Electrical Internship report ( WONDER CEMENT )

1. SUMMER INTERNSHIPREPORT
ON
(A COMPREHESIVE STUDY OF THE EQUIPMENTS AND
TECHNIQUES IN CEMENT MANUFACTURING)
AT
WONDER CEMENT LIMITED
NIMBAHERA, CHITTORGARH (Raj.)
(An integrated unit of R.K. Marble group)
SUBMITTED TO: - SUBMITTED BY:-
DR. MAHENDRA LALWANI NAVEEN GEHLOT
(ASSOCIATE PROFESSOR) BATCH- EE-3
ELECTRICAL DEPARTMENT ROLL NO-16/547
UCE,RTU, KOTA
UNIVERSITY DEPARTMENTS,
RAJASTHAN TECHNICAL UNIVERSITY
KOTA (RAJ.)

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PREFACE
This report has been given by the author to convey the information about different sections and
departments of Wonder Cement Limited. Different specifications, prospective and processing in each
section while producing cement, is being discussed in the most convenient manner for the readers. We
have tried to enhance history, literature, survey and importance of the manufacturing process. Also
schematic figures are shown in each section to discover a better understanding. Proper statistics and
parameters of all the major Equipment are also presented to make a better analysis of the project in
comparison to other major cement manufacturing plants.
Author has certainly made conscious efforts in imparting as much knowledge and information as
possible to the readers in this report. I express my sincere thanks & regards to Wonder Cement Plant, for
giving me the opportunity to study on “The Cement Manufacturing Process.”

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ACKNOWLEDGEMENT
I have taken efforts in this training. However, it would not have been possible without the kind support
and help of many individuals and organizations. I would like to extend my sincere thanks to all of them.
First and foremost I express my heartiest thanks to Mr. Ashok Acharya (Mines Department) and Mr.
Abhishek Srivastava (Process Department). I also thanks to MR. Vimal Joshi (Quality Control
Department), Mr. S.C. Junwal (Electrical Department), MR. Pradeep upadhayay (Instrumentation
Department) and Mr. Vivek Sharma (Packing Plant).
I also express my gratitude to Mr. Rahul Chouhan and Mr. Sanjay Tailor (Electrical Department).
And lastly, I would like to thank my group member for his kind support to complete this project work
successfully.
I wish to express my deep sense of gratitude to Dr. Mahendra Lalwani, who through his benevolent
guidance has enabled me to complete my project. He has been a great source of inspiration to me all the
way. Without his keen interest, incessant encouragement and invaluable suggestions, this report could
not have attained its present shape.
Date……… NAVEEN GEHLOT

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TABLE OF CONTENTS
1. INTRODUCTION
2. CEMENT MANUFACTURING PROCESS (FLOWCHART)
A. MINING
B. CRUSHING
C. RAW MILLING
D. PYRO-PROCESS
E. CEMENT GRINDING
F. PACKING PLANT
3. DESCRIPTION OF ELECTRICAL ENERGY
4. MOTOR STARTER CONFIGURATION
5. CONTROL PANELS
6. INSTRUMENTATION & AUTOMATION IN CEMENT
7. CONCLUSION

