bhel
DESCRIPTION
bhel jhansi training repoartTRANSCRIPT
SUMMER TRAINING
Project Report
On
DRY TYPE TRANSFORMER
SUBMITTED TO PROJECT MANAGER
Mr. Dhruva Bhargav Mr. H.K. Sharma
G.M. (HRD) Sr. Manager
D.T.T & Bay 8
SUBMITTED BY
ASHISH VERMA
DEPARTMENT OF ELECTRICAL ENGINEERING
MAHARANA PRATAP ENGINEERING COLLEGE, KANPUR[2010 – 2011]
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ACKNOWLEDGEMENT
Doing this project was a great experience for me, so I would like to express my gratitude to all those people who helped me during this project.
I am thankful to BHEL Jhansi for giving me the opportunity to do this project. I am thankful to my project guide Mr. H.K. Sharma (Sr. manager D.T.T &Bay 8) and technical staff which has shown a great interest in helping me to understand the functioning of various machineries. I am also thankful to numerous BHEL engineers who helped me in understanding the workings of their respective departments.
I would also like to thank all my fellow trainees who have been a constant source of encouragement and inspiration during my training period. At last I would thank my family for giving their whole hearted support in preparing this project.
ASHISH VERMA
B.TECH third year
(Electrical Engineering)
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CONTENTS
BHEL Jhansi 1
Brief introduction
Manufacturing Unit of BHE 2
Product Profile 3
BHEL Objectives 5
Achievement OF BHEL 12
Rotation Report 14
Dry Type Transformer 23
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BHEL JHANSI
Brief Introduction
By the end of 5 year plan it was envisaged by the planning commission that the demand for
power transformer would rise in coming year. Anticipating the country’s requirement BHEL
decided to set up a new plant, which would manufacture power transformer and other type of
transformer in addition to the capacity available in BHEL Bhopal. The Bhopal plant was
engaged in manufacturing transformer of large rating and Jhansi unit will focus on power
transformer up to 50 KV, 132 KV class & other transformer like instrument transformers,
traction transformer for railway etc.
The unit of Jhansi was established around 14 km from the city on N.H. NO. 26 on Jhansi
Lalitpur road in 1974 with an investigated cost of Rs 16.22Crores inclusive of Rs 2.10Carores
for township. It is called second generation plant of BHEL. Its foundation was laid by late Mrs.
Indira Gandhi on 9 Jan 1974. The commercial production of the unit began with an output of 53
lakes, since than there has been no looking back for BHEL Jhansi.
The plant of BHEL was equipped with the most modern manufacturing, processing and testing
facilities for the manufacturing power, special transformer and instrument transformers, diesel
Locomotives, Ac/Dc locomotives.
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The raw materials that are used for manufacturing goes through lab tests in addition with strict
quality checks at various stages during the production. Up till 1987 BHEL Jhansi was engaged in
manufacturing transformers and than in 1987-88 BHEL progressed a step further by undertaking
the production of the locomotives and subsequently it is manufacturing Ac/Dc locomotives also.
MANUFACTURING UNIT OF BHEL
First Generation Units
BHOPAL Heavy Electrical Plant
HARDWAR Heavy Electrical Equipment Plant
HYDERABAD Heavy Electrical Power Equipment Plant
TIRUCHY High Pressure Boiler Plant
Second Generation Units
JHANSI Transformer and Locomotive Plant
HARDWAR Central Foundry and Forge Plant
TIRUCHY Seamless Steel Tube Plant
Unit Through Acquisition and Merger
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BANGALORE Electronic Division
Electro Porcelain Division
New Manufacturing Units
RANIPAT Boiler Auxiliaries Plant
JAGDISHPUR Insulator Plant
RUDRAPUR Component and Fabrication Plant
BANGALORE Industrial System Group
PRODUCT PROFILE
Products Rating
1. Power Transformer up to 400 KV 315 MVA
2. Rectifier Transformer up to 132 KV 120KVA
3. Furnace Transformer up to 33 KV 60 MVA
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4. Voltage Transformer up to 220 KV
5. Current Transformer up to 400 KV
6. Traction transformer
(a) Single Phase Freight Loco. up to 25 KV 5400 KVA
(b) Three Phase Freight Loco up to 25 KV 7475 KVA
7. Transformer For ACEMU up to 25 KV 1550 KVA
8. Cast Resin Dry type Transformer up to 33 KV 15 MVA
LOCOMOTIVES
1. Diesel Locomotives
2. AC/DC Locomotives
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3. Special purpose wagons
4. Rail cum road vehicle
5. Synchrolift
BHEL OBJECTIVES
A dynamic organization is one which keeps its aim high, adopts itself quickly to changing
environment, so we are in BHEL. The objectives of the company have been redefined in the
corporate plane for 90’s.
