Standard

BS 2871 Part 3

ASTM B-111

DIN 1785

NFA 51 102

JIS H3300

IS 1545

Symbol

CN 110

C 68700

CuZn20 Al 1

CuZn Al 2

C 6820

CuZn 21 Al 2 As

Cu

76.0 – 78.0

76.0 – 79.0

76.0 – 79.0

76.0 – 79.0

76.0 – 79.0

76.0 – 78.0

Al

1.8 – 2.3

1.8 – 2.5

1.8 – 2.3

1.8 – 2.5

1.8 – 2.5

1.8 – 2.3

Pb

0.07

0.07

0.07

0.07

0.07

0.07

Ni

-

-

0.1

-

-

-

Fe

0.06

0.06

0.07

0.06

0.06

0.06

Zn

Remainder

Remainder

Remainder

Remainder

Remainder

Remainder

As

0.02 – 0.06

0.02 – 0.06

0.02 – 0.035

0.02 – 0.06

0.02 – 0.06

0.02 – 0.06

P

-

-

0.1

-

-

-

Total impurities Max.

  0.30

  -

  0.1

0.30

-

0.30

Condition

M

TA

O

O61

F 39

F34

-

O

O

TA

D

Yield

Strength

N/ mm2

-

-

-

125

150-230

120-180

-

-

400 Mps Max

355 Mps Min

415 Mps Min

Tensile

N / mm2

-

-

-

345

390 Min

340 Min

-

375

-

-

-

Elongation

%

-

-

-

-

45 Min

55 Min

-

40

85 Max

80-110

130 Min

Hardness HV 5

150 Min

85-110

75 Min

-

-

80-130

-

-

-

-

Grain size

Mm (75X)

0.05 Max

.010 - .045

-

.010 - .045

.010 - .045

.010 - .045

A Copper Zinc Alloy containing Aluminium and small amount of arsenic which is added as an inhibitor against dezincification. Inhibited Aluminium Brass resists the action of high velocity salt and brackish water and is commonly used for condenser tube. The outstanding characteristics of Aluminium Brass is the high resistance to impingement attack. Tubes of this alloy are recommended for use in marine and land power stations where cooling water velocity are high and where inhibited admiralty brass has failed from impingement.

Guide to the selection of tube material:

Sea Water :

1. Dissolved salts more than from 2000 ppm.
2. Suspended solids more than 30 ppm.
3. H2S or Ammonia is less than 1 ppm.

Permissible average velocity of water 2.0 – 2.5 meters/sec.