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PROJECT REPORT

FUNCTIONING OF LADLE TURRET

IN

CONTINUOUS CASTING SHOP, SMS II

A Project report submitted in partial fulfillment of the Requirements for

Management Development Program for MT (Tech)

Prepared By

BRAHMANANDA REDDY SAGILI

MT (TECH)

EMP. NO. : 123140, SMS II (CCD)

Under the esteemed Guidance of

SRI K.V. SIVAPRASAD

AGM (CCD-MECH), SMS II

TRAINING AND DEVELOPMENT CENTRE

VISAKHAPATNAM STEEL PLANT

VISAKHAPATNAM.



2

CERTIFICATE

This is to certify that the Project titled “FUNCTIONING OF LADLE

TURRET IN CONTINUOUS CASTING SHOP SMS II” is fulfillment as a part of training

program imparted by RINL/VSP during the year 2013 is a bonafide work carried on by

BRAHMANANDA REDDY SAGILI, Emp.No.123140, MANAGEMENT TRAINEE

(TECHNICAL), SMS-II under my guidance.

VISAKHAPATNAM

Date:

K.V. SIVAPRASAD

AGM

CCD (MECH)

SMS II



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ACKNOWLEDGEMENT

I acknowledge my profound gratitude & thanks to Sri K.V.SIVAPRASAD,

AGM, CCD (MECHANICAL) for advising me to take up this project work on

“FUCTIONING OF LADLE TURRET IN CONTINUOUS CASTING SHOP SMS II”

under his able guidance & support extended to prepare this project report.

I express my deep sense of gratitude to Sri K.V.SIVAPRASAD, AGM

(CCD -MECHANICAL) for his valuable advice and help extended to me in

preparing this project in spite of his busy office schedule.

BRAHMANANDA REDDY SAGILIMT (T) Emp.No.123140



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INDEX

1.

INTRODUCTION TO CCD, SMS II 5 - 8

2.

LADLE TURRET FUNCTIONS 9 - 11

3.

LADLE TURRET TECHNICAL SPECIFICATIONS 12 – 13

4. SYSTEM EQUIPMENTS 13 - 16

5.

LADLE TURRET DRIVE UNIT 17 - 18

6. LADLE TURRET BEARING FUNCTIONING 19

7.

ARM LIFTING CYLINDER 20 - 21

8. TURRET LOCKING CYLINDER 22

9.

ROTARY JOINT 23 - 24

10.

EMERGENCY ROTATION 24 - 25

11.

LADLE COVER MANIPULATOR 26

12.

LADLE TURRET MAJOR ALARM SIGNALS 26 - 27

13.

DIFFERENCES BETWEEN LADLE TURRET OF SMS 2 & SMS 1 28



[5]

1. INTRODUCTION TO CONTINUOUS CASTING MACHINE, SMS II

The expansion phase of Vizag Steel from present 3.3 MT to 6.3 MT boasts a new SMS

unit namely SMS II which consists of 3 Continuous Casting machines against the 6machines of the present production phase all of which are still yet to be commissioned soon.

The 3 machines are supplied and erected by Danieli Centromet, Italy. A photo of one of the

casting machines namely CCM#1 is shown below in fig: 1.1.The casting machines in the

expansion phase has 6 strands instead of the available 4 strands in SMS I. The machine radius

is 10 m instead of the 12 m radius of all the machines in SMS I. The products formed are

billets and rounds in SMS II cater instead of the blooms formed in SMS I caster. CCM#1

produces billets of size 150X150 and 200X200 and rounds of 220,280 and 350 mm

diameters. Similarly CCM#2 and 3 produces only billets of sizes 150X150 and 200X200.

