AN INDUSTRIAL TRAINING REPORT

ON

TURBINE MANUFACTURING at B.H.E.L., Haridwar

SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FORTHE AWARD OF THE DEGREE OF

BACHELOR OF TECHNOLOGYIN

MECHANICAL ENGINEERING

ByABHISHEK SINGH

Submitted ToMr. SUSHIL KUMAR RAWAT

DEPARTMENT OF MECHANICAL ENGINEERING RAJDHANI INSTITUTE OF TECHNOLOG MANAGEMENT

ACKNOWLEDGEMENT

We take this opportunity to thank the Industrial Training Co-Ordinator of Mechanical

Engineering Department for allowing us to work on such an interesting & informative topic. We

are highly indebted to our project guide MR. SUSHIL KUMAR RAWAT Sir for his guidance

& words of wisdom. He always showed us the right direction during the course of this project

work

I am also grateful to the management of Bharat Heavy Electricals Limited (B.H.E.L.),

Haridwar for permitting me to have training during 9th June to 24st July, 2016.

We worked as a team and saw ups and downs which are part of any project work. But in the end

it was their Guidance and my team work which made this project possible. Last but not the least

we would also like to thank all our teachers & friends for their constructive criticism given in

right spirit.

Abhishek singh 7th Semester, B.Tech.

Department of Mechanical Engineering Rajdhani institute of technology and management

ABSTRACT

In the era of Mechanical Engineering, Turbine, A Prime Mover ( Which uses the Raw Energy of a substance and converts it to Mechanical Energy) is a well known Machine most useful in the the field of Power Generation. This Mechanical energy is used in running an Electric Generator which is directly coupled to the shaft of turbine. From this Electric Generator, we get electric Power which can be transmitted over long distances by means of transmission lines and transmission towers.

In my Industrial Training in B.H.E.L., Haridwar I go through all sections in Turbine Manufacturing. First management team told me about the history of industry, Area, Capacity, Machines installed & Facilities in the Industry.

After that they told about the Steam Turbine its types , parts like Blades, Casing, Rotor etc. Then they told full explanation of constructional features and procedure along with equipement used. Before telling about the machines used in Manufacturing of Blade, they told about the safety precautions, Step by Step arrangement of machines in the block with a well defined proper format. They also told the material of blade for a particular desire, types of Blades, Operations performed on Blades, their New Blade Shop less with Advance Technology like CNC Shaping Machine.

I would like to express my deep sense of Gratitude and thanks to Mr. SUSHIL KUMAR RAWAT(AGM) our in charge of training in Turbine Block in B.H.E.L., Haridwar. Without the wise counsel and able guidance, it would have been impossible to complete the report in this manner. Finally, I am indebted to all who so ever have contributed in this report and friendly stay at Bharat Heavy Electricals Limited (BHEL).

INDEX

ABSTRACT i

ACKNOWLEDGEMENT iiCERTIFICATE iii

Sr. No. Topic Page no.INTRODUCTION 1

1. BHEL 2-3

1.1 OVERVIEW 3

1.5 BHEL UNITS 33

1.6 BHEL HARIDWAR 3-41.6.1 LOCATION 41.6.2 ADDRESS 4-51.6.3 AREA 51.6.4 UNITS 5

5-6

Sr. No.

Topic Page no.

1.6.5 HEEP PRODUCT PROFILE

12-13

2. STEAM TURBINE 142.1 INTRODUCTION 14-152.2 ADVANTAGES 162.3 DISADVANTAGES 162.4 STEAM TURBINE THE MAINSATY OF BHEL 16

3. TYPES OF STEAM TURBINE 173.1 THE IMPULSE TURBINE

17

3.2 THE IMPULSE TUBINE PRINCIPLE 173.3 THE REACTION PRINCIPLE 18

4. TURBINE PARTS 184.1 TURBINE BLADES 18-194.2 TURBINE CASING 194.3 TURBINE ROTORS 19-20

5. CONSTRUCTIONAL FEATURES OF BLADE

20

5.1 H.P. BLADE PROFILES 20-215.2 CLASSIFICATION OF PROFILES

21-22

5.3 H.P. BLADE ROOTS 22-235.4 L.P. BLADE PROFIES 235.5 L.P. BLADE ROOTS 235.6 DYNAMICS OF BLADE 23-255.7 BLADING MATERIALS 25

6. BLOCK-3 LAYOUT

CLASSIFICATION OF BLOCK-3

BLADE SHOP9.1 TYPES OF BLADES9.2 OPERATIONS PERFORMED ON BLADES

7.

