Case Overview
A subsea-equipment and offshore-processing supplier was qualifying supply of two demanding material groups: Inconel 625 pipe for subsea flowlines exposed to sour produced fluids, and CuNi heat-exchanger tubes for seawater cooling. The previous supplier could not consistently provide corrosion-related chemistry documentation, risking requalification against the operator’s material requirements.
DZX qualified with Inconel 625 pipe including complete chemistry and mechanical documentation aligned to sour-service requirements, and CuNi tubes with verified chemistry for seawater service. One auditable source covered both subsea and topside systems.
This case summarizes the application requirements, materials supplied by DZX and delivery value. For case-specific technical data, please contact our engineering team.
| Item | Details |
|---|---|
| Client Profile | Subsea-equipment and offshore-processing supplier |
| Project Scale | Flowline and heat-exchanger projects, ongoing supply |
| Application | Subsea flowlines, seawater cooling and topside piping |
| Materials Supplied | Inconel 625, CuNi alloys and Monel 400 |
| Supply Forms | Pipe, tube, plate and wire |
| Lead Time | Mill batches: 4-6 weeks; standard stock sizes: 1-2 weeks |
| Project Country | Norway |
| Project Year | 2024 |
Our Solution
The supplier’s qualification process required three assurances:
- Sour-service documentation: subsea flowline materials had to meet operator requirements, with documented chemistry and hardenability control for each heat.
- Seawater corrosion performance: seawater heat-exchanger tubes needed erosion-corrosion resistance at design flow velocities, with verified Cu/Ni composition.
- One audit, two systems: the customer wanted subsea and topside materials under one quality system to avoid duplicate supplier audits.
DZX delivered both material groups under one auditable system:
Inconel 625 pipe included complete chemistry and mechanical documentation, with chemistry control aligned to sour-service material requirements. CuNi tubes were supplied as CuNi10Fe and CuNi30Mn with verified chemistry for seawater service; Monel 400 covered valve and pump internals. Every batch included chemistry, mechanical and corrosion-related documentation in the customer’s qualification-file format.
| Material | Representative Grades | Key Properties | Available Forms |
|---|---|---|---|
| Inconel | 625 | Corrosion resistance and sour service | Pipe, tube and plate |
| CuNi alloys | CuNi10Fe, CuNi30Mn | Seawater erosion-corrosion resistance | Tube and plate |
| Monel | 400 | Valve and pump internals | Bar, plate and wire |
View Inconel Alloys → | View Copper-Nickel Alloys → | View Monel Alloys →
Subsea flowlines and linings
Seawater heat-exchanger tubes
Corrosion-resistant fasteners and fittings
Technical Specifications
Key technical parameters agreed before production. Contact us for grade-specific datasheets and tolerance-verification reports.
| Parameter | Agreed Specification | Verification Method |
|---|---|---|
| Inconel 625 pipe | To drawing (e.g. 168.3 mm OD × 10.97 mm wall) | Micrometer + ultrasonic wall-thickness measurement |
| Chemistry documentation | Complete heat chemistry for every batch | Chemical analysis report |
| CuNi composition | CuNi10Fe / CuNi30Mn to ASTM B151 | Batch chemical analysis |
| Seawater service | Erosion-corrosion resistance at design flow velocity | Chemistry + surface verification |
| Sour-service alignment | To operator material requirements | Documented chemistry and hardenability |
Each supplied batch includes a quality inspection certificate with chemical analysis, meeting the applicable standard for each grade.
| Material | Applicable Standards |
|---|---|
| Inconel 625 | ASTM B444, B705 |
| CuNi alloys | ASTM B151, B171 |
| Monel 400 | ASTM B164, B127 |
| Quality System | Quality inspection certificate including chemistry and mechanical properties |
Delivery and Quality Support
- Fast delivery: Sample and production lead times follow the project schedule; standard grades and sizes can be dispatched promptly from stock.
- Quality traceability: Every batch includes material certificates and inspection reports, with full heat and batch traceability.
- Technical support: Responsive support covers pre-sale material selection, drawing review and post-sale processing advice.
- Ongoing service: Regular follow-up after delivery tracks performance and addresses feedback promptly.
Customer Feedback
- Qualification risk eliminated: documented chemistry and hardenability closed sour-service requalification gaps
- Seawater reliability: verified CuNi chemistry ensured erosion-corrosion resistance at design velocity
- One audit, two systems: subsea and topside materials supplied under one quality system
- Stock coverage: standard sizes shipped in 1-2 weeks for fabrication continuity
- Mill-level traceability: heat numbers and full batch documentation
- Three alloy families: Inconel, CuNi and Monel coordinated by one manufacturer
Our Capabilities
Jiangsu DZX Technology Co., Ltd. (Changzhou DLX Alloy) was founded in 2016. Its core team has worked in the field since 2002, with 24 years of precision-alloy R&D and production experience, operating a self-owned 12,000-square-meter modern factory with an ISO9001 system covering three inspection stages. Annual alloy output exceeds 1,200 tonnes, serving 1500+ business customers worldwide. The company operates integrated melting, drawing, annealing and precision-machining workshops, supporting volume customization of strip, wire, tube and bar. Every batch includes a chemical analysis report (MTC) for full delivery-quality traceability.
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