• Homogenizes the melt
• Removes contaminants
• Regulates temperature

Plug & Block

Any Size and composition meet to your need

1. Durastir ND Plug (Non Directional)
2. Durastir DP Plug (Directional Plug)
3. We are also able to make plugs and blocks any size or composition to meet your needs.  
4. We are also an agency for Special Shapes Refractory Co. which produces a plug called the stirpro

• Quantity of gas
• Pressure of gas
• Purging time
• Steel Quality (Viscosity)
• Steel Temperature
• Purging plug maintenance (Purification with O₂)
• Bottom Lining Life
• Purging Plug Type
• Ladle Circulation (Thermal Shocks)
• Infiltrations

            Final Alloying

     Desulfurization

           Oxygen / Hydrogen removal

    Reheating

1. DEOXIDIZING CONDITIONS
2. Si-Mn DEOXIDATION INSIDE FURNACE: Si0.5 –0.8 % Mn1.2 –1.7 %
3. AL DEOXIDATION (AL 1.1 lbs/ton ADDED INTO FURNACE)
4. BASICITY OF SLAG 1.4-2.6
5. ARGON PRESSURE 42.6 PSI
6. ARGON FLOW 5SCFM
7. INJECTION TIME 6 MIN. max

1. TYPE OF STEEL .35 C, .8MN
2. 25 T HEAT SIZE
3. TOTAL BUBBLING TIME –9 MINUTES
4. GAS FLOW 75 SCFM
5. GAS PRESSURE 55 PSI

1. ABOVE GRAPH FOR 150 TON LADLE
2. INJECTION TIME 12 MINUTES
3. GAS FLOW 9 SCFM
4. GAS PRESSURE 49.7 PSI

• WITH BUBBLING TEMPERATURE STRATIFICATION WILL BE 50^OF OR LESS
• WITHOUT BUBBLING TEMPERATURE STRATIFICATION WILL BE 120^OF OR MORE

BEARING QUALITY STEEL

225 TON PER HEAT

TAP TEM. 3000^O*

LADLE TEMP. 2910^O*

FINISH TEMP. 2800^O*

*NO CAL-SIL INJECTION

SULPHUR AT START 0.032

SULFUR AT FINISH 0.011

USED SYNTHETIC TOP SLAG

80% BURNT LIME

20% FLOURSPAR

25 lbs. TON

Plug location = radius / 2

Measured after refractory lining is in place

1. Do not apply gas pressure to the plug exceeding 150psi.

2. Establish flow meter and back pressure reference points for your particular operation.

3. Perform a natural gas check to determine the operational readiness of the plug immediately after casting. See attached recommended procedure.

4. Between heats and after degassing, look for the safety shape change feature which will indicate when it is time for plug replacement.

5. In conjunction with the safety shape change feature, the life of the plug should be determined by accurately recording the number of stirring minutes on that particular plug. (Determining the life of a plug by the number of heats could be misleading and is not recommended.)

6. Best stirring practices do not break the slag cover. If a violent stirring practice is followed, as sometimes with desulfurizing, temperature control or vacuum degassing, follow-up with a soft stir without breaking the slag cover in order to remove impurities.

7. The major causes resulting in no stirs are:

   • Penetration

   • Skulls

   • Failure to pretest plug

   • Failure of gas supplying syste