Stainless Steel Coil Tube — Whole-Roll Flat Pricing (Coil Tube Product)
Product Overview
The Stainless Steel Coil Tube offered by Wenzhou Jixing Metal Materials Co., Ltd. is a precision-engineered tubular product supplied in continuous coil form. This product is categorized under the Commercial Procurement segment with a specific Pricing Model designation of Length-Based Pricing (specifically, By-Coil Pricing). The core commercial principle governing this product is whole-coil flat pricing — the entire coil is sold as a single, indivisible unit at a single lump-sum price, with no option for partial splitting or sectional cutting of the coil prior to delivery.
This pricing methodology is the most commonly employed approach for inventory clearance (spot stock liquidation) and tail-coil processing (end-roll disposal). It provides a straightforward, transparent, and cost-efficient procurement channel for buyers seeking to acquire stainless steel coil tube at competitive pricing while accepting the constraint of purchasing complete coil units.
Material & Properties
- Base Material: Austenitic stainless steel, typically conforming to grades such as SUS304 (UNS S30400), SUS316 (UNS S31600), or SUS304L (UNS S30403), depending on application requirements.
- Composition: Chromium (Cr) content ≥ 18%, Nickel (Ni) content ≥ 8% for 304 grade; elevated Molybdenum (Mo) content ≥ 2% for 316 grade, providing superior corrosion resistance.
- Surface Finish: Available in 2B (cold-rolled and annealed), BA (Bright Annealed), No. 4 (Brushed), or Mirror (8K) finishes to meet aesthetic and functional demands.
- Corrosion Resistance: Excellent resistance to atmospheric corrosion, chemical media, and aqueous environments; suitable for aggressive process conditions.
- Mechanical Properties: Tensile strength (T.S.) typically ≥ 520 MPa; elongation ≥ 40%; yield strength (Y.S.) ≥ 205 MPa (annealed condition).
- Temperature Resistance: Continuous service up to 870°C (1600°F); non-magnetic in annealed condition.
- Formability: High ductility permits cold bending, deep drawing, and spinning operations without cracking.
Specifications
| Parameter | Specification | Notes |
|---|---|---|
| Product Category | Coil Tube (盘管) | Continuous coil form, not cut to length |
| Pricing Model | Whole-Coil Flat Pricing (按卷定价) | Single lump-sum price per coil; no splitting |
| Procurement Classification | Commercial Procurement / Length-Based Pricing | Category: Business Procurement |
| Supply Condition | Spot Inventory / Tail-Coil Clearance | Common for stock liquidation |
| Coil Weight | Varies by diameter and wall thickness (typically 500–2,000 kg per coil) | Exact weight confirmed per coil |
| Outer Diameter (O.D.) | Customizable per client requirement | Standard ranges from 6 mm to 200 mm |
| Wall Thickness | Customizable per client requirement | Typical range: 0.5 mm – 6.0 mm |
| Tolerance (O.D.) | ± 5% or ± 0.05 mm (whichever is greater) | Per ASTM A554 / GB/T 14976 |
| Tolerance (Wall Thickness) | ± 10% | Per applicable standard |
| Coil ID (Inner Diameter of Coil) | 500 mm or 610 mm (standard) | Custom sizes available upon request |
| Packaging | Wooden pallet with protective wrapping; moisture-proof film | Export-grade packaging available |
Manufacturing Process
- Raw Material Selection: Virgin stainless steel slabs or hot-rolled coils are sourced from certified mills, undergoing incoming inspection for chemical composition (via Optical Emission Spectrometry — OES) and mechanical properties.
- Hot Rolling: Slabs are heated to temperatures between 1,100°C and 1,200°C and passed through rolling mills to achieve the desired preliminary dimensions.
- Pickling & Descaling: The hot-rolled coil is subjected to acid pickling (typically using a mixed acid solution of hydrofluoric acid (HF) and nitric acid (HNO₃)) to remove oxide scale and restore the passive chromium oxide layer.
- Cold Rolling / Cold Drawing: The pickled coil is cold-rolled or cold-drawn through precision dies and rollers to achieve final dimensions, improved surface finish, and enhanced mechanical properties (work hardening).
- Heat Treatment (Annealing): The cold-worked tube is annealed at temperatures between 1,000°C and 1,150°C in a protective atmosphere (hydrogen or vacuum) to relieve residual stresses, restore ductility, and refine the grain structure.
- Coiling & Winding: The finished tube is wound onto a coil core at controlled tension to maintain dimensional accuracy and prevent deformation. Each coil is weighed and tagged for traceability.
