Brass Parts India is a specialist copper casting manufacturer and exporter in India, producing a comprehensive range of precision copper castings and CNC machined copper parts for the electrical power, switchgear, transformer, welding, chemical, and general engineering industries worldwide. Our copper casting facility combines controlled-atmosphere melting, multiple casting processes, and in-house CNC machining to deliver high conductivity copper castings that meet the most demanding electrical, thermal, and mechanical performance requirements.
From pure ETP copper sand castings for busbar connectors, through investment cast copper components for precision electrical contacts, to centrifugally cast copper rings for induction motors and oxygen-free copper (OFHC) machined parts for vacuum and high-temperature applications — we offer the complete spectrum of copper casting and machining services under ISO 9001:2015 quality management.
Copper Alloy Grades for Casting and Machining
We work with the full range of commercially pure copper grades and copper alloys suitable for casting and precision machining. The table below summarises the key grades, international standards, properties, and typical applications:
| Grade / Common Name | UNS / CDA No. | BS EN / DIN | IS / ASTM | Conductivity (% IACS) | Key Properties & Applications |
|---|---|---|---|---|---|
| ETP Copper (Electrolytic Tough Pitch) | C11000 / CDA 110 | CW004A / Cu-ETP / 2.0060 | ASTM B152 / IS 191 | ≥ 100% | Standard high-conductivity copper; busbar connectors, contact blocks, terminal lugs, cable connectors, electrode holders, earthing components |
| OFHC Copper (Oxygen-Free High Conductivity) | C10200 / CDA 102 | CW008A / Cu-OF / 2.0070 | ASTM B170 | ≥ 101% | No residual oxygen; immune to hydrogen embrittlement; vacuum equipment, high-temperature service, waveguides, power tubes |
| OFE Copper (Oxygen-Free Electronic) | C10100 / CDA 101 | CW009A / Cu-OFE | ASTM B170 Grade 1 | ≥ 101.5% | Highest purity (99.99%+ Cu); semiconductor equipment, superconductor components, electron beam applications |
| DHP Copper (Deoxidised High Phosphorus) | C12200 / CDA 122 | CW024A / Cu-DHP / 2.0090 | ASTM B152 / IS 7811 | ~85% | Phosphorus-deoxidised; excellent weldability and brazability; plumbing fittings, heat exchanger headers, fabricated assemblies |
| Silver-Bearing Copper | C10400 / C10500 | CW013A / Cu-Ag | ASTM B152 | ≥ 100% | Ag raises softening temperature to 300°C+; commutator segments, overhead contact wire clamps, traction current collectors |
| Chromium Copper (CuCr1) | C18200 / CDA 182 | CW105C / CuCr1 / 2.1291 | ASTM B768 | 80–85% | Age-hardenable; high strength + moderate conductivity; resistance welding electrodes, stud welding tips, spot welding tips, electrical contacts |
| Chromium-Zirconium Copper (CuCrZr) | C18150 / CDA 182 | CW106C / CuCrZr / 2.1293 | ASTM B768 | 80–82% | Higher strength age-hardened Cu; resistance welding electrodes, induction motor end-rings, high-current switch contacts |
| Beryllium Copper (CuBe2) | C17200 / CDA 172 | CW101C / CuBe2 / 2.1247 | ASTM B570 | 22–28% | Highest strength copper alloy; springs, contacts, non-sparking tools, precision parts requiring fatigue resistance — machined parts only (not cast) |
| Tellurium Copper (CuTeP) | C14500 / CDA 145 | CW118C / CuTeP / 2.1546 | ASTM B301 | 93–95% | Free-machining copper; fastest cutting copper; electrical contacts, connectors, switches, CNC machined electrical parts |
| Sulphur Copper (CuSP) | C14700 / CDA 147 | CW114C / CuSP | ASTM B301 | 96% | Free-machining; screw machine parts, connectors, terminals — high-speed CNC machining |
Copper Casting Processes We Use
Sand Casting of Copper
Copper sand casting is the most versatile and cost-effective process for producing medium-to-large copper components in low-to-medium volumes. We use chemically-bonded (furan and phenolic) sand moulds with carefully designed venting systems to minimise gas porosity — the primary challenge in casting pure copper. Sand casting is ideal for busbar connectors, contact blocks, transformer connections, electrode holders, earthing pads, and custom copper current-carrying components.
