Explore our foundational range of precision fabricated products engineered for global structural and electrical compliance.
Leveraging advanced metallurgical processing, global standard compliance, and decades of manufacturing leadership to deliver high-gain value to our international partners.
We supply copper bars using raw materials with a minimum copper content of 99.99% (C10100/C10200) and 99.90% (C11000 ETP). This level of purity ensures peak electrical conductivity and reliable mechanical formability under extreme thermal stresses.
Equipped with continuous upward casting lines, cold-drawing systems, and automated extrusion facilities, we deliver dimensional tolerances that surpass ASTM B187 and DIN EN 13601 specifications.
Every delivery undergoes strict testing. Our protocols include spark-source emission spectroscopy, eddy current testing, micro-hardness validation, and electrical conductivity testing using eddy current instruments.
Modern electrical infrastructure and rapid electrification place strict requirements on conductive components. High-purity copper bars represent a key component in switchgear assembly, electric vehicle drivetrains, industrial transformer windings, and energy storage grids. Achieving reliable electrical performance requires a deep understanding of metallurgy, production consistency, and strict quality control.
As a leading hub for metal fabrication and metallurgical refinement, China’s industrial ecosystem offers distinct advantages for global copper bar procurement:
Selecting the correct grade of copper is critical to balancing performance and cost. The table below outlines our primary production grades and their typical applications:
| Alloy Grade (US/EU) | UNS Number | Copper Purity (Min) | IACS Conductivity | Primary Industrial Applications |
|---|---|---|---|---|
| ETP (Electrolytic Tough Pitch) | C11000 / CW004A | 99.90% | 100.0% - 101.5% | Electrical busbars, switchgear panels, motor windings, industrial earthing. |
| OF (Oxygen-Free) | C10200 / CW008A | 99.95% | 101.0% | Vacuum electronics, high-vacuum seals, superconductors, busbars requiring hydrogen brazing. |
| OFE (Oxygen-Free Electronic) | C10100 / CW009A | 99.99% | 101.5% | Semiconductor packaging, high-end scientific equipment, cryogenic systems. |
| DHP (Phosphorus Deoxidized) | C12200 / CW024A | 99.90% | 80% - 90% | Heat exchangers, refrigeration piping, structural architectural elements. |
Providing reliable performance across critical power generation, distribution, and storage applications.
EV drivetrains require high current distribution in confined spaces. Our custom bent and laminated insulated copper busbars provide reliable current routing inside battery packs, inverter systems, and megawatt charging stations, helping manage temperature rise under rapid charge cycles.
Reliable power distribution relies on contact interfaces that resist oxidation. We provide tin-plated and silver-plated copper bars that minimize contact resistance, prevent galvanic corrosion at joint connections, and withstand short-circuit stresses in gas-insulated switchgear (GIS).
Utility-scale inverters and wind turbine generators operate under variable environmental loads. Our high-fatigue copper solutions resist physical vibrations and environmental moisture, ensuring uninterrupted energy transfer to step-up transformers.
Heavy manufacturing requires high power transfer efficiency. Our clean-edge, burr-free rectangular copper bars prevent dielectric puncture in transformer winding systems, reducing localized eddy-current heating and improving overall efficiency.
High-density computing facilities need continuous, stable power. Solid-core copper busways replace thick cable runs to maximize cooling airflow and simplify system expansions in modern server facilities.
Chlor-alkali plants and metal smelting systems require hundreds of kiloamperes of continuous direct current. Our heavy-gauge, custom-machined copper busbar systems are designed to minimize voltage drops and reduce operational costs.
A Trusted Global Partner for Advanced Metal Materials & Precision Manufacturing
Ningbo Puppet Steel Co., Ltd. is a professional Steel Sheet Manufacturer | Cold Rolled, Hot Rolled & Galvanized Steel Supplier committed to providing high-quality steel products and customized metal solutions for customers worldwide. Serving industries such as construction, infrastructure, manufacturing, automotive, energy, home appliances, and industrial equipment, the company has built a strong reputation for reliable products and consistent service.
Located in Ningbo, China, Puppet Steel operates advanced processing and manufacturing facilities equipped with modern production lines and precision quality inspection systems. The company specializes in a comprehensive range of steel products, including cold rolled steel sheets, hot rolled steel sheets, galvanized steel sheets, galvalume steel sheets, prepainted steel sheets, carbon steel sheets, structural steel sheets, and customized steel processing solutions.
With extensive industry experience, the company offers flexible OEM and customized manufacturing services to meet various project requirements. From material selection and cutting to surface treatment and packaging, every production stage is carefully managed to ensure product consistency, dimensional accuracy, and long-term performance. Strict quality control procedures are implemented throughout the manufacturing process to comply with international standards and customer specifications.
Puppet Steel focuses on delivering durable, corrosion-resistant, and cost-effective steel products suitable for demanding applications in both domestic and international markets. The company maintains long-term partnerships with contractors, distributors, wholesalers, fabricators, and industrial manufacturers across North America, Europe, Southeast Asia, the Middle East, and other global regions.
Driven by innovation, quality, and customer satisfaction, Ningbo Puppet Steel Co., Ltd. continuously invests in technology upgrades and production efficiency improvements. Through competitive pricing, stable supply capacity, timely delivery, and professional technical support, the company strives to become a trusted global partner for steel sheet manufacturing and metal material solutions.
Answers to complex engineering, chemical makeup, and supply chain questions.
In alternating current (AC) systems, current density tends to concentrate near the outer surface (skin) of the conductor. As frequency increases, the effective cross-sectional area of the bar decreases, raising AC resistance. For high-frequency harmonic applications, such as inverters or power supplies, thin rectangular copper bars or hollow profiles are preferred over round conductors to optimize the surface-area-to-volume ratio and control thermal losses.
Bare copper oxidizes over time when exposed to atmospheric moisture, forming a layer of copper oxide that increases joint resistance. Electroplated tin-plating provides reliable protection, maintains low contact resistance, prevents galvanic oxidation in aluminum-to-copper connections, and extends the service life of busbar systems in humid or corrosive industrial environments.
Electrolytic Tough Pitch (C11000 ETP) contains traces of cuprous oxide. When heated above 370°C in hydrogen atmospheres (such as brazing or gas welding), hydrogen can diffuse into the metal and react with the oxide to form water vapor pockets, leading to internal cracking (hydrogen embrittlement). For applications requiring extensive brazing or welding, oxygen-free copper grades (C10200 OF or C10100 OFE) are recommended.
We manufacture copper bars in compliance with international standards, including ASTM B187 (standard specification for copper bar, bus bar, and shapes), EN 13601 (copper and copper alloys for electrical purposes), and JIS H3140. Our typical thickness tolerances are controlled within +/-0.03mm, and width tolerances are held within +/-0.05mm.
High-precision processing, cutting, and welding solutions tailored for global industrial projects.
Puppet Steel