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INTRODUCTION
ABOUT COMPANY
Wonder Cement is a cutting-edge cement manufacturing company with an ambition to
establish itself as a leading player in the industry. Enriched with the heritage of R.K.
Marble, a leading name in the marble industry, our corporate culture is built on the values of
quality, trust and transparency. An emphasis on technological superiority enables us to
differentiate our offering through impeccable quality and effective communication. With an
extensive network of dealers & retailers, we own a position in the premium segment of the
market.
The cement plant, located in Nimbahera, District Chittorgarh, in Rajasthan, started with
Line 1 in March 2012 with a production capacity of 3.25 Million Tons per year.
The state of the art manufacturing unit was established in technical collaboration with
ThyssenKrupp and Pfeiffer Ltd. of Germany, world leaders in cement technology, to
produce cement at par with international standards. Special efforts were taken to ensure that
the plant upholds the latest environmental norms and with the help of a reverse air bag
house, ESP and a number of nuisance bag filters, we ensure to keep the plant clean & dust
free.
The commencement of Line 2 in September 2015 increased the production capacity to 6.75
Million Tons per year. With the launch of our first grinding unit in Maharashtra adding a
capacity of 2 million tonnes annually, our capacity increased to 8.75 Million Tons per year
in August 2018. With the launch of Line 3 in Nimbahera, District Chittorgarh, in Rajasthan
on July 2019, and the upcoming grinding unit in Madhya Pradesh the total capacity is
expected to scale upto 11 Million Tons per year by the end of the year.

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CEMENT MANUFACTURINGPROCESS
Fig.: Cement Mfg. Process

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MINES
SECTION-A
MINING
The Mining sector in each cement plant enhances its presence for manufacturing and production of
cement. Limestone is the basic element of producing cement and is always found naturally under the
earth and so it is extracted by mining.
Wonder cement limited (WCL) has its mining area 3kms away from the main processing plant. The
plant has a total area of 740 hectares (740x10, 000 sq. meters) under it on lease for about 30 years
whereas only up to 400 to 500 meters of limestone is being extracted from the mines at present.
The amount or quality of limestone is predicted by data mine software in which a spectral graph is
developed. The curves obtained in this graph shows the required nature of limestone, then the top soil
is removed and the solid part is then used for plantation in the cement plant itself and this process is
called slice lining. Now a deep Hole blast is produced with a diameter of 4.5 inches hole. Blasting is
carried out on the area of extraction and for that explosives like blast booster and ammonium nitrate
are used.WCL has its own explosive magazines to store these explosives. There are shock tubes
which are also a part of these explosives used at a rate of 3-5 mg per explosive.
Fig.: Mines of Wonder Cement

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SECTION-B
CRUSHING
LIMESTONE CRUSHER
As the name suggests, the first phase of cement processing starts from this section. This sector of
cement manufacturing is key to forth coming cement’s manufacturing process. The limestone being
extracted from the mines is dumped into a hopper surrounded by a thick metallic sheet through
dumpers. The limestone is fed into the wobbler through apron feeder which is motor operated. The
particles with a size of up to 1metre or more are sent to L.S. Crusher where adequate size of material
is obtained through impact type of crusher.
This crushed material is now sent to surge hopper for storage through belt conveyer. On this path of
belt conveyer a machine called Bulk analyser is setup to check every possible quality of limestone
like its sulpur or other foreign content. Also it is the only machine of such a kind to be erected at
WCL in comparison to any other cement company in rajasthan.A belt weigh feeder with load cell is
provided on conveyer belt to check the amount of material being fed. Bag filters are essentially setup
wherever dust is produced to prevent its wastage. Now limestone from surge hopper is transferred to
staking conveyer where large stockpile of 25,000 to 30,000 tons is prepared by stacker and it is then
reclaimed through
Raclaimer having metal blades with bucket type shapes. The material is fed on to another conveyer
called Reclaimer belt up to raw material hoppers. This belt in WCL is considered as the longest
having a length of 750m. There are two L.S. hoppers with a capacity of 800 tons in each.
Major components of crusher house
Considering the fact that crusher house is a vast section itself but few of its major components are as
follows:
Apron conveyor
Wobbler
Crusher impacker (limestone)
Bulk analyser
Stacker
Reclaimer
Truck trailer

