C11000 electrolytic tough pitch (ETP) copper pipe is a high-purity copper tube containing 99.9% or more copper. Its very low residual impurity level, electrical conductivity close to 100% IACS and high thermal conductivity make it the reference material for electrical conductors, heat-transfer circuits and general industrial tubing where consistent performance is required.
What Is C11000 Electrolytic Tough Pitch Copper Pipe?
C11000 is produced by the direct conversion of selected refined cathodes under carefully controlled melting and casting conditions, so that residual oxygen stays inside a narrow band and the metal retains its characteristic tough pitch structure. Annealed C11000 is soft and ductile: it can be bent, flared, expanded, soldered, brazed, drilled and welded to fit almost any design specification. Density is 8.89 g/cm³ and the melting range is 1065-1083 °C.
Because the chemistry is tightly controlled, mechanical behaviour and conductivity are reproducible from lot to lot, which matters for brazed assemblies, wound coils and long instrument runs where a single weak joint or a localised conductivity drop is unacceptable.
Chemical Composition and Impurity Limits
C11000 is specified by its copper plus silver content and by tight upper limits on residual elements. Typical values are listed below.
| Element | Limit |
|---|---|
| Copper + Silver (Cu + Ag) | ≥ 99.90% |
| Tin (Sn) | ≤ 0.002% |
| Zinc (Zn) | ≤ 0.005% |
| Lead (Pb) | ≤ 0.005% |
| Nickel (Ni) | ≤ 0.005% |
| Iron (Fe) | ≤ 0.005% |
| Antimony (Sb) | ≤ 0.002% |
| Sulfur (S) | ≤ 0.005% |
| Arsenic (As) | ≤ 0.002% |
| Bismuth (Bi) | ≤ 0.001% |
| Oxygen (O) | ≤ 0.06% |
| Total of other impurities | ≤ 0.10% |
Mechanical Properties and Tempers
Mechanical values depend strongly on temper. The table below gives representative ranges for the annealed (O) and cold worked (H01/H02) conditions.
| Property | Annealed (O) | Cold worked (H01/H02) |
|---|---|---|
| Tensile strength | 235-275 MPa | 290-410 MPa |
| Yield strength | 70-100 MPa | 100-390 MPa |
| Elongation | 40-50% (δ10) | 5-10% (δ5) |
| Hardness | 40-75 HV | 80-110 HV |
| Elastic modulus | 115-117 GPa | 115-117 GPa |
| Shear strength | 150-230 MPa | 150-230 MPa |
| Poisson ratio | 0.34 | 0.34 |
Size Range, Standards and Supply Forms
| Parameter | Range |
|---|---|
| Outside diameter (OD) | 2 mm - 914 mm |
| Wall thickness (WT) | 0.2 mm - 120 mm |
| Length | 1 m - 6 m, cut to order |
| Forms | Round, square, rectangular, straight length or coil |
| Condition | Soft annealed, half hard or drawn |
C11000 copper tube is commonly ordered against the following specifications:
ASTM B280 - seamless copper tube for air conditioning and refrigeration service
ASTM B152 - copper sheet, strip, plate and rolled bar, used as a chemistry reference
JIS H3300 - copper and copper alloy seamless tubes
EN 12735-1 - seamless copper tubes for air conditioning and refrigeration
EN 13348 - copper tubes for medical gas and vacuum systems
AS/NZS 1571 - copper tubes for plumbing, gasfitting and drainage
ANSI/ASME B16.22 - wrought copper and copper alloy solder-joint pressure fittings
Typical Applications and Service Considerations
Bus bars, bus conductors and hollow conductors in electrical power installations
Ground straps, wave guides and high resistance ratio cryogenic shunts
Welding fixtures, anodes and transistor component bases
Inductors, automotive rectifiers and glass-to-metal seals
Heat exchanger, condenser and instrument tubing in clean water circuits
ETP copper resists weathering, potable water, most soils and many non-oxidising mineral and organic acids, and it can be used underground because it resists soil corrosion. It is not the first choice for strongly oxidising or ammoniacal media, where higher-alloy copper grades are preferred.
Frequently Asked Questions
Q: What copper content does C11000 ETP pipe contain?
C11000 is specified with a copper plus silver content of at least 99.90%, with oxygen held to 0.06% maximum and individual impurities typically below 0.005%.
Q: What sizes of C11000 copper pipe are available?
Standard production covers outside diameters from 2 mm to 914 mm, wall thickness from 0.2 mm to 120 mm and lengths from 1 m to 6 m, with intermediate sizes made to order.
Q: Is C11000 copper tube suitable for refrigeration circuits?
Yes. ASTM B280 and EN 12735-1 cover copper tube for air conditioning and refrigeration, and the annealed temper bends and flares easily on site.
Q: How does temper change the mechanical properties?
Annealed tube reaches 235-275 MPa tensile with 40-50% elongation, while the hard H01/H02 temper rises to 290-410 MPa tensile with 5-10% elongation.
Q: Which welding processes are recommended for ETP copper?
Soldering, brazing, gas shielded arc welding, oxyacetylene welding and butt welding are suitable; coated metal arc, spot and seam welding are not recommended.
Q: How should C11000 pipe be stored before installation?
Keep it dry, indoors and clear of the ground on timber or plastic dunnage, so that the bright surface is preserved and no stray workshop metal contacts the tube.
