TOBO Industrial (Shanghai) Co., Ltd., a leading manufacturer and global supplier of precision-engineered metal products, has announced a significant expansion of its HVAC/R component portfolio with the introduction of Copper-Nickel Alloy 3/8" AC Insulated Pancake Pair Coils, complemented by professional welding services for air conditioning and refrigeration applications. This integrated solution combines advanced corrosion-resistant materials with factory-applied insulation and value-added fabrication capabilities, delivering a comprehensive package for critical refrigerant line installations.
The Material Advantage: 90/10 Copper-Nickel Alloy
The new product line leverages the exceptional properties of UNS C70600 Copper-Nickel 90/10 alloy—a material renowned for its outstanding performance in demanding environments. With a composition of approximately 90% copper and 10% nickel, plus controlled additions of iron and manganese, this alloy offers superior corrosion resistance and mechanical strength compared to standard copper tubes .
Superior Corrosion Resistance: The alloy provides outstanding resistance to formicary corrosion ("ants' nest corrosion"), a pervasive failure mode in standard copper tubes caused by volatile organic compounds (VOCs) from insulation and building materials. It also demonstrates exceptional resistance to stress-corrosion cracking and pitting, particularly valuable for coastal and industrial installations .
Enhanced Mechanical Strength: The material delivers higher tensile strength (typically 275-450 MPa) and superior resistance to vibration-induced fatigue, which is critical for compressor discharge lines and components subject to constant operational stress. These properties ensure durability in demanding air conditioning and refrigeration systems .
Proven Longevity: Systems utilizing C70600 components have demonstrated service lives exceeding 30-40 years, offering exceptional total cost of ownership despite higher initial material costs .
The Pancake Pair Coil Format: Efficiency by Design
The 3/8" copper-nickel tubes are factory-insulated and co-wound into a compact, flat "pancake" pair coil. This design delivers transformative benefits for HVAC contractors and system designers:
Space Optimization: The flat pancake design reduces warehouse and service vehicle storage requirements compared to traditional round coils or rigid straight lengths, while also lowering shipping costs and carbon footprint.
Installation Efficiency: Pre-insulated coils significantly reduce installation time compared to traditional line set preparation, and the pre-paired liquid and suction lines at identical lengths eliminate measurement errors, ensuring proper system charge .
Factory-Applied Insulation: The tubes are insulated at the manufacturing facility with advanced closed-cell foam, eliminating variability and gaps common with field-applied insulation. The precision application ensures consistent thermal performance and reduces the risk of condensation damage .
Professional Welding Services: Complete Installation Support
TOBO complements the material supply with integrated professional welding services for copper-nickel tubes, addressing the complete spectrum of installation requirements :
Welding Capabilities:
TIG (GTAW) Welding: Precision welding with controlled heat input, ideal for thin-wall tubing and critical connections
Orbital Welding: Automated welding for high-purity applications requiring consistent, repeatable results
Silver Brazing: For standard refrigerant line connections
Quality Assurance: All welding procedures meet ASME Section IX requirements, with certified welders experienced in copper-nickel alloys and non-destructive testing available to validate joint integrity .
Industry Applications
The product serves essential functions across diverse HVAC/R applications, including residential and commercial air conditioning, mini-split and VRF systems, marine and coastal HVAC installations requiring extended service life with minimal maintenance, and industrial refrigeration systems where reliability is paramount .
Sustainability and Lifecycle Value
The adoption of C70600 tubes in HVAC/R applications aligns with sustainability objectives :
Extended Service Life: 30-40 year service life reduces replacement frequency and material consumption
Maintained Efficiency: Corrosion and fouling resistance preserve heat transfer efficiency throughout system lifetime
Reduced Leak Risk: Superior corrosion resistance minimizes refrigerant leakage and associated environmental impact
100% Recyclable: Copper-nickel alloys are fully recyclable without degradation of material properties
About TOBO Industrial (Shanghai) Co., Ltd.
TOBO is a professional manufacturer and exporter of precision-engineered metal products based in Shanghai, China. With robust production capacity and a commitment to metallurgical excellence, TOBO serves customers worldwide across HVAC/R, marine, energy, and industrial sectors. The company specializes in copper-nickel alloys, stainless steels, and associated products for demanding applications, with strict quality control and complete traceability .