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SECTION-C
RAW MILL
Fig.: Raw Mix Hopper at WCL
Wonder Cement Limited has the MPS 5600B vertical roller mill which is used for drying and
grinding cement raw material. Conveyor belts take the raw material to the mill, the magnetic
separator and a metal detector are located at the conveyor belt that transfers the material to the
mill. Passing through a 2-way chute, the material is delivered to a mill via a rotary loch
providing an air seal. If the metal detector responses, the 2-way chute is switched over directing
the contaminating material to a waste receptacle. The material supplied to the mill is controlled
by mill differential pressure. The material is ground to the required fineness in the mill and is
dried simultaneous
Various drying gases (kiln gases, cooler gases and hot gases from a hot gas generator) serve to
dry the material. If possible the hot gases of kiln as well as of cooler are always used for drying
process, while the heat output of hot gas generator is adapted to suit the changing demands.
The finished product is carried out of the classifier with the gas flow from which it is largely
separated in battery of cyclones.
The downstream filter de-dusts the remainder of the exhaust gas flow. The gas volume flow
required for the grinding process is produced by a fan which is procured by the Pfeiffer India.
The gas volume flow is set either by a regulating device or by fan drive motor. For taking any
spillage material, the mill is equipped with an external material recirculation. Any material
falling through the nozzle ring is covered by scrappers arranged below the grinding bowl
through the reject chute, from there the material is returned to the mill feed by means of a
conveyor belt and a bucket elevator. For emptying the mill in case of maintenance; conveyor
belts, bucket elevators and 2- way chute enable the material to be transported to the waste
receptacles.

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Fig. ( Schematic Diagram Showing Vertical Roller Raw Mill in Cement Industries)

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SECTION-D
PYRO PROCESSING
In pyroprocessing, the raw mix is heated to produce portland cement clinkers. Clinkers are hard,
GRAY, spherical nodules with diameters ranging from 0.32 - 5.0 cm (1/8 - 2") created from the
chemical reactions between the raw materials. The pyroprocessing system involves three steps: drying
or preheating, calcination (a heating process in which calcium oxide is formed), and burning
(sintering). The pyroprocessing takes place in the burning/kiln department. The raw mix is supplied to
the system as a slurry (wet process), a powder (dry process), or as moist pellets (semidry process). All
systems use a rotary kiln and contain the burning stage and all or part of the CALCINING stage. For
the wet and dry processes, all pyroprocessing operations take place in the rotary kiln, while drying
and preheating and some of the calcination are performed outside the kiln on moving grates supplied
with hot kiln gases.
The pyro section is the most vital part of any cement plant. It mainly consists of following parts:-
Pre-heater
Rotary kiln
Clinker silo
Pre-Heater
The main function of the pre-heater cyclone is preheating of the raw meal, from outlet hot gases of the
kiln. 6-stage double string in the line CALCINER system is used for this purpose. Initially raw meal
entering the kiln from last stage of the pre-heater is fed between 6th and 5th stage then it goes to 6th
cyclone by hot air. There the material is being separated and it goes to 5th cyclone through 4thriser
duct and the process continues adjacently. After 2nd cyclone the material goes to pre CALCINER
duct. Here calcination of the material is completed upto 90%. The material then reaches the kiln after
passing through 1st cyclone. The detailed description of the process in pre-heater is performed by the
following equipment involved in it.
Fig. Pre-heater at WCL

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ROTARY KILN
Fig. Rotary Kiln at Wonder Cement
The rotary kiln is designed for powdery, small sized or sludgy feed material.
For this purpose, a special rotary kiln burner is located in the rotary kiln outlet in
kiln hood. Due to slope and rotation of the kiln, the material feds in the kiln
inlet which is conducted to the kiln outlet. The downstream kiln hood serves
as an air lock and as a connection to the subsequent unit. In order to protect
rotary kiln shell as well as to prevent excessive heat loss the kiln is especially
equipped with a refractory lining. The rotary kiln shell consists of individual
sections that are welded in the workshop. The material quality is selected in
accordance with temperature stresses to be expected. The rotary kiln is
supported on tyre /support roller. In axial direction the kiln is guided by a
rotary kiln axial thrust system. The driving torque is transmitted from the
rotary kiln drive via girth gear and pinion drive to the rotary kiln shell. These
drives and gears are protected by covers and lubricating devices. As a
transition to the downstream units, a kiln hood is located at the outlet end of
rotary kiln with openings serving access hole to the kiln and as a pass through
for rotary kiln burner. Seals at the kiln inlet and outlet prevent the infiltration of
false air.

