PRCI PR-185-9211

L51757e

Edison Welding Institute

Need: While full-encirclement sleeves have been routinely used to repair damaged or corroded sections of operational pipelines, it is not well understood how the increased localized stiffness due to the sleeve, affects the deformation capacity of the sleeved section when it is subsequently subjected to complex loads arising from superimposition of ground movement generated forces on operating pressure.

Result: For this study deformation capacity was expressed as the critical buckling curvature of the full-contact sleeve and the parameters studied, in addition to internal loading, were the influence of D/t ratio, sleeve length, sleeve type, pipe grade, and temperature differential on critical buckling curvature. Elastic plastic finite element analyses (FES) were used to develop provisional guidelines concerning the deformation capacity of both sleeved and unsleeved pipes. Two full-scale bend tests were performed to validate the FEA model.

Benefit: The test results indicated that the provisional guidelines were sufficiently accurate to predict imminent plastic collapse.

Product Details

Published:

12/26/1997

Number of Pages:

285

File Size:

1 file , 11 MB