final project

1. 1

PROJECT REPORT
on
Study Of Coil Packaging Line Equipments
at
CRM, TATA STEEL

Submitted by:
Arvind Prajapati
VT20160934

Under the guidance of
Mr. Vijay Narayan Singh

Department of Electrical
and Electronics Engineering

GANDHI INSTITUTE FOR TECHNOLOGY
BHUBANESWAR, ODISHA

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Acknowledgement

The purpose of this industry oriented training was to make us familiar with the
working environment, methods implemented and the equipments used in
completion of any task. So first of all I would want to thank SNTI for accepting our
training applications form so that we got chance to do the internship here.
Then I would like to thank my project guide Mr. Vijay Narayan Singh for guiding me
through my internship and instructing me at every point of time.
The visit to the Coil Packaging Line (CPL) would not have been successful without the
employees such as Mr. Rajesh, Mr. Zubin and others working there who helped me in
understanding the packaging process. Thus I would want to thank them for their
support.

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Certificate

This is to certify that Mr. Arvind Prajapati a student of GANDHI INSTITUTE FOR
TECHNOLOGY, BHUBANESWAR has successfully completed his project entitled:
“STUDY OF CPL EQUIPMENTS IN CRM” under my guidance and supervision at CRM,
TATA STEEL, JAMSHEDPUR.
The duration of the project was from 08/06/2016 to 28/06/2016. During his project
period, he has shown keen interest and sincerity towards the accomplishment of this
project. His approach and conduct were found satisfactory.

CERTIFIED BY:
Mr. Vijay Narayan Singh
Manager (IEM)
CRM, TATA STEEL

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Contents
Sl. No. Topic Page No.
1. Introduction(TATA STEEL) 3
2. Cold Rolling Mill(CRM) 4
3. What is cold rolling? 5
4. Need for cold rolling. 5
5. CRM process flow at TATA STEEL 5
6. Process flow in CRM 6
7. Departments in CRM 6
8. Brief explanation about CRM 7
9. Coil Packaging Line 8-19
a. Coil specifications
b. Description
c. Need for packaging
d. Stations in detail
i. Entry feeding system
ii. Coil packaging Line
iii. Evacuation System
e. Stations in CPL
10.Layout of CPL 20
11.Packing Consumables 21-24
12.Controller used in CPL 24-26
13.The coil master 27
14.Circum-strapping machine 28
15.Eye-strapping machine 29
16.Sensors employed 29-32
17.Conclusion 33

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Introduction
Tata Steel:

Tata Steel, formerly known as TISCO (Tata Iron and Steel Company Limited),
is the world's sixth largest steel company, with an annual crude steel capacity of
31 million tonnes. It is the largest private sector steel company in India in terms
of domestic production. It is based in Jamshedpur, Jharkhand, India. It is part of
Tata Group of companies. Tata Steel is also India's second-largest and second-
most profitable company in private sector. Its main
plant is located in Jamshedpur, Jharkhand. With its
recent acquisitions, the company has become a
multinational with operations in various countries.
Tata Steel was established by Indian Parsi
businessman Jamshetji Nusserwanji Tata in 1907.
TATA STEEL’s four phase modernization program
in the steel works has enabled it to acquire most
modern steel making facilities in the world. Tata Steel commissioned its 1.2
million tonnes capacity Cold Rolling Mill complex in the year 2000. Its fifth

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phase of the Modernization Program leveraged the intellectual capabilities
of its employees to generate sustainable value for the stakeholders.

Cold Rolling Mill

The CRM complex has been commissioned at TATA STEEL works in the year 2000.
The total output of CRM complex consist of 0.8 Mt of cold rolled and annealed
products and 0.4 MTPA of cold rolled and galvanised products. Hence, the total
installed capacity of this unit is 1.2 million tonnes per annum. The range of thickness
and width of these cold rolled products are 0.2 mm to 3.2 mm and 800 mm to
1500mm respectively. The primary input material to the CRM complex is a hot rolled
coil. The cold rolled products are broadly under the categories:
 Annealed coils
 Galvanised coils
 Cold rolled full hard coils
The cold rolled products from the CRM complex are designed to cater various market
segments such as construction, general engineering, automobile, white goods,
packaging and others.

