API N80 NUE (Non-Ultrahigh Expansion) tubing couplings are engineered to connect N80 grade tubing used in oilfield production strings. They feature:
High-strength alloy steel composition (typically Cr-Mo-V or similar)
Designed for premium connections with controlled expansion tolerance
Compatibility with N80 NUE tubing dimensions and thread profiles
Enhanced resistance to hydrogen sulfide (H₂S), CO₂, and general corrosion
These couplings are critical in maintaining well integrity, preventing leaks, and ensuring the tubing string performs reliably throughout its service life.
API N80 NUE Tubing Couplings Technical Specifications
| Parameter | Typical Range |
|---|---|
| Material | API N80 NUE alloy steel |
| Thread Type | API Premium Connections (NC, IF, or proprietary) |
| Outer Diameter (OD) | Matches tubing OD (e.g., 2 3/8", 2 7/8", 3 1/2") |
| Wall Thickness | As per tubing grade and pressure rating |
| Tensile Strength | 862 MPa (typical for N80) |
| Yield Strength | 621 MPa |
| Max Operating Temperature | Up to 177°C (350°F) for standard N80 NUE |
| Service Pressure | Up to 15,000 psi (depending on OD & wall thickness) |
Actual specifications may vary depending on manufacturer and project requirements. Always verify with Mill Test Certificates (MTC).
API N80 NUE Tubing Couplings Applications
Oilfield Production Strings: Connecting N80 NUE tubing in vertical and deviated wells.
High-Pressure/High-Temperature Wells (HPHT): Suitable for wells with elevated temperature and pressure where conventional N80 Q or P grades may not suffice.
Corrosive Wells: NUE couplings provide superior resistance to sour gas (H₂S) and CO₂ corrosion.
Enhanced Service Life: NUE couplings minimize tubing wear and extend overall well life.
Why Use API N80 NUE Tubing Couplings?
Ensures reliable tubing string connections
Reduces risk of well failure and leakage
Provides enhanced corrosion and wear resistance
Extends service life of production tubing
Selection Guide
When selecting API N80 NUE tubing couplings, consider:
Tubing Compatibility: Ensure OD, wall thickness, and thread profile match tubing.
Pressure & Temperature Ratings: Coupling must handle maximum expected well conditions.
Corrosion Resistance: For H₂S or CO₂ environments, select NUE grade with anti-corrosion treatment if needed.
Certification: Verify API 5CT compliance, MTC, and optional NACE MR0175/ISO 15156 for sour service.
Project Requirements: Check if PSL1 or PSL2 compliance is required for critical wells.
API 5CT N80 Coupling factory
If you are planning a project and need guidance on API N80 NUE tubing couplings, provide:
Tubing OD and wall thickness
Expected operating pressure and temperature
Corrosive environment details (H₂S, CO₂, etc.)
Our engineering team can recommend:
✓ Correct NUE coupling grade
✓ Thread compatibility
✓ Pressure and temperature suitability
✓ Certification and inspection options
API 5CT OCTG Certificate
FAQ
Q1: Can N80 NUE couplings replace N80 Q in a well?
A: Yes, NUE couplings are compatible with N80 tubing, but ensure thread compatibility and well design pressure are considered.
Q2: Are N80 NUE couplings suitable for offshore wells?
A: Yes, NUE couplings are widely used in offshore and onshore high-pressure wells, especially in corrosive environments.
Q3: What testing is performed on NUE couplings?
A: Standard inspections include tensile testing, hardness testing, dimensional verification, and non-destructive testing (ultrasonic, magnetic particle) per API 5CT.