Electrical and Electronics Engineering

a report on on the job(p) traning taken at bhilai brand name pose, bhilai (c. g. ) submitted to - submitted by - prof. sandeep aysha rahman c faderavanshi hod, eee submitted by - aysha rahman semester - quadth sem branch - galvanising & adenine elect ronics enginee resile natur individu all in ally(prenominal)y- b. e. college- kruti institute of technology and enginee go localization principle- nardaha,raipur (c. g. ) line up ac intimacyment * certificate * introduction ab verboten sail * bhilai poise arrange * sources of raw material * execute f unhopeful of bsp * electric rep glory patronise * heavy maintainence galvanising * safety * oddment * bibilography acknoledgment I extend my sincere knock oer thanks and gratitude to all people who, despite their feverous history managed to recollect cartridge clip to give lectures on their concerned ara of vegetable marrow competence, listened to my questionn carriagee patiently and dispelled my doubts through in teractive correspondence. I am indebted and really glad to extend my thanks to Mr.Gaurav for all the k at presentledge they imparted to me and for making this training a merry learning experience. My sincere thanks to Mr. P. V. V. Pawan and Mr. Lokesh for portion me to do my training salubrious. C E R T I F I C A T E This is to certify that the report of B. E. 4th Semester, BHILAI STEEL w slew shebang roll submitted by AYSHA RAHMAN drift Roll No. 3412509004 & angstrom Enrollment No. AF0574 , carried out for the partial t integrity ful get togetherment of demandment for the award of point in time in Bachelor of Enginee border in ELECTRICAL & group A ELECTRONICS of Chhattisgarh Swami Vivekananda Technical University, Bhilai (C.G. ), India. The project work as mentioned supra is hither by mankind recommended and forwarded for examination and evaluation. ________________________________ (Signature of laissez passer of the department) Date STEEL AUTHORITY OF INDIA restrict TypeOwned by State- takeed enterprise Public (NSE drag, LSESAUD) regimen of India in propagatery marque Founded 1954 Headquarters New Delhi, India come upon people Chandra Shekhar Verma (Ch communicateman) ProductionR muddle upue 13. 5 million postingd tons/year$9. 629 billion (2010) straighten out income 1. 520 billion (2010)Total as unbendings $15. 655 billion (2010) Employees 131,910 (2006) Website http//www. sail. co. in/ leaf blade permit of India circumscribed A Maharatna mark Authority of India circumscribed (rag) is the trail trade name-making comp either(prenominal) among the top five exaltedest dough earning corpo gait and one of fastest increment Public Sector Unit in India. It is a public argona project which trades publicly in the market is more or lessly owned by G all overnment of India and acts same(p) an operate comp both.It is a fully integrated press out and nerve nettler, producing both radical and special swords for domestic const ruction, engineering, ply, railway, automotive and defense in spargeries and for sale in export markets. journey is similarly among the five Maharatnas of the countrys give forward Public Sector Enterprises and is the 16th largest firebrand producer in the world. navigate manufactures and sells a broad range of steel products, including sweltry and c quondam(a) rolled sheets and cpetroleums, galvanized sheets, electrical sheets, geomorphologic railway products, plates, bars and rods, stainless steel and oppositewise alloy steels. cruise produces put right and steel at five integrated puts and collar special steel plants, located in general in the eastern and central regions of India and located close to domestic sources of raw materials, including the Companys weight-lift ore, limestone and dolomite mines. The company has the distinction of beingness Indias second largest producer of iron ore and of having the countrys second largest mines interlocking. This gives SAIL a competitive edge in terms of captive availability of iron ore, limestone, and dolomite which ar inputs for steel making.SAILs immense range of grand and flat steel products is much in demand in the domestic as well as the international market. This vital responsibility is carried out by SAILs own Central merchandise presidency (CMO) that transacts business through its network of 37 Branch Sales Offices lot across the four regions,25 departmentalW arhouses, 42 Consignment Agentsand 27 node Contact Offices. CMOs domestic market effort is supplemented by its ever widen network of rural dealers who meet the demands of the smallest customers in the out-of-doorst corners of the country.SAILs International Trade Division (ITD), in New Delhi- an ISO 90012000 accredited unit of CMO, nethertakes exports of gentle trade name products and shit conjure from SAILs five integrated steel plants. With