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CLINKER SILO
Although clinker storage capacity is based on the state of the market, a plant can normally store 5 -
25% of its annual clinker production capacity. Equipment such as conveyors and bucket elevators is
used to transfer the clinkers from coolers to storage areas and to the finish mill. Gravity drops and
transfer points typically are vented to dust collectors.
Following are the basic categories defining a clinker silo-
Material distributor
Silo type
Surge bin
Fluildor
Material Distributor:-
The material to be conveyed is fed into the distributor vessel via a inlet connection. The aeration air
passes through the air connection into the aeration floor. The aeration air passes finely dispersed
through the pores fabric floor and fluidizes the material that is being conveyed. The installed dam
ring uniformly distributes the material to the outlet connection that are arranged around the
circumference of the vessel. The aeration air is exhausted through the de-dusting connections.
The necessary aeration air, volume is regulated by the damper. The aeration air is supplied to the
pneumatic trough conveyer via the aeration connection at lower housing of the trough conveyer.
The air flow rate is set by means of upstream, manually operated dampers. Here only dry and clean
air must be used.
Fig. : Clinker Silo

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SECTION-E
CEMENT MILL
FINISH MILLING (CEMENT)
Fig.5.1 Cement grinding process circuit
During the final stage of Portland cement production known as finish milling, the clinker is ground with
other materials (which impart special characteristics to the finished product) into a fine powder. Up to
5% gypsum and/or natural anhydrite is added to regulate the setting time of the cement. Other chemicals,
such as those which regulate flow ability or air entrainment, may also be added. Many plants use a roll
crusher to achieve a preliminary size reduction of the clinker and gypsum. These materials are then sent
through ball or tube mills (rotating, horizontal steel cylinders containing steel alloy balls) which perform
the remaining grinding. The grinding process occurs in a closed system with an air separator that divides
the cement particles according to size. Material that has not been completely ground is sent through the
system again.

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DESCRIPTION OF ELECTRICAL ENERGY :-
Power requirement and Source power requirement for the existing integrated cement plant (Line-I,II
&III) is 109.60 MW. Total power requirement after proposed expansion (line-IV) will be 157.6 MW
which will be sourced from Captive Thermal Power Plant (40+30=70 MW), WHRB (9+9+12+15)= 45
MW) , Captive Solar Power Plant (2 MW), Captive Wind Power Plant (1.5x10=15 MW) and balance
25.6 MW from State AVVNL (Ajmer Vidyut Vitran Nigam Ltd.)
SINGLE LINE DIAGRAM:-
LT DISTRIBUTION :-
HT DISTRIBUTION:-

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1. CAPITIVE POWER PLANT(CPP)
In Wonder Cement has 38MW capitve power plant and planning to take up expansion of cement plant
“Clinker (from 2.0 to 6.0 MTPA), Cement (from 3.25 to 8.0 MTPA), CPP (from 40 to 80 MW), D.G. Set
(from 2.0 to 7.0 MW)” Capitive power plant, also called autoproducer or embedded generation, is
a electricity generation facility used and managed by an industrial or commercial energy user for their
own energy consumption. Captive power plants can operate off-grid or they can be connected to the
electric grid to exchange excess generation.
Our current 38-MW captive power plant is enough for the present Line-1. For Line-2, we will be putting
up another 40 MW power plant but not with the construction of this line. With this second line, we are
putting up a waste heat recovery system of 18 MW capacity. Therefore, there will be a shortfall of 22
MW but actually 18 MW only because 4 MW is internal consumption; our plant requirement is 36 MW.
For the balance requirement, we have a grid connection.” The orders for the 18-MW waste heat system
have already been placed with Thermax and ThyssenKrupp.
FIG:- SLD CPP
FIG.:- CAPITIVE THERMAL POWER PLANT AT WCL