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What is cold rolling?
It is the process by which hot rolled strip is introduced between rollers and squeezed
or compressed to desired thickness. The amount of strain introduced determines the
properties of finished products.
Need for cold rolling
 Good formability
 Superior surface finish
 Reasonable strength
 Close dimensional tolerance
CRM process flow at TATA
STEEL:
1. Pickling(to remove oxides and scales)
2. Cold rolling in tandem mill to desired thickness.
3. Batch annealing for stress relieving.
4. Skin passing to remove luder lines, develop mechanical properties, impart
desired surface finish, and improve flatness.
5. Recoiling and inspection.
6. Packaging as per customer requirement.
7. Finishing despatch

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Process flow in CRM:


Departments in CRM:
 Pickling line and tandem cold mill (PLTCM)
 Electro cleaning line (ECL)

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 Batch annealing furnaces (BAF)
 Skin pass mill (SPM)
 Continuous galvanising lines (CGL)
 Recoiling and inspection line (RCL)
 Coil packaging line (CPL)

Brief explanation about CRM
 The hot rolled coils produced at Hot Strip Mill (HSM) are input to the CRM
complex for further processing.
 First, the hot coils are passed through the pickling section where the strip
surface is cleaned using low concentration HCL solution (HCL % varying from
12-18%), making them ready for cold rolling.
 This is followed by Trimming Section where the edges of pickled hot rolled
coils are trimmed, if necessary.
 The coil is then fed into the main mill, i.e. Tandem Cold Mill (TCM). TCM is a
five mill stands, each having three sets of rolls names as Work Rolls (WR),
Intermediate Rolls (IMRs) and Back up Rolls (BURs), by passing through which
the strip thickness in reduced in a controlled manner to the desired target
thickness value (0.25 to 3.2 mm).
 This completes the process of cold rolling and output of the TCM is CR Coils or
Cold rolled Coils.
 From here the two-third of the product goes Batch Annealing Furnace (BAF)
where the coils are stacked covered. The stacks are heated and cooled in a
controlled cycle in a 100% hydrogen atmosphere to relieve the internal stress
developed during the cold Rolling. This process improves the mechanical
properties of the Cold Rolled Sheets.
 The Skin Pass Mill (SPM) takes care of the coils annealed in BAF by passing
them through a single stand high speed mill with two pair of rolls. The
objective is to improve the surface finished, impart the correct surface texture
and to control the mechanical properties as per customer requirement. To
protect these coils from environmental impacts, oil is also sprayed at the exit
of the SPM, before recoiling.
 The coils are properly inspected for any surface defects, edge defects or any
other defects and re-oiled for rust protection in any of the three Recoiling
Lines (RCL 1, 2 & 3).

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 The remaining one-third part of the production from PLTCM goes to
Continuous Galvanizing Lines 1 &2 where coils are again cleaned, rinsed and
dried, L-annealed/ heated and taken through a MOLTEN ZINC BATH for a
continuous uniform coating of zinc. This zinc coating helps to give a sacrificial
layer on the cold rolled strip for corrosion protection.
 All the coils produced through BAF-SPM route or CGLs route are sent to the
Coil Packaging Line (CPL) for final packaging. The coils are packed based on
customer, grade, use, and other customer specifications.
Coil Packaging Line

Coil Specifications:
 Material : CRCA /Galvanized coil
 Width : 800 mm to 1580 mm
 Thickness : 0.25 mm to 3.2 mm
 Coil ID : 508 mm to 610 mm
 Coil OD :900 mm to 1900 mm
 Weight : 3 to 28 metric tonnes
 Output Rate : 13.5 coils / hour

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Description:
The Coil Packing Line (CPL) is an important part of Cold Rolling Mill (CRM) Process.
Here the coil is packed and made ready for the dispatch to the customers. Hence,
CPL links the CRM to the customers.
As the packed coils are as per the requirement of the customers, each coil has
different packing codes which contain the different types of packing material used
and different types of strapping.
Need For Packaging:
 To protect the coil from extreme climatic conditions.
 Protection of the product while transit by air, water, road, etc.
 Protection of the products while being handled at different godowns,
warehouses, etc.
 To provide strength for stacking and storing.
While packaging every coil moves through Coil Tracking and Transport System (CTTS)
for each operation and have proper location identity.
The Coil Packaging Line has six coil cars and 15 work stations. Each working station
has a different task that must be completed within the specified time. These tasks
are film wrapping, circum-strapping, eye machine strapping, etc.

