickness of inequality and the axial deformation, etc..These data provide a reliable basis for the mechanism research of the N80 casing expansion. After expansion tests, these six casing pipes had been performed the collapsing tests in Xi'an Tubular Goods Research Institute of CNPC.The test results show that after expansiong the collaps strength of expandable casing get decreased compared with unexpanded casing which provides a practical basis and reference for the design of expandable casing.
Guojun Zhang and Jessica Xu
B. Yang and D. Z. Zeng, "Performance Test of N80 Expandable Casing", Advanced Materials Research, Vols. 160-162, pp. 1095-1099, 2011