Stainless Steel Coil Tube for Shell Gasifier Quench Port (Coiltube)

1. Product Overview

The Stainless Steel Coil Tube for Shell Gasifier Quench Port (hereinafter referred to as "Quench Port Coil Tube") is a specialized tubular component manufactured by Wenzhou Jixing Metal Materials Co., Ltd, engineered specifically for deployment in the quench port assembly of Shell Gas and Power (G&P) gasification systems. These coil tubes serve as critical heat exchanger elements within the quench vessel, where they are continuously exposed to extreme thermal cycling, high-velocity slurry flow, and chemically aggressive environments containing molten slag, syngas by-products, and aqueous cooling media.

The design and manufacturing of these coil tubes have been rigorously informed by extensive field failure analysis and engineering improvement studies — specifically the research documented in the technical study "Analysis and Improvement of Shell Gasifier Quench Port Coil Tube Damage." This study identified common failure modes including erosion-corrosion, thermal fatigue cracking, stress corrosion cracking (SCC), and mechanical deformation under cyclic loading, and directly informed the enhanced metallurgical specifications, geometric design parameters, and manufacturing protocols adopted in the current product generation.

2. Material & Properties

2.1 Base Material Selection

The coil tubes are fabricated from austenitic stainless steel grades selected for their superior resistance to thermal fatigue, chloride-induced stress corrosion cracking, and high-temperature oxidation. The primary material specification is as follows:

2.2 Mechanical Properties (Typical, Grade 316L)

2.3 Corrosion Resistance

3. Specifications

Parameter Specification Standard / Reference
Product Name Coil Tube (盘管) for Quench Port —
Product Code No. 563 Internal Catalog
Material Grade 316L / 321H / 347H / Alloy 625 (customizable) ASTM A269 / ASTM B407
Outer Diameter (OD) 19.05 mm – 101.6 mm (0.75" – 4") ASTM A269
Wall Thickness 1.5 mm – 6.35 mm (customizable per design) ASTM A269
Coil Diameter 600 mm – 3,000 mm (adjustable per installation) Project-specific
Coil Length (Total) 5 m – 150 m (per coil assembly) Project-specific
Surface Finish Pickled and passivated (Ra ≤ 1.6 μm) ASTM A967
Forming Method Induction bending / Hydraulic rotary bending —
Bend Radius (R) ≥ 3D (where D = OD of tube) ASTM B407
Maximum Service Temperature ≤ 870°C (continuous) ASME Section IX
Design Pressure Up to 2.5 MPa (gauge) ASME BPVC VIII
Welding Method Orbital TIG (GTAW) / Pulse TIG ASME Section IX
Heat Treatment Solution annealing at 1050–1150°C, followed by rapid water quench ASTM A269

4. Manufacturing Process

The manufacturing of Quench Port Coil Tubes follows a rigorous, multi-stage process designed to ensure metallurgical integrity, dimensional accuracy, and long-term service reliability:

  1. Raw Material Procurement and Inspection: Seamless stainless steel tubes are sourced from certified mills and subjected to 100% chemical composition analysis (via OES — Optical Emission Spectroscopy) and mechanical property verification. Each lot is accompanied by a Mill Test Certificate (MTC) conforming to EN 10204 Type 3.1.
  2. Dimensional Inspection and Cutting: Tubes are inspected for diameter, wall thickness, and straightness per ASTM A269 tolerances. Material is cut to required lengths using precision plasma or water-jet cutting to prevent thermal distortion and oxide inclusion.
  3. Surface Preparation: Tubes undergo acid pickling (per ASTM A967) to remove surface oxides and contaminants, followed by passivation treatment to establish a protective chromium oxide layer. Surface roughness is verified to Ra ≤ 1.6 μm.
  4. Coil Forming (Bending): Tubes are formed into the required coil geometry using induction heating bending or hydraulic rotary bending equipment. Induction bending is preferred as it provides localized, controlled heating that minimizes work hardening and maintains uniform microstructure. The minimum bend radius is maintained at ≥ 3D to prevent ovalization and wall thinning. Real-time monitoring of bend angle, radius, and tube ovality is performed during the forming process.
  5. Welding and Joining: All weld joints are executed using orbital TIG (GTAW — Gas Tungsten Arc Welding) with argon shielding on both internal and external surfaces. Weld parameters are optimized to minimize heat-affected zone (HAZ) width and distortion. Pulse TIG welding is employed for thin-walled sections to further reduce thermal input.
  6. Post-Weld Heat Treatment (PWHT): Welded assemblies undergo solution annealing at 1050–1150°C followed by rapid water quenching to restore full austenitic microstructure, eliminate residual stresses, and ensure uniform corrosion resistance throughout the component.
  7. Non-Destructive Testing (NDT):
    • 100% Visual Inspection (VT) of all welds and formed surfaces
    • 100% Radiographic Testing (RT) of critical weld joints per ASME BPVC Section V, Article 2
    • 100% Dye Penetrant Testing (PT) of weld surfaces per ASTM E709
    • Ultrasonic Testing (UT) of tube walls for internal defects per ASTM E213
    • Helium Leak Testing at 10⁻⁶ Pa·m³/s sensitivity for pressure boundary integrity
  8. Final Dimensional Verification and Coating: Completed coil tubes are measured for overall dimensions, coil diameter, pitch, and straightness. A protective coating (if specified) is applied to prevent transport damage.
  9. Documentation and Traceability: Each coil tube assembly is assigned a unique serial number with full traceability to raw material lot, manufacturing parameters, NDT results, and final inspection data.

5. Applications

The Stainless Steel Coil Tube for Shell Gasifier Quench Port is deployed in the following industrial applications:

6. Quality Certifications

Wenzhou Jixing Metal Materials Co., Ltd maintains comprehensive quality management and product certification systems ensuring conformance to international standards:

7. Unique Selling Points

The Quench Port Coil Tubes offered by Wenzhou Jixing Metal Materials Co., Ltd distinguish themselves through the following value propositions:

8. Technical Study Reference

Reference Document: "Analysis and Improvement of Shell Gasifier Quench Port Coil Tube Damage" (《壳牌气化炉激冷口盘管损坏原因分析及改进》)

This technical study, catalogued as Product Knowledge Point No. 563 under the "Documentary Learning" (文献学习) category, provides the foundational engineering rationale for the current product design. The study systematically analyzed failure modes including:

  • Erosion-corrosion at high-velocity slurry impact zones
  • Thermal fatigue cracking due to cyclic temperature differentials between slag-side and cooling-water-side surfaces
  • Chloride-induced stress corrosion cracking (Cl-SCC) in the quench water environment
  • Mechanical deformation and distortion under combined thermal and hydraulic loading
  • Weld joint degradation due to inadequate heat input control and insufficient post-weld treatment

The improvements implemented based on this study include enhanced material grades with higher Cr/Mo content, optimized coil geometry to reduce flow-induced vibration, increased wall thickness at high-erosion zones, improved welding procedures with reduced HAZ, and enhanced surface passivation treatments.

9. Ordering and Customization

Wenzhou Jixing Metal Materials Co., Ltd offers both standard and custom-manufactured Quench Port Coil Tubes. Customers are encouraged to provide detailed engineering drawings, material specifications, service conditions (temperature, pressure, medium composition), and applicable standards for tailored product development. Technical consultation and sample fabrication are available upon request.

Manufacturer: Wenzhou Jixing Metal Materials Co., Ltd (温州继兴金属材料有限公司)

Product Code: 563

Classification: Documentary Learning / Technical Reference