Fig : 1.1: View of the Casting machine (CCM#1) while casting



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Given below are the main characteristic of the Casting Machine in SMS II:

Machine type 3BLC1006

Number of strands 6

Machine radius 10 m

Unbending radii 19 m

Strand distance 1,5mm

Outfit sections Squares of 150x150 and 200x200 and rounds of

Ф220,Ф280 and Ф350

Ladle capacity 160 t max -150 t nominal

Ladle support Butterfly fork type, 2 independent lifting and lowering

system,

Load capacity 250 t

Ladle cover manipulator Hydraulic type

Ladle shroud manipulator Pneumatic type

Tap to tap time 50 min average

Tundish car Cantilever with electro-mechanical drive

Tundish capacity 35 t

Mould tube Multitaper, Curved 780 mm long for Ф 220- Ф 280- 350mm

Multitaper, Curved 1000 mm long for 150x150 mm

Mould lubrication Oil and Powder for 150x150 mm

Powder for round sections(Closed Casting)

Tundish to mould flow control Slide gates for rounds

Slide gates and FNC for 150x150

mm



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Mould level control Radioactive

Electromagnetic stirrer Mould EMS external + Final EMS

Oscillating unit Hydraulic actuated

Dummy bar rigid

Containment for each strand 2 rows of foot rolls for round sections

3 rows of foot rolls for 150x150 mm and 200x200 mm

Secondary cooling system First zone (foot rollers): water cooling

Zone 2 mist coolingZone 3 mist cooling

Zone 4 mist cooling

Straightening Modular type (5 module per strand) with shaped rolls

Max metallurgical length 24.4 m approx

Withdrawal speed range 0.25-4 m/min

Billet cutting Oxy cutting

Torch Cutting length 6-12 m for billets, 4-6.5mfor rounds

Discharge system Liftable transfer system, turnover cooling bed



[8]

2. LADLE TURRET FUNCTIONS

Turret is designed to support the steel ladles and rotate them from the charging side, where

the overhead crane delivers the ladle, to the casting position, just in above of the tundish.

Turret is fixed with one rigid ladle support arm, designed in a “H” shape to accept ladles

delivered perpendicular to the caster axis. The arm rotates on a central bearing. Compressed

air, inert gas and electrical signals are conveyed to the arm through a rotary joint installed in

the supporting base, this allows a continuous revolving of the turret (360°).Turret is equipped

with a sturdy base frame, rigidity of the structure allows for negligible deflection of the arm.

Main components of the Ladle Turret are:

a) Supporting Structure, made of welded steel sections, anchored via flange and

anchoring bolts to a reinforced concrete base.

b) Central steel body, designed to accommodate the thrust bearing and the arm-driving unit. Bearing, three – row cylindrical roller type.

c) Rotating joint to distribute all utilities.

d) “H” shape ladle arm, made of welded steel sections and dimensioned to handle

ladle of the rated capacity. At each end of the arm, a supporting fork with two

ladle holding saddles is installed. Each saddle is lift able via a hydraulic cylinder.

A total of four cylinders are supplied. Saddles are suitable for installation of

weighing cells.

e) AC motor driving unit equipped with inverter, encoder and brake. The variable

speed motor guarantees a progressive acceleration and deceleration without any

jerking of the arm motion. Motor is coupled with a gearbox and motion is

transmitted through a rack and pinion Gear system.

f) Pneumatic motor for emergency drive, installed on the opposite side of the main

motor and connected through the same shaft of the gearbox, operation is switched

automatically in case of power failure.

g) Dedicated accumulators provide the necessary Instrument air.

h) Weighing system located in the turret arms in order to continuously record the

weight of the ladle before or during casting.



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LADLE TURRET

Fig: LADLE TURRET DRAWING



[10]

Fig : LADLE TURRET AT CCD SMS-II



[11]

3. LADLE TURRET TECHNICAL SPECIFICATIONS:

Main Characteristics:

• Shape One Arm : “H“ Type

• Radius : 5500 mm

• Full Ladle weight max. : 250 Ton

• Liquid Steel weight. : 150/160 Ton

• Rotation Motor (AC type) : 1500 rpm

• Turret Rotation Speed : 1.0 rpm

• Direction of Rotation : Bi – Directional

• Rotation Motor (emergency) : Pneumatic Motor

• Turret Rotation Emergency Speed : 0.5 rpm

Weighing cells

• Number 4+4

• Type Compression

• Total load capacity 250 Ton

General data

• Type: “H” type

• Ladle rotation radius: 5500 mm

Dimensions

• Length with two ladle 15076 mm

• Length without ladles 12684 mm

• Width 5530 mm

• Height 10142 mm• weight 188100 kg

Arm locking cylinder

• Quantity 1

• Type hydraulic

• bore 100 mm

• Rod 70 mm

• stroke 160 mm

• feeding from hydraulic central unit



[12]

Benefits:

Best utilization of the bridge crane, which is not engaged in supporting the ladle during

casting.

