15-12-2012, 11:29 AM
TRAINING REPORT ON INSULATION AND MANUFACTURING PROCESS OF 500MW TURBO GENERATOR BARS
MANUFACTURING PROCESS.docx (Size: 668.16 KB / Downloads: 81)
COMPANY PROFILE
The first plant of what is today known as BHEL was established nearly 40 yearsago at BHOPAL and was genius of heavy electrical equipment industry in India. BHELis today the largest engineering enterprise of its kind in India with well recognized track records of performance making profits continuously since 1971-72 it achieved a salesturnover of 1023 crore in 1977-78. BHEL caters to core sectors of the Indian economy in power, industry, transportation,defense etc.
The wide network of BHEL is 14 manufacturing divisions, 9 service centers& 4 power global players.Power sector comprises thermal, nuclear, gas & hydro power plant businesstoday, BHEL supplied sets account for nearly 56, 318 MW or 65% of the total installedcapacity of 86, 636 MW in as against nit till 1969-70.BHEL has proven turnkey capabilities for executing power projectors fromconcept to commissioning. It possess the technology and capability to produce thermal power plant equipments up to 1000 MW rating and gas turbine generator sets up to a unitrating of 240 MW. Cogeneration and combines cycle plants has been introduced toacheve higher plant efficencies. To make efficient use of the higher ash content coilmanufacturers 235 MW nuclear turbine generator sets and has commenced production of 500 MW nuclear turbine generator head discharge combinations are also engineered and manufactured is also competitive.
Transmission:
BHEL also supplies a wide range of transmission products and system up to 400KV class. These include high voltage power and distribution transformer, instrumenttransformers, instrument, transformers, dry type transformers. SF6 switch gear, capacitor and insulator etc series and shunt compensation system have been also developed andintroduced to minimize transmission losses.
Transportations:
A high percentage of trains operated by Indian Railway are equipped withBHEL is traction and traction control equipments including the metro at Calcutta anddelhi. The company supplies broad gauge.Electrical locomotive to Indian railway and diesel shunting locomotives to variousindustries 5000/6000 hp ac/dc locomotive developed and manufactured by BHEL have been leased to Indian railway, battery powered road.
International operations:
BHEL is product series and projects have been exported to over so countriesranging from UNITED STATES in the west to NEW ZEALAND in for east INDIA isover 3000 MW. A few motable ones are 150 MW gas turbine to GERMANY, utility boiler and open cycle gas turbine plant to MALAYSIA, Tripoli west, power station inLibya and Turkey. In Cyprus, hydro generator to New Zealand and hydro power plant toThailand , Saudi Arabia, Oman , Greece and Egypt.
BHEL-AN OVERVIEW
BHEL is the largest engineering and manufacturing enterprise in India in theenergy related sector. BHEL was established more than 40 years ago, ushering in theindigenous Heavy Electrical Equipment industry in India, a dream which has been morethan released with a well-recognized track record of performance.BHEL caters to core sectors of the India economy viz. Power Generation andTransmission, Renewable Energy, Defence etc. The wide network of BHEL is 14manufacturing divisions, 4 power sector regional centers, 8 service centers, 15 regionaloffices and a large number of Projects sites spread all over India and abroad enables thecompany to promptly serve its customer and provide them with suaitableproducts,systems and services- efficiently and at competitive prices.BHEL has attained ISO 9001 certification for quality management and all themanufacturing units/divisions of BHEL have been upgraded to the latest ISO 9001:2000version. All the major units/divisions of BHEL have been awarded ISO 14001certification for Environmental Management System and OHSAS-18001 certification for Occupational Health and Safety management System. BHEL become the first PublicSector Company in the country to win the coveted ³PRIZE´ for its Haridwar unit under the CII Exim Award for business excellence as per the globally recognized model of European Foundation for Quality Management. BHEL is the only PSU among the 12Indian Companies to figure in ³Forbes Asia Fabulous 50´ list. It has also won the³Business Standard Star Public Sector Company Award 2006´. The company receivedMoU Excellence Award for 2004-2005 and Merit Certificate for MoU Excellence for 2005-2006.
Power Generation:
Power generation Sector comprises Thermal Gas, Hydrogen, Nuclear power plant business. As of 31.3.2007. BHEL supplied sets accounts for 80,781 MW or nearly 65% of the total install capacity of 1, 25,414 MW in the country.Significantly these sets contribute 73% of the total power generated in the country.
Heavy Electrical Equipment Plant:
BHEL's Heavy ElectricalEquipment Plant (HEEP) was set up in technical collaboration with USSR, for themanufacturing of power plant equipment, AC/DC motors of various rating withassociated control equipment and started production in January 1967. In 1976, BHELentered into a collaboration agreement with M/s Kraftwerk Union, AG of Germany for design, manufacturing, erection and commissioning of large size steam turbines. Morethan 40 percent of the country's electrical energy is generated from the power equipmentsupplied by BHEL, Haridwar. The products, which are manufactured in HEEP, are: -Steam Turbines, Turbo Generators, hydro turbines, Gas turbines, etc.
Transposition:
Transposition means changing/shifting of position of each conductor in activecore(slot) part. After cutting the required number of conductors, the conductorsarearranged on the 12 comb in staggered manner and then bends are given to the conductorswith the help of bending die at required distance. Then the conductors are taken out fromthe comb and die and placed with their ends in a line and transposition is carried out.
This process is repeated for making another half of the bar which would be mirror image of the first half. The two halves of the bar are overlapped over each other and aspacer is placed between the two halves.1. To reduce eddy current losses.2. Equalize the voltage generator.3. To minimize skin effect of ac current, small cross section of conductor is usedan also hollow conductors are used to effect cooling by D.M.water
Crossover insulation:
The pre insulation of the copper conductor may get damaged due to mechanical bending in die during transposition, hence the insulating spacers are provided at thecrossover portion of the conductors. A filler material (insulating putty of moldingmicanite) is provided along the height of the bar to maintain the rectangular shape and tocover the difference of level of conductors. To eliminate inter turn short at bends duringedge wise bending and leveling of bars in slots portion for proper stack pressing
Stack Pressing:
This process is basically done to consolidate the solid as well as the hollowconductors into a single bar. In this process the bar is pressed both vertically andhorizontally in the Pressing Machine. The pressing machines are also provided with theheaters Each bar is loaded on each tier of heating plate and it is then provided with aninitial pressure of 355 kg per cm2 and an initial temperature of 100-110° C. then thetemperature is allowed to raise to the maximum of 160°C, this temperature is kept for atleast one hour with a final pressure of 8010 kg per cm2 vertically and 7010 kg per cm2horizontally.
After pressing the bar at specified pressure and maximum temperature for onehour, the bars are then cooled placing them on cooling plates through which water isallowed to follow below 50°C. Then the ends of both the bars are cleaned with rectifiedspirit and sand paper for the inter strand test.