Investment Casting of Copper
Copper investment casting (lost wax) produces highly accurate, near-net-shape copper components with excellent surface finish and the ability to incorporate complex geometry, thin walls, and fine internal passages. This process is preferred for precision electrical connectors, switchgear contact components, bus clamp bodies, grounding clamps, instrumentation components, and custom copper terminal lugs requiring tight dimensional tolerances.
Centrifugal Casting of Copper
Copper centrifugal casting produces dense, porosity-free cylindrical components with consistently high electrical conductivity throughout the cross-section. The centrifugal force effectively eliminates gas and shrinkage porosity, which is critical for high-conductivity applications. Copper centrifugal castings are used for induction motor end rings, generator rotor sleeves, bus tube sections, and short-circuit rings.
Gravity Die (Permanent Mould) Casting of Copper
Copper gravity die casting uses metal (graphite or steel) moulds for improved dimensional consistency and surface finish versus sand casting. Preferred for medium-to-high volume production of repeating copper components such as cable lugs, connection sockets, arcing contact tips, and terminal connectors.
CNC Machined Copper Parts
Brass Parts India’s CNC machining facility produces precision copper machined parts from copper castings, copper bar, rod, and tube stock. Our machining capabilities for copper components include:
- CNC Turning: Precision turning of copper components to ±0.01 mm — busbars, bus clamps, contact pins, terminal lugs, spigots, reducer sockets
- CNC Milling: Flat-faced connectors, copper bus joints, slot-machined contact pads, complex profile copper components
- Drilling & Tapping: All metric, BSP, NPT, UNC and UNF threads — fixing holes, cable entry holes, earthing stud tapping
- Slotting & Broaching: T-slots, bayonet slots, keyways for copper bus clamps and expansion joints
- Silver Plating & Tin Plating: In-house or approved subcontract silver and tin electroplating for contact resistance reduction and oxidation protection
- Drilling of Conductor Holes: Precision-drilled conductor entry holes, NEMA bolt-hole patterns, custom hole configurations
Applications of Copper Castings and Machined Parts
- Electrical Switchgear: Contact blocks, arcing contacts, bus clamps, earthing pads, fixed contact arms — C11000 ETP or C10200 OFHC
- Power Transformers: LV winding connectors, tap changer contacts, terminal lugs, neutral links, bushing connectors — C11000 ETP
- Busbars & Power Distribution: Tee-off clamps, splice plates, expansion joints, cable lugs, bi-metallic clamps — C11000 ETP, silver or tin plated
- Welding Equipment: Electrode holders, contact tips, welding torch bodies, nozzles, tip adaptors — C18200 CrCu (welding electrodes), C11000 (torch bodies)
- Electric Motors & Generators: Commutator segments, slip ring components, rotor end rings, stator connector bars — C11000 ETP, C10400 silver-bearing
- Railway & Traction: OHL (Overhead Line) connectors, rail bonds, third-rail clamps, pantograph contact strips, cable lugs — C11000, C10400
- Induction Heating: Induction coil connectors, work coil adapters, quench block connectors, bus links — C11000 or C18150 CuCrZr for high-current/thermal cycling service
- Chemical & Electrochemical: Electrolytic cell bus connectors, plating rectifier connections, aluminium smelter bus clamps — C11000 ETP, heavy-section castings
- Grounding & Earthing: Earth rods, earth clamps, bonding connectors, equipotential bonding strips — C11000 ETP, tinned or bare
Technical Capabilities — Copper Casting & Machining
| Parameter | Capability |
|---|---|
| Casting Processes | Sand Casting, Investment (Lost Wax) Casting, Centrifugal Casting, Gravity Die Casting |
| Copper Grades | C11000 (ETP), C10200 (OFHC), C10100 (OFE), C12200 (DHP), C10400 (Ag-bearing), C14500 (Tellurium Cu), C18200 (CrCu), C18150 (CuCrZr) |
| Weight Range (Cast) | 20 grams to 200 kg per piece |
| Conductivity Testing | In-house eddy-current conductivity meter (% IACS); reported on MTC |
| Chemistry Verification | OES (Optical Emission Spectrometry) on every heat; full elemental analysis |
| Machining Tolerance | ±0.01 mm CNC turned; ±0.02 mm CNC milled |
| Surface Treatment | Silver plating (Ag 5–25 μm), Tin plating (Sn 5–15 μm), Nickel plating, Passivation, Bare bright finish |
| Compliance | RoHS 2 | REACH | ISO 9001:2015 | EN 10204 3.1 MTC |
| NDT | Dye Penetrant Testing, Hydrostatic pressure test, Dimensional inspection (CMM) |
Frequently Asked Questions — Copper Casting & Machined Parts
Q1. What is the best copper grade for electrical busbars and switchgear components?