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2. WASTE HEAT RECOVERY SYSTEM (WHRS)
In a cement plant, nearly 35% heat is lost, primarily from the preheater and cooler waste gases. This
corresponds to around 70 to 75 MW of thermal energy. This energy can be tapped by installing a Waste
Heat Recovery system (WHRS).
• 18 MW Cement Waste Heat Recovery Power Plant operational since 2016
• Configuration: 18 MW Power Plant based on waste heat from two kilns of 8500 TPD each
• Consultant: Holtec
• Scope included the fabrication and erection of ducts and duct supports - Total 2000 ton, Diameter 5m
and at height up to 80 m
• One of the largest CWHR power plant in india.
FIG:- SLD WHRS
FIG:- WHRS IN CEMENT PLANT

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MOTOR STARTER CONFIGURATION
Direct on line (DOL) starting
A direct on line (DOL) or across the line starter, the simplest type of motor starter, applies the full line
voltage to the motor terminals.
DOL starting is sometimes used to start small water pumps, compressors, fans and conveyor belts. In the
case of an asynchronous motor, such as the 3-phase squirrel-cage motor, the motor will draw a high
starting current until it has run up to full speed. This starting current is typically 6-7 times greater than
the full load current.
To reduce the inrush current, larger motors will have reduced-voltage starters or variable speed drives in
order to minimize voltage dips to the power supply.
Soft starters
A motor soft starter is a device used with AC electrical motors to temporarily reduce the load and torque
in the power train and electric current surge of the motor during start-up. This reduces the mechanical
stress on the motor and shaft, as well as the electrodynamic stresses on the attached power cables and
electrical distribution network, extending the lifespan of the system.
The motor is adjusted to the machine’s load by controlling the three-phase motor’s voltage supply during
the start-up phase. Equipment is accelerated smoothly, this lengthens service life, improves operating
behavior, and smooths work flows. Electrical soft starters can use solid state devices to control the
current flow and therefore the voltage applied to the motor.
Soft starters are more expensive than DOL starters, but they are widely used due to their convenience
and simplicity.
Variable frequency drives
A variable-frequency drive (VFD; variable speed drive, AC drive) is a type of adjustable-speed drive
used in electro-mechanical drive systems to control AC motor speed and torque by varying motor input
frequency and voltage. VFDs are used in applications ranging from small appliances to large
compressors.
The VFD controller is a solid-state power electronics conversion system consisting of three distinct sub-
systems: a rectifier bridge converter, a direct current (DC) link, and an inverter. Most drives are AC-AC
drives in that they convert AC line input to AC inverter output.
A VFD is extremely versatile and often used in process applications where a constant pressure or flow
needs to be maintained. In addition, because the motor can be run at a slower speed and hence use less
energy, use of a VFD can facilitate significant power savings.
Variable speed drives are generally the most expensive method of motor starting, but their versatility
means they are very widely used.

