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INTERNSHIP REPORT ON NCTPS(NORTH CHENNAI THERMAL POWER STATION)...

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AN INTERNSHIP REPORT ON “RASTRYA ISPHAT NIGAM LIMTED, ASHOK LEYLAND AND NORTH CHENNAI THERMAL POWER STATION ”

A dissertation submitted in partial fulfillment of the Requirements for the award of

BACHELOR OF TECHNOLOGY IN MECHANICAL ENGINEERING BY KARAJADA VENKATA SATYA RAGHUVAMSI

(N130467)

RAJIV GANDHI UNIVERSITY OF KNOWLEDGE TECHNOLOGIES IIIT NUZVID 521202 KRISHNA Dist. A.P

RAJIV GANDHI UNIVERSITY OF KNOWLEDGE TECHNOLOGIES IIIT NUZVID 521202 KRISHNA Dist. A.P

CERTIFICATE

This is to certify that the internship report entitled “INPLANT TRAINING REPORT ON RASTRIYA ISPHAT NIGAM LIMTED, ASHOK LEYLAND AND NORTH CHENNAI THERMAL POWER PLANT ” being submitted by

KARAJADA VENKATA SATYA RAGHUVAMSI

(N130467)

In partial fulfillment for the award of the degree of BACHELOR OF TECHNOLOGY in MECHANICAL ENGINEERNIG

DEPT

from

RAJIV

GANDHI

UNIVERSITY

OF

KNOWLEDGE TECHNOLOGIES, IIIT NUZVID 521202 KRISHNA Dist. A.P is a bonafide work carried out by them under my guidance & supervision.

Project Guide MR. M. LAKSHMANARAO

Head of the Department MR. P. PRADEEP

TABLE OF CONTENTS 1.INTERNSHIP REPORT ON VIZAG STEEL PLANT 1.11.1 PROFILE OF VSP 1.2 RAW MATERIAL HANDLING PLANT 1.3 COKE OVENS AND COAL CHEMICAL DIVISION 1.4 SINTER PLANT 1.5 BLAST FURNACE 1.6 STEEL MELTING SHOP (SMS) 1.7 CONTINUOUS CASTING DEPARTMENT 1.8 ROLLING MILLS 1.9 WIRE ROD MILL 1.10 MEDIUM MERCHANT AND STRUCTURAL MILL 1.11 LIGHT AND MEDIUM MERCHANT MILL (LMMM) 1.11.1 BILLET MILL 1.11.2 WALKING BEAM FURNACE 1.11.3 DESCRIPTION OF A WALKING BEAM FURANCE 1.11.4 FUELS IN FURNACE 1.11.5 BREAK DOWN MILL AREA 1.11.6 BILLET MILL COOLING BED AREA 1.12 BAR MILL 1.12.1 DESCRIPTION OF PROCESS 1.12.2 DIVERT SWITCH 1.12.3 ROUGHING MILL 1.12.4 FINISHING AREA 1.13 TEMPCORE PROCESS 2. INTERNSHIP REPORT ON ASHOK LEYLAND 2.1 CHASIS ASSEMBlY 2.2 ENGINE ASSEMBLY 2.3 ENGINE TESTING AND ANLYSIS

2.4 CAM SHAFT MACHINING

3.INPLANT TRAINING REORT ON NORTH CHENNAI THERMAL POWER STATION 3.1 INTRODUCTION TO THERMAL POWER PLAN 3.2 DEMINERLISATION OF WATER 3.3 AIR CONDITIONING 3.4 BOILER MAINTAINCE 3.5 TURBINE MAINTAINCE 3.6 MILL PLANT MANGEMNET 3.7 CALCUALTION OF EFFICENCY OF PLANT

INPLANT TRAINING REPORT ON VISKHAPATNAM STEEL PLANT

1.1 PROFILE OF VSP Visakhapatnam Steel Plant, the first coast based Steel Plant of India is located, 16km southwest of City of Destiny i.e., Visakhapatnam. The plant is located amidst nature’s bounty, in the city fast emerging as the face of the future and also with the pictures of Ghats on one side and the mighty Bay of Bengal on the other bestowed with modern technologies, Visakhapatnam Steel Plant has an installed capacity of • 3 Million Tons per annum of liquid steel and • 2.656 Million Tons of saleable steel. VSP has become the first integrated steel plant in the country to be certified to all the three international standards for quality (ISO-9001), for environment management (ISO-14001) and for occupational health & safety (OHSAS-18001).