- Quality Inspection: Each coil undergoes dimensional verification (outer diameter, wall thickness, straightness), surface inspection, and hydrostatic or eddy-current testing to ensure integrity and conformity with applicable standards.
Applications
- Heat Exchangers & Boilers: Coil tubes are ideal for spiral-wound heat exchanger designs, condenser tubes, and boiler heating elements due to their continuous form and corrosion resistance.
- Petrochemical & Chemical Processing: Used in piping systems for transporting aggressive chemicals, acids, and caustic solutions in refineries and chemical plants.
- Food & Beverage Industry: Compliant with sanitary requirements for dairy, brewing, and food processing equipment where hygienic, corrosion-resistant tubing is essential.
- Pharmaceutical Manufacturing: Employed in cleanroom piping, fluid transfer lines, and equipment components requiring high purity and corrosion resistance.
- Automotive Industry: Used in exhaust systems, fuel lines, and turbocharger components where heat and corrosion resistance are critical.
- Architectural & Decorative Applications: Coil tubes are coiled into decorative elements for railings, handrails, and architectural facades.
- Spring & Coil Manufacturing: Raw material for industrial springs, wire coils, and elastic components.
- Heat Sink & Radiator Coils: Continuous coil form is directly used in radiator and heat sink manufacturing for HVAC and electronics cooling systems.
Quality Certifications & Standards
Wenzhou Jixing Metal Materials Co., Ltd. ensures that all stainless steel coil tube products conform to internationally recognized quality standards and undergo rigorous certification:
- ISO 9001:2015 — Quality Management System certification, ensuring consistent product quality and process control.
- ASTM A554 / ASTM A213 — Standard specifications for austenitic stainless steel welded and seamless tubing.
- GB/T 14976 — Chinese national standard for seamless stainless steel tubes for fluid transport.
- GB/T 12771 — Chinese national standard for welded stainless steel tubes for fluid transport.
- EN 10216-5 — European standard for welded stainless steel tubes for pressure purposes.
- JIS G 3458 — Japanese Industrial Standard for austenitic stainless steel tubes for pressure applications.
- Mill Test Certificate (MTC / EN 10204 3.1) — Each coil is accompanied by a mill test certificate documenting chemical composition, mechanical test results, and dimensional compliance.
- Third-Party Inspection: Products are available for inspection by internationally recognized bodies such as Bureau Veritas (BV), Lloyd's Register (LR), or SGS upon buyer request.
Unique Selling Points (USPs)
1. Transparent Whole-Coil Flat Pricing: The entire coil is sold at a single, all-inclusive price with no hidden charges for splitting, cutting, or partial delivery. This eliminates pricing ambiguity and reduces administrative overhead for the buyer.
2. Competitive Inventory Clearance Pricing: As a common method for spot stock liquidation and tail-coil processing, this pricing model offers significant cost advantages compared to made-to-order production, making it ideal for budget-conscious procurement.
3. Full Traceability: Each coil is individually tagged and traceable to its mill of origin, heat number, and production batch, ensuring complete supply chain transparency.
4. Flexibility in Application: The continuous coil form eliminates butt-weld joints inherent in cut-length tubing, resulting in superior pressure integrity, reduced leak risk, and enhanced fatigue resistance in coiled or spiral-wound applications.
5. Efficient Logistics: Coil form maximizes material density per shipping unit, reducing transportation costs and carbon footprint compared to equivalent lengths of cut tubing.
6. Established Supplier Credibility: Wenzhou Jixing Metal Materials Co., Ltd. operates within China's premier stainless steel manufacturing cluster in Wenzhou, Zhejiang Province, leveraging deep supply chain integration, competitive sourcing, and extensive industry experience.
Ordering & Procurement Notes
- Minimum Order Quantity (MOQ): One complete coil per order. Partial coil quantities are not available under the whole-coil flat pricing model.
- Lead Time: Spot inventory coils are available for immediate dispatch (typically 3–7 business days for logistics preparation). Custom coils require 25–40 business days for production.
- Payment Terms: Typically 100% irrevocable Letter of Credit (L/C) at sight or 100% advance Telegraphic Transfer (T/T). Terms are negotiable for long-term partners.
- Delivery Terms: Available under FOB (Free On Board), CIF (Cost, Insurance, and Freight), or EXW (Ex Works) Incoterms® 2020.
- Customization: While the pricing model is fixed per coil, buyers may specify coil weight, outer diameter, wall thickness, and surface finish requirements at the time of order to ensure suitability for their intended application.