| Main Tube Materials | Aluminium alloys are widely selected because they combine low density, good thermal conductivity, corrosion resistance, and suitability for extrusion and bending. | Common grades include 6061 and 6063 aluminium alloys, subject to the required strength, weldability, and forming process. | Electric vehicle battery packs, battery thermal-management assemblies, and compact coolant circuits. | Confirm alloy designation, temper, chemical composition, tensile properties, surface condition, and compatibility with the specified coolant. |
| Alternative Metal Materials | Stainless steel tubing is used when higher mechanical strength, temperature resistance, or corrosion resistance is required. | 304 and 316L stainless steel are commonly considered material options; the final choice depends on coolant chemistry and joining requirements. | Heavy-duty vehicles, special-purpose vehicles, high-vibration systems, and sections exposed to demanding operating conditions. | Evaluate weight, thermal conductivity, galvanic-corrosion risk, weldability, and total system cost before selecting stainless steel. |
| Tube Geometry | Manufacturers commonly supply round tubes, flattened tubes, bent tubes, and formed sections designed around the battery-pack layout. | Illustrative engineering ranges include approximately 6–20 mm outside diameter for round tubing and about 0.5–2.0 mm wall thickness, depending on design and alloy. | Cooling routes between modules, pack perimeter circuits, inlet and outlet manifolds, and connections to cold plates. | Dimensions must be validated against flow rate, pressure drop, packaging clearance, bend radius, and crash-safety requirements. |
| Manufacturing Processes | Typical production routes include extrusion, cold drawing, cutting, CNC forming, tube bending, flattening, brazing, laser welding, and mechanical joining. | High-volume programs generally use dedicated forming and inspection fixtures, while prototypes and low-volume programs rely more on flexible CNC and manual tooling. | Prototype development, pilot production, and serial production of battery thermal-management assemblies. | Request process-flow charts, control plans, first-article inspection records, and evidence of repeatable dimensional capability. |
| Connection and Sealing Methods | Common interfaces include aluminium or stainless-steel welded joints, brazed joints, crimped fittings, O-ring connections, and quick connectors. | Connection design is normally defined by tube material, coolant pressure, vibration exposure, serviceability, and available installation space. | Battery pack inlet and outlet ports, manifold connections, chiller interfaces, and vehicle-side coolant lines. | Check joint strength, seal-material compatibility, vibration durability, assembly force, service replacement requirements, and galvanic isolation. |
| Coolant Compatibility | Water-glycol mixtures are commonly used in electric-vehicle thermal-management systems; formulation and concentration are specified by the vehicle or battery-system designer. | A frequently used design reference is a water-glycol mixture in the approximate 30–50% volume range, although climate and system requirements can change this value. | Battery cooling loops, power-electronics cooling loops, and integrated vehicle thermal systems. | Verify compatibility with tube alloys, brazing flux residues, elastomers, coatings, inhibitors, and electrical-isolation requirements. |
| Leak and Pressure Testing | Production suppliers commonly combine visual inspection, dimensional inspection, pressure testing, pressure-decay testing, or helium leak detection. | Test pressure, allowable leakage rate, test duration, and test medium are project-specific and should be defined on the approved drawing or control plan. | Safety-critical battery coolant circuits where leakage can reduce cooling performance or create electrical hazards. | Require documented 100% end-of-line leak testing for serial parts when specified by the battery-system customer, with traceable test records. |
| Cleanliness Control | Battery cooling-pipe suppliers increasingly apply tube cleaning, filtered air or fluid flushing, capped storage, and controlled packaging. | Particle limits, residual oil limits, moisture limits, and cleanliness test methods should be agreed for each program rather than assumed to be universal. | High-voltage battery packs and systems containing narrow channels, valves, pumps, or sensitive thermal components. | Review cleaning validation, particle-count methodology, packaging protection, shelf-life controls, and contamination traceability. |
| Regional Manufacturing Landscape | Relevant supplier activity is concentrated around China’s automotive and metal-processing clusters, including the Yangtze River Delta, Pearl River Delta, Bohai Rim, and selected central provinces. | Regional capabilities vary from aluminium extrusion and tube forming to automated welding, brazing, inspection, and complete thermal-module assembly. | Domestic vehicle programs, export-oriented component production, battery-system integration, and contract manufacturing. | Assess logistics distance, local tooling support, export experience, supply-chain resilience, and ability to support customer audits. |
| Automotive Quality Systems | Suppliers serving vehicle and battery manufacturers commonly operate under ISO 9001; automotive programs frequently require IATF 16949 or equivalent customer-specific controls. | Typical quality documentation includes PFMEA, control plans, measurement-system analysis, process capability studies, change control, and traceability records. | Mass-production battery packs and vehicle platforms requiring stable process performance over long production cycles. | Certification alone is not sufficient; confirm the scope of certification covers the actual production site and relevant product processes. |
| Validation and Reliability Testing | Product validation commonly covers pressure, burst strength, vibration, thermal cycling, corrosion, coolant exposure, and dimensional stability after forming. | Test conditions should be derived from the vehicle duty cycle, coolant specification, environmental class, and customer validation plan. | Passenger vehicles, commercial vehicles, energy-storage systems, and battery packs exposed to wide temperature and vibration ranges. | Request validation reports, sample identification, test equipment calibration records, failure analysis, and corrective-action documentation. |
| Supply Capability Levels | China’s market includes specialised tube-forming suppliers, metal-component manufacturers, thermal-management integrators, and larger automotive-system suppliers. | Capability may range from prototype quantities to automated serial production; annual capacity should be confirmed for the exact geometry and process route. | Engineering samples, pilot builds, regional production, and high-volume vehicle programs. | Compare tooling ownership, minimum order quantity, ramp-up plan, equipment redundancy, capacity reservation, and second-source readiness. |
| Key Selection Metrics | Purchasing decisions are generally based on technical conformity, leak performance, cost, delivery reliability, engineering support, and quality-system maturity. | Important measurable items include dimensional capability, pressure-drop performance, leakage rate, burst pressure, corrosion resistance, yield rate, and on-time delivery. | Supplier qualification, design validation, sourcing, and long-term production management. | Use an approved drawing, specification, sample-validation plan, change-notification procedure, and clearly defined acceptance criteria. |
