Stainless Steel Steam Coil Tube for Industrial Blending Tanks
Product Overview
The Stainless Steel Steam Coil Tube (Coil Tube) manufactured by Wenzhou Jixing Metal Materials Co., Ltd. is a precision-engineered heat exchange component designed for thermal management applications within industrial blending tanks and process vessels. This product, catalogued as Item No. 825, is specifically engineered to withstand the demanding conditions of steam-heated mixing and blending operations, where consistent thermal transfer and structural integrity are critical to process safety and efficiency.
Steam coil tubes serve as the core heat transfer element in blending tanks (调和槽), delivering thermal energy to bulk liquids through conduction and convection. The product is designed to address industry-wide challenges of coil tube leakage, thermal fatigue, and corrosion degradation—issues documented extensively in process engineering literature and field service analyses.
Material & Properties
The coil tube is fabricated from high-grade austenitic stainless steel, selected for superior corrosion resistance, mechanical strength, and thermal conductivity under continuous steam exposure conditions.
- Primary Alloy Grades: AISI 304 (UNS S30400), AISI 316L (UNS S31603), and AISI 321 (UNS S32100)
- Corrosion Resistance: Excellent resistance to pitting (Pitting Corrosion), crevice corrosion (Crevice Corrosion), and intergranular corrosion (Intergranular Corrosion) in acidic and alkaline process environments
- Chromium Content: ≥18% (minimum), providing robust passive film formation
- Molybdenum Content: 2.0–3.0% (in 316L grade), enhancing chloride ion (Cl⁻) resistance
- Maximum Service Temperature: Up to 870°C (1600°F) for 304/316L grades; up to 1150°C (2100°F) for 321 grade
- Thermal Conductivity: 16.3 W/(m·K) at 100°C (typical for austenitic grades)
- Surface Finish: Electropolished (Ra ≤ 0.4 μm) or mechanical polish (Ra ≤ 0.8 μm) available
Technical Specifications
| Parameter | Specification |
|---|---|
| Product Name | Stainless Steel Steam Coil Tube (盘管 / Coil Tube) |
| Catalogue Reference | No. 825 |
| Outer Diameter (OD) | Φ12 mm – Φ50 mm (customizable) |
| Wall Thickness | 0.8 mm – 3.0 mm |
| Coil Pitch / Spacing | 20 mm – 80 mm (configurable per thermal load) |
| Coil Diameter | Φ150 mm – Φ1500 mm (spiral coil) |
| Tube Length per Coil | 5 m – 60 m (continuous) |
| Operating Pressure (Steam Side) | 0.1 MPa – 1.6 MPa (gauge) |
| Operating Temperature Range | −40°C to +350°C |
| Steam Pressure Class | PN16 / PN25 / PN40 |
| End Connection Types | Flanged (ANSI/ASME B16.5), Threaded (NPT/BSP), Welded (Socket Weld) |
| Coating / Surface Treatment | Passivated, Pickled & Passivated (P&P), Electropolished |
| Welding Standard | AWS D16.1 (Stainless Steel Welding) |
| Applicable Standards | ASTM A213 / A269, GB/T 12771, EN 10216-5, JIS G3459 |
| Manufacturing Origin | Wenzhou, Zhejiang Province, P.R. China |
Manufacturing Process
The production of high-integrity stainless steel coil tubes follows a rigorous multi-stage manufacturing protocol designed to eliminate the failure modes identified in field analyses of steam coil tube leakage in blending tanks.
- Raw Material Inspection: Incoming stainless steel seamless tube stock undergoes 100% chemical composition analysis (via XRF and wet chemistry) and mechanical property verification (tensile strength, elongation) in accordance with ASTM A213/A269 specifications.
- Hydrostatic Testing: Each tube length is subjected to full-length hydrostatic pressure testing at 1.5× the maximum operating pressure to verify wall integrity prior to forming.
- Cold Coiling / Spiral Winding: Tubes are formed into precise spiral coils using CNC-controlled coiling equipment, ensuring uniform coil pitch and minimizing work-hardening (Cold Work Hardening) that could compromise fatigue life.