Stations in Detail:
Here are six coil cars in Coil Packaging Line. All the saddles are provided with
proximity sensors and all the coil cars are controlled and monitored through
PLC .The operator receives the signal of coil loading position and accordingly
the car moves from home position to pick up the desired coil and go to the
predetermined empty unloading saddles.
Coil Packaging Line is divided into three main sections:
1. Entry Feeding System

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2. Coil Packaging Line
3. Evacuation System

Entry feeding system:

Entry Feeding system comprises of following sub-systems :
 Coil Car P505- This coil car is used to move the coil from the PQ bay to the RS
bay.
 Coil Car P506- This coil car is used to move the coil from the PQ bay to the TU
bay.
 Coil Car P8.1- This coil car is used to place the coil from the four legged saddle
and place it on the saddle at the entry side of the coil packaging line.
 Coil Car P8.2- This coil car places the coil on the saddle at the entrance of the
coil packaging line.
 RS Bay cranes #19 & #20- These cranes are used for keeping the packed coils
from the evacuation system to the storage yard from where they are loaded
into trucks or wagon carts.
 TU Bay Cranes #21 & #22- These cranes are used for keeping the packed coils
from the evacuation system to the storage yard from where they are loaded
into trucks or trains.

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As per the desired sequence coil cars 8.1 and 8.2 gets operated and pick up the coil
from the saddle and deliver to the four legged saddles at the entry side of the CPL.
Anti-collision sensors are used to avoid clashing of the coil cars.

Stations of CPL:
1. Station 1:-

Here coil enters either by crane feeding or by coil car. Coil can be fed either by
coil car P8.1 or by P8.2. In this station coil is kept on walking beam by using TU
bay and RS bay.

2. Station 2:-

In this stage labelling of coil is done. All the specifications are cross checked by
comparing the label pasted on the coil with the chart provided to the supervisor.
If data is mismatches, then STATION 3 supervisor informs the pulpit associate.
Pulpit associate rejects coil from the system & coil passes without packing. Plastic
ID applied to the coil.

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3. Station 3:-

Coil inspection and repairing is done in this stage. Inspection is done by rotating
the coil. Dead marks and damages are checked. If the coil is damaged then,
repairing of coil done by the workman. As per the packing code, wrap with either
HDPE or Strength fabric. After wrapping, job completion given from the operator
panel.


Issues with the coils:
 ID telescopic

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 OD telescopic

 Bad build up


 ID/OD rusted

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 Edge damage


 ID damage OD damage

 Gas cut
 Extruded chips
 ID collapse
 Outer wrap bulge

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 Label data mismatch
 Tong liner
 Outer wrap loose

 Inner wrap loose

 Dent mark

4. Station 4:- Coil centring is done in this station. In this station by the help of
sensors it is checked whether the coil is in centre or not. All the activities of
sensors are controlled by control room. Coil is centred either in auto mode or
manual mode.
5. Station 5:- Coil wrapping is done in this stage. For wrapping process coil master
machine is used. Packing is done according to the packing codes provided by the
customers. There are two types of films which are used for wrapping –

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VCI film wrapping:-
 VCI stands for volatile corrosion inhibitor.
 It is a type of corrosion inhibitor.
 Used to protect coils against corrosion where it is impractical
to apply surface treatments.
 They slowly release compounds within a sealed airspace that
actively prevent surface corrosion.

Non-VCI film wrapping:-
 It is a simple film
 It is just used for covering the coil.
 It doesn’t protect from corrosion.
6. Station 6:-

This station is used for metal wrap operation. Metal wrap is used for cushioning.
Metal wrapping makes the coil outer surface spongy, which prevents the coil
from sudden breakage. It is done by applying blue film on the outer surface of the
coil.

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Safety:-
 Not to stand on the walking beam, while working use a safety platform.
 Use proper knife to cut the metal wrap.
7. Station 7:-

In this station coils are covered with metal jackets.
 If coil is VCI film wrapped then bottom metal jacket and particle board side
disk along with metal side disk is applied according to the width and diameter
of the coil and the outer edge is sealed with filament tape.
 If coil is wrapped with HDPE then top and bottom metal jackets and side disk
as per required width is applied and outer edge is sealed with filament tape.
After the entire job is finished, job completion is given from panel board.
8. Station 8:-

In this station, as per coil inner diameter, Hot Rod Inner Diameter (HRID)
protector is inserted which covers the inner surface and protects it from any kind

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of damage. After completion of the job, the job completion is given by operator
from panel board.