Busyness Mission
To maintain a leading position as supplier of quality equipments, system and services in the field
of conversion, transmission, utilization, and conversation of energy for application in the area of
electric power, transportation oil and gas exploration and industries. To utilize company’s
capability and resources to expand busyness in to allied area an priority sector of economy like
defense, communication and electronics.
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Growth
To ensure a steady growth by enhancing the competitive edge of BHEL in existing busyness,
new area and international market so as to fulfill national expectation from BHEL.
Profitability
To ensure a reasonable and adequate return on capital employed, primarily through
improvements in operation, efficiency, capacity utilization & productivity and to generate
adequate internal resources to finance the company’s growth.
Focus
To built a high degree of customer confidence by providing increased value of his money
through international standards of product quality performance and superior customer service.
People Orientation
To enable each employee to achieve his potential, improve his capabilities, understand is role
and responsibilities and participate and contribute to the growth and success of the company.
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Technology
To achieve technological excellence in operation of indigenous technologies and efficient
absorption and adoption of imparted technologies to suit business.
Image
To fulfill the expectations, which stack holders like government as owner employee, customer
and the country at large have from BHEL.
Power
Provides a gamut of equipment for thermal, hydro and nuclear plants. Range includes product
and system for power generation, transmission and utilization.
Highlights
1. Thermal
Maximum size supplied 500 MW with the capability to manufacture 1000 MW units.
Already over 250 sets contracted.
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2. Nuclear
235 MW sets supplied, 500 MW sets under manufacture.
3. Gas
Maximum size supplied 150 MW(ISO), capability to manufacture 240 MW(ISO)
4. Hydro
Maximum size supplied 165 MW, 250 MW units under manufacture.
Major Client
State electricity boards/Power corporations
NTPC
National Hydro Electricity Power Corporation
Nuclear Power Corporation
Damodar Valley Corporation etc.
Transmission
BHEL is manufacturing transmission equipment for all voltage rating including 400 KV class
transformers, switch gears, control and relay panel, insulator, capacitor and other equipment.
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Highlights
1. System
HVDC
Compensator Series and Shunt(SVC)
Substation
Power System analysis
SCADA
2. Products
Transformer (oil type and dry type)
Switch gear (oil, vacuum, & SF medium )
GIS
Capacitor
CT/PT/CVT
Reactor
3. Voltages
AC 400 to 800 KV under development
DC up to 500 KV
Major Clients
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SEV’s
West Bengal power development Corp ltd
Tenughat Viduat Nigam Ltd
NTPC
Rashtriya Ispat Nigam
National Fertilizers Ltd, etc
Industry
Offers a comprehensive range of electrical, electronic and mechanical equipment for a host of
industries like fertilizer, petrochemical, refineries, paper, sugar, rubber, cement, coal, steel,
aluminum and mining.
Highlight
1. Product & system
Turbo set
Diesel generator sets
Boiler
Steam generator
Pump
Seamless steel tube
Drives and controls
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C & I, etc
2. Application
Fertilizer
Petrochemical
Coal
Steel
Aluminum
Mining etc.
Major Clients
National Aluminum Corporation
Hindustan Fertilizers & Chemicals Ltd
Hindustan Paper Corporation
Hindustan sugar, Mysore sugar
Indian Oil Corporation
Defense Ministry
Indian Petro Chemicals Ltd
Reliance Industries, etc.
ACHIVEMENT OF BHEL
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BHEL has
1. Installed equipment for over 90,000 MW of generation fro utilization, captive and
industrial user.
2. Supplied over 2, 25,000 MVA transformer capacity and other equipment operating
and transmission and distribution network AC/dc up to 400 KV (AC/DC).
3. Supplied over 25000 motors with drive control system to power projects,
petrochemicals, refineries, steel, aluminum, fertilizer, cements plants etc.
4. Supplied reaction electrics and AC/DC locos to power over 12000 Kms railway
networks.
5. Supplied over 1million valves to power plants and other industries.
BHEL vision is to become a world class engineering enterprise, committed to enhancing
stakeholder value. The company is striving to give shape to its aspiration and fulfill the
expectations of the country to become a global presence:-
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Vision:
“A world class engineering enterprise committed to enhance stakeholder values.”
