Case Study Integrity injection valves reduce capital expenses for injection wells
Prevented reservoir backflow without requiring an external control system in West Africa and Brazil deepwater wells.
Integrity INJ subsurface safety valve
Compact, modular design for a wide range of injection applications
Overview
Applications
- Water and gas injection wells
- Sweet to severely corrosive environments
Benefits
Leverage enhanced valve performance and durability for injection
The large-bore design facilitates more efficient flow. This feature is especially beneficial in high-flow injection applications, enhancing overall valve performance.
Integrity INJ valve maximizes reliability by minimizing potential leak paths. An optional coating is available for selected internal surfaces to minimize solids deposition, which can impede flow and negatively impact performance over time. The number of seals is minimized, reducing potential points of failure and enhancing the valve’s durability. Additionally, the optimized flow path and clearance between sliding components ensure smooth operation and reduce wear. These features collectively contribute to the valve’s robustness and longevity.
No surface control is required, simplifying installation and operation.
Features
A temporary lockout mechanism holds the valve open to facilitate installation and commissioning. During the life of the well, a retrievable choke mechanism enables adjusting orifice sizes to suit changing injection rates. These features and the cost-effective, compact modular design ensure that the valves are both efficient and adaptable.
The valves exceed API or ISO specifications at the time of qualification. Metal-to-metal seals with proprietary locking and sealing threads support reliable pressure integrity.
FAQs
How does the Integrity INJ valve work?
The valve is initially closed. Injection flow generates a pressure drop across the orifice in the retrievable choke mechanism. This differential pressure acts on the piston of the flow tube, causing it to move downward and compress the power spring to open the valve. In the open position, the flapper and seat system are isolated from the injection flow.
When injection stops, the pressure differential across the orifice decreases and the force of the spring lifts the flow tube. This upward movement permits the torsion spring on the hinged flapper to move the flapper into the flow stream and close against the seat, preventing injected fluid from flowing back from the well.
Can the valve be temporarily locked open during interventions?
Yes, a lockout mechanism enables a simple slickline procedure to temporarily shift the valve into the fully open position. The lockout tool locates in the landing nipple profile and positions a set of shifting dogs in a specifically designed area of the lower flow tube. Activation of the temporary lockout tool shifts the lower flow tube down and away from the upper flow tube, moving the flapper closure mechanism out of the valve bore.
What is the process for adjusting the valve activation pressure?
The size of the orifice in the choke assembly is selected to ensure that the differential pressure created by the injection fluid produces enough force to operate the valve. The orifice is secured in a section of the flow tube. If the orifice size needs to be altered because of an injection flow rate change, the choke assembly can be easily retrieved by using a simple slickline procedure, enabling installation of the correct orifice, followed by reinstallation in the safety valve.
How are Integrity INJ valves qualified?
The valves are validated to API Spec 14A V3, but their performance exceeds the certification requirements.
Flapper leakage: API Spec 14A allows leakage up to 5 ft3/min. The acceptance criterion for Integrity INJ safety valve flapper systems is bubble-tight performance.
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