9. Station 9:-

In this station, Galvanised plane outer diameter protector (GPOD) and HRID
application takes place. GPOD protects outer diameter from any breakage or any
damage.
10. Station 10:-

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In this station, circum-strapping is done by the circum-strapping machine.
Circum-strapping increases the flexibility and improves the package stability.
11. Station 11:-



In this station, the eye-strapping machine is used for strapping. This strapping
cycle is initiated upon receiving the coil in the strapping station. With the
electrical interlock the walking beam is prevented from moving any further till the
strap is applied.
12. Station 12:- The packed coil is finally weighted at this station. Weighing
machine installed at this station is Model No. : xxxxxxx make: Avery Weighing
System. From CTTS PDI (Coil Transfer and Tracking System Processed Data
Information) screen, pulpit associate gives checklist to the station supervisor

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which contains coil details like coil thickness, width, packaging code, etc. The
supervisor cross checks the coil data with the printed label data. If the data is
correct, label is pasted and declared as packed. If the data is incorrect, then the
coil is made hold from system by pulpit associate for further decision.
13. Station 13:-

In this station, centre circum-strapping is done manually to ensure that no
manual interruption should take place between the ways from producer to
customer.
14. Station 14:- This station is kept as buffer station. In case any station stops
working this station is used.
15. Station 15:- Coils are dispatched through P9.1 coil car or by P9.2 coil car

Evacuation System:-
Coil car no. 9P509.1 and 9P509.2 – These coil cars are provided at the exit end of the
CPL. Coil car P9.1 is also known as D1 and the coil cal P9.2 is also known as D2. These
coil cars picks up the packed coils from the saddle and load on the stationary saddle
provided at either side. The coils will be evacuated from the saddle with the help of
crane. Anti-collision sensors are used to prevent clashing of coil cars.

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Layout Of Coil Packaging Line (CPL):















PQ

TU
PQ

RS
P8.2
P9.2
Train
Track
Loco
Wagon
P8.1
P9.1
TRUCK
RCL
#1
RCL
#2
CGL2 CGL1 SPM
St. 1
.
.
St. 15
PQ Bay
Crane 17, 18
C
r
a
n
e
C
r
a
n
e

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Packing Consumables:-
1. Metal ID Protector :
Material: Hot Rolled steel
Size: 508/ 610 mm
Outer Diameter: 495mm to 595 mm
Circumference: 1655mm to 1968 mm
Thickness: 2.00 mm
Face x leg length: 50 x 75 mm
Overlap: 100 mm
Colour: Blue painted
2. GP-OD protector
Material: GP coil
Outer Diameter: 900 to 1900 mm
Thickness: 0.80 mm
Face x leg length: 60 x 120 mm
Overlap: 150 mm
3. GP Side Disc :
Material: GP coil
Inner diameter: 508mm/ 610mm
Outer diameter: 900 TO 1900 mm
Thickness: 0.5 mm (Domestic)

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4. Particle Board Side Disc :
Material: Particle Board
Inner diameter: 508mm to 610mm
Outer diameter: 900 to 1900 mm
Thickness: 2.5 mm

5. Filament Tape :
Size: 2”/ 3”/ 5”/ 8”
Width: 44 mm/ 72 mm/
Tensile strength: 70 Kg/ Inch
Length: 50 meter per roll

6. Laminated HDPE Fibre :
Material: laminated HDPE fabric- virgin quality
Width: 1.83 / 2.50 / 3.0 meter



7. VCI Dura met Paper :
Width: 1.83 / 2.13 / 2.45 / 2.74/ 3.05 metres
Thick/gauge: 130 GSM
Nominal thickness: 0.21 mm

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8. Volatile Corrosion Inhibitor(VCI) film :
Material: Stretch Film
Width: 245 mm
Thickness: 50 microns
Core ID: 76 mm
Core width: 250 mm
Net weight: 8.0 kg

9. Non-VCI film :
Material: Stretch film
Width: 225 mm
Thickness: 50 microns
Core ID: 76 mm
Core width: 250 mm
Net weight: 8.0 kg