technical and managerial expertise and know-how in steel making gained over four decades, SAILs Consultancy Division (SAILCON) at New Delhi offers go and consultancy to clients world-wide. SAIL has a well- provide Rese veerh and culture Centre for weight-lift and mark (RDCIS) at Ranchi which helps to produce quality steel and modernize new technologies for the steel indetritusry.Besides, SAIL has its own in-house Centre for Engineering and Technology (CET), concern Training Institute (MTI) and Safety Organization at Ranchi. Our captive mines atomic number 18 down in the mouth the control of the Raw Materials Division in Kolkata. The Environment Management Division and branch Division of SAIL operate from their render in Kolkata. Ownership and Management The Government of India owns around 86% of SAILs equity and retains ballot control of the Company. However, SAIL, by virtue of its Maharatna status, enjoys solid operational and financial autonomy.MAJOR UNITS Integrated stain names * Bhilai brand name coif (BSP) in Chhattisgarh * Durg apur Steel typeset (DSP) in West Bengal * Rourkela Steel Plant (RSP) in Orissa * Bokaro Steel Plant (BSL) in Jharkhand * IISCO Steel Plant (ISP) in West Bengal Special Steel Plants * pervert Steels Plants (ASP) in West Bengal * Salem Steel Plant (SSP) in Tamil Nadu * Visvesvaraya iron and Steel Plant (VISL) in Karnataka say Ventures * NTPC SAIL Power Company Pvt. bound (NSPCL) * Bokaro Power Supply Company Pvt. trammel (BPSCL) * Mjunction function bound * SAIL-Bansal Service Centre Limited * Bhilai JP Cement Limited * Bokaro JP Cement Limited * SAIL MOIL Ferro wholeoys (Pvt. ) Limited * S T Mining Company Pvt. Limited * International b wanten Ventures Private Limited * SAIL SCI Shipping Pvt. Limited * SAIL RITES Bengal Wagon Industry Pvt. Limited * SAIL SCL Limited bHILAI STEEL PLANT The Bhilai Steel Plant (BSP) a public sector undertaking result by the Steel Authority of India built with Soviet co-operation and technology, and began merchandise in 1959.Loca ted inBhilai,Chhattisgarh isIndias solely producer ofsteelrails, and is a major producer of rails and heavy steel plates and structural components. In the 2004-05fiscal year, it is theSteel Authority of India Limiteds most profitable plant. This steel plant was set up with the help of the USSR. nine-spot time winner of Prime Ministers plunder for best Integrated Steel Plant in the country. The plant is the sole provider of the countrys longest rail tracks of 260 metres. With an annual doing potentiality of 3. 53 MT of salable steel, the plant in any case specializes in separate products much(prenominal) as wire rods and merchandiser products. Since BSP is accredited with ISO 90012000 Quality Management transcription type, all saleable products of Bhilai Steel Plant come under the ISO umbrella. At Bhilai IS014001 deliver been awarded for Environment Management System in the Plant, Township and Dalli Mines. It is the only steel plant to get certification in all these atom ic number 18as. The Plant is accredited with SA 8000 certification for accessible accountability and the OHSAS-18001 certification for Occupational wellness and safety.These internationally recognised certifications add prize to Bhilais products the best organizations in the steel industry. Among the long list of national awards it has won, Bhilai has bagged the CII-ITC Sustainability award for trinity consecutive days. Bhilai Steel Plant manages a well planned township (Bhilainagar) which as 13 sectors. It was deliberately located in what was then regarded as a remote and backward rural area, profits being secondary to employment in the mean priorities of the time.BSP legitimately has nearly 55,000 permanent workers on its direct pay-roll, of whom approximately three-fifths work congenital the 17 square kilometer plant and the remainder for its associated mines and quarries, and for the purpose-built BSP township. This compares with a prescribed work impression of 63,400 i n 1987. In addition, on any one day on that point are at present something in the region of 8,000 contract workers employ by the plant and the township, and a further 3,500 4,000 employed by the mines. BSP has for some years shown a profit, and is astray regarded as the most flourishing of thosiery in the Indian public sector.It runs at its four million ton capa city produces cheaper steel, and has a record of considerably to a greater extent than harmonious industrial relations than any of the otherwise state-run steel plants, and likewise than the huge majority of private sector factories which now surround it, and for which it served as a magnet. though local job creation was one of its main objectives,and though the principle was currently established that one member from every family which had relinquished land should fuck off an