Corrosion resistance alloy (CRA) lined pipe is one of the alternative materials for corrosion management in oil and gas application. It is generally more economical compared to CRA clad pipe. However, limited references are currently available regarding performance of CRA lined pipe for high pressure and high temperature (HPHT) pipeline. This paper presents PETRONAS qualification on the suitability of CRA lined pipe for one of its HPHT field. The work focused on the liner and seal weld failure mode due to wrinkling, bending and fatigue cracking during pipeline coating process, offshore installation and operation lifetime. The first stage assessment was conducted using finite element analysis (FEA). Various cases as an effect of pipeline global buckling were considered, including combined pressure, temperature, bending, axial load, cycled between shutdown to normal operating conditions, and effect of griping forces with or without the presence of imperfection. Full scale testing was then performed sequentially simulating full cycle of the pipeline loading, started by thermal loading (coating process), followed by full size four-point bending test (installation case), and lastly full cyclic bending up to maximum lateral buckling strain at design temperature (operation case). Liner gripping force test was then conducted following the full cyclic bending test. Fatigue performance of the seal weld under cyclic loading was also assessed through small-scale low cycle fatigue tests. Both FEA and full scale testing showed that liner pipe was not susceptible to wrinkling at the maximum global buckling loading, even without pressure. There is also indication of residual gripping force even the pipe has gone through full cycle of operation stage. The low cycles fatigue tests also shows high safety factor for the fatigue life. Hence, acceptability of the CRA under actual operating conditions will be higher since bending moments due to buckling occurs while the line is pressurized.

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