10. Plastic ID:
Material: HDPE
Size: 508 & 610 mm
Face x leg length: 100 X 50 mm
Thickness: 2 mm
Length: 1655 mm
Length: 610 mm to 1955 mm

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11. Plastic OD:
Material: HDPE
Face x Leg Length: 75 x 75 mm
Thickness: 1.35 mm



12. Strap :
Material: High Tensile Steel
Width: 31.75 mm
Thickness: 0.64 mm
Breaking strength: 1900 - 2398 kg’s

Controller used in CPL:-
Every automation process employs a particular controller by which the whole
automation process is controlled and carried out properly. It defines the logic
associated with machine operation and required conditions for operation i.e.
interlocks and the sequence of operation. Controller executes written logic for
operation. During execution system check for various interlocks, if all interlocks
are opened simultaneously then only the logic is executed otherwise not.
The entire control system of CPL can be divided into following parts:

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1. Control system for Coil Cars :
All the Inputs from field sensors of Coil cars area are connected to
respective Input card mounted in an extension unit of PLC. This
extension unit is called Remote Input Output Unit. ET200 cabinet has
following cards in each cabinet:
 Network Interface card – which interfaces with main unit.
 Digital Input card – Takes input from field sensors
 Digital Output – Gives output to the field actuators, solenoid valves
etc.
 Analogy Input – Takes continuous type input like 0-10V signal or 4-
20mA signal.
 Analogy Output – Gives continuous type output like 0-10V signal or
4-20mA signal.

Coil car Control System comprises of many control equipments. Some of them are:-
 PLC of SEIMEN S7 400
 Drives:- SEIMEN’S Master drive
 Feedback elements:-
1. LASER Distance meter
2. Coil sensing by saddle photo sensor(BALLUF)

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2. Control system for Walking beam :

I Walking beam motion is controlled by ROCKWELL AUTOMATION (IMC-AEC).
It is driven by hydraulic power.
II Walking beam Control System comprises of many control equipments. Some
of them are:-

 PLC of ROCKWELL AUTOMATION of Allen Bradley 5/40 E model.
 Actuators: -REXROTH Proportional Valve
 Feedback elements :- Tempo sonic sensor ( used in traverse motion)
Proximity sensor (used in vertical movement)

3. Control system for Coil Master :
I Coil master is used for VCI film wrapping.
II Coil master Control System comprises of many control equipments. Some of
them are:-

 PLC : Model 5/40 Eof Allen Bradley (or ROCKWELL AUTOMATION).
 Drives: -Power Flex Drives by ROCKWELL AUTOMATION.
 Actuator: - Servo Motor

4. Control system for Strapping machines :

I. The Circum-strapping machine is used to strap along circumference at two
ends of the coil one at a time.
II. Coil master Control System comprises of many control equipments. Some of
them are:-

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 PLC : Model 5/40 E of Allen Bradley (or ROCKWELL AUTOMATION).
 Drives: - Power Flex Drives by ROCKWELL AUTOMATION.

PROGRAMMING LANGUAGE OF THE PLC
It can have three different programming languages, such as:
 LAD – Ladder diagram
 STL – Statement List
 FBD – Functional Block Diagram

i. LADDER DIAGRAM
Ladder logic has evolved into a programming language that represents a
program by a graphical diagram based on the circuit diagrams of relay logic
hardware. Ladder logic is used to develop software for programmable logic
controllers (PLCs) used in industrial control applications.

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Fig: - Ladder Logic

ii. STATEMENT LIST
Statement list is a programming language using mnemonic abbreviations of Boolean
logic operations. Boolean operations work on combination of variables that are true
or false. A statement is an instruction or directive for the PLC.
Statement List Operations
* Load (LD) instruction.
* And (A) instruction.
* Or (O) instruction.
* Output (=) instruction.

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iii. FUNCTIONAL BLOCK DIAGRAM
The Function Block Diagram (FBD) is a graphical language
for Programmable Logic Controller(PLC) design that can describe the
function between input variables and output variables. A function is
described as a set of elementary blocks. Input and output variables are
connected to blocks by connection lines.