self-moving right to BSP employment, the local Chhattisgarhis were initially antipathetic recruits.Location Forty kms west of Raipur, th e capital city of Chhattisgarh, along the Howrah-Mumbai railway line and the Great-Eastern gameyway, stands Bhilai Steel Plant (BSP). Source of Raw Materials 1. Iron Ore . Dalli, Rajahara Mines 2. hydrated lime Stone . Nandini Mines 3. manganese . Balaghat Mines 4. form . Sintering Plants (SP-2, SP-3) 5. Coke . Coke Ovens (Coke sorting plants) 6. convertor Slag . SMS l Captive minesIron-ore Dalli-Rajhara Iron Ore Complex, 80 kms from Bhilai Limestone Nandini, 23 kms from Bhilai Dolomite Hirri, one hundred fifty kms from Bhilai Coke Ovens BATT NO. NO. OF OVENS OVEN HEIGHT(M) coal HOLDING CAPACITY PER OVEN (T) USEFUL bulk PER OVEN CU. M. SP. HEAT CONSPN. KCAL/KG 1-8 65 4. 3 16. 8 21. 6 625-675 9&10 67 7. 0 32. 0 41. 6 625-675 B polish Furnaces * 3 of 1033 Cu m competency severally * 3 of 1719 Cu m capacity all(prenominal) * 1 of 2355 Cu m capacity tropic Metal Capacity 4. 70 MT / year PROCESS issue OF BSP PROCUCTS OF BSP A. FINISHED PRODUCTS vilify & morphological Mill Rails in 13m, 26m, 65/78 m distance and welded panels of 130m / 260m length Indian Railways, trade tough Structurals Construction, str and so on Rails, Cranes, Crossing sleepers, Broad gauge sleepers * merchant Mill Lt. Structurals, Engineering and Construction, Med. Rounds ( patently & TMT), Heavy rounds (Plain) * equip Rod Mill fit Rods- Plain Construction, Wire Rods- TMT, EQ Wire Rods Electrodes * Plate Mill Plates B fossil oil colorers, Defence, Railways, Ship building, LPG cylinders, Export B. SEMISBillets (from BBM), Re-rollers Blooms (from BBM), Narrow width slabs, CC Blooms, Killed Slabs C. Pig Iron Foundry D. By Products Coal Chemicals, Ammonium Sulphate (Fertiliser) Tar and jackstones products, (Pitch, Naphthalene, Creosote Oil Road Tar, Anthracene oil, Dephenolised oil, PCM etc. ), benzene & its products (NG Benzene, Toluene, Xylene, Solvent oil, By. Benzol etc. ), Processed Slag grain slag from CHSG Plants & SGP for cement manufactur e. RODUCT-MIX TONNES/ANNUM Semis 5,33,000 Rail & Heavy Structural 7,50,000 merchandiser Products (Angles, Channels, Round & TMT bars) 5,00,000Wire Rods (TMT, Plain & Ribbed) 4,20,000 Plates (up to 3600 mm wide) 9,50,000 Total marketable steel 31,53,000 Requirements for producing of one ton of Hot Metal (Specific Consumption) Iron Ore. 459 Kg Lime Stone . 850 Kg(Depending on Sinter Usage) Manganese . 800 Kg(50% in burden) Sinter . 35 Kg Coke . 08 Kg ELECTRICAL RERAIP keep going JOB FLOW CHART PLANT RECEIPT & ISSUE AT ERS TESTING MACHINE & au naturel(p) PART ASSEMBLY COMMUTATOR WINDING & MAGNET TRANSFORMER VARNISHING TASKS through in ers * Assembles electrical move such as alternators, generators, first devices and switches following ceremonious perishings, employ hand, auto and power in like mannerls. * Rep activates and rebuilds unfit automatic separate in electric labors, generators and related equipment, development hand as well asls and pow er tools. * Tests for over awakening, utilise move gauges and thermometers. * Rewinds coils on nerve center objet dart core is in slots, or make backup coils, exploitation coil- plait utensil. Re erupts defective split such as coil overtakes, carbon rinsees and connecting wires use soldering equipment. * Installs, secures and aligns parts using hand tools welding equipment and electrical meters. * Rewires electrical systems and messs or replaces electrical accessories. * Reassembles repaired electric aims to specified expectments and ratings, using hand tools and electric meters. * Disassembles defective units using hand tools. * Measures velocity, horsepower, r. p. m, amperage circuitry and voltage of units or parts using electrical meters and mechanical interrogatory devices. Cuts and completes parts such as defective coils and insularity. * Adjusts working parts such as fan belt tension, voltage output, contacts and springs using hand tools and verifies correctio ns using gauges. * Tests charges and replaces batteries. * Inspects parts for wear or reproach or reads work order or schematic drawings to set need repairs. * Cuts and forms insularity and inserts insulant into armature, rotor or stator slots. * Refaces, reams and polishes commutators and railroad car parts to specified adjustments using railcar tools. HEAVY MAINTENANCE ELECTRICALS MAINTENANCE OF MOTORSThe key to minimizing aim chores is schedule routine followup and service. The frequency of routine service varies widely amid applications. Including the pushs in the care schedule for the dictated machine or general plant equipment is ordinarily sufficient. A drive whitethorn require additional or more frequent attention if a breakdown would take in health or safety occupations, severe loss of production, handicap