Stainless Steel Coil Tube — TOFD & Phased Array Ultrasonic Tested
Product Overview
Wenzhou Jixing Metal Materials Co., Ltd. supplies premium-grade stainless steel coil tubes manufactured to meet the most demanding international specifications. Our coil tube product line is distinguished by advanced non-destructive testing (NDT) protocols incorporating Time of Flight Diffraction (TOFD) and Phased Array Ultrasonic Testing (PAUT). These state-of-the-art digital imaging technologies deliver superior defect quantification accuracy, positioning our products as the preferred choice for high-integrity industrial and energy applications.
As the global industry shifts toward replacing conventional radiographic testing (RT) with higher-fidelity ultrasonic methods, Jixing Metal has invested in next-generation TOFD and Phased Array systems to ensure every coil tube meets the highest standards of structural integrity and dimensional consistency.
Material & Properties
- Material Grades: AISI 304, 304L, 316, 316L, 321, 310S, 347H, 904L, Duplex 2205, and custom alloy compositions
- Surface Finish: Bright annealed, pickled, polished (2B, BA, No.4, Mirror), or custom as specified
- Mechanical Properties: Tensile strength, yield strength, and elongation compliant with ASTM, EN, and JIS standards
- Corrosion Resistance: Excellent resistance to intergranular corrosion, pitting, crevice corrosion, and stress corrosion cracking
- Temperature Range: Operational from cryogenic temperatures (−196 °C) to elevated temperatures exceeding 870 °C (grade-dependent)
- Hygienic Grade Available: Low carbon versions (304L, 316L) suitable for pharmaceutical and food processing applications
Specifications
| Parameter | Specification |
|---|---|
| Outer Diameter (OD) | 6.0 mm – 114.3 mm (custom sizes available) |
| Wall Thickness | 0.5 mm – 6.0 mm |
| Coil Diameter | 200 mm – 1,500 mm (as required) |
| Coil Length | Continuous coil, typical 30 m – 150 m per coil |
| OD Tolerance | ±0.05 mm (precision grades) |
| Wall Thickness Tolerance | ±10% or ±0.03 mm, whichever is greater |
| Straightness | ≤1.5 mm/m |
| Standard References | ASTM A269, ASTM A312, EN 10216-5, ISO 13970, GB/T 12771 |
| NDT Method | TOFD + Phased Array Ultrasonic Testing (PAUT) |
| Acceptance Criteria | ASME V Section 5 / EN ISO 23906 / ISO 17640 |
Manufacturing Process
- Raw Material Selection: Ingot or billet sourced from certified mills with full chemical composition traceability (mill test certificates provided).
- Hot Rolling / Cold Drawing: Precision forming of seamless or welded coil tube with controlled dimensional tolerances.
- Heat Treatment: Solution annealing to achieve optimal microstructure, eliminate residual stresses, and ensure maximum corrosion resistance.
- Pickling & Passivation: Removal of scale and formation of a protective chromium oxide layer for enhanced surface integrity.
- Precision Sizing: Cold rolling and mandrel drawing to achieve tight OD and wall thickness tolerances.
- Non-Destructive Testing (NDT):
- TOFD scanning for volumetric defect detection with accurate sizing of cracks, inclusions, and laminations
- Phased Array UT for digital beam steering, sectorial scanning, and advanced image reconstruction
- Supplementary eddy current testing for surface-breaking defect identification
- Dimensional Inspection: Automated gauging of OD, wall thickness, straightness, and coil geometry.
- Packaging: Protective coiling with wooden or steel-reinforced packaging to prevent surface damage during transit.
Applications
- Oil & Gas Industry: Heat exchanger tubes, condenser tubes, wellhead tubing, and subsea production systems
- Petrochemical & Refining: Process piping, distillation columns, and reactor internals
- Power Generation: Boiler tubes, superheater coils, and steam generator components
- Food & Beverage Processing: Sanitary heat exchangers, pasteurization coils, and CIP systems
- Pharmaceutical Manufacturing: GMP-compliant process equipment, sterilization systems, and bioreactor components
- Marine & Offshore: Seawater cooling coils, desalination plant heat exchangers, and shipboard piping
- Chemical Processing: Aggressive chemical handling, acid-resistant heat exchange, and reaction vessel internals
- Automotive: Exhaust system components, turbocharger coolant loops, and fuel cell heat management
Quality Certifications & Assurance
Wenzhou Jixing Metal Materials Co., Ltd. maintains rigorous quality management systems to ensure product excellence at every stage of production:
- ISO 9001:2015 — Quality Management System certified
- ISO 3834 — Welding quality requirements compliance
- EN 10204 3.1 — Third-party inspection certificates available upon request
- ASME Section V — NDT procedures qualified per ASME code
- EN ISO 9712 — Level III certified TOFD and Phased Array technicians
- ASNT SNT-TC-1A — Personnel qualification and certification program
- NACE MR0175 / ISO 15156 — Sulfide stress cracking resistance for sour service applications
- Mill Test Reports (MTR) — Full traceability including chemical analysis, mechanical testing, and NDT reports
Unique Selling Points
Digital Imaging Advantage: Our TOFD and Phased Array systems provide superior defect quantification compared to conventional radiographic testing. Digital beam steering and focused array techniques enable precise localization and sizing of internal discontinuities — including hairline cracks, slag inclusions, and laminations — that may be missed by traditional RT methods.
- Higher Defect Detection Sensitivity: TOFD offers improved near-wall and far-wall defect detection capability with no film grain noise interference
- Reduced Inspection Time: Phased Array sectorial scanning replaces multiple single-element UT probes, cutting inspection cycle time by up to 50%
- Permanent Digital Records: All NDT data is stored digitally, enabling traceability, audit readiness, and repeatable acceptance decisions
- Environmental & Safety Benefits: Eliminates ionizing radiation exposure associated with radiographic testing, ensuring a safer working environment
- Industry Trend Alignment: Our NDT capabilities align with the global trend of replacing radiographic testing with advanced ultrasonic methods in high-end projects, including nuclear, aerospace, and deepwater oil & gas
- End-to-End Traceability: From raw material certification through final NDT release, every coil tube is fully traceable to its production batch
By combining premium stainless steel metallurgy with best-in-class TOFD and Phased Array ultrasonic testing, Wenzhou Jixing Metal Materials Co., Ltd. delivers coil tube solutions that provide maximum confidence in structural integrity, corrosion performance, and long-term service life.