8. 9.3 MACHINING OF BLADES9.4 NEW BLADE SHOP

9.CONCLUSION

FIGURE INDEX

Sr. No. Topic1. SECTIONAL VIEW OF STEAM TURBINE2. FLOW DIAGRAM OF A STEAM TURBINE

3. HIGH PRESSURE BLADE PROFILE 4. OVERSPEED AND VACCUM BALANCING WHEEL 5. STEAM TURBINE CASING AND ROTORS IN ASSEMBLING

AREA 6. CNC ROTOR TURNING LATHE 7. TYPES OF BLADES 8. SCHMETIC DIAGRAM OF A CNC MACHINE 9. CNC SHAPING MACHINE

INTRODUCTION

BHEL is the largest engineering and manufacturing enterprise in India in the energy related infrastructure sector today. BHEL was established more than 40 years ago when its first plant was setup in Bhopal ushering in the indigenous Heavy Electrical Equipment Industry in India a dream which has been more than realized with a well recognized track record of performance it has been earning profits continuously since1971-72.

BHEL caters to core sectors of the Indian Economy viz., Power Generation's & Transmission, Industry, Transportation, Telecommunication, Renewable Energy, Defense, etc. The wide network of BHEL's 14 manufacturing division, four power Sector regional centers, over 150 project sites, eight service centers and 18 regional offices, enables the Company to promptly serve its customers and provide them with suitable products, systems and services – efficiently and at competitive prices. BHEL has already attained ISO 9000 certification for quality management, and ISO 14001certification for environment management.

The company’s inherent potential coupled with its strong performance make this one of the “NAVRATNAS”, which is supported by the government in their endeavor to become future global players.

B.H.E.L.

1.1. OVERVIEW

Bharat Heavy Electricals Limited (B.H.E.L.) is the largest engineering and manufacturing enterprise in India. BHEL caters to core sectors of the Indian Economy viz., Power Generation's & Transmission, Industry, Transportation, Telecommunication, Renewable Energy, Defense and many more.

Established in 1960s under the Indo-Soviet Agreements of 1959 and 1960 in the area of Scientific, Technical and Industrial Cooperation.

BHEL has its setup spread all over India namely New Delhi, Gurgaon, Haridwar, Rudrapur, Jhansi, Bhopal, Hyderabad, Jagdishpur , Tiruchirapalli, Bangalore and many more.

Over 65% of power generated in India comes from BHEL-supplied equipment.Overall it has installed power equipment for over 90,000 MW.

BHEL's Investment in R&D is amongst the largest in the corporate sector in India. Net Profit of the company in the year 2011-2012 was recorded as 6868crore having a high of 21.2% in comparison to last year.

BHEL has already attained ISO 9000 certification for quality management, and ISO 14001 certification for environment management.

It is one of India's nine largest Public Sector Undertakings or PSUs, known as the NAVRATNAS or 'The Nine Jewels’.

The power plant equipment manufactured by BHEL is based on contemporary technology comparable to the best in the world.

The wide network of BHEL's 14 manufacturing divisions, 4 Power Sector regional centre, over 100 project sites, 8 Service Centre and 18 regional offices, enables the Company to promptly serve its customers and provide them with suitable products, systems and services efficiently.

.

1.5 BHEL UNITS

UNIT TYPE PRODUCT

1. Bhopal Heavy Electrical Part Steam Turbines, Turbo Generators, HydroSets,Switch Gear Controllers

2. Haridwar Hydro Turbines, Steam Turbines, GasTurbines, Turbo Generators, Heavy Castings

HEEP Heavy Electrical Equipement and Forging, Control Panels, Light Aircrafts,Plant Electrical Machines.

CFFP Central Foundry Forge Plant

3. Hyderabad Industrial Turbo-Sets, Compressor Pumpsand Heaters, Bow Mills, Heat Exchangers

HPEP Heavy Power Equipement Plant Oil Rings, Gas Turbines, Switch Gears,Power Generating Sets.

