MD DILSHAD KHAN

Location ;- JSW Vijaynagar Work

Company:- VESUVIUS INDIA LIMITED

Site :- SMS # 4 Tundish Preparetion work

Job designation:- Supervisor

Experience - 2.6 Year

Date of joining :- 21/11/2024

Date of Not leave:- Continue

Location:- JSW Vijaynagar Work

Company:- Vesuvius India limited

Site :- BLAST FURNACE #05

Job designation:- Supervisor

Experience - 1 Year

Date:- 10/01/2024

Date of Leaving :- 07/11/2024

Company name:- TATA Taco prestolite private limited

Job designation:- Q.C Assistant

Date:- 18/01/2023

Date of Leaving :- 17/12/2023

JSW Steel Vijayanagar Works, Steel Melting Shop #4 (SMS #4) is a state-of-the-art facility

featuring advanced technology, including high-capacity RH vacuum degassers and slab casters. The Tundish Preparation Work is a critical maintenance and operational cycle that ensures the liquid steel remains clean and flows at a controlled rate into the molds.

Below is the standard workflow for Tundish preparation typical for a high-efficiency unit like SMS

#4

1. Cooling and Deskulling

After a casting sequence is completed, the "used" tundish is moved to the preparation bay.

● Cooling: The tundish is placed on a cooling stand. Forced air or water mist may be used

to bring the temperature down safely.

● Deskulling: The "skull" (solidified residual steel and slag) is removed. At SMS #4, this is

often done using specialized tilting stands or hydraulic machines to ensure the permanent

refractory lining isn't damaged.

2. Refractory Lining (Working Lining)

The tundish has a permanent lining (bricks) and a Working Lining that is replaced frequently.

● Spraying/Trowelling: A magnesium-based (MgO) spray mass is applied to the walls and

bottom. This protects the permanent lining and prevents steel from sticking.

● Thickness Check: Typically, walls are maintained at 40\text{}50\text{ mm} and the

bottom at 50\text{}60\text{ mm}.

● Curing: The spray mass is allowed to set (usually 30–60 minutes) to evacuate moisture

and prevent steam explosions when hot metal is poured.

3. Installation of Tundish Furniture

This involves setting up the flow control and protection components:

● Impact Pad: A reinforced block placed at the bottom where the steel stream from the

ladle hits. It reduces turbulence and erosion.

● Dams and Weirs: Internal walls that direct the flow of steel to help "float" inclusions

(impurities) to the surface.

● Nozzles & SEN: The Submerged Entry Nozzle (SEN) is fixed and aligned using jigs.

Precise centering (usually \pm 2\text{ mm}) is required for quality casting.

● Stopper Rods: These control the flow of steel into the mold. They are aligned and teste

1. Tundish Preparation Work

The tundish acts as a buffer between the ladle and the mold. At SMS-4, preparation is a

multi-step refractory and mechanical process:

●Diskulling: Removing the "skull" (solidified steel) from the previous heat. This is usually

done on a tilting stand or using a pusher machine.

●Working Lining (Spraying): Applying a fresh layer of MgO-based refractory spray mass.

This protects the permanent lining and is replaced after every casting sequence.

●Furniture Setting: Installing the dams, weirs, and impact pads that control the flow and

turbulence of the molten steel.

●Nozzle & Stopper Fixing: Precise alignment of the Submerged Entry Nozzles (SEN)

and the Mono-Block Stoppers (MBS) which control the steel flow into the caster.

●Drying & Preheating: The prepared tundish is placed on a heating stand for a specific

cycle (usually 4–6 hours) to remove moisture and bring it to casting temperature.

4. Preheating Cycle

Before moving to the casting car, the tundish must be bone-dry and red-hot.

● Drying: Slow heating to 400^\circ\text{C} to remove chemical water.

● High-Heat Preheating: The temperature is raised to roughly 1000^\circ\text{C} to

1200^\circ\text{C} just before the "heat" (liquid steel) arrives. This prevents "thermal

shock" and keeps the steel from freezing in the nozzles

1. T.C.D. Machine (Tube changing & Device):

The T.C.D. machine is an integrated system designed to apply the refractory "working lining" and then dry it to ensure it is ready for the high-heat preheating stage.

●Coating (Spraying): The machine uses a robotic arm or a specialized nozzle system to spray a magnesium-oxide (MgO) based slurry onto the permanent brick lining of the

tundish.

●Goal: It creates a sacrificial layer that protects the permanent bricks and allows the

"skull" (solidified steel) to be easily removed later.

Drying: Once the spray is applied, the machine (or a connected station) uses

high-velocity burners to remove moisture.

Critical Step: If moisture remains, it can cause "hydrogen pick-up" in the steel or,

worse, a steam explosion when the 1550^\circ\text{C} liquid steel hits the surface.

Efficiency: At SMS #4, these machines reduce human exposure to heat and ensure an

even lining thickness, which is vital for long "sequence" casting (where one tundish stays

in use for many hours).

2. Slide Gate Machine (Tundish Slide Gate System)

The Slide Gate is the mechanical "valve" located at the bottom of the tundish. The Slide Gate

Machine refers to the workstation where these complex mechanical assemblies are serviced,

tested, and fitted.

●Function: It uses two or three refractory plates (usually alumina-carbon or zirconia) that

slide against each other to open, close, or "throttle" the flow of steel into the mold.

●Preparation Work: * Cleaning: Removing steel splashes from the previous heat from the

housing.

○Plate Installation: Using the machine to precisely align the "fixed plate" and the

"sliding plate.

" Even a 1\text{ mm} misalignment can cause a leak.

○Spring Loading: The machine applies high pressure (via heavy-duty springs) to

the plates so that steel cannot leak between them.

○Testing: Before the tundish is sent to the caster, the slide gate is "stroked" (opened

and closed) multiple times using a hydraulic power pack to ensure smooth

movement.