Gas and Water Permeation in Flexible Pipes

Abstract

A test program has been performed to obtain the permeation coefficients for methane, carbon dioxide and water in PVDF. Small-scale tests showed that water is transported through the PVDF inner sheath of the flexible pipes, and into the annulus. A large-scale test was carried out to verify the small-scale test results. It was performed in a 2″ flexible pipe with length 3 m. The bore temperature and pressure were 100°C and 50 bar, respectively. The pipe was submerged in cold water in order to get a correct temperature gradient in the pipe. The test showed that the annulus of flexible pipe with PVDF inner sheath would become water wet due to permeation, depending upon the bore and annulus conditions.

Permeation Damage of Polymer Liner in Oil and Gas Pipelines: A Review

“…It was proved by a large-scale test at 100 °C and 50 bar in the presence of CH 4 and CO 2 gases. The permeation of CO 2 is more than CH 4 [ 78 ]. IFP and Technip provided a solution to obstruct H 2 S permeation.…”