Visakhapatnam Steel Plant products meet exalting International Quality Standards such as JIS, DIN, BIS, BS etc. Visakhapatnam Steel Plant by successfully installing and operating efficiently Rs.460 crores worth of Pollution Control and Environment Control equipments and converting the barren landscape by planting more than 3 million plants has made the Steel Plant, Steel Township and surrounding areas into a heaven of lush greenery. This has made Steel Township a greener, cleaner and cooler place, which can boast of 3 to 4 degrees centigrade lesser temperature even in peak summer compared to Visakhapatnam city. Visakhapatnam Steel Plant exports quality pig iron and steel products too Sri Lanka, Myanmar, Middle East, USA and Southeast Asia (pig iron). RINL-VSP was awarded “Star Trading House” status during 1997-2000and recently it has bagged the prestigious “NAVARATNA” award.

MAJOR DEPARTMENTS IN VISAKHAPATNAM STEEL PLANT 1.2 RAW MATERIAL HANDLING PLANT: VSP annually requires quality raw materials viz. iron ore, fluxes (Limestone, dolomite) coking and non-coking coals, etc. to the tune of 12-13 million tons for producing 3 million tons of liquid steel. To handle such a large volume of incoming raw materials received from different sources and to ensure timely supply of consistent quality of feed materials to different VSP consumers, Raw material Handling Plant serves a vital function. This unit is provided with elaborate unloading, blending, stacking and reclaiming facilities viz. Wagon Tipplers, Ground and Tank Hoppers, Stock yards, Crushing Plants, Vibrating Screens, Single/ twin boom stackers, Wheels on boom and Blender Reclaimers. In VSP Peripheral unloading has been adopted for the first time in the country.

Fig. Raw material handling plant The steel plant is getting its supply of iron ore lumps and fines from the Bailadilla deposits in Madhya Pradesh (MP) blast furnace grade limestone from Jaggayyapeta in Andhra Pradesh, SMS grade lime stone from Badnapur in MP, blast furnace grade limestone from the Kotni-sonor deposits in MP. 20% of cocking coal requirements will be met by imports through the

Vishakhapatnam harbor while the balance will come from the Bengal-Bihar. Coal for power generation will come from Talcher in Orissa.

MAJOR SOURCES OF RAW MATERIALS FOR VSP ` RAW MATERIAL Iron ore Lumps & Fines BF Lime Stone SMS Lime Stone BF Dolomite SMS Dolomite Manganese Ore Boiler Coal Coking Coal Medium Coking Coal

SOURCE Bailadilla, MP Jaggayyapeta, AP UAE Madharam, AP Madharam, AP Chipurupalli, AP Talcher, Orissa Australia Gidi/Sawang/Rajarappa

1.3 COKE OVENS AND COAL CHEMICAL DIVISION The department of VSP has four coke oven batteries for producing 3.26 million tons of dry coke. Each battery has 67 ovens of 7 meters height. Coke is manufactured by heating of crushed coking coal (below 3mm) in absence of air at temperature of 1000’c and above 16 to 18 hours. At VSP there are three coke oven batteries, 7 meter tall and having 67 ovens each. Each oven is having a volume of 41.6 cu meters and can hold up to 31.6 tons of dry coal charge. The carbonization takes place at 10001050’C in absence of air for 16 -18 hours red hot coke is pushed out of the oven and sent to coke. Dry cooling plants where nitrogen gas is used as the cooling medium. The heat recovery from nitrogen is done by generating steam and expanding into back pressure turbines to produce powers. Coking coal after selective crushing and proper blending is subjected to destructive distillation (heating in the absence of air) in the Coke Ovens. Another feature is the dry cooling of coke carried out by the inert gas nitrogen thus; reducing pollution considerably besides a bio-chemical plant separately undertakes the treatment of effluents. By-products like benzene, toluene, xylene, napthalene, coal tar, creosote oil, pitch; ammonium sulphate and benzol products are also recovered from the coke ovens gas. VSP produces, among other by-products, pushkala a prime fertilizer based on ammonium sulphate. .

