You must log in to edit PetroWiki. Content of PetroWiki is intended for personal use only and to supplement, not replace, engineering judgment. SPE disclaims any and all liability for your use of such content. A valve located at the tree, above the master valve, on the flow line.

You must log in to edit PetroWiki. Content of PetroWiki is intended for personal use only and to supplement, not replace, engineering judgment. SPE disclaims any and all liability for your use of such content. A sharp, sometimes very high force and pressure load that is created when a valve is closed too rapidly in a flowing stream. The major force occurs behind the valve.

You must log in to edit PetroWiki. Content of PetroWiki is intended for personal use only and to supplement, not replace, engineering judgment. SPE disclaims any and all liability for your use of such content. Any of several valves: plug, gate, butterfly, needle, etc., used in oil field operations.

You must log in to edit PetroWiki. Content of PetroWiki is intended for personal use only and to supplement, not replace, engineering judgment. SPE disclaims any and all liability for your use of such content. Generally a downhole valve that, when opened, permits circulation.

You must log in to edit PetroWiki. Content of PetroWiki is intended for personal use only and to supplement, not replace, engineering judgment. SPE disclaims any and all liability for your use of such content.

Summary

In this paper we investigate stability for severe slugging including self-lifting by using a stability solver. The stability solver is a tool in which a numerical linear stability analysis is applied to a mathematical model for a two-phase flow in a pipeline-riser system. The self-lifting approach is interesting because different configurations for the stationary state may occur. Depending on the system parameters, experiments show that two unstable regions may exist. Several parametric analyses are realized to evaluate the influence of self-lifting and to determine an optimal operational condition. Stability maps for severe slugging are built, and experimental data from literature are included, showing a very good agreement; in particular, the two unstable regions were satisfactorily predicted by the stability solver.

In the drive for remote operations, reducing operator costs and reducing emissions and CO2, digitalization of sensors and control systems is imperative. To date, valves on wellheads and trees have predominantly been controlled by hydraulic actuators that are not ideally suited for fully remote operations.

A new, innovative, electric actuator has been developed under a Joint Industry Project (JIP) by Equinor, Baker Hughes and TECHNI. This actuator is designed for fail-safe, critical operations offshore and is subject to stringent safety design requirements. The key motivation is reducing CAPEX and OPEX for offshore installations, while increasing availability of wells while providing improved monitoring and condition based, predictive maintenance.

The electric actuator that was developed in the program has a patent pending fail-safe mechanism with extremely fast closing time (less than 1 second) to ensure well containment during critical situations. The actuator is designed to be a drop-in replacement for NoBolt™ CHA actuator solutions and is suitable for most standard wellhead and tree designs, sizes and pressure ratings. In the new all-electric design, a multitude of sensors in combination with an OPC-UA architecture, enables data-driven insights from the systems in operation.

The program was started in 2017 and has resulted in a system at Technology Readiness Level (TRL) 4 (on 0 to 7 scale) with TRL 5 testing planned in 2020 yielding it ready for field installation.

ADNOC Offshore started-up full field gas-lift activation for the first time in 2020. This major step will unlock field's potential by increasing reservoir withdrawal and increasing wells life by mitigating water production / breakthrough. This paper details the successful application of gas-lift from design during appraisal phase and early production stage to full field implementation. Fit for purpose design was implemented through multi-disciplinary studies and work. A strong change management in operating philosophy was requested to take onboard all stakeholders: Field development, Field Operation, Wells operation, Drilling and completion. Following appraisal and early production phases on a green field, wells design was optimized to ensure proper activation in most of the producers (two over three reservoirs developed). Due to full field development phasing, the first 30% of the wells completion were designed based on early production phase data. Before full field commissioning started, in well gas-lift valves were designed and installed, integrating all the dynamic information gathered during natural flow production. Valves change out was performed with the highest HSE standards, and taking into account full field development timing in order to reduce downtime and therefor maximize production. As gas-lift is new in the operating company, a strong change management was required: operating with gas-lift by field operation team, Completion design, Drilling and Gas-lift Production with SIMOPS. Gas Lift implementation will ensure the future oil production of the field as water injection and production will increase. Gas-lift practice implementation led to modifying the operating company's rules in multiple and deep aspects:

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Improve field team competencies in handling high pressure gas-lift system,

As a first achievement, one well under reservoir integrity issue (low productivity due to reservoir collapse) was re-activated and production of existing wells was increased of several thousands baril. Further increase in production is expected in the following months as implementation is deployed to all required wells.