Stainless Steel Coil Tube – Theoretical Weight Settlement with Agreed Tolerance (Wenzhou Jixing Metal Materials)
Product Overview
Wenzhou Jixing Metal Materials Co., Ltd. offers high-grade stainless steel coil tubes engineered for demanding industrial applications. These coil tubes are supplied in continuous spiral form, providing maximum material utilization, reduced waste, and superior processing efficiency for downstream manufacturers. The product line encompasses a broad range of stainless steel grades, dimensions, and wall thicknesses, all manufactured to meet international quality standards and industry specifications.
A defining commercial feature of this product offering is the Theoretical Weight Settlement with Agreed Tolerance model. Under this framework, coil tubes are settled based on calculated theoretical weight (derived from nominal dimensions and material density), with a mutually agreed permissible deviation range. Should the actual weighed weight exceed the agreed tolerance, settlement is adjusted to reflect the true measured weight. This approach balances operational efficiency with commercial fairness, ensuring both supplier and buyer are protected from disproportionate cost variances.
Material & Properties
Wenzhou Jixing Metal Materials coil tubes are available in a comprehensive selection of austenitic, ferritic, duplex, and precipitation-hardening stainless steel grades. Key material properties include:
- Corrosion Resistance: Superior resistance to oxidation, pitting, and crevice corrosion in aggressive chemical and marine environments, owing to high chromium (≥10.5%) and nickel content.
- Mechanical Strength: Excellent tensile and yield strength at both ambient and elevated temperatures, with minimal loss of structural integrity.
- Weldability: Austenitic grades offer outstanding welding characteristics with no pre-heat or post-heat treatment required in most configurations.
- Temperature Performance: Maintains mechanical properties from cryogenic temperatures (down to −196°C) up to 800–1150°C depending on grade.
- Magnetic Properties: Austenitic grades are essentially non-magnetic in the annealed condition; ferritic and martensitic grades are magnetic.
Specifications
| Parameter | Specification / Range |
|---|---|
| Product Type | Stainless Steel Coil Tube (Continuous Spiral Form) |
| Material Grades | 304, 304L, 316, 316L, 321, 310S, 317L, 2205, 2507, 430, 17-4PH |
| Outer Diameter (OD) | 6 mm – 325 mm (custom sizes available) |
| Wall Thickness | 0.5 mm – 12 mm (custom thickness available) |
| Coil Inner Diameter | Standard: 200 mm – 600 mm; Customizable upon request |
| Coil Length | 1,000 m – 10,000 m per coil (negotiable) |
| Surface Finish | 2B, BA (Bright Annealed), No. 1, Polished, Matte |
| Manufacturing Process | Seamless or Welded (ERW / Autogenous Welded & Cold-Finished) |
| Applicable Standards | ASTM A213, ASTM A269, ASTM A312, EN 10216-5, GB/T 12771, JIS G3459 |
| Settlement Method | Theoretical Weight with Agreed Tolerance; Excess Deviation Settled at Actual Weight |
| Customization | Custom dimensions, special grades, special surface treatments, and packaging available |
Manufacturing Process
Wenzhou Jixing Metal Materials employs a rigorous, multi-stage manufacturing process to ensure consistent quality and dimensional accuracy:
- Raw Material Selection: Only certified stainless steel billets or strip from accredited mills are procured, with full chemical composition and mechanical property verification prior to processing.
- Hot Rolling / Extrusion: For seamless tubes, billets are heated to forging temperature and pierced or extruded to produce the initial tube blank. For welded tubes, precision cold-rolled strip is used.
- Forming & Welding: Strip is precisely formed into the desired circular cross-section. Welded tubes undergo autogenous TIG welding or ERW (Electric Resistance Welding) with real-time seam inspection.
- Cold Drawing / Cold Rolling: Tubes are cold-worked to achieve exact final dimensions, superior surface finish, and enhanced mechanical properties. Multiple passes may be applied for tight tolerance requirements.
- Heat Treatment / Annealing: Solution annealing in a controlled atmosphere eliminates residual stresses, restores ductility, and ensures full corrosion resistance. Bright annealing (BA) produces a mirror-like surface without pickling.
- Coiling: Finished tubes are wound into continuous coils using precision coiling equipment to maintain dimensional consistency and prevent surface damage.
