Explore our high-performance copper tubes, capillary coils, drier filters, and vital refrigeration system accessories optimized for domestic and commercial HVAC/R applications.
Ningbo Taojun Refrigeration Equipment Co., Ltd. is strategically situated in Xiangshan, Ningbo, a prominent coastal engineering and industrial hub. Founded in 1988, our corporate heritage traces back to the prestigious Xiangshan Refrigeration Accessories Factory of Zhejiang University. This academic linkage endowed our manufacturing practices with rigorous technical foundations from the very beginning.
For more than 35 years, Taojun has committed itself to the design, research, development, and high-volume production of core HVAC/R components, including copper capillary tubes, filter driers, check valves, air conditioning valves, condensers, brass accessories, and specialty cabling connectors. In 2021, our technical breakthroughs were recognized with the national High-Tech Enterprise status, consolidating our position as an industry pioneer.
Through collaborative initiatives, our R&D team consists of 15 senior design engineers, including doctorates and researchers from the University of Science and Technology of China (USTC). Our product ecosystems meet the strictest global regulatory mandates, having successfully secured ISO9001:2015 Quality Management validation, EU RoHS environmental compliance directives, and US UL safety listings.
In refrigeration and air conditioning circuits, the copper capillary tube acts as a critical throttling mechanism. Its primary function is to restrict the high-pressure liquid refrigerant leaving the condenser, inducing a pressure drop and regulating flow directly into the evaporator. Achieving an exact pressure drop requires precise control over the tube's inner diameter (ID), wall thickness, internal cleanliness, and concentricity.
We construct our capillary tubes using C12200 Deoxidized High Phosphorus (DHP) Copper (containing at least 99.9% Pure Copper and 0.015% to 0.040% Phosphorus). This alloy provides excellent grain structure stability, high thermal conductivity, and prevents hydrogen embrittlement during subsequent brazing or welding. It is fully compliant with standards including ASTM B280, ASTM B360, and EN 12735-1/2.
| Parameter | Standard Specification | Taojun Precision Capability | Testing Methodology |
|---|---|---|---|
| Outer Diameter (OD) Range | 1.2 mm – 4.5 mm | ± 0.02 mm (High Precision Option Available) | Laser Micrometer Inspection |
| Inner Diameter (ID) Range | 0.5 mm – 3.0 mm | ± 0.01 mm | Air Flow & Nitrogen Flow Testing |
| Wall Thickness Tolerance | 0.35 mm – 1.2 mm | ± 5% | Ultrasonic Thickness Measurement |
| Internal Cleanliness (Residue) | < 0.038 g/m² (ASTM B360) | < 0.015 g/m² (Ultra-Clean Process) | High-Pressure Solvent Wash + Gravimetric Test |
| Tensile Strength (Hardness) | O (Annealed) to H (Hard) | Tailored (195 – 345 MPa) | Microhardness Vicker's Tester |
At Taojun, our manufacturing facilities integrate automation, digital monitoring, and data collection. Our smart factory infrastructure features a unified Manufacturing Execution System (MES), enabling real-time tracking of every production batch from raw copper rod casting to final vacuum sealing.
Our core multi-pass drawing benches are imported directly from Germany, allowing continuous reduction of capillary tubing without micro-fissures, yielding smooth, blemish-free internal bores.
Our automated lines feature CCD dual-camera inspection systems that detect surface scratches, structural abnormalities, and diameter variations, automatically rejecting non-conforming items.
We subject each capillary joint and copper filter drier assembly to high-pressure nitrogen tests and vacuum helium mass spectrometry, maintaining an exceptional 99.95% leak-free integrity rate.
Our copper capillary assemblies are custom engineered to solve fluid control challenges across diverse refrigeration markets.
Highly calibrated capillary coils configured to absorb heat quickly. Often bundled with our custom-welded 10g/15g/20g copper filter driers to remove moisture and acids efficiently.
Engineered to withstand cycling stresses and prevent mechanical fatigue under high thermal load changes. Ideal for standard liquid line integration.
Compact assemblies designed to withstand vibration and temperature fluctuations. Fully compliant with RoHS, REACH, and environmental directives.
Designed for ultra-low temperature applications (down to -86°C) using hydrocarbon refrigerants (R290, R600a), where clean capillary bores are essential to prevent blockage.
A timeline highlighting our path from a university laboratory partner to a global OEM/ODM manufacturer.
Established as Xiangshan Refrigeration Accessories Factory of Zhejiang University. Our engineering procedures were designed in partnership with leading thermodynamic laboratories.
Transitioned to advanced drawing benches and integrated our MES intelligent workshop management system, securing ISO9001:2008 validation.
Scaled production lines to supply global domestic appliance brands, delivering custom copper assemblies to over 50 countries with digital traceability.
We believe that a global brand is supported by a strong corporate culture. We understand that culture is formed through Impact, Infiltration, and Integration. Our development has been driven by core values: Honesty, Innovation, Responsibility, and Cooperation.
We adhere to the principles of integrity-focused management, quality first, and a solid reputation. This commitment remains a key driver of our competitiveness.
Innovation is the core of our culture. We continually improve our design concepts, production technologies, and management practices to adapt to market needs.
We maintain a strong sense of responsibility to our clients and partners, ensuring quality across all stages of production.
We work closely with partners to build long-term relationships, integrating resources and utilizing expert capabilities to deliver mutual value.
Over the years, we have built trusted relationships with global appliance manufacturers, including Haier, Xinfei, Midea, Gree, Whirlpool, Electrolux, and Huarui. Our export networks span Europe, North America, South America, Southeast Asia, the Middle East, and Africa.
We support partners with a low 500-unit MOQ, comprehensive technical training, and an responsive engineering support window.
Our manufacturing processes comply with strict quality standards to ensure consistency and reliability.
Ningbo Taojun Refrigeration Equipment Co., Ltd. maintains official GB/T19001-2016/ISO9001:2015 certification (Registration No.: 41325Q00065R0S). Our certification is verifiable via the Certification and Accreditation Administration of the People's Republic of China (CNCA) and partner verification networks.
Additionally, we subject our products to environmental and durability testing, including high-low temperature cycles (500 hours at 75°C to -35°C), thermal shock testing (10°C to 90°C), and damp heat testing. This rigorous approach ensures a low operational defect rate across all products.
ISO 9001 Certificate
Detailed Certification Scope
As global HVAC/R standards shift toward natural, low-GWP (Global Warming Potential) refrigerants like propane (R290) and carbon dioxide (R744), the technical demands on copper capillary assemblies and filter driers are changing. Our engineering team actively develops solutions to meet these future requirements.
Transcothermal CO₂ systems run at operating pressures exceeding 120 bar. We design specialized heavy-wall C12200 copper tubes and custom microbore capillary solutions to ensure reliability under high pressures.
We are testing internal nano-coatings designed to prevent oil logging and particulate adhesion inside micro-bore tubes, which helps maintain system efficiency over years of operation.
We are working toward 100% recyclable, halogen-free packaging and optimizing our closed-loop copper scrap reclamation processes to support circular manufacturing initiatives.
Technical answers to common questions about selecting, processing, and sourcing copper capillary tubes.
Browse our complete portfolio of refrigeration parts, including bundy tubes, filter driers, receiver tanks, and AC fittings.
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