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Date: 2008-2009
Project Description:
Basic Parameters of the Ingot Casting Facility:
• Nominal annual production 50.000 MT
• Ingot mass 3, 15 or 40 MT
• Mass of the molten steel up to110 MT
• Workshop length 48 m
• Workshop width 24 m
• Workshop high 24,5 m
Designing and building of the Ingot Casting Area Facility
in the area of the Steel Shop Department, as extension
to the existing Converter Steel Shop was initiated by
thefollowing:
• Required modernization of the facility due
to the
fact that existing 15 MT electrical furnace facility
(in the area of this facility is located current Ingot
casting area) is over 70 years old.
• Requirements for Ingot Casting Area facility
capacity incensement and usage of 40 MT molds
instead 15 MT moulds that are currently in use.
Equipment and Subsystems
• Ingot Casting Area Building, length 48 m and
width
24 m
• Control Building: Control and MCC room, locker
rooms
• Vacuuming System – Mechanical water ring
pump
and 3 steps of steam ejectors
• Vacuum Tank and Cover
• Cover Transfer Car
• OH crane, capacity 70 MT
• Monorail, 5 MT
• Automatic ingot tongs
• Air mail
• Pipelines for all fluids with entire armature
• Power supply
• Control and regulation system
• Fire detection and protection system
Description of the ingot production process
Production of ingots is consisted by 2 main technological
processes:
1. Vacuum Degazation Process – Hidrogen Removal,
and
2. Ingot Casting
Vacuum Degazation Process The first and most obvious
application of vacuum to extraction metallurgy is to
the removal of dissolved gases like hydrogen from refined
steel. This is carried out by subjecting a ladle of
the metal to low pressure within a vacuum tank which
is hermetically sealed and connected to vacuum pumping
system. During Degazation, pressure in the vacuum tank
should be below 1 mbar. Vacuum is forcing dissolved
gases out of the melt. This procedure can be used in
production of low carbon, high strength, micro alloyed,
stainless and other classes of steel.
The removal of gasses can be improved by introducing
an inert gas such as argon into the metal melt. Argon
is being injected through a porous plug in the ladle
bottom. The melt starts to boil when certain vacuum
is achieved in the vacuum tank.
Starting data:
Quantity of the liquid steel: 95 – 110 MT,
H2 Content before degazation: up to 7,5 ppm
Steel temperature: 1645 – 1650 0C,
Degazation data:
Pressure into vacuum tank: = 1 mbar
Ar flow: 400 – 600 N l/min
Time of Ar purging: up to 20 minutes.
Final data:
H2 Content after degazation: 1,4 to 1,7 ppm (below 2
ppm)
Steel temperature: 1570 - 1580 0C,
Ingot Casting Ingot casting is final metallurgical
operation in steel metallurgy. Cast ingot has to have
high strength, minimal degree of segregations, adequate
chemical composition and well surface quality. Number
of reactions is possible after pouring the melt in the
mould (reaction with mould dressing, slag or atmosphere).
Temperature is decreasing in cast steel (cooling of
the melt) with simultaneously phase change (liquid to
solid), lowering the solubility of gasses, etc. Dragging
the casting powder from the top surface caused by turbulent
flow of the melt in the mould, or mould inner refractory
dressing could decrease purity of the steel. The purpose
of ingot casting is producing of geometrically simple
forms using vertical stable ingot moulds. Solidified
steel semi product is called ingot. Ingots are designed
for further processing by plastic deformation (rolling
or forging). Casting trolley is used for transporting
of casting ladle with liquid steel from the vacuum tank
to casting pit. Casting pit is designed for the following
size of ingots:
3 MT – in set of 5 pcs,
15 MT –in configuration of 3 x (2 x15 MT),
40 MT – in configuration of 2 x (2 x 40 MT, or
in some combination of previously configuration.
Scope of Work:
»Basic and detail design of Ingot Casting Plant
» Manufacturing of equipment
»QA During Manufacturing
»Erection and Connections
»Cold & Hot Testing
» Start-Up
» Training of Production and Maintenance personnel
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Ingot Casting Plant 