- Final Inspection: Every coil undergoes comprehensive testing including hydrostatic pressure testing, dimensional measurement, surface inspection, and chemical/spectrometric analysis.
Applications
Wenzhou Jixing Metal Materials coil tubes serve a wide spectrum of industrial sectors:
- Heat Exchangers & Boilers: Spiral coil tubes are ideal for manufacturing shell-and-tube heat exchangers, condensers, evaporators, and boiler components where high thermal efficiency and corrosion resistance are critical.
- Chemical & Petrochemical Processing: Used in piping, reactors, distillation columns, and heat exchangers handling aggressive chemicals, acids, and hydrocarbons.
- Food & Pharmaceutical Industry: Hygienic-grade coil tubes (BA finish) for processing equipment, CIP/SIP systems, and sanitary piping where purity and cleanability are paramount.
- Energy & Power Generation: Components for nuclear, solar thermal, and conventional power plant systems requiring reliable performance under extreme conditions.
- Automotive & Aerospace: Exhaust systems, fuel lines, hydraulic components, and structural elements demanding high strength-to-weight ratios.
- Marine & Offshore: Seawater cooling systems, desalination plants, and offshore platform piping where chloride-induced corrosion is a concern.
- Medical Devices: Surgical instruments, implant components, and diagnostic equipment requiring biocompatible, corrosion-free materials.
- Construction & Architecture: Structural elements, railings, facades, and decorative applications where aesthetics and durability are required.
Quality Certifications & Compliance
Wenzhou Jixing Metal Materials Co., Ltd. maintains a robust quality assurance framework to guarantee product excellence:
- ISO 9001:2015 – Quality Management System certified
- ISO 14001 – Environmental Management System certified
- ISO/TS 22163 – Automotive quality management (where applicable)
- EN 10204 3.1 / 3.2 – Material test certificates per European standard
- Mill Test Certificates (MTC) – Provided with every shipment, covering chemical composition, mechanical properties, and heat treatment records
- Third-Party Inspection – Available upon request from organizations such as SGS, Bureau Veritas, or TÜV
- Compliance with ASTM, EN, GB, JIS, and ASME standards as specified by the customer
Commercial Settlement Model: Theoretical Weight with Agreed Tolerance
The settlement methodology for Wenzhou Jixing Metal Materials coil tubes follows the Theoretical Weight + Agreed Tolerance framework, which provides a balanced and efficient commercial arrangement:
- Theoretical Weight Calculation: Settlement is based on the calculated weight derived from nominal OD, wall thickness, length, and the material density of the specific steel grade. This eliminates the need for weighing every coil, streamlining logistics and reducing administrative overhead.
- Agreed Tolerance Range: A mutually defined permissible deviation (commonly ±1% to ±3%, depending on product specifications and order volume) is established between buyer and seller prior to shipment. Within this range, the theoretical weight is accepted as the settlement basis.
- Excess Deviation Adjustment: If the actual weighed weight deviates beyond the agreed tolerance, the settlement is adjusted to reflect the true measured weight. This ensures fairness and prevents either party from bearing disproportionate cost risk.
- Efficiency & Fairness: This model combines the speed and simplicity of theoretical weight settlement with the protection of actual-weight verification, making it particularly suitable for high-volume coil tube orders where logistical efficiency is critical.
Why Choose Wenzhou Jixing Metal Materials?
- Extensive Grade & Size Range: One of the most comprehensive stainless steel coil tube offerings in the industry, covering all major austenitic, ferritic, duplex, and PH grades.
- Customization Capability: Fully capable of producing to customer-specific dimensions, surface finishes, and packaging requirements.
- Proven Manufacturing Expertise: State-of-the-art cold-rolling, drawing, welding, and annealing facilities ensuring consistent quality at scale.
- Transparent Commercial Terms: The theoretical weight settlement with agreed tolerance model offers clarity, efficiency, and fairness for both parties.
- Global Supply Capability: Experienced in international trade with robust export packaging, documentation, and logistics support.
- Full Traceability: Every coil is traceable to its mill heat number with complete test documentation provided.
For detailed quotations, sample requests, or custom specifications, contact Wenzhou Jixing Metal Materials Co., Ltd. directly to discuss your project requirements and receive tailored technical and commercial support.