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ALUMINA CEMENT
As the steel manufacturing, ceramic and heavy and chemical industries develops, the demand for the refractory materials
is steadily growing. And the refractory materials now tends to take the form of non-shaped refractory materials such as
castable
 
And the importance of alumina cement that is used mainly as binder for castable
refractory materials is being highlighted ever more. SEKYUNG CORPORATION
pays extreme attention to the selection of the materialsand applies a strict quality
control procedure for the production of alumina cement. Melted or sintered at high
temperature, its excellent quality is gaining recognitionsfrom both home and
abroad.
 

◎ UAC50

 - General characteristics

  • Hydraulic cement with approximately 50% alumina
  • Does not contain any additives
  • Manufactured by melting in electric furnace.
  • Stable physical properties.
  • Good resistance to fire (m.p. 1460 ℃ )
  • Excellent strength & low permanent linear change.
  • Widely used for production of refractory castable & insulating castable.
 

 - Cement Properties

Properties

Unit.

  Specification 

Typical Range

Min

Max

Chemical Composition

CaO

%

34

38

35.0~37.0

Al2O3

%

50

 

51.0~54.0

SiO2

%

 3

6

3.5~5.5

TiO2

%

 

4

2.5~3.5

Fe2O3

%

 

2

0.8~1.5

Na2O

%

   

0.02~0.1

K2O

%

   

0.1~0.3

MgO

%

   

0.5~3.5

Fineness

90 ㎛ remains

%

 

 5

1.5~3.5

Blaine

㎠ /g

        4000

 

4500~5500

 
 - Mortar Properties (Cement : Sand : Water = 1 : 2.2 : 0.56)

Properties

Unit.

Specification

Typical Range

Min

Max

Flow

23 ℃

3 minutes

mm

210

 

220~235

30 munutes

mm

210

 

220~240

30 ℃

3 minutes

mm

   

210~230

30 minutes

mm

   

210~230

Setting Properties (23 ℃ )

Vicat test

Initial

hr : min.

   

3:00~4:00

Final

hr : min.

   

5:00~6:00

Exothermic Reaction time

hr : min.

5

7

5:30~6:30

Cured Strength (23 ℃ ×24hr)

Flexural

kgf/ ㎠

50

 

55~65

Compressive

kgf/ ㎠

450

 

520~650

Dired Strength (110 ℃ ×24hr)

Flexural

kgf/ ㎠

 

50~55

Compressive

kgf/ ㎠

 

350~450

 

◎ UAC70N

 - General characteristics

UAC-70N is made in rotary kiln using high purity raw materials and does not contain any additives and α-Al₂O₃.
So it shows good workability and excellent strength, specially, dry & hot strength of UAC-70N is higher than any
other alumina cement because it contains rich cement minerals as CA, CA ₂ . UAC -70N is widely recommended for
high technology refractories such as low cement castable and ultra low cement castable
 
(The characteristics of UAC -70N)
  • Consistant properties
  • UAC -70N does not contain any additives.
  • It gives a full flexibility in application needs without potential mismatches.
  • High strength and long workable time.
 
  - Cement Properties

Properties

Unit.

Specification

Typical Range

Min

  Max

Chemical Composition

CaO

%

 26

29

27.5~28.5

Al2O3

%

 69

 

70~71

SiO2

%

 

0.5

0.1~0.3

TiO2

%

     

Fe2O3

%

 

0.5

0.05~0.1

Na2O

%

   

0.1~0.2

MgO

%

 

0.6

0.1~0.4

Fineness

Blaine

㎠ /g

4000

 

4800~5400

 
  - Mortar Properties (Cement : Sand : Water = 1 : 2.2 : 0.56)

Properties

Unit.

Specification

Typical Range

Min

Max

Flow

 20 ℃

3 minutes

mm

210

 

230~250

30 munutes

mm

210

 

235~255

60 munutes

mm

   

      220~250

30 ℃

3 minutes

mm

   

220~240

30 minutes

mm

   

220~240

Setting Properties (23 ℃ )

Vicat test

Initial

hr : min

   

4:30~5:30

Final

hr : min

   

5:30~7:30

* Exothermic Reaction time

hr : min

5

11

7:00~8:30

Cured Strength (23 ℃ ×24hr)

Flexural

kgf/ ㎠

40

 

50~65

Compressive

kgf/ ㎠

300

 

400~550

Dired Strength (110 ℃ ×24hr)

Flexural

kgf/ ㎠

   

60~80

Compressive

kgf/ ㎠

   

500~600

 

◎ UAC70S

 - General characteristics

UAC - 70S is a specially formulated calcium aluminate cement containing approximately 70% alumina. It is designed to provide consistent physical properties, excellent flow characteristic and long workable time in hot temperature.It does not contain any additives, so it is suitable for low cement castable & ultra low cement castable.