4. TrichySeamless Steel Tubes, Spiral Fin Welded

HPBP High Pressure Boiling Plant Tubes.5. Jhansi

Transformers, Diesel Shunt Less AC locosTP Transformer Plant and EC EMU.6. Banglore Energy Meters, Watt Meters, Control

Equipement, Capacitors, Photo Voltic Panels,EDN Electronics Division Simulator, Telecommunication System, Other

Advanced Microprocessor based ControlEPD Electro Porcelains Devision System, Insulator and Bushing, Ceramic

Liners7. Ranipet Electrostatic Precipitator, Air Pre-Heater,

Fans, Wind Electric Generators, DesalinationBAP Boiler Auxilary Plant Plants.

8. Goindwal Industrial Valves Plant Industrial Valves & Fabrication9. Jagdishpur High tension ceramic, Insulation Plates and

IP Insulator PlantBushings

10. Rudrapur Component Fabrication Plant Windmill, Solar Water Heating system11. Gurgaon Amorphous Silicon Solar Cell Solar Photovoltaic Cells, Solar Lanterns,

Plant. Chargers ,Solar clock

Table-1

1.6. BHEL HARIDWAR

1.6.1. LOCATION

It is situated in the foot hills of Shivalik range in Haridwar. The main administrative building is at a distance of about 8 km from Haridwar.

1.6.2. ADDRESS

Bharat Heavy Electrical Limited (BHEL)

Ranipur, Haridwar PIN- 249403

1.6.3. AREA

BHEL Haridwar consists of two manufacturing units, namely Heavy Electrical Equipment Plant (HEEP) and Central Foundry Forge Plant (CFFP), having area

HEEP area:- 8.45 sq km

CFFP area:- 1.0 sq km

The Heavy Electricals Equipment Plant (HEEP) located in Haridwar, is one of the major manufacturing plants of BHEL. The core business of HEEP includes design and manufacture of large steam and gas turbines, turbo generators, hydro turbines and generators, large AC/DC motors and so on.

Central Foundry Forge Plant (CFFP) is engaged in manufacture of Steel Castings:Up to 50 Tons per Piece Wt & Steel Forgings: Up to 55 Tons per Piece Wt.

1.6.4. UNITS

There are two units in BHEL Haridwar as followed:

1) Heavy Electrical Equipment Plant (HEEP)

2) Central Foundry Forge Plant (CFFP)

There are 8 Blocks in HEEP:

Blocks Work Performed In BlockI) Electrical Machine Turbo Generator, Generator Exciter , Motor (AC and DC)

II) Fabrication Large Size Fabricated Assemblies or Components

III) Turbines & Steam , Hydro Turbines, Gas turbines, Turbine Blade, Special Tooling.Auxilary

IV) Feeder Winding of Turbo ,Hydro Generators, Insulation for AC & DC Motors

V) Fabrication Fabricated Parts of Steam Turbine, Water Boxes, Storage Tank, HydroTurbine Parts

VI) Fabrication Fabricated Oil Tanks, Hollow Guide Blades, Rings, Stator Frames andStamping & Die Rotor Spindle, All Dies, Stamping for Generators and MotorManufacturing

VII) Wood Working Wooden Packing, Spacers

VIII) Heaters & LP heaters, Ejectors, Glands, Steam and Oil Coolers, Oil Tank, BearingCoolers Covers

Table-2

There are 3 Sections in CFFP:

Blocks Work Performed In Block1. Foundry Casting of Turbine Rotor, Casing and Francis Runner

2. Forging Forging of Small Rotor Parts

3. Machine Shop Turning, Boring, Parting off, Drilling etc.

Table -3

1.6.5. HEEP PRODUCT PROFILE

1. THERMAL SETS:

Steam turbines and generators up to 1000 MW capacity for utility and combined cycle applications

Capability to manufacture up to 1000 MW unit cycle.

2. GAS TURBINES:

Gas turbines for industry and utility application range 3 to 200 MW (ISO). Gas turbines based co-generation and combined cycle system.

3. HYDRO SETS:

Custom– built conventional hydro turbine of Kaplan, Francis and Pelton with matching generators up to 250 MW unit size.

Pump turbines with matching motor-generators. Mini / micro hydro sets. Spherical butterfly and rotary valves and auxiliaries for hydro station.

4. EQUIPMENT FOR NUCLEAR POWER PLANTS:

Turbines and generators up to 500MW unit size. Steam generator up to 500MW unit size. Re-heaters / Separators. Heat exchangers and pressure vessels.

5. ELECTRICAL MACHINES:

DC general purpose and rolling mill machines from 100 to 19000KW suitable for operation on voltage up to 1200V. These are provided with STDP, totally enclosed and duct ventilated enclosures.

