INDUSTRIAL TRAININORT

INTRODUCTION Indian Railways is the state-owned railway company of India. It comes under the Ministry of Railways. Indian Railways has one of the largest and busiest rail networks in the world, transporting over 18 million passengers and more than 2 million tonnes of freight daily. Its revenue is Rs.107.66 billion. It is the world's largest commercial employer, with more than 1.4million employees. It operates rail transport on 6,909 stations over a total route length of more than 63,327kilometres (39,350miles).The fleet of Indian railway includes over 200,000 (freight) wagons, 50,000 coaches and 8,000 locomotives. It also owns locomotive and coach production facilities. It was founded in 1853 under the East India Company. Indian Railways is administered by the Railway Board. Indian Railways is divided into 16 zones. Each zone railway is made up of a certain number of divisions. There are a total of sixty-seven divisions. It also operates the Kolkata metro. There are six manufacturing plants of the Indian Railways. The history of rail transport in India began in the mid-nineteenth century. The core of the pressure for building Railways In India came from London. In 1848, there was not a single kilometre of railway line in India. The country's first railway, built by theGreat Indian Peninsula Railway(GIPR), opened in 1853, between Bombay and Thane. A British engineer,Robert Maitland Brereton, was responsible for the expansion of the railways from 1857 onwards. The Allahabad-Jabalpur branch line of theEast Indian Railwayhad been opened in June 1867. Brereton was responsible for linking this with the GIPR, resulting in a combined network of 6,400km (4,000mi). Hence it became possible to travel directly fromBombaytoCalcutta. This route was officially opened on 7 March 1870 and it was part of the inspiration for French writerJules Verne's bookAround the World in Eighty Days. At the opening ceremony, the Viceroy Lord Mayo concluded that"it was thought desirable that, if possible, at the earliest possible moment, the whole country should be covered with a network of lines in a uniform system".By 1875, about 95 million were invested by British companies in India. Guaranteed railways.[6]By 1880 the network had a route mileage of about 14,500km (9,000mi).CLASSIFICATION 1. Standard Gauge designations and dimensions:- W = Broad gauge (1.67 m) Y = Medium gauge ( 1 m) Z = Narrow gauge ( 0.762 m) N = Narrow gauge ( 0.610 m)2. Type of Traction designations:- D = Diesel-electric traction C = DC traction A = AC traction CA=Dual power AC/DC traction3. The type of load or Service designations:- M= Mixed service P = Passenger G= Goods S = Shunting4. Horse power designations from June 2002 (except WDP-1 & WDM-2 LOCOS) 3 For 3000 horsepower 4 For 4000 horsepower 5 For 5000 horsepower A For extra 100 horsepower B For extra 200 horsepower and so on.Hence WDM-3A indicates a broad gauge loco with diesel-electric traction. It is for mixed services and has 3100 horsepower.

FUEL SECTION

The section is concern with receiving, storage and refilling of diesel and lube oil. It has 3 large storage tanks and one underground tank for diesel storage which have a combined storage capacity of 10,60, 000 liters.This stock is enough to end for 15-16 days The fuel is supplied by truck from IOC - Panipat refinery each truck diesel sample is treated in diesel lab and after it in unloaded. Sample check is necessary to avoid water, kerosene mixing diesel. Two fuel filling points are established near the control room It also handles the Cardiam compound , lube oil. diesel is only for loco use if the diesel samples are not according to the standard , the delivery of the fuel is rejected. Viscosity of lube oil should be 100-1435 CST. Water mixing reduces the viscosity. The fuel filling points are established near the control room It also handles the Cardiam compound , lube oil. diesel is only for loco use if the diesel samples are not according to the standard , the delivery of the fuel is rejected. Viscosity of lube oil should be 100-1435 CST. Water mixing reduces the viscosity. HSD high speed diesel is used as fuel in loco and some lube oil of different lind are also used in different parts of loco. All locomotive have individual fuel oil system. The fuel oil system is designed to introduce fuel oil into the engine cylinders at the correct time, at correct pressure, at correct quantity and correctly atomized. The system injects into the cylinder correctly metered amount of fuel in highly atomized form. High pressure of fuel is required to lift the nozzle valve and for better penetration of fuel into the combustion chamber. High pressure also helps in proper atomization so that the small droplets come in better contact with the compressed air in the combustion chamber, resulting in better combustion engine with variable requirement of fuel. Time of fuel injection is also important for better combustion. One branch line from the lubricating system of the engine is connected to the turbo- supercharger. Oil from the lube oils system circulated through the turbo- supercharger for lubrication of its bearings. After the lubrication is over, the oil returns back to the lube oil system through a return pipe. Oil seals are provided on both the turbine and blower ends of the bearings to prevent oil leakage to the blower or the turbine housing. TURBO SUPERCHARGER