Mission
“To be an Indian multinational engineering providing total business solution through quality
product system and services in the field of energy, transportation, industry, infrastructure and
other potential area.
Values
Ensure speed of response.
Foster learning, creativity and team work.
Respect for dignity and potential of individuals
Loyalty and pride in company
Zeal for the change.
Zeal to excel.
Integrity and fairness in all matters.
Strict adherence to commitments.
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ROTATION REPORT
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TRANSFORMER MANUFACTURING
1. Inventory
It is the section of storage of raw material.
2. Fabrication
Fabrication is nothing but production. It comprises of three bays:
Bay 0:
It is basically a machine / preparation shop. This section has following machines:
1. Pacific Hydraulic Shear & pressure: Hydraulically operated machine to cut to sheet of
different thickness. It contain pressure holder which is used to flatten the sheet.
2. CNC (Computerized Numerical control) Flame cutting machine: Used to cut
complicated shaft item using OXY-ACETYLENE flame. Maximum 6 torches are
used in it. Cutting is done on the basis of computer programming.
3. Rolling Machine: used for making cylindrical shape from a sheet.
4. Bending Machine: Hydraulically operated machine used to bend the job.
5. Hydraulic power press: Has the capacity of 100 tons used to flatten the object.
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6. Nibbling Machine: used to do various tasks like straight cutting, circle cutting,
nibbling, slot cutting, circular and square punching.
7. Hydraulic Guillotine Shear: It is to cut the sheet which has maximum cross section
area of (3200*13 sq.mm).
8. Butler machine: used for facing, tapering, & slot cutting.
9. Plasma Cutting Machine: used for non ferrous metal.
Bay 1:
It is an assembly shop where different part of tank comes from bay 0. Hear welding
processes are used for assembly, after which a rough surface is obtained and is
eliminated by grinding. Grinding operates at 1200 RPM.
Bay 2:
It is assembly shop dealing with making different objects like.
Tank Assembly
Tank cover assembly
End frame assembly
Cross feed assembly
Core Clamp assembly
Pin & pad assembly
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Before assembly, short blasting is done on different part of jobs to clean the
surface before painting.
After assembly some tests are done as non-destructive tests like.
1. Ultrasonic Test: To detect the winding fault on CRO. At the fault place high amplitude
waves are obtain.
2. Die Penetration Test: Red solution is put at the welding and then cleaned. After some
time white solution is put. Appearance of red spot indicates a fault at the welding.
3. Magnetic crack detection: magnetic field is created and then iron powder is put on the
welding. Sticking of the iron powder in the welding indicates the fault.
4. X-Ray Test: It is same as human testing and a fault is seen in X-ray.
5. Air / Vacuum Test: the air is filled inside the body of transformer, than soap solution is
produced outside the body. If the holes appear, it is indicate the fault.
Bay 3:
The bay has basically three sections.
Machine Sections: To operation to form small components of power and traction
transformer are done is this section. The shop consists of following machines.
CENTRAL LATHE: It consist one tail stock, head stock. Lower part of tail stock
is fixed and tail stock spindle is moving. On this machine is facing, turning and
threading is done.
TURRET LATHE: Its function is same as central lathe machine but it is used for
mass production. Here turret head is used in presence of tail stock because turret
head contains many tailstocks around six.
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CAPSTAN LATHE: It is belt driven.
RADIAL ARM DRILLING MACHINE: Used for drilling and boring.
HORIZONTAL BORING MACHINE: It is computerized and used for making
bore, facing etc.
MILLING MACHINE:
a) HORIZONTAL MILLING MACHINE: Used for making gear and cutting
operations.
b) VERTICAL MILLING MACHINE: The machine does facing, slot cutting
and T-slot cutting.
COPPER SECTION:
Tube slitting Machine: used for cutting the tube along its length and across the
diameter.
HYDRAULIC SHEARING MACHINE: It is hydraulically operated and its blade
has V-shape and a thickness 15 mm.
WATER COOLED BRAZING MACHINE: It contains two carbon brushes. The
sheet is put along with sulfas sheet and the carbon brushes are heated. A lap joint
is formed between the sheets as the sulfas sheets melts.
LINCING BELT MACHINE: It creates a smooth surface.
SOLDER POT MACHINE: It has a pot that contains solder. Solder has
composition of 60 % Zn and 40 % Pb.