DC auxiliary mill motors.

6. CONTROL PANEL:

Control panel for voltage up to 400KW and control desks for generating stations and EMV sub–stations.

7. CASTING AND FORGINGS:

Sophisticated heavy casting and forging of creep resistant alloy steels, stainless steel and other grades of alloy meeting stringent international specifications.

8. DEFENCE:

Naval guns with collaboration of Italy.

2. STEAM TURBINE

2.1 INTRODUCTION

A turbine is a device that converts chemical energy into mechanical energy.A turbine is a rotary engine that extracts energy from a fluid flow and converts it into useful work. The simplest turbines have one moving part, a rotor assembly, which is a shaft or drum with blades attached. Moving fluid acts on the blades, or the blades react to the flow, so that they move and impart rotational energy to the rotor.

Fig.1 Sectional View Of A Steam Turbine

In a steam turbine, the steam’s energy is extracted through the turbine and the steam leaves the turbine at a lower energy state. High pressure and temperature fluid at the inlet of the turbine exit as lower pressure and temperature fluid. The difference is energy converted by the turbine to mechanical rotational energy, less any aerodynamic and mechanical inefficiencies incurred in the process. Since the fluid is at a lower pressure at the exit of the turbine than at the inlet, it is common to say the fluid has been “expanded” across the turbine. Because of the expanding flow, higher volumetric flow occurs at the turbine exit (at least for compressible fluids) leading to the need for larger turbine exit areas than at the inlet.ORSteam turbine is such type of turbine where steam is used as working fluid. When steam is injected over the blades it rotates at a certain speed. Since steam is used for rotation it is called steam turbine

.

Fig.2 Flow Diagram Of A Steam Turbine

Turbines also extract energy in fluid flow where the pressure is not high but where the fluid has sufficient fluid kinetic energy. The classic example is a wind turbine, which converts the wind’s kinetic energy to rotational energy. This type of kinetic energy conversion is common in green energy cycles for applications ranging from larger wind turbines to smaller hydrokinetic turbines currently being designed for and demonstrated in river and tidal applications. Turbines can be designed to work well in a variety of fluids, including gases and liquids, where they are used not only to drive generators, but also to drive compressors or pumps.

In other words, the primary purpose of the turbine is to reduce the temperature of the working fluid as opposed to providing power. Generally speaking, the higher the pressure ratio across a turbine, the greater the expansion and the greater the temperature drop. Even where turbines are used to cool fluids, the turbines still produce power and must be connected to a power absorbing device that is part of an overall system.

Also note that turbines in high inlet-pressure applications are sometimes called expanders. The terms “turbine” and “expander” can be used interchangeably for most applications, but expander is not used when referring to kinetic energy applications, as the fluid does not go through significant expansion.

2.2. ADVANTAGES:-

Ability to utilize high pressure and high temperature steam. High efficiency. High rotational speed. High capacity/weight ratio. Smooth, nearly vibration-free operation. No internal lubrication. Oil free exhausts steam.

2.3DISADVANTAGES:-

For slow speed application reduction gears are required. The steam turbine cannot be made reversible. The efficiency of small simple steam turbines is poor

STEAM TURBINES THE MAINSTAY OF BHEL:-

BHEL has the capability to design, manufacture and commission steam turbines of up to 1000 MW rating for steam parameters ranging from 30 bars to 300 bars pressure and initial & reheat temperatures up to 600ºC.

3. TYPES OF STEAM TURBINE

There are complicated methods to properly harness steam power that give rise to the two primary turbine designs: impulse and reaction turbines. These different designs engage the steam in a different method so as to turn the rotor

3.1 IMPULSE TURBINE

. The steam passes through the stationary nozzles and is directed at high velocity against rotor buckets causing the rotor to rotate at high speed. These turbines change the direction of flow of a high velocity fluid or gas jet. The resulting impulse spins the turbine and leaves the fluid flow with diminished kinetic energy. There is no pressure change of the fluid or gas in the turbine rotor blades as in the case of a steam or gas turbine, all the pressure drop takes place in the stationary blades.Before reaching the turbine, the fluid's pressure head is changed to velocity head by accelerating the fluid with a nozzle. Impulse turbines do not require a pressure casement around the rotor since the fluid jet is created by the nozzle prior to reachingthe blading on the rotor. Newton's second law describes the transfer of energy forimpulse turbines. The following events take place in the nozzles:

1. The steam pressure decreases.

2. The enthalpy of the steam decreases.

3. The steam velocity increases.

4. The volume of the steam increases.

5. There is a conversion of heat energy to kinetic energy as the heat energy from the decrease in

steam enthalpy is converted into kinetic energy by the increased steam velocity.

