UDT Tubing Retrievable Reverse Flow Check Valves
Backflow of fluids into the annulus can damage casing, reduce the life of gas lift valves, and possibly create unsafe wellbore conditions.
UDT tubing retrievable reverse flow check valves
UDT tubing retrievable reverse flow check valves are attached to the bottom of tubing retrievable gas lift valves that do not have an integral check valve to prevent fluid backflow through the valves. Backflow of fluids into the annulus can damage casing, reduce the life of gas lift valves, and possibly create unsafe wellbore conditions.
Operations
When the gas lift valve is open, the injection or casing pressure on the check valve is greater than the downstream (typically tubing) pressure. The higher upstream pressure depresses the spring loaded dart, allowing the injection gas to flow through the check valve and into the production tubing. If the downstream pressure is greater than the upstream pressure, flow across the check dart causes the dart to seat, preventing backflow. Reverse flow check valves have dual seals for adding protection against backflow. When the tubing pressure comes in contact with the bottom of the check, the elastomeric seal is established. As the differential pressure increases, a metal to metal seal is formed for additional protection.
Special Features
- Field proven design and operation.
- Reverse flow check valve fitted at the bottom to prevent backflow from tubing to casing.
- Manufactured from a variety of premium grade materials to provide corrosion and erosion resistance for the intended application. Stainless steel or Monel options are typically utilized for the outer and main body components.
- Reverse flow check valves have dual seals for added protection.
Stainless steel dart with a large flow bypass. - Inspection and testing as per the stringent requirements of erstwhile API 11V1 & API 19G2 specifications.
Key features of all UDT Swift Connectors
Self-aligned & no cross threading
Strength characteristics higher than casing pipe.
Make-up in 4 turn from stab to full make up
4 turn rotation make-up prevents connector back-off
Suitable for piling/jetting.
Visual indication of make-up
Low torque make-up with rig tongs.
Preloaded for fatigues.
High-pressure sealing.
Reversible and reusable
ENGINEERING DATA FOR TUBING RETRIEVABLE REVERSE FLOW CHECK VALVES