 

(The characteristics of UAC -70S)

  • Stable workable time in hot atmosphere.
  • Suitable for low cement castable using a phosphate additives.
  • High strength and long workable time.
 
 - Cement Properties

Properties

Unit.

Specification

Typical Range

Min

Max

Chemical Composition

CaO

%

26

 28

26.5~27.5

Al2O3

%

 71

 

72~73

SiO2

%

 

 0.5

0.1~0.3

TiO2

%

     

Fe2O3

%

 

 0.5

0.05~0.1

Na2O

%

   

0.1~0.2

MgO

%

 

0.6

0.1~0.42

Fineness

Blaine

㎠ /g

4000

 

4300~4500

 
 - Mortar Properties (Cement : Sand : Water = 1 : 2.2 : 0.56)

Properties

Unit.

Specification

Typical Range

Min

Max

Flow

20 ℃

3 minutes

mm

210

 

230~250

30 munutes

mm

210

 

230~250

60 munutes

mm

   

220~240

30 ℃

3 minutes

mm

   

220~240

30 minutes

mm

   

220~240

Setting Properties (23 ℃ )

Vicat test

Initial

hr : min

   

3:30~4:30

Final

hr : min

   

4:00~5:00

* Exothermic Reaction time

hr : min

4

9

6:00~7:30

Cured Strength (23 ℃ ×24hr)

Flexural

kgf/ ㎠

40

 

45~55

Compressive

kgf/ ㎠

300

 

350~400

Dired Strength (110 ℃ ×24hr)

Flexural

kgf/ ㎠

   

60~70

Compressive

kgf/ ㎠

   

450~550

 * Exothermic Reaction time is tested by recording the exothermic heat development during cement hydration.
 The time when the mix has reached its reached its maximum temperature corresponds to the Vicat Final setting time.

 

◎ UAC80N

 - General characteristics

UAC - 80N is made in rotary kiln using its main ingredient, high purity materials. The whole production process is fully
automated using a state-of-the-art computer system.All products go through quality control procedure in which they are analyzed on the spot by high procisionanalyzing equipment and treated accordingly.Union Alumina Cement 80N
has highest content of Al₂O₃and a high purity product with minimum impurities such as SiO₂and Fe₂O₃.
It is used for castable high temperature (1800 ℃ ) and material for castable which requires durability and resistance to heat and impact.

 

(The characteristics of UAC -80N)

  • Longer workable Time and Good Workability.
  • Stable Physical Properties.
  • Excellent Explosive Spalling Resistance.
  • High Hot Strength.
 

 - Cement Properties

Properties

Unit.

Specification

Typical Range

Min

Max

Chemical Composition

CaO

%

16

 19

17.0~18.5

Al2O3

%

 78

 

79~81

SiO2

%

 

 0.4

0.1~0.3

TiO2

%

     

Fe2O3

%

 

0.3

0.02~0.1

Na2O

%

   

0.2~0.4

MgO

%

   

0.1~0.4

Fineness

38 ㎛ remains

%

15

25

18~22

Blaine

㎠ /g

 

8300~8700

* Fused Alumina 5~3m/m 16% 220F 7%   3~1m/m 30% 325F 14% 1~0m/m 13%  
 
 - Castable Properties (Cement: Fused Alumina : Water = 1:4.0 : 0.45)

Properties

Unit.

Specification

Typical Range

Min

Max

Flow

23 ℃

3 minutes

mm

140

 

155~170

30 munutes

mm

140

 

155~170

Setting Properties (23 ℃ )

Exothermic Reaction time

hr : min

5

 9

6~8

Cured Strength (23 ℃ ×24hr)

Flexural

kgf/ ㎠

30

 

40~60

Compressive

kgf/ ㎠

160

 

200~230

Dired Strength (110 ℃ ×24hr)

Flexural

kgf/ ㎠

 

100~120

Compressive

kgf/ ㎠

 

700~800

Packaging  : 25kg and / or 1MT Jumbo Bag available
 
Origin : Korea