Stainless Steel Coil Tube (Coiltube) — Industrial Pumping & Fluid Transfer Grade

Wenzhou Jixing Metal Materials Co., Ltd. (温州继兴金属材料有限公司) presents its premium-grade Stainless Steel Coil Tube (Coiltube), a precision-engineered continuous-length tubing product designed for demanding industrial fluid transport, high-pressure pumping, and structural applications. This product is manufactured to international standards and is widely recognized for its superior mechanical integrity, corrosion resistance, and adaptability across diverse engineering environments.

Product Overview

The Stainless Steel Coil Tube (盘管 / Coil Tube) is a continuous, spring-coiled seamless or welded stainless steel tubing supplied in large-diameter coils for easy handling, storage, and on-site deployment. Unlike straight-length pipe stock, coil tube is wound in concentric loops during the manufacturing process, enabling extended lengths without the need for joints or couplings — a critical advantage in applications requiring uninterrupted fluid pathways over long distances.

This product line encompasses a wide range of outer diameters (OD) and wall thicknesses, tailored to meet the specific requirements of hygienic processing, chemical handling, HVAC systems, structural engineering, and high-performance pumping operations. The coil configuration eliminates joint-related failure points, reduces installation time, and minimizes the risk of leakage at connection interfaces.

Unique Selling Points

Material & Properties

The Coil Tube is manufactured from premium austenitic stainless steel grades, selected for their optimal combination of mechanical strength, ductility, and corrosion resistance. The primary grades offered include:

Available Stainless Steel Grades

Mechanical Properties (Typical — SUS 304 Grade)

Chemical Composition (Typical — SUS 304)

Specifications

Typical Dimensional Specifications for Stainless Steel Coil Tube
Parameter Specification / Range Standard Reference
Outer Diameter (OD) Φ6.0 mm – Φ114.3 mm (1/4" – 4") ASTM A269 / ASTM A213
Wall Thickness 0.5 mm – 6.0 mm (0.020" – 0.236") ASTM A269 / EN 10216-5
Coil Outer Diameter (Winding Diameter) Φ300 mm – Φ1,200 mm (adjustable per order) Manufacturer Standard
Coil Length (Continuous Strand Length) 50 m – 500 m per coil (configurable) Manufacturer Standard
Surface Finish Mirror Polish (Ra ≤ 0.25 μm), Electropolished, Brushed, Pickled & Passivated, Commercial (2B) ASTM A269 / ISO 11463
End Condition Open ends, Beveled, Threaded (BSP/NPT), Flanged, Custom ASME B1.20.1 / B1.20.2
Manufacturing Method Seamless (Hot/Cold Drawn) or Longitudinally Welded (Laser/ERW) ASTM A269 / ASTM A554
Operating Temperature Range −196°C (cryogenic) to +870°C (SUS 321 grade) ASME BPVC Section VIII
Maximum Working Pressure Up to 35 MPa (5,075 psi) — dependent on OD and wall thickness ASME B31.3 / EN 13480
Tolerance on OD ±0.05 mm to ±0.15 mm (per OD range) ASTM A269 / EN 10217
Tolerance on Wall Thickness ±10% of nominal (minimum ±0.05 mm) ASTM A269 / EN 10217
Heat Treatment Condition Annealed (Solution Annealed), Stress-Relieved ASTM A269
Coating / Passivation Passivated (Nitric Acid or Citric Acid), Optional Epoxy/Polyurethane Internal Coating ASTM A967 / EN 10088

Manufacturing Process

The production of high-quality Stainless Steel Coil Tube involves a meticulously controlled multi-stage manufacturing process, ensuring dimensional accuracy, metallurgical integrity, and surface quality throughout the entire product lifecycle.

