Stainless Steel Coil Tube — Wenzhou Jixing Metal Materials Co., Ltd.

Product Overview

The Stainless Steel Coil Tube (Product No. 1651) manufactured by Wenzhou Jixing Metal Materials Co., Ltd. is a high-performance, continuous-form tubular product supplied in coil configuration for downstream processing convenience. Engineered to meet the rigorous demands of modern industrial applications, this coil tube offers superior corrosion resistance, mechanical integrity, and dimensional precision. The coil format eliminates the need for field welding of short-length sections, reducing joint failure points and improving overall system reliability. This product line is designed for applications requiring seamless, hygienic, or chemically resistant piping solutions across multiple industries including food and beverage processing, pharmaceutical manufacturing, chemical engineering, and heat exchanger fabrication.

Material & Properties

Wenzhou Jixing Metal Materials Co., Ltd. offers coil tubes fabricated from a range of austenitic and duplex stainless steel grades, each selected to optimize performance for specific service conditions:

• Austenitic Grades: SUS304 (UNS S30408), SUS316L (UNS S31603), SUS321 (UNS S32100), SUS316Ti (UNS S31635) — offering excellent general corrosion resistance, weldability, and formability.
• Super Austenitic Grades: SUS904L (UNS N08904), SUS254 SMO (UNS S31254) — providing exceptional resistance to pitting, crevice corrosion, and high-temperature oxidation.
• Duplex Grades: SUS2205 (UNS S31803), SUS2507 (UNS S32750) — combining high tensile strength with outstanding resistance to chloride-induced stress corrosion cracking (Cl-SCC).

Key material properties include:

• Corrosion Resistance: High resistance to oxidation, pitting, and intergranular corrosion due to elevated chromium (Cr) and molybdenum (Mo) content.
• Mechanical Strength: Tensile strength ranging from 515 MPa (austenitic) to 795 MPa (duplex), with elongation exceeding 40% for austenitic grades.
• Thermal Stability: Maintains mechanical properties across operating temperatures from cryogenic levels (−196°C) to 870°C (austenitic) and up to 350°C (duplex, limited by sigma phase formation).
• Magnetic Properties: Non-magnetic or weakly magnetic in the annealed condition, suitable for applications requiring electromagnetic compatibility.

Specifications

Parameter	Specification	Standard Reference
Outer Diameter (OD)	6.0 mm – 108.0 mm (custom ranges available upon request)	ASTM A213 / ASME SA-213
Wall Thickness (WT)	0.5 mm – 6.0 mm (±0.1 mm tolerance)	ASTM A269 / ASME SA-269
Coil Length	15 m – 60 m (continuous coil, standard 25 m)	—
Coil Inner Diameter	500 mm – 1000 mm (configurable)	—
Surface Finish	2B (cold rolled and annealed), No. 4 (brushed), BA (bright annealed), EP (electropolished, Ra ≤ 0.5 μm)	ASTM A473
End Condition	Plain, beveled (37.5°), or per customer specification	ASME B1.20.1
Manufacturing Method	Seamless (hot/cold drawn) or welded (AOD/TIG)	ASTM A269 / EN 10216-5
Temperature Range	−196°C to +870°C (grade-dependent)	ASME BPVC Section VIII
Pressure Rating	Up to 20.0 MPa (design pressure, grade and dimension dependent)	ASME BPVC Section VIII Div. 1
Welding Suitability	Full-range weldable (TIG, MIG, laser); no preheat required for most grades	ASME BPVC Section IX
Packaging	Wooden crate or export-grade steel frame; moisture-proof inner wrapping	ISO 4180

Manufacturing Process

The production of Wenzhou Jixing coil tubes follows a tightly controlled, multi-stage manufacturing protocol to ensure consistency, dimensional accuracy, and metallurgical integrity:

1. Raw Material Sourcing: Virgin stainless steel billets and ingots are procured from certified mills with traceable chemical composition documentation. Incoming material undergoes spectroscopic verification (OES) to confirm compliance with specified grade chemistry.
2. Piercing & Hot Rolling: Billets are heated to 1150–1250°C and pierced to form hollow tubes, followed by hot rolling or hot extrusion to achieve approximate target dimensions.
3. Cold Drawing / Cold Expansion: Tubes are cold-drawn through precision-die tooling to achieve final OD and wall thickness within ±0.1 mm tolerance. Cold working enhances surface finish and dimensional repeatability.
4. Heat Treatment (Solution Annealing): Tubes are annealed at 1040–1120°C followed by controlled cooling (air or water quench, grade-dependent) to dissolve carbide precipitates, restore full solution hardenability, and eliminate residual stresses from cold working.
5. Pickling & Passivation: A controlled acid bath (nitric/hydrofluoric acid blend) removes oxide scale and forms a protective chromium oxide passivation layer, enhancing corrosion resistance.
6. Surface Finishing: Depending on application requirements, tubes receive additional finishing — mechanical polishing, electrolytic polishing (EP), or brush finishing — to achieve specified surface roughness values.
7. Coiling: Finished tubes are coiled onto precision-machined coil reels using automated coiling machines to prevent surface damage and maintain consistent coil geometry.
8. Non-Destructive Testing (NDT): 100% eddy current testing (ECT) is performed to detect wall thinning, surface cracks, and internal defects. Hydrostatic pressure testing is conducted at 1.5× design pressure with a minimum hold time of 10 seconds per joint.
9. Final Inspection & Packaging: Dimensional verification (OD, WT, straightness), surface inspection, and chemical/spectral analysis are documented. Tubes are protected with anti-corrosion wrapping and secured in export-grade packaging.