Fig. Coke oven batteries

1.4 SINTER PLANT Sinter is a hard and porous ferrous material obtained by agglomeration of iron ore fines, coke breeze, limestone fines, metallurgical waste like flue dust, mill scale, LD slag etc. Sinter is a better-feed material to blast furnace in comparison to iron ore lumps and its usage in blast furnaces help in increasing productivity, decreasing the coke rate and improving the quality of hot metal produced. Sintering in two sinter machines of 312 sq.m by heating the prepared feed on a continuous metallic belt made of pallets at 1200-1300 °C. Hot sinter discharged from .sintering machine is crushed to 5mm-50mm size and cooled before dispatching to blast furnace. Sinter is 80% of the input charged in the Blast Furnace.

Fig. Sinter plant

1.5 BLAST FURNACE Sinter along with iron ore and coke is charged to Blast Furnace to produce molten iron in presence of hot air blast. There are two Blast Furnaces of 3200 meter cube useful volumes, each capable of producing 1.3 MT of hot metal per annum. Charging to furnace is through Paul worth, Bell less top charging system. Each furnace is designed for 2.5 at a top pressure and is provided with a set of four hot blast stoves designed to supply air blast up to 1300C. Three turbo-blowers, one for each furnace and one stand by common to both furnaces are provided in Power Plant and Blower House for supplying Blast air in to the furnace. Each furnace is provided with 12MW top pressure recoveries Turbo Generator for generating power. BF gas produced from furnaces is cleaned in Gas cleaning plant comprising of dust catcher, scrubbers and high pressure ventures and is distributed throughout the plant as fuel.

Fig. Blast Furnace

1.6 STEEL MELTING SHOP (SMS) Molten from along with scrap and lime stone are charged to three LD converters, each of 150 tones capacity. The tap to tap cycle is 50 minutes for each converter. The LD gas generated during steel making is recovered through gas cleaning plant and gas recovery plant and is used as fuel in furnace. Six four-strand bloom caster with radial type continuous machine cast bloom frame liquid steel continuous casting of such large scale is for the first time in India. VSP employees three top blown oxygen converts called LD-converters each having 133cum volume capable of producing three million tones of liquid steel annually 99.5 % of pure oxygen at 15-16 KSCG pressure is blow in the converter through an oxygen lance having convergent-divergent copper nozzles at the blowing end. Oxygen oxidizes the impurities present in the hot metal that are fixed at slag with basic fluxes such as lime. During the process heat is generated by exothermic reactions of oxidation of metalloids like Si, Mn, P & C and temperature raises 1700°C enabling refining and slag formation. This process can make different grades of steel of superior quality by controlling the oxygen blow or addition of various Ferro Alloys or special additives, such as Fe-Si, Fe-Mn, Si-Mn, Coke breeze, Al in required quantities while liquid steel is being trapped from the converter into a steel ladle. Converter gas produces as a bi-product is used as secondary fuel.

Fig. Steel Melting Shop (SMS)

Fig. LD Converter

1.7 CONTINUOUS CASTING DEPARTMENT Continuous casting may be defined as teaming of liquid steel in a mould with a false bottom through which partially solidified ingot/bar (Similar to the shape & cross section of the mould) is continuously withdrawn at the same rate which liquid steel is teamed in the mould. At VSP, we have six-4 strand continuous casting machines capable of Producing 2.82 MT/Year Blooms of size 250X250 mm and 250X320 mm. Entire quantity of molten steel produced (100%) is continuously cast in radial bloom casters which help in energy conservation as well as production of superior quality products.