Process Flow

  1. Raw Material Selection & Incoming Inspection: High-purity stainless steel billets or slabs are sourced from certified mill producers. Each batch undergoes spectroscopic analysis (Optical Emission Spectroscopy, OES) to verify chemical composition compliance with the specified grade requirements.
  2. Hot Rolling & Piercing: The steel billet is heated to approximately 1,100°C – 1,250°C and hot-rolled to reduce cross-section. The solid round is then pierced on a mandrel mill to produce a seamless tube blank with the desired OD and approximate wall thickness.
  3. Hot Extrusion (Alternative Route): For certain dimensions, hot extrusion through a die and mandrel assembly is employed to produce seamless tube blanks with tighter dimensional tolerances.
  4. Annealing & Pickling: The hot-rolled tube is furnace-annealed at 1,050°C – 1,150°C followed by controlled air or water cooling. The oxide scale (mill scale) is then removed via acid pickling (typically a mixture of hydrofluoric and nitric acid), restoring the metallic surface and initiating passivation.
  5. Cold Drawing & Sizing: The annealed tube is cold-drawn through precision dies and mandrels to achieve exact final OD and wall thickness dimensions. This process enhances mechanical strength (work hardening) and improves surface finish quality.
  6. Intermediate Annealing (if required): For multi-stage cold working, intermediate annealing cycles are performed to restore ductility and prevent cracking during subsequent drawing operations.
  7. Surface Finishing: Depending on the application requirement, the tube may undergo mechanical polishing (internal and external), electropolishing (electrochemical polishing), or chemical passivation to achieve the specified surface roughness (Ra value) and corrosion resistance.
  8. Coiling (Spring Winding): The finished tube is wound onto a large-diameter coil former using a controlled winding mechanism. The winding tension, coil pitch, and layer stacking are precisely managed to ensure uniform stress distribution and prevent deformation or kinking of the tube.
  9. Final Heat Treatment (Stress Relief): The coiled tube may undergo a low-temperature stress-relief anneal (typically 600°C – 800°C for austenitic grades) to relieve residual stresses introduced during coiling, ensuring dimensional stability.
  10. Quality Inspection & Testing: Each coil undergoes comprehensive non-destructive testing (NDT) and dimensional verification as detailed in the Quality Certifications section below.
  11. Packaging & Dispatch: Inspected coils are wrapped in protective film or paper, secured on wooden or steel pallets, and prepared for shipping with appropriate documentation.

Applications

The Stainless Steel Coil Tube is a versatile product employed across a broad spectrum of industrial and engineering applications. Key application domains include:

1. Construction & Concrete Pumping

One of the most notable applications is in long-distance concrete pumping systems. Research has demonstrated the capability of stainless steel coil tube configurations to pump C70 self-compacting concrete (SCC) over horizontal distances exceeding 1,590 meters. The joint-free continuous nature of coil tube minimizes pressure loss and reduces the risk of blockage or leakage at couplings, making it ideal for large-scale infrastructure projects including bridge construction, dam building, and high-rise building construction.

2. Food & Beverage Processing

In the food and beverage industry, the Coil Tube is extensively used for hygienic fluid transfer systems in dairy processing, brewery operations, beverage production lines, and pharmaceutical manufacturing. The mirror-polished or electropolished interior surfaces prevent bacterial adhesion and facilitate easy cleaning (Clean-in-Place, CIP), meeting stringent regulatory requirements.

3. Chemical & Petrochemical Processing

The superior corrosion resistance of SUS 316 and SUS 316L grades makes the Coil Tube an ideal choice for chemical processing plants, petrochemical refineries, and acid/alkali handling systems. The tube is used for transporting aggressive chemical media, corrosive solvents, and high-purity process fluids.

4. HVAC & Refrigeration Systems

In heating, ventilation, air conditioning (HVAC), and refrigeration applications, the Coil Tube is used for refrigerant distribution lines, condenser tubes, and heat exchanger assemblies. The stainless steel construction provides long-term durability in environments exposed to moisture, condensation, and temperature cycling.

5. Medical & Pharmaceutical Equipment

The high-purity stainless steel Coil Tube is employed in medical gas delivery systems, hospital plumbing infrastructure, pharmaceutical manufacturing lines, and laboratory instrumentation. The biocompatibility and corrosion resistance of the material ensure patient safety and product purity.

6. Marine & Offshore Engineering

In marine and offshore environments, SUS 316L Coil Tube is used for seawater intake systems, ballast water treatment, desalination plants, and subsea fluid transfer lines. The molybdenum-enhanced corrosion resistance provides protection against pitting and crevice corrosion in chloride-rich seawater.

7. Automotive & Aerospace

In the automotive industry, the Coil Tube is used for exhaust systems, fuel delivery lines, and brake fluid conduits. In aerospace applications, it is employed in hydraulic systems, fuel lines, and pneumatic actuator tubing where weight, corrosion resistance, and reliability are critical.

8. Solar Thermal & Energy Systems

The Coil Tube is utilized in solar thermal collector systems, geothermal heat exchange loops, and concentrated solar power (CSP) plants. Its thermal stability and resistance to thermal fatigue make it suitable for repeated heating and cooling cycles.

Quality Certifications & Testing

Wenzhou Jixing Metal Materials Co., Ltd. maintains rigorous quality control systems and holds multiple international certifications ensuring that every Stainless Steel Coil Tube product meets or exceeds global standards.

Certifications Held