The shortening of the time necessary to the ladle change during the castings in sequence

TRAINING CENTER

Description:

1) First machine of the continuous casting machine;

2) Fixed basement with a housing for the base bearing for the arms rotation:

the basement is fixed to the foundation

3) Supporting saddle provided with appropriate guiding and reference devices to allow

an easy charging of the ladle from the front;

4) Drive unit composed of a varying speed motor, a planetary gear box and pinion and

equipped with pneumatic motor, mounted directly on the transmission, which ensures

the emergency rotation in case of electric motor failure;

5) a rotating coupling allows the feeding of the mobile parts on the turret;

6) The position of the turret is controlled by an installed encoder and limit switch.

TRAINING CENTER

4. COMPOSITION AND DESCRIPTION

The turret is a "normal twin-fork turret": it is composed of a double fork rotating

arm supported by a circular structure made of welded carpentry, properly Stiffened and

longitudinally ribbed. The basement upper part is realized so that it is possible to have a

housing for the thrust bearing for the arm rotation; the inferior part is fixed by a basement to

the foundations, by means of anchoring bolts. Each arm consist of a central unit and a

supporting saddle provided with appropriate guiding and reference devices to allow an easy

charging of the ladle from the front.

The arms are hinged to a central structure of welded steel supported by the thrust

bearing for the simultaneous rotation of the arms. Each arm is lifted by an independent

hydraulic cylinder to allow submerged casting (insertion of the nozzle under the ladle) and

facilitate all the operations for opening the ladle side gate in case of problems or clogging

The inside of the circular structure encloses all the pipings of the service plants to the turret

and it is accessible for inspections and maintenance.

TRAI



[13]

The arm rotation takes place by means of a driving unit composed of a varying

speed motor, a planetary gear box and a pinion, a pneumatic disc brake with a cylinder and an

emergency pneumatic motor (main motor broken or missing of feeding tension).The arm

rotation speed and its stopping in perfect position are guaranteed by encoders and limit

switches.

The turret is dimensioned for supporting ladles with the following:

1 full ladle and an empty ladle;

2 full ladles;

1 full ladle and an empty arm (shock factor = 2).

In every condition, apart from the charge, the turret ensures the correct arrest during the

ladle/s rotation, respectively in the positions of casting, ladle drawing or emergency. By a

bridge crane the ladle with the liquid steel is drawn from the furnace zone and deposited on a

fork of the turret arm .he arm rotates of 180°, it carries the ladle in a proper position for

casting the steel into the tundish (distribution equipment), already positioned in

correspondence with the lines.

The interlocks to enable the rotation of turret are:

General emergency stop not active

Emergency rotation cycle resetBrake is open (brake release valve is energized and signal from limit switch)

The rotation acceleration and deceleration avoids ladle spills, the rotation cycle is:

Fig. Ladle turret speed control

At the end of the casting the empty ladle shall be collected again by the bridge crane

in the same position in which it had been previously delivered. The turret, in case of casting

interruption, because of accident or various unforecastble events, operates as an emergency

device carrying the ladle to discharge the residual metal, still present, into the emergency

ladle.

100

045 120 180 Pos [°deg]

Speed[%]



[14]

On each fork of the turret there is installed a system for the weighing of the ladle,

composed of:

4 (two + two) load cells;

Weight transmitters;

One large display installed on the casting floor in the operative area.

A rotating coupling (connected on the turret shaft) allows the feeding of the mobile parts on

the turret such as bearing, gears, pin-joints with the following fluids:

Grease.

Compressed air.

Inert gas

TRAINING CENTER

1. Compressed air (IA) system

The system feeds the pneumatic devices for the emergency rotation and the turret braking.