3. TOOLING MACHING: In this section the servicing of tools is done.
Blade sharp machine
Mini surface grinding Machine(used for grinding purpose)
Tool and surface grinding Machine(used to grind the tool)
Drill grinding Machine (to grid the drills)
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Bay 4:It is the winding, coil and moulds section.
TYPES OF WINDING
a) Reverse section winding
b) Helical winding
c) Spiral winding
d) Interleaved winding
e) Half section winding
The type of winding depends upon the job requirement. Also, the width and thickness of conductors designed and decided by design department.
TYPES OF COIL
1. Low voltage coil
2. High voltage coil
3. Tertiary coil
4. Tap coil
THE MOULDS ARE OF FOLLING TYPES
1. Belly type
2. Link type
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3. Cone type
Bay 5:
It is lamination and punching shop. The lamination used in power, dry and ESP transformer etc. for making core is cut in this section. CRGO (cold rolled grain oriented) silicon steel is used for lamination, which is imported in India from Japan, U.K and Germany. It is available in 0.27&0.28 mm.
For the purpose of cutting and punching the core three machines are installed in the shop.
Slitting machine (used to cut CRGO sheets in different width)
CNC cropping line pneumatic
CNC cropping line hydraulic
Bay 6:
Single phase transformer for AC locomotives is assembled in this section. In this bay core winding and all the assembly of testing of traction transformer is done.
The tap changer of rectifier transformer is also assembled in this bay.
Bay 7:
This is the insulation shop. Various type of insulation are:
AWWW: all wood water washed press paper. The paper is 0.2-0.5 mm thick cellulose paper is bound on conductor for insulation.
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Pre-Compressed Board: this is widely used for general insulation and separation of conductors in the form of blocks.
Press Board: this is used for separation of coil e.g. LV from HV. It is up to 38 mm thick. Fiber Glass: this is resin material and is used in fire prone area. Bakelite Gasket: used for protection against leakage. Silicon Rubber Sheet: It is used for dry type transformer.
Machine used for shaping the insulation material are:
1. Cylindrical machine2. Circular cutting machine3. Bending machine4. Punching press machine5. Drilling machine6. Guillotine machine7. Bench saw8. Jig saw9. Circular saw10. Lansing machine
Bay 8:
It is the instrument transformer and ESP transformer manufacturing section.
1. Instrument transformer: used for measuring the AC voltage and currents of high ratings.a) Current transformer: it is a step down transformer. The body is divided in to
three parts – top chamber, bushing, bottom chamber. Top chamber is the cylindrical tank of mild steel. It has terminal for connection of HV coil. It also has oil window to indicate the oil level. Below it is bushing which houses the winding and also act as insulator. It has several folds or rain sheds to provide specific electric field distribution and long leakage path. Some bushings are cylindrical while modern ones are conical, as the amount of oil porcelain used is reduced without any undesirable effects. Bottom chamber houses the secondary winding. There is also a connection box to which the connection of low voltage coil is made.
b) Voltage Transformer: It is also an step down transformer and outer construction is same as that of CT. the difference is only in winding.
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2. ESP Transformer: Electrostatic precipitator transformer is used for environmental applications. It is used to filter suspended charged particles in the chimneys of the industries particularly power plants and cement industries. It is a single phase step up transformer. An AC reactor is connected in series with primary coil. The output must be DC which is obtained by rectifying the AC using bridge rectifier. A radiofrequency choke in connected in series with DC output for the protection of secondary circuit and the filter circuit. The output is choose negative because the particles are the positively charged. The dc output from the secondary is given to the set of plates arrange one after other. Positively charged impurity particles sticks to the plates and are jerked off. For this a network of plates has to be setup all across the plant. This process is very costly in comparison to the transformer cost. A relevant is also provided to prevent the transformer from bursting. If higher pressure develop inside it.
An oil temperature indicator and secondary supply spark detector are also provided. One side of the transformer output is taken and the other side has a marshalling box, which is the control box of the transformer.
Bay 9:
In this bay power transformer are assembled after taken sub assemblies from Bays (0 to 8).
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DRY TYPE TRANSFORMER
The dry type transformers manufactured in BHEL consist of high voltage and low voltage
windings made up of copper conductors which are completely encapsulated and cost under
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vacuum. The casting is done using liquid epoxy resin, rain forced by fiber glass insulation of
class F to form a very robust and very maintenance free insulation system for winding. The HV
or LV coils are cast separately to form individual solid cylinder.