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SOME OF THE ELECTRICAL EQUIPMENTS AND SENSORS
I. LOAD CELL
A load cell is a device that is used to measure weight or force. When a
force is applied to it in a specific manner, a load cell produces an output
signal that is proportional to the applied force. Strain gage load cells are at
the heart of the majority of weighing and force measurement devices
produced today. One end of a load cell is typically supported on a rigid
structure while the other end supports a load-receiving device through
which the load or force is applied. Load cells can be used individually or in
combinations in weighing devices, as dictated by the geometry of the
object to be weighed.


Fig: - Load Cell

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II. Walking Beam Control:

 Walking beam is controlled by PLC of Allen Bradley 5/80 and two 5/40
PLCs. One of 5/40 PLC is used to control Eye Machine and Circum-
Strapping Machine, other is used to control Coil Master while the rest is
controlled by 5/80 PLC. Three different PLCs are used to avoid interlock
mixing and avoid complexity of control.
 Only ladder logic is used in walking beam PLC.
 120 volts is given to both AC as well as DC inputs.
 Analog output is in form of 12 bits.



Fig:-PLC of Walking Beam

 There are two walking beams interconnected mechanically so as to lift all
the 15 coils simultaneously so as to transfer each coil to next station.
There are 8 hydraulic cylinders used to lift walking beam and two
cylinders for transverse motion of walking beam. Walking beam is
provided with various types of sensors such as proximity switch, distance
transducers, load cell to control and automate motion of walking beam.

35. 35

 The walking beam is provided with Tempo sonic sensor (linear position
transducer) to provide feedback about the distance travelled by the
walking beam.



 Two proximity sensors are used to control the upward and downward
movement of walking beam.


 At one station weight of coil is measured by Load Cell.
 The different movement of walking beam as shown in diagram:-

36. 36









RET-Right End Top
LET-Left End Top
LEB-Left End Bottom
REB-Right End Bottom

Initially the beam is at REB position, it lifts up with the coil and this position is RET, it
moves towards left according to operator view, and reaches LET position, now it
moves down keeping coil to the next position reaches to LEB position and again it
moves back to REB position, this cycle continues.

III. COIL CAR CONTROL

 Coil car is controlled by PLC of SEIMENS S7-400 PLC.
 It consists of power supply, processor, Digital Input (DI), Digital Output
(DO), Analog Input (AI), Analog Output (AO).
 Battery backup facility is given to CPU processor.
 24 V DC voltages are given to Power Supply.
 Communication by Radio Frequency (RF) and Fibre Optics (FO).
 There are two steps for transfer of coils from coil car segment to walking
beam carried out by entry side coil cars 9P508.1 and 9P508.2

REB
RET LET
LEB

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1. Entry to Delivery: This sequence is used to transfer coils from
entry side of coil to delivery side.
2. Delivery to Walking Beam: This sequence is used to transfer
coils from delivery side to walking beam.

MODES OF PROGRAMMING: -
There are three modes of programming
a. Ladder mode
b. STL Mode :- Statement List Mode
c. FBD mode :- Function Block Diagram Mode

MODES OF OPERATION OF COIL CAR: -
There are three modes of operation of coil car
a. Auto mode
b. Semi-auto mode
c. Manual mode

About Coil Cars in CPL
 There are 6 coil cars to feed coil to CPL and evacuate from CPL after
packaging.
 Coil cars 505 and 506 transfer coil from PQ bay to RS bay and TU bay
respectively.
 P8.1 feeds coils to CPL from RCL#3 side and coils of CRCA route (output
of SPM).

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 P8.2 feeds coils to CPL from RCL#1&2 side and coils of CRCA route
(output of SPM).
 After packaging, P9.1 evacuates coils from CPL and transfers to TU bay
side.
 After packaging, P9.2 evacuates coils from CPL and transfers to RS bay
side.
 Coils are picked from P9.1 or P9.2 saddles through crane and kept in RS
bay, ST bay or TU bay, from where coils are dispatched to final
customer.

The Coil Master:

 The package concept is an integral part of the Coil master design. The
system puts a tight layer of film over all surfaces of the coil which
eliminates most of the air from the package. By reducing the amount of air
in the package, the potential for moisture to form is reduced, thereby
preventing rusting.
 The ancillary packaging is then applied which may include inner diameter
protectors, outer diameter protectors, side wall protectors or belly wrap
material. This material can be applied manually or by the use of machines.