to expensive equipment or other spartan losses. Written records indicating date, items inspected, service performed and take chassis are import ant to an effective routine maintenance program.From such records, detail problems in each application push aside be determine and solved routinely to repress breakdowns and production losses. The routine command and service of process shadow for the most part be done without disconnecting or disassembling the repel. It involves the following factors jacky word and wearing away 1. wash, encounter, vacuum or blow compile diddly-shit from the spue and air passages of the go. disgusting labors run hot when thickly shucks insulates the frame and clogged passages reduce modify system air flow. Heat reduces insulating material conduct and in timetually seduces move ill luck. 2. Feel for air being discharged from the cooling air ports.If the flow is weak or unsteady, cozy air passages are probably clogged. disengage the move from service and faint. 3. Check for signs of corrosion. animation-threatening corrosion whitethorn evidence inner harm and/or a wish for external repainting. Schedule the removal of the repel from service for complete critique and practical rebuilding. 4. In wet or sulphurous environments, uncivil the conduit box and date for deteriorating separation or corroded terminals. Repair as needed. Lubrication Lubricate the aims only when scheduled or if they are noisy or campaign hot.Do NOT over-lubricate. Excessive foulness and oil creates dirt and bottom of the inning violate styles. Heat, go and Vibration Feel the aim frame and bangs for extravaganceive heat or shudder. hear for ab prescript hinderance. All record a possible system also-ran. Promptly key and uproot the source of the heat, noise or frisson. Winding Insulation When records indicate a tendency toward periodic flatus failures in the application, check the fix of the insulation with an insulation resistance test. Such exam is in particular important for gets operated in et or blistering glorys or in broad(prenomina l) close temperatures. Brushes and Commutators (DC rides) 1. Observe the purifyes while the take is running. The spanes essential ride on the commutator smoothly with piffling or no sparking and no face-off noise (chatter). 2. Stop the ride. Be certain(p) that * The clangoures move freely in the toter and the spring tension on each cross is about equal. * Every brush has a clarified move up over the entire working face indicating sound seating. * The commutator is clean, smooth and has a polished cook start where the brushes ride.NOTE everlastingly put each brush back into its original toter. Interchanging brushes decreases switch ability. * There is no grooving of the commutator (small grooves or so the circumference of the commutator). If there is grooving, get hold of the tug from service immediately as this is a symptomatic indication of a very serious problem. 3. Replace the brushes if there is any chance they will non last until the next inspection dat e. 4. If accumulating, clean abroad material from the grooves surrounded by the commutator bars and from the brush holders and posts. 5.Brush sparking, chatter, spendthrift wear or chipping, and a pestering or rough commutator indicate locomote problems requiring prompt service. Figure 1. distinctive DC labor Brushes and Commutator Brushes and Collector go (Synchronous takes) 1. Black spots on the storage battery rings must be take away by rubbing lightly with mulct sandpaper. If non pipd, these spots precedent confront that requires regrinding the rings. Figure 2. Rotary Converter Armature covering Commutator And Slip Rings. 2. An imprint of the brush, signs of arcing or irritable wear indicate the need to remove the push from service and repair or replace the rings. . Check the collector ring brushes as described under Brushes and Commutators. They do non, however, wear as rapidly as commutator brushes. BEARING LUBRICATION Introduction Modern ride designs norma lly provide a open-hearted supply of lubri great dealt in average bearing holds. Lubrication on a scheduled basis, in conformance with the manufacturers recommendations, provides optimum bearing life. Thoroughly clean the lubrication equipment and fittings before lubricating. Dirt introduced into the bearings during lubrication probably causes more bearing failures than the lack of lubrication.Too much poop good deal over pack bearings and cause them to run hot, trim down their life. Excessive lubricant can find its way internal the motor where it collects dirt and causes insulation deterioration. Many small motors are built with permanently lubricated bearings. They cannot and should not be lubricated. OILING SLEEVE BEARINGS As a general rule, fractional horsepower motors with a wick lubrication system should be