Abstract
Formation sand production is one of the major production challenges in most of the mature fields in Malaysia. Often, failure in primary sand control equipment requires the operators to adopt through-tubing sand screens as remedial sand control. Due to the erosion prone nature of the thru-tubing metallic sand screen, operators are forced to impose limitation on the production rate coupled with stringent surface sand monitoring system to avoid surface flow line leakage and loss of primary pressure containment. Therefore, to seek a more robust technology than conventional metallic screens, alternative technology with through-tubing ceramic sand screen (TTCSS) has been considered with the idea of higher durability and resistance against erosion. This paper will discuss the performance and lessons learnt from the application of through-tubing ceramic sand screen throughout several mature fields in Offshore East Malaysia.
Over the past two years, there have been about twenty-five TTCSS installations in Offshore East Malaysia. Seven pre-mature failure cases were observed, where sands were produced to the surface and even caused leaks on the flow line. The average effective production period for all TTCSS across all the fields ranges from 6 to 11 months. Teardown investigations have been conducted to diagnose the failure root cause.
Most failed TTCSS exhibited similar failure patterns at the end caps, which house the spring compensator. Failure to stop the flow through the end caps led to substantial erosion at spring compensator and base pipe, inducing large flow path for sand production to the surface. Other than the design failure, application failure was observed at the ceramic rings due to their brittleness.
Computational fluid dynamic simulation and laboratory testing have been conducted at the higher incremental production rates to support the observations from teardown inspections, refine the hypothesis of failure mechanism and enable an incremental design change to be modified into TTCSS. In order for TTCSS to be one of the competent candidates for remedial sand control, new improved standard design of TTCSS with strengthened end cap area will be studied to prevent similar failure.