If necessary, the air is filtered and lubricated for every group of appliances.

The system consists of the following appliances:

Loading boxes and cells cooling;

Ladle turret brake (disk brake);

Emergency rotation (pneumatic motor);

Emergency device for slide gates.

The system is provided with solenoid valves actuating the devices listed above, flexible and

rigid pipes according to supply and gate valves on the machine. The compressed air is

supplied by the steel plant and must be of standard industrial quality.

2. Inert gas system (argon)

The plant is designed to feed the liquid steel bath of both ladles for the stirring.

The plant includes all the pipes in the turret, including hoses, pipe fittings, gas rotating jointand quick clutches between arm and ladle.

3. Ladle rotating turret arms maneuvering hydraulic system

The central unit of this plant enables to control and actuate all the devices of the system.

In particular it services the following appliances:

Ladle lifting/lowering on the arm 1;

Ladle lifting/lowering on the arm 2;

TRAINING CENTE



[15]

4. Grease centralized lubrication system

In the lift able ladle turning turret there are one centralized systems of grease it

Supplies to the following points.

Thrust bearing and pinion: 42

Arm pins: 12

Jib crane: 4

5. Ladle turret weighing system

On every turret arm, a weighing system is applied for the ladle weight measurement.

6. Electric systems

The turret's electric system includes the necessary equipment for the correct functioning of an

electric component: in this particular case the electric motor for rotating the turret, electric

collector for the weighing system, the solenoid valve for the pneumatic system and all the

electric devices on the control panel.



[16]

5. LADLE TURRET DRIVE UNIT :

Electric motor

• Quantity 1

• power 37 kW; 1500 Rpm; 5÷50 Hz

• Direction of rotation bi - directional

• Type of brake disc brake with thruster

The drive system is equipped with an electric motor coupled to a pneumatic motorthrough a common shaft. Pneumatic piston motor is used for emergency rotation in low

rotation speed. The electric drive system is hold by using a pneumatic brake. This pneumatic

brake system is operated by instrument air which is supplied at a pressure of 6bar for holding

the brake.

The connection with the bevel gear is guaranteed by means of a “key connection”.

The device requires oil for seal lubrication and seal check for oil leakage. The connection

with the bevel gear is guaranteed by means of a “key connection”. The purpose of the bevel

gear is to drive the motion from one axis to the orthogonal by means of an input shaft from



[17]

the electric motor which thanks to a spiral bevel gear 1:1, works on the output shaft double

projection (one towards the pneumatic motor and the other one towards the planetary gear

box).

Gearbox

• Quantity 1

• Type planetary with angular gear

• Ratio 1:117

Pneumatic motor

• Quantity 1 (horizontal position)

• Direction of rotation bi – directional

Planetary gear box: In the fixed ring gear planetary reduction gear unit, motion is

transmitted by the sun gear to the planetary gears which is enveloping the ring gear. It rotates

in the same direction as the input motion of the sun gear - entrain the planet carrier connected

to the output.

Every stage is formed by:

1) RING GEAR: (reaction element) internal tooth in contact with the planetary gears

(output motion element). There are three gears for each stage. Every planetary gear

has an associated axis and each planetary gear and axis has a group of bearings. Its

function is to support the loads acting on the planetary gears and transmit them to the

planetary gear axis.

2) SUN GEAR: the planetary gears are in contact with the sun gear (input motion

element).



[18]

3) PLANETARY GEARS: the planetary gear axis is an integral part of the planetary

carrier (output motion) and has the function to bring and connect the planetary gears

by means of their axis.

6. BEARING FOR ROTATION

The rotation of the turret is achieved by a big gear which is in contact with pinion

which is present at the end of the electric drive unit output shaft. The gear is mounted on a

three row cylindrical roller bearing. The three row roller bearing is as shown in figure. It

contains two rows of horizontal rollers and one row of vertical rollers. The two horizontal

rollers are present at top and bottom and vertical rollers are in the middle.

