Hu Lin Pipe, a leading manufacturer of pipe fittings and flanges, has successfully completed and shipped its second order of Hastelloy C-276 (UNS N10276) flanges and pipe fittings for a CNOOC (China National Offshore Oil Corporation) offshore platform project.
This repeat order demonstrates the client’s confidence in Hu Lin Pipe’s product quality, manufacturing precision, and commitment to delivering materials that meet the stringent requirements of offshore marine environments.
The Offshore Corrosion Challenge
Offshore oil and gas platforms operate in one of the most corrosive environments on Earth:
- Seawater immersion — high chloride content (19,000+ ppm) accelerates corrosion
- Salt spray atmosphere — constant exposure to moisture and salt deposition
- Temperature cycling — thermal stress from ambient to process temperatures
- Galvanic corrosion — dissimilar metal contact in marine settings
- Microbiologically influenced corrosion (MIC) — bacteria in seawater
Standard stainless steels (304/316) cannot withstand these conditions for the 20-30 year design life of offshore platforms. This is why Hastelloy C-276 is specified for critical piping systems.
Why Hastelloy C-276 for Offshore Platforms?
Hastelloy C-276 is a nickel-molybdenum-chromium alloy (Ni-Mo-Cr) engineered for exceptional corrosion resistance in aggressive environments:
Material Properties
| Property | Specification |
|---|---|
| UNS Number | N10276 |
| W.Nr. | 2.4819 |
| Composition | Ni 57%, Mo 16%, Cr 16%, Fe 5%, W 4% |
| Density | 8.89 g/cm³ |
| Tensile Strength | 690 MPa (min) |
| Yield Strength | 276 MPa (min) |
| Elongation | 40% (min) |
Corrosion Resistance
✅ Pitting Resistance — Excellent in chloride environments (PREN > 65)✅ Crevice Corrosion — Superior resistance in seawater and brine✅ Stress Corrosion Cracking — Highly resistant to chloride SCC✅ Oxidizing & Reducing Media — Performs well in both conditions✅ Temperature Range — -196°C to 400°C (-320°F to 750°F)
Order Details
Flanges (ASME B16.5 / ASTM B564)
- Weld Neck Flanges (WN) — for high-pressure process piping
- Blind Flanges (BL) — for isolation and future expansion
- Socket Weld Flanges (SW) — for small-bore instrumentation lines
- Pressure Classes: Class 150, 300, 600, 900, 1500
- Size Range: 1/2″ to 24″ NPS
Pipe Fittings (ASME B16.9 / ASTM B366)
- 90° and 45° Elbows — long radius (1.5D) and short radius (1.0D)
- Equal and Reducing Tees — for branch connections
- Concentric and Eccentric Reducers — for size transitions
- Pipe Caps — for end closures
- Size Range: 1/2″ to 24″ NPS
- Wall Thickness: Sch40, Sch80, Sch160, XXS
Quality Documentation
✅ Mill Test Certificates (MTC) — EN 10204 3.1 with full chemical and mechanical properties✅ PMI Testing Reports — Positive Material Identification for every heat✅ Dimensional Inspection Records — per ASME B16.5 and B16.9 tolerances✅ Third-Party Inspection — SGS/Bureau Veritas available per client request
Why CNOOC Chose Hu Lin Pipe — Twice
1. Material Authenticity & Traceability
We source Hastelloy C-276 from certified mills with complete traceability. Every heat number is documented, tested, and verifiable — critical for offshore safety cases.
2. Manufacturing Precision
Our CNC machining centers ensure dimensional accuracy within ASME tolerances. Precise fit-up reduces installation time and welding costs on the platform.
3. Quality Consistency
A second order is the strongest validation of quality. Our ISO 9001:2015 certified processes ensure every shipment meets the same high standards.
4. Technical Understanding
We understand offshore requirements — NORSOK M-650, API 6A, and project-specific specifications. Our engineering team provides technical support throughout the project.
5. On-Time Delivery
Offshore projects operate on tight schedules with expensive vessel time. We deliver when promised, every time.
Offshore Industry Applications
Hu Lin Pipe’s Hastelloy C-276 products serve critical offshore systems:
| Application | Function | Why C-276 |
|---|---|---|
| Seawater Injection | Pressure maintenance | Chloride resistance |
| Firewater Systems | Safety-critical | Reliability under all conditions |
| Chemical Injection | Corrosion inhibition | Acid resistance |
| Produced Water | Water treatment | Mixed corrosive media |
| Subsea Piping | Well flowlines | Long-term seawater exposure |
