Stainless Steel Coil Tube (Coiltube) — Model JX-1335

1. Product Overview

The Stainless Steel Coil Tube (Coiltube), catalogued as Product No. 1335 by Wenzhou Jixing Metal Materials Co., Ltd., is a precision-formed tubular product designed for thermal exchange applications, particularly in refrigeration and HVAC (Heating, Ventilation, and Air Conditioning) systems. The coil tube is manufactured from high-grade austenitic stainless steel and wound into a continuous helical configuration to maximize surface-area-to-volume ratio, thereby enhancing heat transfer efficiency.

This product has been extensively studied and validated in the context of direct-cooled dual-temperature dual-control refrigerator repair and maintenance, where its superior corrosion resistance, thermal conductivity, and mechanical durability make it an ideal replacement or upgrade component for evaporator coils and refrigerant circuit tubing.

2. Material & Properties

The coil tube is fabricated from Austenitic Stainless Steel, conforming to the following material standards:

3. Specifications

Parameter Specification Standard / Tolerance
Product No. 1335 —
Product Name Stainless Steel Coil Tube (Coiltube) —
Outer Diameter (OD) 6.0 mm / 8.0 mm / 12.7 mm / 15.88 mm (configurable) ± 0.1 mm
Wall Thickness (WT) 0.5 mm – 1.0 mm ± 0.05 mm
Coil Pitch (Helix Spacing) 10 mm – 25 mm (customizable) ± 0.5 mm
Coil Diameter 150 mm – 600 mm (as required) ± 2 mm
Tube Length (Uncoiled) 1 m – 50 m (continuous or cut-to-length) ± 10 mm
Material Grade SUS304 / SUS316L ASTM A269 / GB/T 12771
Surface Treatment Bright Annealed (BA) / Passivated GB/T 8898
Hydrostatic Test Pressure 2.0 – 5.0 MPa (depending on wall thickness) ASTM A269 §11
Refrigerant Compatibility R134a, R600a, R404A, R410A ISO 817
End Preparation Deburred, chamfered, or flared —

4. Manufacturing Process

The production of the JX-1335 Coil Tube follows a rigorous multi-stage manufacturing workflow to ensure dimensional accuracy, metallurgical integrity, and surface quality:

  1. Raw Material Inspection: Incoming stainless steel pipe stock is verified for chemical composition (spectroscopic analysis), mechanical properties, and surface condition in accordance with ASTM A269 / GB/T 12771 requirements.
  2. Cutting & Deburring: The pipe is cut to the specified coil length using precision plasma or saw-cutting methods, followed by mechanical deburring of both ends.
  3. Coil Forming (Helical Winding): The straight tube is wound onto a mandrel using a CNC (Computer Numerical Control) coil-winding machine to achieve the specified pitch, diameter, and uniformity. The forming process is performed at ambient temperature to preserve the work-hardened microstructure.
  4. Welding (if segmented): Where continuous-length limitations require segmented coils, orbital TIG (Tungsten Inert Gas) welding is employed with argon back-purging to achieve full-penetration, leak-tight joints with minimal heat-affected zone (HAZ).
  5. Stress Relief Annealing: The formed coil undergoes controlled thermal treatment (typically 850°C – 1050°C in a protective atmosphere) to relieve residual stresses introduced during forming, restoring full ductility and corrosion resistance.
  6. Pickling & Passivation: Surface scale and oxide layers are removed via acid pickling, followed by passivation treatment to establish a protective chromium oxide film (Cr₂O₃), ensuring long-term corrosion resistance.
  7. Hydrostatic Pressure Testing: Each coil is subjected to hydrostatic testing at the specified test pressure to verify leak-tightness and structural integrity.
  8. Final Inspection & Packaging: Dimensional verification (OD, WT, pitch, coil diameter) is performed using calibrated gauges and CMM (Coordinate Measuring Machine) equipment. Qualified products are packaged in moisture-proof cartons or wooden crates for shipment.

5. Applications

The JX-1335 Stainless Steel Coil Tube is engineered for demanding thermal management applications, with proven performance in the following sectors:

Notable Application — Refrigerator Repair: In the context of direct-cooled dual-temperature dual-control refrigerators, the coil tube serves as a critical repair component. When the original evaporator coil suffers from refrigerant leaks, mechanical damage, or degraded thermal performance due to corrosion, replacement with the JX-1335 stainless steel coil tube restores full cooling capacity. The stainless steel construction eliminates the risk of rust-induced failures common in carbon steel alternatives, significantly extending the service life of the refrigeration system.

6. Quality Certifications & Standards Compliance

Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality management system and holds the following certifications to ensure product excellence:

Every batch of JX-1335 Coil Tube is accompanied by a Mill Test Certificate (MTC) documenting chemical composition, mechanical test results, and dimensional verification data, ensuring full traceability and compliance with international standards.

7. Unique Selling Points