Fig. Continuous Casting Machine

Fig. LD Converters

1.8 ROLLING MILLS Blooms produced in SMS-CCD do not find many applications, as such are required to be shaped into products such as billets, rounds, squares, angles (equal and unequal), channels, IPE beams, HE beams, wire rods and reinforcement bars by rolling them in 3 high capacity, high speed fully automatic rolling mills namely Light and Medium Merchant Mills (LMMM), Wire rod mill (WRM) and Medium Merchant and Structural Mill (MMSM). 1.9 WIRE ROD MILL The Wire Rod Mill of VSP is high speed 4 strand No-Twist continuous mill designed to produce 0.85 MT/yr of wire rod coils. The mill is designed to produce plain wire rods from 5.5 mm to 12.7 mm diameter and Rebar in 8mm, 10mm and 12 mm diameter in coil form. However sizes up to 14 mm diameter are being rolled presently. The mill is constructed at an elevated level of 5350 mm. Rolled billets of 125 mm x 125 mm square cross section, length ranging from 9.8 m to 10.4 m and weighing approx 1250 kgs are used as input material. The mill is designed to roll steel stock of 0.9% max Carbon content.

Fig. Product (wires) of Wire Rod Mill

STRCTURE OF MILL • • • •

7 Strand Roughing Mill (4 Strand rolling) 6 Strand Intermediate Mill (4 Strand rolling) 4x2 Strand Pre-finishing Mill (Single Strand rolling) 4x10 Strand Finishing Mill (Single Strand rolling) Salient Features

• Evaporative cooling system in Rolling Mill furnaces. • Computerization in Rolling Mill • Controlled cooling of Wire Rods, by 'Stelmore' process giving high strength and good ductility. Capacity: A Mill of 0.85 MT per annum production capacity.

1.10 MEDIUM MERCHANT AND STRUCTURAL MILL This mill is a high capacity continuous mill consisting of 20 stands arranged in 3 trains. 1. Roughening train having 8 strands. 2. Intermediate train having 6 strands. 3. Finishing train having 6 strands. The feed material to the mill is 250X250 mm size blooms, which are heated to rolling temperatures of 1200 0C in two walking beam furnaces each of 130 TPH capacities. The mill is capable of producing 8,50,000 tons of rounds, squares, flats, angles (equal and unequal) T bars, Channels, IPE beams/ HE beams ( UNIVERSAL BEAMS) having high strength and close tolerances.

Fig . MMSM PRODUCTS The important feature of this mill is that Universal beams (both parallel and wide flange) have been rolled first time in India using universal strands. Parallel beams have advantage over conventional beams as per the same weight the section is stronger and stiffer due to greater moment of inertia and higher radius of gyration.

1.11 LIGHT AND MEDIUM MERCHANT MILL (LMMM)

The light and medium merchant mill (LMMM) Visakhapatnam steel plant is envisaged to produce • 7, 10,000 Tons /yr of LMMM products. • 2, 46,000 Tons /yr of Billets for sale. • 8, 85,000 Tons /yr of Billets for WRM at 3.0 MT stage.

in

Keeping in view the latest developments the light and medium merchant will is designed with the operation floor on a second store elevation, namely +5.0 meters. This arrangement has many advantages. It provides better drainages for both lubricants and water and mill scale. The oil cellars can be placed at slightly below the ground level without deep excavations but ensuring adequate drainage. The oil and water pipes and cable trenches are readily accessible. The material is lifted up the elevated floor on to the working bay means of elevators. Some of the Salient features of the mill are: A. High capacity and high speed. B. Automatic minimum tension control in stands C. Double side cooling beds of walking beam type. D. High capacity and high productive sawing lines. E. Automatic bundling machines. F. Computerization at the sequential process control and material tracking G. Adoption of closed circuit TV at furnaces. H. evaporative cooling system and waste heat recovery.