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Control panel
Wonder Cement, a cutting-edge cement manufacturing company, aims to ride on this growth wave
through an emphasis on technology and quality. Using these levers, it has been consistently overcoming
challenges such as transportation cost of raw materials, finished cement and utilization of pet coke.
The Siemens CEMAT Automation software that is installed at Wonder Cement includes the Process
Optimization solutions KCS and MCS that use actual plant data to make precise predictions about
quality parameters. Plant process parameters that the operator enters manually result in consistent
operation throughout the day. Thanks to the optimization solutions, operators are freed from monotonous
routine work, so they can concentrate on key tasks. Furthermore, at any time the set points in the
controllers can be adjusted to achieve stable production conditions at an optimum level. Additional
advantages include constant production characteristics for consistent results. The solutions are very user
friendly and they can be easily tuned to ever-changing process conditions to optimally run the loops.
The result is improved efficiency through more stable production processes, and better quality thanks to
well-balanced sintering conditions. Furthermore, the lifetimes of the refractory and the equipment have
been extended, and emissions have been lowered.
Motor control center (MCC)
It is an assembly to control some or all electric motors in a central location. It consists of multiple
enclosed sections having a common power bus and with each section containing a combination starter,
which in turn consists of motor starter, fuses or circuit breaker, and power disconnect. A motor control
center can also include push buttons, indicator lights, variable-frequency drives, programmable logic
controllers, and metering equipment. It may be combined with the electrical service entrance for the
building.
MCC's are typically found in large commercial or industrial buildings where there are many electric
motors that need to be controlled from a central location, such as a mechanical room or electrical room.
Power control centre (PCC)
PCC is power control centre. In simple terms or generally a panel which supplies or received H.T power
can be termed as PCC whereas panels which supplies power to L.T motors
PCC is an important part in distribution of power. It generally receives stepped down voltage through
transformer LT line and then redistributes to different MCCs & other power distribution centres.
The Power Control Center has a compartmentalized panel with a current carrying capacity up to
6300Amp. The Power Control Center is a common control panel with different vertical sections from
where the different electric parameters are monitored and controlled. This range of Power Control
Centers is very effective in handling very high current at low voltage.
We believe in offering our clients superior quality Power Control Centers. The Power Control Center has
a compartmentalized panel with a current carrying capacity up to 6300Amp. The Power Control Center
is a common control panel with different vertical sections from where the different electric parameters
are monitored and controlled. This range of Power Control Centers is very effective in handling very
high current at low voltage.
Features:
Robust design
Hassle free operation
Maintenance free

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INSTRUMENTATION & AUTOMATION IN CEMENT
HISTORY & ADVANCES IN AUTOMATION:
The modern cement plant today is equipped with latest technology of automation. The
automation of cement plant is comparable to any industry such as steel, petroleum etc.
Some of the rate feats of Indian Cement Industry are :
· First programmable controller was introduced in 1978.
· Thyristor or Transistor based analogue variable speed AC drive in various
applications.
· First fuzzy control for cement got commissioned in 1987.
· Most powerful advance SCADA/DCS are in use since 1986-2000.
· The cement plants in India are very competitive today; they are very efficient in terms
of thermal & electrical energy consumption, in terms of productivity.
· Some of the latest Plants commissioned in 2004 are operating at 72kWh/ton of 27
Cement.
· The CCR of typical Cement Plant of 1 million tons/annum capacity is equipped with
atleast 4-Operator Stations (OS).
· Seven colour desktops are available for Kiln, raw mill & Cooler burning view and
some communication facility such as Phones, Wireless and PA system etc.
NEEDS OF PROCESS CONTROL AUTOMATION:
Every Industrial Process has three types of main flows:
 Material Flow

 Energy flow

 Information Flow
So the aim of Plant Automation is to identify the Information flow i.e. to take related
information and control Material & Energy Flow in desired manner.

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BENEFITS OF AUTOMATION:
1. Increase in production
2. Improvement in quality
3. Reduction in cost
4. Optimal use of available resources
5. Environmental pollution control
Safety
TYPICAL AUTOMATION MEASUREMENT IN CEMENT PLANT
Crusher–
o BRG Temperature
Stacker & Reclaimer –
o Maximum level of material
o Maximum travel
Ball Mill –
o BRG Temperature
o Oil flow & Pressure
o Sound level
Vertical Mill –
o Vibration
o Presence of metal
Kiln System –
o BRG Temperature
o Shell & Lining temperature
o Position (L.S. UP,DN)
Larger Motors –
o WNG & BRG Temperature
o Cooling Air flow & PR