The core is made from lamination of CRGOS. The core edges are coats with special resin as
protection against rusting.
The transformers are provided with suitable protective steel enclosures. The enclosure are
provided with louvers covered with wire mesh to allow free circulation of clean natural air inside
the enclosure of air natural cooling.
For thermal protection, RTD PT-100 sensors are embedded in the coils to do the temperature
monitoring of the transformer. These sensors feed signal to the temperature scanner unit for
continuous monitoring of winding.
The temperature scanning unit is provided with auxiliary relays, one for alarm and one for trip.
Alarm relay should be wired with suitably located alarm to give an indication if transformer
winding temperature is exceeded. The trip relay should be wired with HT circuit breaker to trip
the supply in case the temperature rises beyond the safe limit because of any fault which may
damage the transformer permanently. The control wiring is terminated on the terminal blocks
located inside the junction box on the enclosure. The HT and LT side are terminated suitably for
the connections of the cables. A separate earthing flat from LV neutral is brought out for the
provision of system earthing. In addition of the enclosures is provided with suitable earthing
pads for body earthing.
MANUFACTURING PROCESS
The dry cast iron resin transformers are manufactured using copper conductors for winding and
glass & epoxy resin for insulation. The process is as follows:
1. WINDING: Copper conductors make both LV and HV winding over steel formers.
The winding are densely embedded in glass fibers and are tightly by glass tapes. LV
windings are generally helical in shape and HV winding are made spiral or disk type.
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Both the windings are made separately except for very small rating where HV and LV are
made together because of small diameter.
After the winding is complete the bound coils are placed in separate steel moulds and are
pre dried in heating oven or heated vacuum chamber before casting.
2. CASTING: Dried moulds containing in vacuum chamber for casting. Casting is done
by utilizing the unique properties offered by pure liquid epoxy system. Various
constituents of epoxy resin are first heated in separate vacuum post to eliminate dissolved
gases and moisture. Then these are mixed in precise proportion as per the requirements
and supplied to dried windings placed inside moulds under high vacuum to give void
less embedment of winding by epoxy. The epoxy is slowly absorbed by the fiberglass
reinforcement provided during winding to from a dense fibrous mass. When the moulds
filled by liquid epoxy ensuring complete void less encapsulation they are taken further
for processing in post curing ovens. The whole process control by computer carried out
automatically as high degree of accuracy is required.
The epoxy reinforced by the glass, after curing form a solid dense mass, which
encapsulated the copper winding. The process gives the winding better mechanical
strength than any other form of manufacturing process and at the same time epoxy system
employed provides the high dielectric strength.
3. CUTTING AND DRESSING: After the coils are cured they are taken out of
moulds. The cured and dry coils are hard enough to carry out any matching. Rather the
hardness of fiber glass reinforced epoxy resin cast coil require special tools and blades
and for matching as ordinary steel tools used for cutting steel and other metals wears out
quickly.
Excess epoxy deposited on the top of coil is swan of to require dimension and sharpen
edges are removed and smoothened by milling or grinding. Touching up paints is applied
to coil if required and finished coils are tested and send to assembly.
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4. ASSEMBLY OF TRANSFORMER: The finished cast resin coils are placed in
core by removing the top yoke of pre-assembled core. The top yoke is replaced after
pacing HV and LV coils. The coils are supported at the top and bottom by end blocks.
The coil and windings are then clamp and tightly together by galvanized steel channels
and terminal gear assembly is carried out for the required HV and LV terminations.
Special class F resin is applied on the exposed area of core as a protection against rusting.
The core and coil assembly is then mounted on the roller base. After fixing bidirectional
rollers, the core and coil assembly along with roller is placed inside the enclosures. The
enclosures are bolted to core and assembly. Necessary winding is carried out and all the
fittings and accessories are mounted on the transformer.
The finished transformer is now ready for testing and maintenance free service.
CHARECTERSTICS & FEATURES
1. MAINTENANCE FREE NATURE OF COST RESIN DTT: These are
virtually maintenance free under most severe topical, dusty and corrosive
environment.
No drying of transformer required after duration of shut down as epoxy cast coil are
non hygroscopic and do not absorb moisture. Infect experiments has shown that
transformer continue to work at rated voltages even with coils sprayed with water.
This eliminates the need of readjustment and retensioning of windings in DTT.
Similarly no control and checking of oil are required. This leads to considerable
savings in expenditure required for maintenance and periodic recalculation of oil.