cover every 2000 seconds of operation or at least annually. Dirty, wet or caustic locations or heavy loading whitethorn require oiling at three-month intervals or more ofttimes.Roughly 30 drops of oil for a 3-inch diam frame to 100 drops for a 9-inch diam frame is sufficient. Use a one hundred fifty SUS viscosity turbine oil or SAE 10 automotive oil. Some large motors are equipped with oil reservoirs and usually a sight gage to check strait-laced level. (Fig. 3) As long as the oil is clean and light in colour, the only requirement is to demand the cavum to the proper level with the oil recommended by the manufacturer. Do not overfill the cavity. If the oil is discoloured, dirty or contains water, remove the drain plug. Flush the bearing with fresh oil until it comes out clean.Coat the plug threads with a sealing compound, replace the plug and fill the cavity to the proper level. When motors are disassembled, sweep the housing with a solvent. Discard utilize felt packing. Replace badly faded bearings. Coat the shaft and bearing approachs with oil and reassemble. Figure 3. Cross separate of the header System of a Large Motor GREA SING BALL AND ROLLER BEARINGS Practically all Reliance ball bearing motors in current production are equipped with the exclusive PLS/Positive Lubrication System. PLS is a procure open-bearing system that provides long, reliable bearing and motor ife regardless of mounting position. Its special internal passages uniformly distribute new skank pumped into the housing during regreasing through the open bearings and forces old shite out through the drain hole. The close running tolerance in the midst of shaft and inner bearing cap minimizes entry of contaminants into the housing and shite migration into the motor. The unique V-groove outer slinger seals the orifice amid the shaft and end bracket while the motor is running or is at rest yet allows relief of grease along the shaft if the drain hole is plugged. Figure 4) The frequency of routine greasing increases with motor size and severity of the application as indicated in Table 1. Actual schedules must be selected by the user f or the specific conditions. During scheduled greasing, remove both the recess and drain plugs. Pump grease into the housing using a standard grease gun and light stuff until clean grease comes out of the drain hole. If the bearings are hot or noisy even after correction of bearing overloads (see Troubleshooting) remove the motor from service. Wash the housing and bearings with a good solvent. Replace bearings that show signs of pervert or wear.Repack the bearings, assemble the motor and fill the grease cavity. Whenever motors are disassembled for service, check the bearing housing. Wipe out any old grease. If there are any signs of grease defilement or breakdown, clean and repack the bearing system as described in the preceding paragraph. Figure 4. Cross Section of PLS Bearing System (Positive Lubrication System) HEAT, NOISE AND thrill Heat Excessive heat is both a cause of motor failure and a sign of other motor problems. The primary damage caused by excess heat is to increase the aging rate of the insulation. Heat beyond the insulations rating nobbleens winding life. aft(prenominal) heat, a motor whitethorn run satisfactorily but its serviceable life will be shorter. For maximum motor life, the cause of overheating should be identified and eliminated. As indicated in the Troubleshooting Sections, overheating results from a variety of different motor problems. They can be grouped as follows * impose on _or_ oppress MOTOR It may be too small or have the faulty starting torque characteristics for the load. This may be the result of poor initial choice or changes in the load requirements. * myopic COOLING Accumulated dirt or poor motor location may prevent the free flow of cooling air more or less the motor.In other cases, the motor may draw heated air from another source. Internal dirt or damage can prevent proper air flow through all sections of the motor. Dirt on the frame may prevent transfer of internal heat to the cooler ambient air. * OVERLOAD ED drive MACHINE Excess loads or jams in the driven machine force the motor to supply grittyer(prenominal)er torque, draw more current and overheat. Table 1. Motor Operating Conditions Motor Horsepower coruscation Duty(1) Standard Duty(2) Heavy Duty(3) Severe Duty(4) Up to 7-1/2 10 to 40 50 to 150 Over 150 10 years 7 years 4 years 1 year 7 years years 1-1/2 years 6 months 4 years 1-1/2 years 9 months 3 months 9 months 4 months 3 months 2 months * flatboat Duty Motors operate infrequently (1 hour/day or less) as in portable floor sanders, valves, door openers. * Standard Duty Motors operate in normal applications (1 or 2 work shifts). Examples imply air conditioning units, conveyors, refrigeration apparatus, washing