These features help to optimize the production and assure quality products from the mill. 1.11.1 BILLET MILL Blooms for LMMM are placed on charging grids (3 in number) of 150 tons per hour capacity each by 16 tons claw cranes (2 in number). The blooms are then delivered to the furnace approach roller table (+5.8mts) by an inclined elevator from bloom storage roller table (+0.8mts). 1.11.2 WALKING BEAM FURNACE There are two walking beam furnace, which have their discharge sides situated on the Mill bay , which stretches about 960 meters long house the combined Billet and Bar mill with its inline roller heating hearth furnace ,cooling beds and cold shears . The finished facilities viz., bundling and piling installations are laid out across the cold shear delivery roller table. The feed material for the mill is continuous cast bloom of 250mm x 320mm size having a normal length 6.3 meter. Cold blooms are charged on the charging grids by magnet crane according to the rolling crane list .Normally furnace 1 is intended to feed hot blooms for production of billets and deposition on to the billet cooling bed while furnace 2 is intended to feed hot blooms for onward transmission to the bar mill.

This implies that cold blooms are to be charged into charging grids in a definite pattern to suit the particular rolling mode adopted and particular grid can be operated for discharging of blooms on to the roller table upon ON light flashing and the light will go OFF when prescribed number of blooms have been discharged. The respective grid will go OFF when the preselected number of blooms have been discharged on to the roller table .When the blooms have passes the roller table section in front of another grid, the light of the grid will be ON permitting the grid to discharge the blooms .Blooms are discharged from the roller table and conveyed to the elevator. Detective blooms, if any, on its travel to the elevator will be detected manually by the operator and positioned in front of defective bloom grids and will be pushed out of the roller table. The roller table transports the blooms normally under sequence control of their respective destined positions elevators 1 or 2 .The blooms are pushed off the roller table by the lever type off on to a ramp where they are picked up by the carrier links of elevators and pulled up. They carry off device down streams and pick up the bloom and places on the furnace approach roller table. The furnace approach roller table working on sequential control, positions the blooms while on motion on various sections of this

roller by means of light barrier. Since the walking beam systems are uniformly loaded different bloom lengths will be classified into two categories and positioned in front of furnaces automatically. The blooms on its passage are stopped and its actual weight is recorded. The material tracking computer system takes over the actual weight, checks with reference weights and then sets the blooms free for further transport. As soon as the bloom is positioned correctly and the walking beam furnace is ready to receive the blooms, the blooms are pushed into the furnace by furnace pusher. Two waking beam furnace each having a through output capacity of 200 t/h are provided for starting stock reheating. In each of these furnaces, the blooms disposed at predetermined spaces are passed through the furnace unit in steps. Lift able and lower able walking beams adapted to move in horizontal steps carry the blooms for advance transport and after each step redeposit them on the fixed beams. The locally defined contact between walking beams and blooms is just time limited and then changes over to the other contact points with the fixed beams .The formation of cold spots is avoided this way and in addition to top heating, underside heating is also possible in the equalization zone .Due to this fact and also due to the relative spacing of blooms on

their way through the furnace, the overall furnace length is reduced compared to a pusher type furnace unit

BLOOM PUSHER PUSHING BLOOMS INTO WBF

1.11.3 DESCRIPTION OF A WALKING BEAM FURNACE The furnace is charged in 2 rows by means of approach roller table. Bloom pushers take care of pushing the blooms in pairs into the starting positions on the fixed carrier tube system and simultaneously centering them rectangular to furnace by the so called walking beam system i.e., the bloom is lifted off the starting position from the fixed hearth, moved one step towards the discharge side and then are disposed on the fixed hearth. The movement characteristic is rectangular. This way the bloom is

transported through the furnace one step by step and simultaneously heated up to rolling temperature by the time it is discharged from the discharging end. the billets heated up to the rolling temperature by means of discharging device which take over the billet from defined Passover position on the furnace run out roller table .Each furnace has a clear length of 29400mm and a clear w...