39. 39

This packaging protects both the coil and the first layer of film. The
ancillary product can be made from plastics to maintain a completely
recyclable package
 Then a second layer of film is then applied which holds the ancillary
package in place and further protects the inner airtight layer of film. Since
the entire coil is sealed in a waterproof package, any external moisture
runs off the package.
 The film dispensing shuttle is designed to drive itself around the track
(rack and pinion system) at a speed up to 4.2 m/s. Power is delivered to
the track through conductor rails. A 45 Hz motor is mounted on the
shuttle, power given is controlled through Variable Frequency Drives.
 The system can be operated by one operator utilizing a user-friendly,
menu driven, touch-screen panel. The operator panel also houses E-Stop
and lockout controls. The system is programmed with a self-diagnostic
package. Should a fault occur, it will be identified on the operator control
panel.

Circum-strapping Machine:

40. 40

The Circum-strapping machine is used to strap along circumference at two ends
of the coil one at a time. The machine has following parts:
 Head
 Jaw
 Face gate
 Bayonet
There are two modes of operation of strapping machine:

I. Auto Mode:
In the auto mode strapping cycle starts automatically when signals
are received from photo sensors confirming that coil is placed in the
region of strapping machine.
II. Manual Mode:
In manual mode strapping is done through series of push button the
process being the same as in auto mode. Manual mode is required if
we need to control the number of straps like we need to strap at the
centre too.
Eye Strapping Machine:

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Eye strapping machine is used to strap at the eye of coil. There are two eye
machines used to strap coils- Eye Machine 1 and Eye Machine 2. The numbers of
straps vary from 4 to 6 depending on different packing codes. If the number of
strap is 4 the each strapping is done at angle of 90 degrees and if number of strap
is 6 then strapping is done at 60 degrees.

Sensors Employed:
1. Laser Sensor:
It is a range finder which uses a laser beam to determine the
distance to an object. It sends a laser pulse in a narrow beam
towards the object and measuring the time taken by the pulse
to be reflected off the target and returned to the sender. It is
used for moving the coil car to the desired destination.

2. Limit Switch :
It is a type of switch which defines limit. It has two types of
contact:-
o Normally closed (NC) Contact
o Normally open (NO) Contact
It is used in safety platform. It is used for stopping coil cars if
walking beam is in operation.

3. Anti-Collision Sensor: It is used to prevent two coil cars
from colliding.

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Working principle:
 The anti-collision system is a safety device to avoid the collision
of two electric overhead travelling coils working on the same
rail.
 It consists of an emitter and sensor module and a special
reflector. The emitter emits the infrared waves in the direction of
reflector. The reflector reflects these infrared waves to the
sensor. The sensor senses the presence of these reflected
infrared waves and activates an alarm signal and stops or
reduces the speed of the coil car. Thus if two coil cars are away
from each other then the reflected waves will not reach the
sensor and the coil cars operate normally.
 Each set consists of an emitter or sensor module and a reflector.
For one pair of coil car two set of anti-collision systems are
required.

4. Tempo sonic Sensor: It gives the feedback about the
distance travelled by the walking beam.

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Working Principle:
I. A current pulse is sent through the waveguide. A Position
magnet is mounted on movable part whose position has to
be measured. There is no mechanical contact to waveguide.
II. The interaction of two magnetic fields produces a
mechanical strain pulse, which travels at ultrasonic speed
along the sensing element. A mechanical pulse converter
system generates an electric signal. The electric pulse is
processed by sensor electronics
III. The magnetic position is determined accurately by speed
measurement, whereby the magnet position is a function
between start and stop.

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Conclusion:
This is just a brief note and idea about the whole system which is useless until
and unless it is aided by frequent visits to the sites. But still we cannot at all
underestimate its importance as it can serve as a fundamental tool for anybody
who wishes to understand the basics of the CPL along with the process of the
ECR.
There Coil Packaging Line consists of six coil cars. All the saddles are provided
with Coil sensing proximity switches. All the coil cars are controlled and
monitored through PLC. The operator receives the signal of all coil loading
positions and accordingly the car moves from Home position to pick up the
desired coil and will go to the predetermined empty unloading saddles thereby
completing the process to be carried out in the coil packaging line.
CPL is the last section of the steel making process and plays a very important role
in the company’s outsourcing.