machinery, woodworking and textile machines, water pumps, machine tools, garage compressors. * Heavy Duty Motors subjected to supra normal operation and vibration (running 24 hours/day, 365 days/year).Such operations as in steel mill service, coal and digging machi nery, motor-generator sets, fans, pumps. * Severe Duty Extremely harsh, dirty motor applications. Severe vibration and in high up spirits ambient conditions much exist. * EXCESSIVE corrasion Misalignment, poor bearings and other problems in the driven machine, power transmission system or motor increase the torque required to drive the loads, raising motor operate temperature. * ELECTRICAL OVERLOADS An electrical failure of a winding or contact in the motor can cause other Windings or the entire motor to overheat. tone and VibrationNoise indicates motor problems but ordinarily does not cause damage. Noise, however, is usually accompanied by vibration. Vibration can cause damage in several ways. It tends to shake windings stateless and mechanically damages insulation by discloseing, flaking or abrading the material. Embrittlement of lead wires from excessive hunting expedition and brush sparking at commutators or current collector rings also results from vibration. Finally , vibration can speed bearing failure by causing balls to brinnell, subdivision bearings to be pounded out of shape or the harness to slack upn in the shells.Whenever noise or vibrations are found in an run motor, the source should be cursorily uninvolved and corrected. What seems to be an evident source of the noise or vibration may be a symptom of a hole-and-corner(a) problem. Therefore, a thorough investigation is often required. Noise and vibrations can be caused by a misaligned motor shaft or can be transmitted to the motor from the driven machine or power transmission system. They can also be the result of either electrical or mechanical derangement in the motor. After checking the motor shaft alignment, disconnect the motor from the driven load.If the motor then operates smoothly, consider for the source of noise or vibration in the driven equipment. If the disconnected motor still vibrates, remove power from the motor. If the vibration stops, look for an electrical derangement. If it continues as the motor coasts without power, look for a mechanical unbalance. galvanic unbalance occurs when the magnetic attraction between stator and rotor is uneven around the periphery of the motor. This causes the shaft to deflect as it rotates creating a mechanical unbalance. galvanizing unbalance usually indicates an electrical failure such as an open tator or rotor winding, an open bar or ring in squirrel coop motors or shorted subject field coils in synchronous motors. An uneven air gap, usually from badly worn sleeve bearings, also produces electrical unbalance. The chief causes of mechanical unbalance include a malformed mounting, bent shaft, poorly balanced rotor, open(a) parts on the rotor or bad bearings. Noise can also come from the fan hitting the frame, shroud, or foreign objects inside the shroud. If the bearings are bad, as indicated by excessive bearing noise, determine why the bearings failed.Brush chatter is a motor noise that can be c aused by vibration or other problems unrelated to vibration. WINDINGS Care of Windings and Insulation Except for expensive, high horsepower motors, routine inspections generally do not involve opening the motor to inspect the windings. Therefore, long motor life requires selection of the proper enclosure to protect the windings from excessive dirt, abradants, moisture, oil and chemicals. When the need is indicated by severe direct conditions or a history of winding failures, routine testing can depict deteriorating insulation.Such motors can be take away from service and repaired before out of the blue(predicate) failures stop production. Whenever a motor is candid for repair, service the windings as follows 1. Accumulated dirt prevents proper cooling and may put one over moisture and other contaminants that damage the insulation. nihility the dirt from the windings and internal air passages. Do not use high pressure air because this can damage windings by driving the dirt into the insulation. 2. Abrasive dust drawn through the motor can abrade coil noses, removing insulation. If such scratching is found, the winding should be revarnished or replaced. . moisture reduces the dielectric strength of insulation which results in swindle. If the inside of the motor is damp, dry the motor per tuition in Cleaning and Drying Windings. 4. Wipe any oil and grease from inside the motor. Use care with solvents that can combat the insulation. 5. If the insulation appears brittle, overheated or cracked, the motor should be revarnished or, with severe conditions, rewound. 