Applications

The versatility of Wenzhou Jixing stainless steel coil tubes enables deployment across a broad spectrum of industrial sectors:

• Food & Beverage Industry: Hygienic-grade piping for dairy processing, brewing, and pharmaceutical-grade fluid transfer. EP-finished 316L coil tubes meet FDA 21 CFR Part 117 and 3-A Sanitary Standards.
• Pharmaceutical & Biotech: Clean-in-place (CIP) and steam-in-place (SIP) compatible tubing for bioreactor loops, CIP manifolds, and sterile fluid distribution.
• Chemical & Petrochemical Processing: Reactor internals, heat exchanger tubing, and corrosion-resistant process piping handling aggressive media (acids, chlorides, oxidizing agents).
• Heat Exchangers & Boilers: Seamless coil tubes for shell-and-tube heat exchangers, condensers, evaporators, and boiler fire tubes, conforming to TEMA standards.
• Oil & Gas (Offshore & Onshore): Downhole tubing, wellhead assemblies, and subsea production piping in corrosive, high-pressure environments.
• Power Generation: Boiler tubes, superheater elements, and condensate lines in coal-fired, nuclear, and combined-cycle power plants.
• Medical Devices: Implant-grade tubing (316LVM) for orthopedic implants, surgical instruments, and dialysis equipment.
• Automotive & Aerospace: Exhaust system components, fuel lines, and hydraulic tubing requiring high-temperature and corrosion resistance.
• Marine & Offshore: Seawater piping, ballast systems, and desalination plant components (SUS2205/SUS2507 grades).
• Solar Thermal & Geothermal: Collector tubes and geothermal well casings operating in high-temperature, high-pressure conditions.

Quality Certifications & Compliance

Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality management system ensuring product conformity to international standards:

• ISO 9001:2015 — Quality Management Systems (QMS) certification covering design, manufacturing, and supply chain processes.
• ISO 14001:2015 — Environmental Management Systems, demonstrating commitment to sustainable manufacturing practices.
• ISO/IEC 17025 — Testing and calibration laboratory accreditation for in-house material testing facilities.
• EN 10204 3.1 — Third-party inspection and certification of material conformity with specified standards.
• ASME "S" Stamp — Authorization for manufacture of pressure-containing components per ASME Boiler and Pressure Vessel Code.
• PED 2014/68/EU — European Pressure Equipment Directive conformity for Category II–IV equipment.
• NACE MR0175 / ISO 15156 — Compliance for sour service (H₂S-containing) applications.
• NSF/ANSI 61 — Drinking water system component certification (for applicable grades and finishes).
• CE Marking — Conformity with European health, safety, and environmental protection standards.

Every batch of coil tube is accompanied by a Mill Test Certificate (MTC) documenting chemical composition, mechanical properties, heat treatment parameters, NDT results, and dimensional verification data. Full traceability from raw material lot to finished product is maintained through a barcode-based digital tracking system.

Unique Selling Points

• Continuous Coil Format: Eliminates field welding of short sections, reducing potential leak points and improving system integrity for hygienic and high-pressure applications.
• Precision Dimensional Control: ±0.1 mm wall thickness tolerance achieved through advanced cold-drawing technology, ensuring consistent heat transfer performance and pressure ratings.
• Customizable Surface Finishes: From standard 2B to ultra-smooth electropolished (Ra ≤ 0.25 μm) surfaces for pharmaceutical and semiconductor applications.
• Wide Grade Selection: From standard austenitic to super-austenitic and duplex grades, enabling optimal material selection for the most aggressive service environments.
• Full Traceability: Digital batch tracking from mill to end user with complete test documentation, ensuring compliance with regulatory requirements in pharmaceutical, food, and energy sectors.
• Engineering Support: Dedicated technical team providing material selection guidance, weld procedure qualification (WPQ/PQR), and finite element analysis (FEA) for critical applications.

Wenzhou Jixing Metal Materials Co., Ltd. — Engineering Excellence in Stainless Steel Tubular Solutions, Delivered in Continuous Coil Configuration for Maximum Process Efficiency.