Condition and Performance Analysis of a Subsea BOP Control System Pressure Regulator

Abstract

Presented in this paper is a model-based approach for performance and health monitoring of a double spool blowout preventer (BOP) pressure regulator. Governing equations of the pressure regulator are derived based on mathematical and functional relationships. The relationships are carried to a simulation environment. Same approach is followed to generate the model of an annular preventer control circuit from the hydraulic power unit to the preventer itself. The nominal performance the regulator during an annular preventer closing event and effects of internal leakages are shown via simulation. Model-based condition and performance monitoring techniques are developed to detect regulator internal leakages and regulator instabilities. The methods are demonstrated over a dataset obtained from a deepwater BOP. The results show that the leakage detection method can differentiate between a leaking and non-leaking regulator within the same BOP, and that regulator instabilities can be detected with the given sensor set and data acquisition capabilities.

Oscillating Back Pressure Regulator (OBPR) for High-Pressure Core Flooding

“…Several studies use pressure response to analyze a regulator's performance [12,13,14,15,16,17,18]. To understand the initial pressure response of the OBPR, the model was compared with the pressure response of two commercial BPRs that are used for similar applications.…”

Subsea blowout preventer (BOP): Design, reliability, testing, deployment, and operation and maintenance challenges

“…[14] Use of qualitative risk assessment (QRA) to prioritize areas of greater reliability concern [15] Evaluating failure statistics and testing time consumption for 83 GOM wells in 400-2000m water depths [16] Positive effects of inspection and testing for high-pressure high-temperature (HPHT) BOPs [17] Evaluation of downtime caused by BOP failures and testing [18] DW BOP reliability and failure rate evaluation. BOP failure calculations based on drilling cycle [19] Reliability analysis across different activity phases and operating conditions for subsystems [20] BOP control system reliability relative to maintenance goals [21] Risk management of surface blowout preventers (SBOPs) in DW and comparison with SSBOPs [22] New hybrid electro-hydraulic control system development for DW BOP applications [23] Limitations in accumulator design [24] Comparing risks of different configurations on DP rigs [25] Design challenges and solutions for BOPs (ram preventer in particular) [26] Experience with SBOP and its advantages [27] Automatic monitoring of BOP state to improve maintenance Post-Macondo [12] Forensic investigation of the Macondo BOP [28] Detailed DW SSBOP reliability evaluation and kick data for 259 wells in the GOM OCS [29] Risk assessment options for operating different BOP configurations (SSBOP and SBOP with SID) [30] Risk analysis of drilling in DW with considerations to leakage in ram preventer in particular [31] Condition and performance monitoring of a pressure regulator employed on deepwater BOPs…”