SPECIAL TOPIC : Actuators & Automation
Upstream oil and gas operations process diagram .
Many electric actuators come with failto-position options that automatically return valves to a predetermined position in case of power loss or emergencies . This measure improves safety and prevents possible damage to equipment . They are also equipped with advanced diagnostic features that enable remote monitoring of their conditions , performance , and potential issues . This proactive approach enables early identification and resolution of problems , preventing unexpected failures and associated downtime .
Electric Actuation Solutions
Actuators and controllers are critical components that must deliver higher performance and dependability . Intelligent flow control solutions provide :
Advanced control : Actuators can provide the necessary torques and thrusts while operating at the required speeds for choke and process control valves in upstream applications . In addition , they offer the highest resolution output and modulating duty for accurate pressure and flow rate control .
High reliability : Intelligent electric actuators are designed to provide reliable and repeatable performance in the dynamic and challenging environments of remote oil and gas well sites . They monitor temperature , torque , and voltage to ensure the unit ’ s integrity and operating performance , resulting in a longer product lifespan .
Lower power consumption : Actuation solutions can be energy-efficient and use little electrical power , whether optimizing in-field solar power infrastructure in remote locations or effectively managing an escalator environment with higher-priced available grid power .
Field serviceability : In-field interventions must be rapid and simple , whether carried out remotely , in control rooms , or by physical interaction with the actuator .
Electric actuators are suitable for upstream applications such as gas metering , production trees , processing , saltwater disposal , and gas lift systems . The specific benefits of electric actuation are evident across upstream applications .
Production Trees
A production tree ( often called a Christmas tree ) comprises valves , spools , and fittings essential for regulating the flow of oil or gas from a well . In case of overpressure , a Surface Safety Valve ( SSV ) is a fail-safe / shutdown valve installed at the upper wellbore to execute emergency shutdowns , safeguarding the production tunings . Meanwhile , a production choke valve manages the flow of well fluids and regulates downstream pressure in the flowlines .
Electric actuators are designed for advanced production choke valve operation . They offer non-intrusive operation , easy setup , proportional control , high precision , and low power consumption . They are lightweight , compact , and durable . For example , the Rotork Modular Electro-Hydraulic Solution combines the simplicity of electrical operation with the high torque / thrust and fail-safe fast-action capabilities of hydraulic highpressure control . This solution is used for rotary and linear valve actuation for fail-safe operation of the SSV valve .
Production Processing
Pneumatic diaphragm actuators have traditionally been used to operate control valves in the upstream production process . These actuators primarily use well-stream process gas to power the valve , releasing methane every time the valve is stroked .
Many operators have adopted compressed air as an alternative energy source , deploying air compressor units at production sites . For example , Rotork ’ s electric control valve actuators offer a more advanced and energy-efficient solution . These actuators are suitable for dump valves and back-pressure control valves , commonly used in upstream production processing applications . These actuators not only help achieve net-zero emissions with a solar-powered 24 VDC supply option but also help reduce overall life cycle costs compared to the instrument air actuator alternative .
Gas Metering and LACT Skids
Gas metering and Lease Automatic Custody Transfer ( LACT ) skids connect upstream operations to midstream gathering infrastructure . These systems ensure accurate measurement of natural gas production and oil custody transfer . Compared to upstream processing infrastructure , midstream , pipelines and valves are typically larger and require higher torque / thrust ranges for valve actuation .
Multiple flow control systems work together on a custody transfer metering skid to ensure precise measurement and accuracy . The accuracy and reliability of flow control on metering skids must always ensure safe valve operation . To automate large control valves with highpressure ratings , a high-output actuator such as the CML can be used to deliver increased linear thrust and stroke length .
CVA ( quarter-turn and linear ) are highly accurate and responsive , without the complexity and cost of a pneumatic supply . For LACT valve actuation applications that require a lower modulating duty cycle , the IQT3M Pro , for example , is suitable because it provides a torque range and speed that are well-suited to the requirements . Additionally , it has a duty cycle of 1800 starts per hour .
Gas Lift Systems
When extracting oil from underground wells , a gas lift system is used to lift the fluids to the surface . This system injects high-pressure gas into the well , achieving two crucial effects . Firstly , the injected gas reduces the density of the well fluids , making them flow more easily . Secondly , the gas creates a “ scrubbing ” effect , lowering the pressure at the bottom of the well and aiding the fluid flow .
The effectiveness of a gas lift system relies heavily on a reliable and sufficient supply of high-quality lift gas . A control valve modulates the flow and pressure of the gas injected into the well . For example , the CMA electric actuator is wellsuited for this application . It is designed to operate precisely and continuously , making it suitable for modulation applications like gas lift systems . It is capable of continuously modulating up to S9 / Class D with up to 0.2 % accuracy for accurate and repeatable position control . This does well for use in backpressure lines in gas compressors and throttling valves on gas lift metering skids . This
ABOUT THE AUTHOR ensures that the desired injection flow rates and pressures are maintained .
Saltwater Disposal Systems
Produced water is the largest liquid produced in the oil and gas industry . The volume of water from a well can be up to five times the volume of gas or oil produced from the same well . This water is transported through a gathering line network to recycling tanks or saltwater disposal wells .
The entire system is equipped with multiple actuated valves to ensure the safe and efficient control of produced water flow . Most control valves in water infrastructure require precise control to prevent water hammering . It is essential for back-pressure control valves to operate at high-frequency modulation duty to optimize the performance of water injection pumps . For example , Rotork ’ s CMQ and IQT3M Pro actuators offer adjustable settings for speed , torque / thrust protection , high accuracy , highresolution micro-step movement , and a slow mode for precise positioning .
Conclusion
Advanced automation solutions can help operators reduce emissions , improve process efficiency , and increase production output reliably . Electrifying valve actuation can help reduce the methane emissions produced by oil and gas operations . Selecting low-power solutions suitable for upstream oil and gas processes can help operators achieve emissions reduction targets .
REFERENCE
1 . https :// www . iea . org / reports / global-methanetracker-2023
Chris Hardy is Rotork ’ s Head of Strategy for Oil & Gas . He began his career in the corporate finance team at Endesa Chile , one of South America ’ s largest power generators . After completing his MBA program at the University of Pennsylvania – The Wharton School , he joined the corporate development team at FMC Technologies , the leading supplier of subsea oil & gas production systems . After two years in Houston , he spent 5 years with FMC Technologies in Kongsberg , Norway . Since 2021 , Chris has been working at Rotork as head of strategy for Oil & Gas , helping improve business development and strategy initiatives .
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