CuZn22 Al2 aluminium brass pipes are made from a copper zinc alloy with about 2% aluminium and a small proportion of arsenic, which is added to the alloy to increase its corrosion resistance. The aluminium provides protection from impingement in the fast flowing sea water and the arsenic provides protection from dezincification. These properties enable its use in marine condensers, power plant cooling system, seawater evaporators and industrial heat exchanger. In the old French standard NF A 51-102 it was designated as CuZn22Al2, currently it is ordered either as CuZn20Al2As (CW702R) or ASTM B111 C68700, but it still bears the same designation. Amardeep Steel is a manufacturer and supplier of seamless CuZn22 Al2 aluminium brass pipes in different diameters and dimensions for domestic and international industrial requirements.
Specifications of CuZn22 Al2 Aluminium Brass Pipe
Parameter | Specification |
|---|---|
Grade Name | CuZn22Al2 aluminium brass |
Governing Standards | NF A 51-102 equivalent; EN 12451 CuZn20Al2As (CW702R); ASTM B111 / ASME SB111 C68700; BS 2871 Part 3 CZ110; IS 1545 CuZn21Al2As |
Manufacturing Form | Seamless, cold-drawn round pipe and tube |
Outside Diameter (OD) | 6 mm to 108 mm |
Wall Thickness | 0.5 mm to 3.0 mm (BWG 22 to BWG 12) |
Length Options | Straight lengths up to 15 m, custom cut lengths, or bent U-tubes |
Temper / Condition | Annealed condition (standard for heat exchanger tubing); custom tempers on request |
Testing & Quality | Non-destructive eddy current or hydrostatic testing, flattening test, drift expansion test, residual stress test, grain size determination |
Certifications | EN 10204 3.1 mill test certificates; EN 10204 3.2 third-party inspection available upon request |
Chemical Composition of CuZn22 Al2 Aluminium Brass Pipe
Element (%) | CuZn22Al2 (NF A 51-102) | CuZn21Al2As (IS 1545) | Nominal Composition |
|---|---|---|---|
Copper (Cu) | 76.0 to 79.0 | 76.0 to 78.0 | 77.5 |
Aluminium (Al) | 1.8 to 2.5 | 1.8 to 2.3 | 2.0 |
Arsenic (As) | 0.02 to 0.06 | 0.02 to 0.06 | 0.04 |
Lead (Pb), max | 0.07 | 0.07 | — |
Iron (Fe), max | 0.06 | 0.06 | — |
Zinc (Zn) | Remainder | Remainder | ~20.5 |
Total Impurities, max | 0.3 | 0.3 | — |
Physical Properties of CuZn22 Al2 Aluminium Brass Pipe
Property | Metric Value | Imperial Value |
|---|---|---|
Density | 8.33 g/cm³ | 0.301 lb/in³ |
Melting Range | 932 to 971°C | 1,710 to 1,780°F |
Thermal Conductivity (20°C) | 100 W/m·K | 58 Btu/ft·h·°F |
Electrical Conductivity | 23% IACS | 23% IACS |
Electrical Resistivity | 7.5 µΩ·cm | 45.1 Ω·cmil/ft |
Coefficient of Thermal Expansion (20 to 300°C) | 18.5 µm/m·K | 10.3 µin/in·°F |
Specific Heat Capacity | 377 J/kg·K | 0.09 Btu/lb·°F |
Modulus of Elasticity (Young's) | 110 GPa | 16,000 ksi |
Modulus of Rigidity (Shear) | 41 GPa | 6,000 ksi |
Equivalent Grades of CuZn22 Al2 Aluminium Brass Pipe
Standard Body / Region | Grade Designation | Corresponding Technical Page |
|---|---|---|
NF A 51-102 (Former French) | CuZn22Al2 | |
EN 12451 (European Union) | CuZn20Al2As / CW702R | |
BS 2871 Part 3 (Former UK) | CZ110 | |
ASTM B111 / ASME SB111 (USA) | UNS C68700 | Standard condenser tube grade |
IS 1545 (India) | CuZn21Al2As | Current Indian Standard grade |
JIS H 3300 (Japan) | C6870T | Japanese industrial standard |
DIN 1785 (Former Germany) | CuZn20Al2 (2.0460) | Legacy German standard |
ISO 1554 | CuZn20Al2 | International organization standard |
Annealed Temper Names Across Standards of CuZn22 Al2 Aluminium Brass Pipe
Standard and grade | Annealed temper | Tensile, min | Other requirement |
|---|---|---|---|
ASTM B111 C68700 | O61 | 345 MPa (50 ksi) | Yield 125 MPa min |
EN 12451 CuZn20Al2As | R330 (confirm) | 330 MPa | Elongation 30% min |
JIS H 3300 C6870T | O | 375 MPa | Elongation 40% min |
NF A 51-102 CuZn22Al2 | Annealed | Not published | Hardness 80 to 130 HV5 |
Wall Thickness Chart of CuZn22 Al2 Aluminium Brass Pipe
BWG Gauge | Nominal Wall Thickness (Inches) | Nominal Wall Thickness (mm) |
|---|---|---|
BWG 12 | 0.109 in | 2.77 mm |
BWG 14 | 0.083 in | 2.11 mm |
BWG 16 | 0.065 in | 1.65 mm |
BWG 18 | 0.049 in | 1.24 mm |
BWG 20 | 0.035 in | 0.89 mm |
BWG 22 | 0.028 in | 0.71 mm |
Applications and Industrial Uses of CuZn22 Al2 Aluminium Brass Pipe
- Marine Surface Condensers
- Thermal Power Plant Condensers
- Seawater Cooling Systems
- Desalination Plant Heat Exchangers
- Shipboard Cooling Equipment
- Marine Evaporators
- Industrial Shell-and-Tube Heat Exchangers
- Petrochemical Cooling Systems
Frequently Asked Questions
1. What is CuZn22 Al2 aluminium brass pipe?
CuZn22 Al2 aluminium brass pipe is a copper-zinc alloy tube containing approximately 2% aluminium and a small arsenic addition, designed for heat exchangers and marine condensers.
2. What is the difference between CuZn22Al2 and CuZn20Al2As?
They name the same aluminium brass alloy. CuZn22Al2 is the old French designation, while CuZn20Al2As (CW702R) is the EN 12451 designation. Their specified composition limits differ slightly between standards.
3. Does CuZn22Al2 contain 22% aluminium?
No. The number 22 refers to zinc, not aluminium. CuZn22Al2 contains approximately 2% aluminium and typically around 20–21% zinc.
4. Is aluminium brass the same as aluminium bronze?
No. Aluminium brass is a copper-zinc alloy containing approximately 2% aluminium, whereas aluminium bronze contains around 5% or more aluminium and little or no zinc.
5. Are CuZn22Al2 aluminium brass pipes seamless?
Yes, CuZn22Al2 aluminium brass pipes are manufactured as seamless tubes, commonly using extrusion and cold drawing for heat exchanger applications.
6. What is the Indian equivalent of CuZn22Al2?
IS 1545 identifies the related aluminium brass grade as CuZn21Al2As, with copper content of 76.0–78.0% and aluminium content of 1.8–2.3%.