6. Loose coils and leads can move with changing magnetic handle or vibration, causing the insulation to wear, crack or fray. Revarnishing and retying leads may correct venial problems.If the rid coil situation is severe, the motor must be rewound. 7. Check the lead-to-coil connections for signs of overheating or corrosion. These connections are often undecided on large motors but taped on small motors. Repair as needed. 8. Check wound rotor windings as described for stator windings. Because rotor windings must withstand centrifugal forces, tightness is even more important. In addition, check for loose pole pieces or other loose parts that create unbalance problems. 9. The whorl rotor rods and end rings of squirrel cage motors rarely need attention.However, open or broken rods create electrical unbalance that increases with the number of rods broken. An open end ring causes severe vibration and noise. TESTING WINDINGS rule field testing of windings can identify deteriorating insulation permitting scheduled repair or replacement of the motor before its failure disrupts operations. Such testing is good behave especially for applications with severe in operation(p) conditions or a history of winding failures and for expensive, high horsepower motors and locations where failures can cause health and safety problems or high economical loss.The easiest field test that prevents the most failures is the ground-insulation or 127 megger test. It applies DC voltage, usually 500 or 1000 volts, to the motor and measures the resistance of the insulation. NEMA standards require a minimum resistance to ground at 40 scores C ambient of 1 mega ohm per kv of rating improver 1 mega ohm. Medium size motors in good condition will generally have mega ohmmeter interprets in excess of 50 mega ohms. Low readings may indicate a seriously reduced insulation condition caused by contamination from moisture, oil or conductive dirt or deterioration from age or excessive heat.One megger reading for a motor means little. A curve recording resistance, with the motor refrigerant and hot, and date indicates the rate of deterioration. This curve provides the information needed to decide if the motor can be safely left in service until the next scheduled inspection time. The megger test indicates ground insulation condition. It does not, however, measure turn-to-turn insulat ion condition and may not pick up localized weaknesses. Moreover, operating voltage peaks may stress the insulation more severely than megger voltage.Experience and conditions may indicate the need for additional routine testing. A test used to prove existence of a safety margin above operating voltage is the AC high potential ground test. It applies a high AC voltage (typically, 65% of a voltage times twice the operating voltage plus 1000 volts) between windings and frame. Although this test does detect poor insulation condition, the high voltage can arc to ground, burning insulation and frame, and can also actually cause failure during the test. It should never be applied to a motor with a low megger reading.DC rather than AC high potential tests are beseeming popular because the test equipment is smaller and the low test current is less suicidal to people and does not create damage of its own. CLEANING AND DRYING WINDINGS Motors which have been flooded or which have low megger readings because of contamination by moisture, oil or conductive dust should be thoroughly cleaned and dried. The methods depend upon unattached equipment. A hot water hose and detergents are commonly used to remove dirt, oil, dust or salt concentrations from rotors, stators and connection boxes.After cleaning, the windings must be dried, commonly in a forced-draft oven. Time to obtain refreshing megger readings varies from a couple hours to a hardly a(prenominal) days. BRUSH AND COMMUTATOR CARE Some maintenance people with some relatively untroubled AC squirrel cage motors forget that brushes and commutators require more frequent routine inspection and service. The result can be gratuitous failures between scheduled maintenance. Many factors are involved in brush and commutator problems. All generally involve brush sparking usually accompanied by chatter and often excessive wear or chipping.Sparking may result from poor commutator conditions or it may cause them. The degree o f sparking should be intractable by careful visual inspection. The illustrations shown in Fig. 5 are a useful guide. It is very important that you gauge the degree number as accurately as possible. The solution to the problem may well depend upon the accuracy of your answer since many motor, load, environmental and application conditions can cause sparking. It is also imperative that a exempt be determined as quickly as possible. Sparking generally feeds upon itself and becomes worse with time until serious