The horizontal rollers are provided to with stand the axial load of the system and the

radial load is with stand by vertical rollers of the bearing. Bearing is lubricated by centralized

grease system with two lines. The wear and tear of the axial rollers is measured by measuring

the distance between the two fixed points at eight different positions on the turret. The wear



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and tear of vertical rollers is measured by measuring the readings of dial gauge at different

positions when the turret is moving.

7. ARM LIFTING CYLINDER

• Quantity 1on each arm

• Type hydraulic

• bore 600 mm

• R od 350 mm

• stroke 670 mm

• feeding from hydraulic central unit CH2.

When the arm is lifting the hydraulic oil at high pressure will enter into the cylinder

through P line. When the hydraulic oil enters into the cylinder it will exert pressure on the

piston, so that the piston rod moves outside. The end of the piston rod is connected with the

end of the arm. The input stroke of the piston rod is 670 mm, but due to the orientation of the

arm will get a stroke of 800mm. While lowering arm the hydraulic oil is returned through T

line. When the pressure removed on the piston, piston will reach its initial position.



[20]

Arm lifting cylinder has a four bar chain mechanism to lift and lower the arm. It consists of a

cylinder and 3 links. The top end of the cylinder is fixed and the end of the rod is fixed to the

arm link1. Link 2 is for supporting it is connected to arm from the frame of turret. Link 3 will

joins the link 1 and 2. When the cylinder opens due to the relative motion transfer from

cylinder rod to the link 1 arm will be lifted. The mechanism and arrangement of links is as

shown in figure.

The load distribution of the turret will be in the following way.

When a full ladle is kept on turret the load is acting vertically down words at the end of the

link 1 and it is transferred to end of the rod. The load is balanced by the high pressure

hydraulic oil which is applying pressure on the top of the rod. Some of the load is carried by

the frame. From the frame the load is transmitted to the foundation. Some amount of load is

acting on the gear and bearing system.



[21]

8. ARM LOCKING CYLINDER:

• Quantity 1

• Type hydraulic

• bore 100 mm

• Rod 70 mm • stroke 160 mm

• feeding from hydraulic central unit

The locking cylinder is used to arrest the movement of ladle turret when it is in casting

position. The locking cylinder is fixed on the stationary part of the turret. It is operated by the

central hydraulic Unit, the pressure of the system is 200 bar. When the locking command

given the hydraulic oil enters into the locking cylinder and the piston rod pushed to outside, it

will enters into the groove which is constructed on movable part of the turret, near to the

bearing. When piston rod enters into the groove it will arrest the movement of the turret.



[22]

9. THE ROTARY JOINT

The bottom part of the rotary joint is stationary and the top part is movable. The bottom part

contains hydraulic swivels for the supply of hydraulic oil, grease and utility lines.

Hydraulic swivels are composed of:

INTERNAL BODY: It is general built in carbon chromed steel on the working

surface on which the seals slide.

EXTERNAL BODY: It is built of Fe520b.



[23]

LOCKING ELEMENT: It is constituted of a tempered bottom plate or simply by an

anchor pin clip.

The rotary joint contains 18 numbers of swivels for different purposes.

4 swivels for ladle slide gate opening and closing of both the arms.

2 swivels for grease system.

4 swivels for lowering and lifting of arm 1 and arm 2.

1 swivel for common leak line of arm 1, arm 2.

3 swivels for jib crane pressure, tank and leak lines.

2 swivels for instrument air for arm 1 and arm 2.

2 swivels for argon of arm 1 and arm 2.

10. EMERGENCY ROTATION

The emergency rotation is provided to remove the ladle at casting position,sending it

to the emergency position where an empty ladle can collect the steel spilled from the ladle on

the turret arm.

The cycle performed is as clockwise normal rotation.



[24]

The interlocks to enable the emergency rotation are:

Brake is open (brake release valve is energized and signal from limit switch)

R OTATION WITH THE PNEUMATIC DRIVE

It is provided with an emergency rotation backup, which can be used in case of failure

of the electrical rotating Unit. A pneumatic motor which is manually controlled achieves the

rotation. Pneumatic piston motor is used for emergency rotation in low rotation speed. The

pneumatic piston motor is connected to the common shaft of electric motor. The pneumatic

piston motor consists of 5 pistons arranged in equal angles. To run the pneumatic drive IA

(instrument air) is used. The pressure of the IA to operate the pneumatic motor is 6 Bar.