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Elevators –
o Alignment
o Speed Monitor
Conveyors –
o Alignment (Belt Sway)
o Speed Monitor
SENSOR
A sensor is a device that measures a physical quantity and converts it into a signal which can be
read by an observer or by an instrument. For example, a mercury-in-glass thermometer converts
the measured temperature into expansion and contraction of a liquid which can be read on a
calibrated glass tube. A thermocouple converts temperature to an output voltage which can be
read by a voltmeter. For accuracy, all sensors need to be calibrated against known standards.
USE
Sensors are used in everyday objects such as touch-sensitive elevator buttons and lamps which
dim or brighten by touching the base. There are also innumerable applications for sensors of
which most people are never aware. Applications include cars, machines, aerospace, medicine,
manufacturing and robotics.
A sensor's sensitivity indicates how much the sensor's output changes when the measured
quantity changes. For instance, if the mercury in a thermometer moves 1 cm when the
temperature changes by 1 °C, the sensitivity is 1 cm/°C. Sensors that measure very small changes
must have very high sensitivities.Ideal sensors are designed to be linear. The output signal of
such a sensor is linearly proportional to the value of the measured property. The resolution of a
sensor is the smallest change it can detect in the quantity that it is measuring.
LEVEL SENSOR
GENERAL APPLICATION OF LEVEL SENSOR :
Level Sensors designed to provide accurate and reliable level information of Solids (Powder &
Lumps), Liquids and Slurry applications for point level detection in storage Bins, Silos, Hoppers,
Tanks and any other vessels where material is stored, processed and discharged even at high
temperature/pressure.
FIG.:- LEVEL SENSOR

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FUNCTION OF LEVEL SENSOR
The oscillator generates low-power RF signal which is used to provide signals equal in frequency phase
and amplitude to both, active section and shield section of the probe. The signal applied to the shield is
held constant by use of compensating amplifier. The detector is then used to compare the fixed shield
signal with active signal which varies with the dielectric constant of the material in contact with the
probe. Difference in the signals compared by the detector cause the output relay to activate. The contacts
of the output relay to when activated are used to indicate the presence or absence of material in the
vessel at the probe level.
TEMPERATURE MEASURING INSTRUMENTS
THERMOCOUPLE
The thermocouples are based on Thermo-electric effect is known as Seeback effect. A thermocouple
consists of a pair of dissimilar metal wires joined together at one end (sensing or hot junction) and
terminated at the other end (cold junction or reference), which is maintained at a known constant
temperature (reference temperature).When a temperature difference exists between the sensing junction
and reference junction an EMF is produced that causes the current to flow in the circuit. When the
reference junctions terminated by a meter, the meter indication will be proportional to the temperature
difference between the hot junction and the reference junction .
RESISTANCE THERMOMETER
Resistance thermometers, also called resistance temperature detectors or resistive thermal devices
(RTDs), are temperature sensors that exploit the predictable change in electrical resistance of some
materials with changing temperature. As they are almost invariably made of platinum, they are often
called platinum resistance thermometers (PRTs).
TYPES
Figure 5.1 Film thermometers Figure 5.2 Wire-wound thermometers
Film thermometers
Film thermometer shave Film a layer of platinum on a substrate; the layer may be extremely thin,
thermometers perhaps one micrometer. Advantages of this type are relatively low cost and fast
response. Such devices have improved in performance although the different expansion rates of the
substrate and platinum give "strain gauge" effects and stability problems.