3.2 THE IMPULSE PRINCIPLESteam is expanded only in nozzle and pressure at outlet sides of the blade is equal to than at inlet side. Hence ,energy transformation takes place only in nozzle and moving blade only cause energy transfer.. The fact that the pressure does not drop across the moving blades is the distinguishing feature of the impulse turbine. The pressure at the inlet to the moving blades is the same as the pressure at the outlet from the moving blades.

3.3.1 REACTION TURBINE

A reaction turbine has rows of fixed blades alternating with rows of moving blades. The steam expands first in the stationary or fixed blades where it gains some velocity as it drops in pressure. It then enters the moving blades where its direction of flow is changed thus producing an impulse force on the moving blades. In addition, however, the steam upon passing through the moving blades again expands and further drops in pressure giving a reaction force to the blades. This sequence is repeated as the steam passes through additional rows of fixed and moving blades.

DIFFERENCES BETWEEN IMPULSE AND REACTION TURBINE

4. TURBINE PARTS

4.1 TURBINE BLADES

Cylindrical reaction blades for HP, IP and LP Turbines 3-DS blades, in initial stages of HP and IP Turbine, to reduce secondary losses. Twisted blade with integral shroud, in last stages of HP, IP and initial stages of LP

turbines, to reduce profile and Tip leakage losses

o Free standing LP moving blades Tip sections with supersonic design.

o Fir-tree root

o Flame hardening of the leading edge

o Banana type hollow guide blade

4.2 TURBINE CASING

Casings or cylinders are of the horizontal split type. This is not ideal, as the heavy flanges of the joints are slow to follow the temperature changes of the cylinder walls. However, for assembling and inspection purposes there is no other solution. The casing is heavy in order to withstand the high pressures and temperatures. It is general practice to let the thickness of walls and flanges decrease from inlet- to exhaust-end. The casing joints are made steam tight, without the use of gaskets, by matching the flange faces very exactly and very smoothly. The bolt holes in the flanges are drilled for smoothly fitting bolts, but dowel pins are often added to secure exact alignment of the flange joint. Double casings are used for very high steam pressures. The high pressure is applied to the inner casing, which is open at the exhaust end, letting the turbine exhaust to the outer casings.

4.3 TURBINE ROTORS

The design of a turbine rotor depends on the operating principle of the turbine. The impulse turbine with pressure drop across the stationary blades must have seals between stationary blades and the rotor. The smaller the sealing area, the smaller the leakage; therefore the stationary blades are mounted in diaphragms with labyrinth seals around thes haft. This construction requires a disc rotor. Basically there are two types of rotor:

DISC ROTORSAll larger disc rotors are now machined out of a solid forging of nickel steel; this should give the strongest rotor and a fully balanced rotor... The bore of the discs is made 0.1% smaller in diameter than the shaft. The discs are then heated until they easily are slid along the shaft and located in the correct position on the shaft and shaft key. A small clearance between the discs prevents thermal stress in the shaft

DRUM ROTORSThe first reaction turbines had solid forged drum rotors. They were strong, generally well balanced as they were machined over the total surface. With the increasing size of turbines the solid rotors got too heavy pieces. For good balance the drum must be machined both outside and inside and the drum must be open at one end. The second part of the rotor is the drum end cover with shaft.

Turbine governing system:

Mechanical governor:The purpose of a mechanical governor is to maintain the speed of the turbine at a desired value when the generator is disconnected from the power supply.

Main parts of mechanical governor:

Ø FlyweightsØ BracketØ Spring etc.

Mechanism:When the turbine shaft rotates, the governor flyweights respond to the centrifugal forces created by the rotations. As turbine speed increases, the centrifugal force increases, causing the flyweights tomove outward, overcoming the tension of the spring.

CONSTRUCTIONAL FEATURES OF A BLADE

The blade can be divided into 3 parts:

The profile, which converts the thermal energy of steam into kinetic energy, with a certain efficiency depending upon the profile shape.

The root, which fixes the blade to the turbine rotor, giving a proper anchor to the blade, and transmitting the kinetic energy of the blade to the rotor.