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2. IMMEDIAT SWITCH ON: Because of non hygroscopic insulation system the
transformer can be switched on without pre-drying even after long periods of shut
down.
3. SELF EXTINGUISHING AND INFLAMMABLE: The insulation system
of fiber epoxy provides transformer coil with self extinguishing properties. This is
most important properties of cast resin transformer and makes possible their use in
indoor condition.
4. IMPULSE STRENGTH: The winding are cast using liquid epoxy under
vacuum giving void less encapsulation with high impulse strength. The HV coil are
made by employing are special winding arrangement to provide BIL level same as
that of oil filled up to a level of 170 KVP for 33KV class transformer.
5. SHORT CIRCUIT WITH STAND CAPABILITY: The glass epoxy
laminate insulation provides windings with most dynamic short circuit strength which
exceeds that of oil filled or conventional DTT.
Infect three same material is used in other commercial products like skis, tension
chain and tools where full advantage of mechanical strength is taken.
6. RESISTENCE AGAINST TEMPRATURE FLUCHUATION: The
insulation system withstands even the most extreme temperature fluctuation. Is
service temperature of class F i.e. 155C can be safely reached and transformer can
operate at this temperature continuously.
7. SPACE SAVING: The cast resin transformers have generally small dimensions
and are also less in weight. This reduces transportation and installation casts for
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substation. Also no special construction like brick laid rooms are requires for indoor
installation. The transformer in steel housing can be located directly adjacent to other
switchgear control cubicles. This provides compact design for substation.
8. HIGH OVER LOAD CAPACITY: Due to high time constant of dry type
winding the cast coil can be overloaded for short duration for higher overloads than
oil immerged transformer. The transformer especially suitable for rectifier and
convertor duties because of it.
9. LOWER LOSSES AND HIGHER EFFICIENCY: For DTT above 1000
KVA the overall losses are less compared to that of oil filled transformer of same
rating. This result in direct saving I form of loss capitalization and higher operating
efficiencies.
10. INCREASE IN PERFORMANCE BY FORCED COOLING: The
capacity of cast resin transformer can be increased up to 40% by forced cooling. Two
fans are provided on one side of transformer with duct extending directly below the
coils to cool the windings. The fans are controlled by the temperature and are
switched of as soon as the temperature goes below a certain specified temperature.
However continuous forced air operation is not recommended as the losses and the
noise generated by the fan makes the operation unattractive.
11. HIGHER RELIABILITY: The cast resin transformer have a very low failure
rate of less than one in one thousand and have a life of 20 years compared to oil filled
transformer having a average life span of 3 to 4 years only. This coupled with
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maintenance free nature and decentralized power distribution system provide an
economical alternative to oil filled transformers over a period of time.
APPLICATION:
Power Plants
Static Excitation Equipments
Steel Rolling mills
Oil Rigs and Refineries
Under Ground Substation and Mining
Chemical and Fertilizer Plant
Metro Railway
High Rise Buildings
Cinema Halls & Hospitals
PRODUCT RANGE:
Rating (KVA) – 10-10,000 KVA
Rated Voltage - up to 33 KV
BIL - up to 170 KVP
Insulation Class - F
Frequency - 50 to 60 Hz
Winding Arrangement - Dual Ratio & 3 windings
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Voltage Variation - Off circuit
CONSTRUCTIONAL FEATURES:
1. CORE: Cold Rolled Grain Oriented Silicon Steel (CRGOS).
2. WINDING: Electrolyte grade copper with high quality fiber glass
3. RASIN ENCAPSULATION: Internationally proven system of epoxy resin casting
4. ENCLOSURE: 2mm thick CRC steel, Ventilated enclosure
5. FITTING: Standard fitting such as lifting lugs, bidirectional flat rollers or skids, etc
6. PROTECTION: Thermal Protection by a system of thermistors embedded on the top of
the LV winding
ENGINEERING AND R&D CAPABILITIES:
Designs and drawings are made by hand/computer
Mainframe computers and CAD work stations are available
Technology is based on M/S may & Christie Germany (now knows Skoda Ltd ) who are
pioneer in world for manufacture of dry type cast resin transformers for the last 30
years.
For R&D work, BHEL corporate research and development center has been sat up in
Hyderabad.
MANUFACTURING FACILITIES:
Thin film design maker – manufactured by HEDRICH, Germany.
High vacuum casting chamber – manufactured by VPI, pune.
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Heating ovens – M/S THERMELEK, Bangalore
Coil winding machine
Coil cutting machine
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