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Wire-wound thermometers
It can have greater accuracy, especially for wide temperature ranges. The coil diameter provides a
compromise between mechanical stability and allowing expansion of the wire to minimize strain and
consequential drift.
FUNCTION OF RTD
Resistance thermometers are constructed in a number of forms and offer greater stability, accuracy and
repeatability in some cases than thermocouples. While thermocouples use the Seebeck effect to generate
a voltage, resistance thermometers use electrical resistance and require a power source to operate. The
resistance ideally varies linearly with temperature. Resistance thermometers require a small current to be
passed through in order to determine the resistance. The two most common ways of measuring industrial
temperatures are with resistance temperature detectors (RTDs) and thermocouples. Selection criteria: -
Temperature, time, size, and overall accuracy.
KILN SHELL TEMPRATURE SCANNER
It is used for precise evaluation of the refractory's condition at all times. Evan if a single brick falls out
its location can be identified as a hot spot. It uses principles of non-contact temperature measurement. It
measures an object naturally emitted infrared radiation to determine its temperature. Infrared radiation
enters through a sensor window. A mirror rotating at 19.6 Hz receives infrared energy and reflects it on
to a lens, which focuses it on to a thermo electrically cooled detector. The detector receives energy from
the target for every 90 degrees of rotation of the mirror. Rest remaining 270 degrees of rotation are used
to self calibrate the instrument by reflecting infrared energy of two internal temperature indicators on to
the detector. The incoming signal is sampled at 20 kHz, converted from analog to digital and translated
by an internal microprocessor into temperature. For every rotation of mirror 256 measured values are
possible which can be averaged to 128 or 64measured signals. For data transmission an RS232 interface
with switchable baud rate is available and allows transmission of pre-processed data to a PC.
WEIGH FEEDER
As the name suggests it feeds material to the next process while weighing the material in proper
quantity. It is just like any conveyor belt but the belt speed is varied by weighing the material so as the
feed to the next process remains constant. The material on the belt is weighed by load cell under the belt
and the speed is varied by the speed control of dc motor. The signal from the load cell and speed
(measured by Tachometer) are multiplied in microprocessor card. The resultant shows the feed in TPH.
Further this TPH is compared by a set point given externally.
Now the microprocessor controller generates the error which is amplified and given to the Thyristor
controller, which controls the power fed to the DC motor which in accordance varies the speed of the
belt with the gear box and hence control the feed.

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INPUT, OUTPUT & MARKER
These are one bit variable that can have LOW or HIGH status. Inputs are signal from outside
to the control program, and outputs are signal from the control program to the external system. Markers
are internal variable and serve as memory.
within the control system. They are available outside the control system when they have been copied
onto outputs.
BELT WEIGHER
It is a system used to measure the feed of material to any m/c through belt conveyor. We are using it in
many location. In Raw mill it is being used.
PRINCIPLE OF OPERATION
Mass of material flowing on BC is sensed by load cells. Load cells are located under the belt in such a
way that the force acting on the load cell is equal to amount of material on the 1/2 meter of the belt,
hence it is represented in Kg/m. The belt speed is sensed by a speed transducer which is calibrated to
give belt speed in m/sec. The integration of belt loading and belt speed will give you total material,
whereas multiplication of two gives instantaneous flow rate in Kgs/sec. Various indicators totalizers,
alarms and control signals can be generated from flow rate signal.
Flow rate = Belt loading*Belt speed = Kg/m*m/sec = Kg/sec
Flow rate in tones/hours = Kg/sec*(3600/1000)
Total material conveyed= Int. of (f/v) dt from 0 to l
f = Belt loadingl = distance between rollers
v = belt speed It comprises of following
FIG.:- CONVEYOR BELT

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Conclusion
The practical training has proved to be quite fruitful. It provided me to encounter with such huge
machines and mechanisms. It has allowed me an opportunity to get an exposure of practical aspects and
their implementation to theoretical fundamentals.
I became familiarize with the practical engineering work in various disciplines and methods of
engineering practice. This will help me improving my performance in theory classes by introducing to
the practical work. It helped me to know my strengths and weaknesses so that I can improve my skills
and overcome my limitations by taking appropriate measures I was exposed to real work situations and I
learned how to equip them with the necessary skills so that I would be ready for the job when I’ll be
graduated.
The architecture of the plant, the way various units are linked, the way of working in plant and how
everything is controlled make me realize that engineering is not just learning the structured description
and working of various machines but the greater part of planning management.

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