The damping element, which reduces the vibrations which necessarily occur in the blades due to the steam flowing through the blades. These damping elements may be integral with blades, or they may be separate elements mounted between the blades. Each of these elements will be separately dealt with in the following sections.

5.1 H.P. BLADE PROFILES

In order to understand the further explanation, a familiarity of the terminology used is required. The following terminology is used in the subsequent sections.

If circles are drawn tangential to the suction side and pressure side profiles of a blade, and their centers are joined by a curve, this curve is called the camber line. This camber line intersects the profile at two points A and B. The line joining these points is called chord, and the length of this line is called the chord length. A line which is tangential to the inlet and outlet edges is called the bitangent line. The angle which this line makes with the circumferential direction is called the setting angle. Pitch of a blade is the circumferential distance between any point on the profile and an identical point on the next blade.

5.2 CLASSIFICATION OF PROFILES

There are two basic types of profiles - Impulse and Reaction. In the impulse type of profiles, the entire heat drop of the stage occurs only in the stationary blades. In the reaction type of blades, the heat drop of the stage is distributed almost equally between the guide and moving blades.. The Steam turbines use the impulse profiles for the control stage (1st stage), and the reaction profiles for subsequent stages. There are four reasons for using impulse profile for the first stage:5.3 H.P. BLADE ROOTS

The root is a part of the blade that fixes the blade to the rotor or stator. Its design depends upon the centrifugal and steam bending forces of the blade.. The roots are T-root and Fork-root. The fork root has a higher load-carrying capacity than the T-root The typical roots used for the HP moving blades for various steam turbine applications are shown in the following figure:

T-ROOT

T-ROOT WITH SIDE GRIP

5.4 L.P. BLADE PROFILES

The LP blade profiles of moving blades are twisted and tapered. These blades are used when blade height-to-mean stage diameter ratio (h/Dm) exceeds 0.2.

5.5 LP BLADE ROOTSThe roots of LP blades are as follows:

1) 2 Blading :a. The roots of both the LP stages in –2 type of LP Blading are T-roots.

2) 3 Blading:a. The last stage LP blade of HK, SK and LK blades have a fork-root. SK blades

have4-fork roots for all sizes. HK blades have 4-fork roots up to 56 size, where modified profiles are used. Beyond this size, HK blades have 3 fork roots. LK blades have 3-forkroots for all sizes. The roots of the LP blades of preceding stages are of T-roots.

The damping in any blade can be of any of the following types:

a) Material damping: This type of damping is because of the inherent damping properties of the material which makes up the component.

b) Aerodynamic damping: This is due to the damping of the fluid which surrounds the component in operation.

c) Friction damping: This is due to the rubbing friction between the component under consideration with any other object.

BLOCK 3 LAY-OUT

8. CLASSIFICATION OF BLOCK 3

BAY-1 IS FURTHER DIVIDED INTO THREE PARTS

1. HMS

In this shop heavy machine work is done with the help of different NC &CNC machines such as center lathes, vertical and horizontal boring & milling machines. Asia’s largest vertical boring machine is installed here and CNC horizontal boring milling machines from Skoda of Czechoslovakia.

2. Assembly Section (of hydro turbines)In this section assembly of hydro turbines are done. Blades of turbine are1st assemble on

the rotor & after it this rotor is transported to balancing tunnel where the balancing is done. After balancing the rotor, rotor &casings both internal & external are transported to the customer. Total assembly of turbine is done in the company which purchased it by B.H.E.L.

3. OSBT (Over Speed Balancing Tunnel)In this section, rotors of all type of turbines like LP(low pressure), HP(high pressure) &

IP(Intermediate pressure) rotors of Steam turbine ,rotors of Gas & Hydro turbine are balanced .In a large tunnel, Vacuum of 2 torr is created with the help of pumps & after that rotor is placed on pedestal and rotted with speed of 2500-4500 rpm. After it in a computer control room the axis of rotation of rotor is seen with help of computer & then balance the rotor by inserting the small balancing weight in the grooves cut on rotor.

Fig 4: Over speed & Vacuum Balancing TunnelFor balancing and over speed testing of rotors up to 320 tons in weight, 1800 mm in length and 6900 mm diameter under vacuum conditions of 1 Torr.

BAY –2 IS DIVIDED IN TO 2 PARTS:

1. HMSIn this shop several components of steam turbine like LP, HP & IP rotors, Internal & external casing are manufactured with the help of different operations carried out through different NC & CNC machines like grinding, drilling, vertical & horizontal milling and boring machines, center lathes, planer, Kopp milling machine.