ETP Copper (C11000 / CW004A) is the industry standard for cast busbar connectors, switchgear contacts, and current-carrying components. With conductivity ≥ 100% IACS, it provides the optimal balance of electrical performance, castability, machinability, and cost. For applications where hydrogen embrittlement at elevated temperature is a risk (above 500°C in reducing atmospheres), OFHC Copper (C10200) is specified instead.
Q2. How do you prevent porosity in pure copper castings?
Pure copper is notoriously susceptible to gas porosity due to its high affinity for dissolved hydrogen and the steam reaction (Cu₂O + H₂ → 2Cu + H₂O) during solidification. We control porosity through: selection of dry, clean charge materials; controlled deoxidation practice; nitrogen or argon cover gas during melting; proper mould design with generous risers and progressive solidification; controlled pouring temperature; and mould venting design. All castings are inspected by dye penetrant testing, and pressure testing is available for pressure-critical components.
Q3. What is the advantage of Tellurium Copper (C14500) for machined parts?
Tellurium Copper (C14500 / CuTeP) is the free-machining copper — tellurium additions (0.4–0.7%) create fine, discontinuous telluride particles in the matrix that act as chip-breakers, dramatically improving machinability (rated ~90% of free-cutting brass) while maintaining 93–95% IACS electrical conductivity. It is the preferred material for high-precision CNC-turned copper components such as electrical contacts, switch components, connectors, and terminals where close tolerances and high-volume production are required.
Q4. Can copper castings and machined parts be silver-plated?
Yes — silver plating of copper components is one of our standard value-added services. Silver plating (typically 5–25 μm thick) on copper switchgear contacts, busbar connectors, and transformer terminals dramatically reduces contact resistance, prevents surface oxidation, and maintains low-resistance electrical joints throughout service life. We supply silver-plated copper castings and machined parts widely to switchgear OEMs, transformer manufacturers, and busbar fabricators in the UK, Europe, USA, and Australia.
Q5. What is Chromium Copper (C18200) and when is it used?
Chromium Copper (C18200 / CW105C / CuCr1) is an age-hardenable copper alloy containing 0.6–1.2% chromium. After solution treatment and precipitation hardening, it achieves tensile strengths of 350–450 MPa with 80–85% IACS conductivity. It is the material of choice for resistance welding electrodes (spot weld caps, seam weld wheels, projection weld pads), stud welding contact tips, and high-current electrical contacts where both high strength (to resist electrode deformation) and high conductivity (to minimise bulk heating) are simultaneously required.
Q6. Do you supply OFHC copper machined parts for vacuum applications?
Yes. We supply OFHC copper (C10200 / CW008A) machined parts for vacuum furnace components, electron beam equipment, vacuum interrupter contacts, and particle accelerator components. OFHC copper’s freedom from oxygen eliminates hydrogen embrittlement risk at elevated temperatures and ensures extremely low outgassing rates essential for high-vacuum service. All OFHC parts are supplied with full material certification and are available with electropolishing or bright annealing for ultra-clean surface conditions.
Related Terms — Copper Casting & Machined Parts
Process & Material Terms
Copper sand casting | Copper investment casting | Copper centrifugal casting | Copper gravity die casting | CNC machined copper parts | Precision copper machining | Copper casting foundry India | High conductivity copper casting | ETP copper casting | OFHC copper casting | Oxygen-free copper machined parts | DHP copper casting | Tellurium copper machining | Chromium copper machined parts | CuCrZr machined parts | Silver-plated copper parts | Tin-plated copper components
Grade & Standard Terms
C11000 copper casting | C10200 copper | C10100 OFE copper | C12200 DHP copper | C14500 tellurium copper | C18200 chromium copper | C18150 CuCrZr | CW004A copper | CW008A copper | ASTM B152 copper | BS EN 1977 copper | DIN 1787 copper | 100% IACS copper | IS 191 copper casting
Application Terms
Copper busbar connector casting | Copper switchgear component | Copper transformer connector | Copper welding electrode | Resistance welding tip copper | Copper earthing clamp casting | Copper cable lug casting | Copper commutator segment | Copper induction motor ring | Copper bus clamp | Copper grounding connector | Copper OHL connector | Copper traction fitting | Silver-plated copper switchgear | Copper casting exporter India