Pneumatic motor can rotate in both clockwise and anti-clockwise direction. When

there is a power failure pneumatic drive is operated manually. The pneumatic drive rotates in

both the directions. When power supply fails, the brake of the drive unit will automatically

get closed. To open the brake and to rotate the turret from casting position to home position

(non-casting position), the pneumatic drive is used. The instrument air circuit for the turret

emergency rotation is as shown in figure.



[25]

11. LADLE COVER MANIPULATOR

The ladle cover manipulator also called as jib crane. It is as shown in figure. The function of

the ladle cover manipulator is to reduce the heat loss from liquid metal to the atmosphere so

that the solidification of liquid steel before casting is avoided. It can rotate about 2700 from

its centre. It contains a lid type structure at its end whose diameter is equal to the diameter of

the ladle top portion. The bottom portion of the jib crane is covered by high heat resistant and

thermal insulating material so that it can with stand to high temperature and prevents heat

loss from liquid steel. It is operated by a hydraulic cylinder for lowering and lifting as shown

in below figure. The required rotation is achieved by a hydraulic motor.

Fig: Ladle cover manipulator lifting cylinder



[26]

12. LADLE TURRET MAJOR ALARM SIGNALS TO START CASTING:

1) Ladle turret emergency stop from LCS 1.

2) Drive not ready signal

3) Drive ready consent lost due to encoder faulty signal

4) Brake open time out

5) Compressed air pressure low-low indication

6) Ladle arm 1 lift limit switch

7) Ladle arm 2 lift limit switch

8) Ladle arm 1 lift solenoid time out signal

9) Ladle arm 2 lift solenoid time out signal

10) Insertion pin un lock limit switch faulty signal

11) Insertion pin lower solenoid de energize time out signal

12) Insertion pin upper limit switch continuous actuation signal

13) Power failure

14) Min-min tank oil level

15) Min-min delivery pressure

16) Oil high-high temperature

17) Temperature sensor fault18) Level sensor fault

19) Pressure sensor fault

20) Pump suction valve closed

21) Line pressure ready time out

22) Pump 1 tripped

23) Pump 1 run confirm time-out

24) Pump 2 tripped

25) Pump 2 run confirm time out

26) Pump 3 tripped

27) Pump 3 run confirm time out

28) Hydraulic unit emergency stop

29) Recirculation pump1 tripped

30) Recirculation pump1 run confirm time out


32) Recirculation pump2 run confirm time out




34) Recirculation pump3 run confirm time out.

13. DIFFERENCES BETWEEN LADLE TURRET OF SMS 2 & SMS 1:

SMS 2 SMS 1

1. Double arm butterfly type ladle turret

operated by two cylinders.

2. Each arm is operated individually for

lowering and lifting by the respective

cylinders.

3. Effective pneumatic system is provided foremergency rotation.

4. Locking cylinder is provided to arrest the

movement in casting position.

5. 3-Row cylindrical roller bearing is

provided for effective rotation of the turret.

6. Jib crane is provided for closing the ladle

while casting.

7. A rotary joint is provided for transferring

hydraulics and utilities to the turret.

1. Normal H type double arm turret, operated

by a single cylinder kept at the centre.

2. Individual arm operation is not possible,

both arms lifted or lowered at once

.

3. Pneumatic system is not provided foremergency rotation.

4. Locking cylinder is not provided to arrest

rotation in casting position.

5. Thrust and radial cylindrical roller

bearings are provided for turret rotation.

6. No jib crane.

7. Rotary joint is not provided.

Advantages of Ladle turret in SMS-2 over SMS-1:

1. Slag detection system is provided to detect the level of molten metal.

2. Each arm can operate individually.

3. Jib crane is provided for covering the ladle while casting to minimize the temperature drop.

4. Effective pneumatic system is provided for emergency rotation.

5. Locking cylinder is provided to arrest the movement in casting position.

ladle turret

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