Stainless Steel Coil Tube (Coiltube) for Edge Oil Well Collection Pipelines
Product Overview
The Stainless Steel Coil Tube (Coiltube), manufactured by Wenzhou Jixing Metal Materials Co., Ltd., is a precision-engineered continuous-length tubular product designed for demanding industrial applications, particularly in the oil and gas sector. This coil tube is specifically optimized for use in edge oil well collection pipelines (边缘油井集油管线), where it serves as an integral component of coil heating systems (盘管加热系统) to maintain fluid transportability in remote and harsh operating environments.
Unlike conventional straight-length tubes, coil tubes are supplied in continuous helical coils, eliminating the need for field welding and joints, thereby significantly reducing leak points, installation time, and long-term maintenance costs. This product represents a convergence of metallurgical excellence and process engineering tailored for the unique challenges of peripheral oilfield infrastructure.
Material & Properties
The coil tube is fabricated from high-grade austenitic stainless steels, ensuring superior corrosion resistance, mechanical integrity, and thermal stability across a wide operating temperature range.
- Primary Material Grades: 304 (UNS S30400), 304L (UNS S30403), 316 (UNS S31600), 316L (UNS S31603), 321 (UNS S32100), 347H (UNS S34700)
- Corrosion Resistance: Excellent resistance to pitting (点蚀), crevice corrosion (缝隙腐蚀), and intergranular corrosion (晶间腐蚀) in chloride-containing environments typical of oil and gas production fluids
- Temperature Range: Suitable for continuous service from cryogenic temperatures (−196°C / −320°F) up to 870°C (1,598°F) depending on grade selection
- Mechanical Properties: High tensile strength (抗拉强度), adequate elongation (延伸率), and fatigue resistance (疲劳抗性) for cyclic thermal loading conditions
- Surface Finish: Available in mill finish (工业表面), electropolished (电解抛光), pickled and passivated (酸洗钝化), or custom surface treatments
Specifications
| Parameter | Specification / Range |
|---|---|
| Outer Diameter (外径, OD) | 6.35 mm – 323.85 mm (¼" – 12¾") |
| Wall Thickness (壁厚, WT) | 0.5 mm – 20.0 mm (0.020" – 0.787") |
| Coil Diameter (盘管直径, CD) | 1,000 mm – 3,000 mm (customizable) |
| Coil Length (盘管长度) | Up to 5,000 m (16,400 ft) continuous |
| Standard Compliance (执行标准) | ASTM A213, ASTM A269, ASME SA-213, ASME SA-269, GB/T 12771, GB/T 13296 |
| Manufacturing Method (制造工艺) | Seamless (无缝) / Welded (焊制: ERW, TIG, Laser) |
| End Condition (端部状态) | Plain, Beveled (坡口), Threaded (螺纹), or Custom |
| Heat Treatment (热处理) | Solution Annealed (固溶退火), Stress Relieved (去应力) |
| Maximum Operating Pressure (最大工作压力) | Up to 350 bar (5,075 psi), grade-dependent |
| Coating / Protection (防护) | Passivation (钝化), PTFE-lined (特氟龙涂层), or None |
Manufacturing Process
The production of Wenzhou Jixing's stainless steel coil tube follows a rigorous multi-stage manufacturing protocol to ensure dimensional accuracy, metallurgical homogeneity, and consistent mechanical performance:
- Raw Material Selection & Inspection (原材料筛选与检验): Only certified ingots or hot-rolled strip from accredited mills are accepted, with full chemical composition verification (光谱分析) and mechanical property testing.
- Forming & Welding (成型与焊接): For welded coil tubes, precision roll-forming (精密辊压成型) is followed by high-frequency resistance welding (ERW) or continuous TIG welding to achieve uniform weld integrity. Seamless tubes are produced via hot or cold piercing (热轧穿孔/冷轧穿孔) processes.
- Heat Treatment (热处理): Solution annealing (固溶处理) at temperatures between 1,010°C and 1,150°C, followed by rapid water quenching to achieve a fully austenitic microstructure with maximum corrosion resistance.
- Pickling & Passivation (酸洗钝化): Removal of oxide scale and formation of a protective chromium oxide layer (Cr₂O₃) to enhance surface corrosion resistance.
- Coiling & Spooling (盘卷): The continuous tube is wound into helical coils of specified diameter using precision spooling equipment to maintain dimensional tolerances and prevent deformation.
- Non-Destructive Testing (无损检测): 100% inspection via eddy current (涡流检测), ultrasonic testing (超声波检测), and visual examination (目视检测) to detect internal and surface defects.
- Final Dimensional & Pressure Testing (尺寸与压力测试): Hydrostatic pressure testing (水压试验) at 2× working pressure, with dimensional verification against applicable standards.
Applications
The Stainless Steel Coil Tube is engineered for a broad spectrum of industrial applications, with particular emphasis on:
- Edge Oil Well Collection Pipelines (边缘油井集油管线): Primary application — used as coil heating elements (盘管加热元件) to maintain crude oil flow temperature in remote peripheral wells where pipeline insulation alone is insufficient. The continuous coil configuration provides uniform heat distribution and eliminates field joints in difficult-to-access locations.
- Oil & Gas Production Systems: Flow lines, gas-lift systems, separator internals, and subsea umbilicals where corrosion resistance and leak-free integrity are critical.
- Chemical Processing (化工): Heat exchangers (换热器), reactor internals, and process piping handling aggressive media.
- Food & Pharmaceutical Industry (食品与制药): Sanitary-grade coil tubes for hygienic fluid transport and heat exchange systems.
- Power Generation (发电): Boiler tubes, superheater coils, and condensate recovery systems in power plants.
- Automotive & HVAC: Radiator tubes, air conditioning coil tubes, and heat recovery systems.
Quality Certifications & Standards Compliance
Wenzhou Jixing Metal Materials Co., Ltd. maintains comprehensive quality assurance systems and holds the following certifications:
- ISO 9001:2015 — Quality Management System (质量管理体系)
- ISO 14001:2015 — Environmental Management System (环境管理体系)
- ISO 45001:2018 — Occupational Health & Safety Management System (职业健康安全管理体系)
- NACE MR0175 / ISO 15156 — Compliance for sour service environments (含硫环境适用性)
- API 5L / API 5CT — Certification for petroleum and natural gas industry applications
- CE Marking — European Conformity for pressure equipment (PED 2014/68/EU)
- Third-Party Inspection (第三方检验): Available upon request — SGS, BV, DNV, Lloyd's Register, or TÜV
Unique Selling Points
The Wenzhou Jixing Stainless Steel Coil Tube distinguishes itself through the following competitive advantages:
- Continuous Length Without Field Welds: Eliminates up to 90% of potential leak points compared to straight tube assemblies, dramatically improving system reliability in remote edge oil well applications.
- Application-Specific Engineering for Coil Heating Systems: Optimized coil diameter, pitch, and wall thickness ratios specifically designed for efficient thermal transfer in oil well collection pipeline heating scenarios.
- Full Traceability (全程可追溯): Each coil carries a unique heat number and production batch identifier, enabling complete material traceability from raw ingot to finished product.
- Custom Fabrication Capability: Tailored coil configurations, special grades, and custom dimensions available to meet project-specific requirements.
- Rapid Deployment: Pre-coiled and pre-tested configurations enable faster on-site installation, reducing project timelines and associated costs in remote locations.