- Welding of Coil Ends & Manifold Connections: All welds are performed using Gas Tungsten Arc Welding (GTAW / TIG) with argon gas backing to prevent internal oxidation. Weld beads are ground flush and inspected for full penetration.
- Pickling and Passivation: Post-weld heat-affected zones (HAZ) are treated via acid pickling (nitric-hydrofluoric acid blend) followed by passivation to restore the chromium oxide passive layer across all exposed surfaces.
- Non-Destructive Testing (NDT): Radiographic Testing (RT) per ASME Section V, Article 2 and Dye Penetrant Testing (PT) per ASTM E1659 are performed on all critical welds and coil joints.
- Final Assembly & Pressure Testing: The completed coil assembly is pressure-tested at 1.5× design pressure for a minimum hold time of 30 minutes, with zero acceptable leakage.
Applications
The Stainless Steel Steam Coil Tube is deployed across a broad spectrum of industrial thermal processing applications:
- Petrochemical Blending Tanks: Steam heating of crude oil fractions, refined petroleum products, and chemical intermediates in storage and blending vessels (调和槽)
- Pharmaceutical Processing: GMP-compliant heating of aqueous solutions, sterilization systems, and CIP (Clean-In-Place) systems
- Food & Beverage Industry: Pasteurization, pasteurization tank heating, and thermal processing of dairy, juice, and sauce products
- Chemical Processing: Reactor jacket heating, distillation column reboilers, and thermal oil exchange systems
- Textile & Dyeing: Dye bath temperature control and continuous thermal processing lines
- Power Generation: Auxiliary steam coil systems in boiler feedwater heating and condensate recovery
- Marine & Offshore: Corrosion-resistant heat exchange in seawater-cooled systems and offshore platform utilities
Quality Certifications & Compliance
Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality assurance framework ensuring full traceability and regulatory compliance:
- ISO 9001:2015 — Quality Management System (QMS) certified
- ISO 14001:2015 — Environmental Management System (EMS) certified
- ISO 45001:2018 — Occupational Health & Safety Management System certified
- ASME "S" Stamp — Authorized National Board (NBA) Manufacturer for pressure vessels and heat exchangers
- CE Marking — Compliance with EU Pressure Equipment Directive (PED 2014/68/EU) and Machinery Directive
- PED Category II/III — Authorized for construction of steam coils operating above 0.5 bar(g) and 100°C
- Material Traceability: Full heat-number traceability (Heat Number Traceability) from mill certificate (Mill Test Certificate / MTC) through final product documentation
- Third-Party Inspection: Available upon request via SGS, TÜV, Bureau Veritas, or DNV for critical applications
Unique Selling Points & Engineering Advantages
This product line addresses the specific failure mechanisms identified in the technical literature regarding "Leakage Analysis and Remediation of Steam Coil Tubes in Blending Tanks" (《调和槽中蒸汽盘管的渗漏分析及治理》). The engineering advantages include:
- Leak-Resistant Design: Enhanced wall thickness at stress-concentration zones (weld joints, tube bends, and tank penetration points) to mitigate the primary failure modes of thermal fatigue cracking and corrosion-induced wall thinning
- Thermal Cycling Durability: Optimized coil geometry and material selection to withstand repeated thermal cycling (Thermal Cycling) without progressive fatigue damage
- Corrosion Mitigation: 316L grade with molybdenum enrichment provides superior resistance to chloride stress corrosion cracking (Chloride Stress Corrosion Cracking / Cl-SCC), a leading cause of coil tube failure in marine and chemical environments
- Custom Engineering: Full customization of coil diameter, pitch, tube count, and connection configuration to match specific vessel geometry and thermal duty requirements
- Extended Service Life: Electropolished surface finish reduces biofilm attachment and corrosion initiation sites, extending operational life by 40–60% compared to standard mill-finish alternatives
- Field-Validated Performance: Product designs informed by real-world failure analysis data from industrial blending tank operations, incorporating lessons learned from documented leakage incidents
Note: All dimensions, pressure ratings, and material specifications are customizable to meet project-specific requirements. Wenzhou Jixing Metal Materials Co., Ltd. provides full engineering support, including thermal load calculations, Finite Element Analysis (FEA) for stress verification, and detailed Installation & Maintenance (I&M) documentation for each delivered coil tube assembly.