damage results.Some of the causes are self-explanatory and some are not. Some are constant and others intermittent. Therefore, eliminating brush sparking, especially when it is a chronic or recurring problem, requires a thorough review of the motor and operating conditions. Always recheck for sparking after correcting one problem to see that it solved the total problem. in addition remember that, after grinding the commutator and decently reseating the brushes, sparking will occur until the polished, brown surface reforms on the commutator. Figure 5. Degrees of Generator and Motor SparkingNOTE Small sparks are yellow in colour, and the large sparks are white in colour. The white sparks, or blue-white sparks, are most detrimental to commutation (both brush and commutator). maiden consider external conditions that affect commutation. back up motor overloads, vibration and high humidity cause sparking. Extremely low humidity allows brushes to wear through the needed polished brown commutator surface film. Oil, paint, acid and other chemical vapours in the atmosphere contaminate brushes and the commutator surface. see to it for obvious brush and brush holder deficiencies 1.Be sure brushes are properly seated, move freely in the holders and are not too short. 2. The brush spring pressure must be equal on all brushes. 3. Be sure spring pressure is not too light or too high. Large motors with adjustable springs should be set at about 3 to 4 pounds per sq uare inch of brush surface in contact with the commutators. 4. Remove dust that can cause a short between brush holders and frame. 5. Check lead connections to the brush holders. Loose connections cause overheating. Look for obvious commutator problems 1. Any condition other than a polished, brown surface under the brushes indicates a problem.Severe sparking causes a rough pitch-black surface. An oil film, paint spray, chemical contamination and other abnormal conditions can cause a blackened or discolored surface and sparking. Streaking or grooving under only some brushes or flat and burned-out spots can result from a load mismatch and cause motor electrical problems. Grooved commutators should be removed from service. A brassy appearance shows excessive wear on the surface resulting from low humidity or wrong brush tell. 2. High mica or high or low commutator bars make the brushes jump, causing sparking. 3.Carbon dust, copper foil or other conductive dust in the slots between c ommutator bars causes shorting and sometimes sparking between bars. If correcting any obvious deficiencies does not eliminate sparking or noise, look to the less obvious possibilities 1. If brushes were changed before the problem became apparent, check the grade of brushes. Weak brushes may chip. Soft, low abrasive brushes may allow a thick film to form. High friction or high abrasion brushes wear away the brown film, producing a brassy surface. If the problem appears only under one or more of the brushes, two different grades of brushes may have been installed.Generally, use only the brushes recommended by the motor manufacturer or a qualified brush expert. 2. The brush holder may have been reset improperly. If the boxes are more than 1/8&8243 from the commutator, the brushes can jump or chip. Setting the brush holder off neutral causes sparking. ordinarily the brushes must be equally disjointed around the commutator and must be repeat to the bars so all make contact with each b ar at the same time. 3. An eccentric commutator causes sparking and may cause vibration. Normally, concentricity should be within . 001&8243 on high speed, . 002&8243 on medium speed and . 04&8243 on slow speed motors. 4. Various electrical failures in the motor windings or connections endorse themselves in sparking and poor commutation. Look for goldbrick or opens in the armature circuit and for grounds, shorts or opens in the field winding circuits. A weak interpole circuit or large air gap also generate brush sparking. SAFETY cam stroke in industrial sector defines any incident which has potential to cause blur to human, loss of property and damage to environment. Causes for item of accident * grievous Act * Unsafe Conditions Hazards * Conditions prevailing in work place finally leading to accidents.Types * Mechanical * Electrical * Chemical * Environmental Precautions * Look knock * Watch steps * Wear tog and helmets * Take care of the flow opening * Avoid lose clothing * Always carry your I-D card CONCLUSION In this project, I have studied the working of electrical repair shop and about the function of Bhilai steel plant. I have obtained some knowledge about * roller mill * Blast furnace * Electrical repair shop * Motor windings BIBLIOGRAPHY NOTES TAKEN DURING THE raise OF THE VOCATIONAL TRANING INTERNET www. google. com INTRANRT SAIL, BSP INTRANET SITE