2. Assembly SectionIn this section assembly of steam turbines up to 1000 MWIs assembled. 1st moving blades are

inserted in the grooves cut on circumferences of rotor, then rotor is balanced in balancing tunnel in bay-1.After is done in which guide blades are assembled inside the internal casing & then rotor is fitted inside this casing. After it this internal casing with rotor is inserted into the external.

BAY 3 IS DIVIDED INTO 3 PARTS:

1. Bearing SectionIn this section Journal bearings are manufactured which are used in turbines to overcome

the vibration & rolling friction by providing the proper lubrication.

2. Turning SectionIn this section small lathe machines, milling & boring machines, grinding machines &

drilling machines are installed. In this section small jobs are manufactured like rings, studs, disks etc.

3. Governing SectionIn this section governors are manufactured. These governors are used in turbines for

controlling the speed of rotor within the certain limits. 1st all components of governor are made by different operations then these all parts are treated in heat treatment shop for providing the hardness. Then these all components are assembled into casing. There are more than 1000 components of Governor.

BAY-4 IS DIVIDED INTO 3 PARTS:

1. TBM (Turbine Blade Manufacturing) ShopIn this shop solid blade of both steam & gas turbine are manufactured. Several

CNC & NC machines are installed here such as Copying machine, Grinding machine, Rhomboid milling machine, Duplex milling machine, T- root machine center, Horizontal tooling center, Vertical & horizontal boring machine etc.

Fig 5. Steam Turbine Casing & Rotors in Assembly Area

2. Turning SectionSame as the turning section in Bay-3, there are several small Machine like lathes

machines, milling, boring, grinding machines etc.

Fig 6. CNC Rotor Turning Lathe

3. Heat Treatment ShopIn this shop there are several tests performed for checking the Hardness of different

components. Tests performed are Sereliting, Nitriding, DP Test.

9. BLADE SHOP

Blade shop is an important shop of Block 3. Blades of all the stages of turbine are made in this shop only. They have a variety of centre lathe and CNC machines to perform the complete operation of blades. The designs of the blades are sent to the shop and the Respective job is distributed to the operators. Operators perform their job in a fixed interval of time.

9.1 TYPES OF BLADES

Basically the design of blades is classified according to the stages of turbine. The size of LP TURBINE BLADES is generally greater than that of HP TURBINE BLADES. At the first T1, T2, T3 & T4 kinds of blades were used, these were 2nd generation blades. Then it was replaced by TX, BDS (for HP TURBINE) & F shaped blades. The most modern blades are F & Z shaped blades.

3 Dimesional Cylindrical Profile Twisted Profile3DS Blade TX Blade F BladeHP/IP Initial Stages HP/IP Intermediate stages HP/IP Rear Stages

& LP Initial

Fig. 7 Types Of Blades

9.2 OPERATIONS PERFORMED ON BLADESSome of the important operations performed on blade manufacturing are:-

Milling Blank Cutting Grinding of both the surfaces Cutting Root milling

9.3 MACHINING OF BLADESMachining of blades is done with the help of Lathe & CNC machines. Some of the machines are:-

Centre lathe machine Vertical Boring machine Vertical Milling machine CNC lathe machine

Fig 8. Schmetic Diagram of a CNC Machine

9.4 NEW BLADE SHOP

A new blade shop is being in operation, mostly 500mw turbine blades are manufactured in this shop. This is a highly hi tech shop where complete manufacturing of blades is done using single advanced CNC machines. Complete blades are finished using modernized CNC machines. Some of the machines are:-

Pama CNC ram boring machine. Wotum horizontal machine with 6 axis CNC control. CNC shaping machine.

Fig 9. CNC Shaping Machine

10. CONCLUSION

Gone through rigorous 6 Weeks training under the guidance of capable engineers and workers of BHEL Haridwar in Block-3 “TURBINE MANUFACTURING” headed by Senior Engineer of department Mr. SUSIL KUMAR RAWAT situated in Ranipur, Haridwar,(Uttarakhand).

The training was specified under the Turbine Manufacturing Department. Working under the department I came to know about the basic grinding, scaling and machining processes which was shown on heavy to medium machines. Duty lathes were planted in the same line where the specified work was undertaken.

The training brought to my knowledge the various machining and fabrication processes went not only in the manufacturing of blades but other parts of the turbine.