INTRODUCTION The diesel engine produces mechanical energy by converting heat energy derived from burning of fuel inside the cylinder. For efficient burning of fuel, availability of sufficient air in proper ratio is a prerequisite. In a naturally aspirated engine, during the suction stroke, air is being sucked into the cylinder from the atmosphere. The volume of air thus drawn into the cylinder through restricted inlet valve passage, within a limited time would also be limited and at a pressure slightly less than the atmosphere. The availability of less quantity of air of low density inside the cylinder would limit the scope of burning of fuel. Hence mechanical power produced in the cylinder is also limited. A Turbocharger, or Turbo, is a gas compressor used for forced-induction of an internal combustion engine. Like a supercharger, the purpose of a turbocharger is to increase the density of air entering the engine to create more power. However, a turbocharger differs in that the compressor is powered by a turbine driven by the engine's own exhaust gases.TURBO SUPERCHARGER AND ITS WORKING PRINCIPLE The exhaust gas discharge from all the cylinders accumulate in the common exhaust manifold at the end of which, turbo- supercharger is fitted. The gas under pressure there after enters the turbo- supercharger through the torpedo shaped bell mouth connector and then passes through the fixed nozzle ring. Then it is directed on the turbine blades at increased pressure and at the most suitable angle to achieve rotary motion of the turbine at maximum efficiency. After rotating the turbine, the exhaust gas goes out to the atmosphere through the exhaust chimney. The turbine has a centrifugal blower mounted at the other end of the same shaft and the rotation of the turbine drives the blower at the same speed. The engine initially starts as naturally aspirated engine. With the increased quantity of fuel injection increases the exhaust gas pressure on the turbine. Thus the self-adjusting system maintains a proper air and fuel ratio under all speed and load conditions of the engine on its own. The maximum rotational speed of the turbine is 18000/22000 rpm for the Turbo supercharger and creates max. Of 1.8 kg/cm2 air pressure in air manifold of diesel engine, known as Booster Air Pressure (BAP). Low booster pressure causes black smoke due to incomplete combustion of fuel. High exhaust gas temperature due to after burning of fuel may result in considerable damage to the turbo supercharger and other component in the engine.MAIN COMPONENTS OF TURBO-SUPERCHARGERTurbo- supercharger consists of following main components. Gas inlet casing. Turbine casing. Intermediate casing Blower casing with diffuser Rotor assembly with turbine and rotor on the same shaft.

ROTOR ASSEMBLY The rotor assembly consists of rotor shaft, rotor blades, thrust collar, impeller, inducer, centre studs, nosepiece, locknut etc. assembled together. The rotor blades are fitted into fir tree slots, and locked by tab lock washers.

LUBRICATING, COOLING AND AIR CUSHIONING

LUBRICATING SYSTEM : One branch line from the lubricating system of the engine is connected to the turbo- supercharger. Oil from the lube oils system circulated through the turbo- supercharger for lubrication of its bearings. After the lubrication is over, the oil returns back to the lube oil system through a return pipe. Oil seals are provided on both the turbine and blower ends of the bearings to prevent oil leakage to the blower or the turbine housing. COOLING SYSTEM The cooling system is integral to the water cooling system of the engine. Circulation of water takes place through the intermediate casing and the turbine casing, which are in contact with hot exhaust gases. The cooling water after being circulated through the turbo- supercharger returns back again to the cooling system of the locomotive.

AFTER COOLER It is a simple radiator, which cools the air to increase its density. Scales formation on the tubes, both internally and externally, or choking of the tubes can reduce heat transfer capacity. This can also reduce the flow of air through it. This reduces the efficiency of the diesel engine. ADVANTAGES OF SUPER CHARGED ENGINES A super charged engine can produce 50 percent or more power than a naturally aspirated engine. The power to weight ratio in such a case is much more favorable.Better scavenging in the cylinders. This ensures carbon free cylinders and valves, and better health for the engine also.Better ignition due to higher temperature developed by higher compression in the cylinder. FUEL OIL SEYSTEM

INTRODUCTION All locomotive have individual fuel oil system. The fuel oil system is designed to introduce fuel oil into the engine cylinders at the correct time, at correct pressure, at correct quantity and correctly atomized. The system injects into the cylinder correctly metered amount of fuel in highly atomized form. High pressure of fuel is required to lift the nozzle valve and for better penetration of fuel into the combustion chamber. High pressure also helps in proper atomization so that the small droplets come in better contact with the compressed air in the combustion chamber, resulting in better combustion engine with variable requirement of fuel. Time of fuel injection is also important for better combustion.

FUEL OIL SYSTEM The fuel oil system consists of two integrated systems. These are- FUEL INJECTION PUMP (F.I.P). FUEL INJECTION SYSTEM.

FUEL INJECTION PUMP It is a constant stroke plunger type pump with variable quantity of fuel delivery to suit the demands of the engine. The fuel cam controls the pumping stroke of the plunger. The length of the stroke of the plunger and the time of the stroke is dependent on the cam angle and cam profile, and the plunger spring controls the return stroke of the plunger. The plunger moves inside the barrel, which has very close tolerances with the plunger. When the plunger reaches to the BDC, spill ports in the barrel, which are connected to the fuel feed system, open up. Oil then fills up the empty space inside the barrel. At the correct time in the diesel cycle, the fuel cam pushes the plunger forward.FUEL INJECTION NOZZLE The fuel injection nozzle or the fuel injector is fitted in the cylinder head with its tip projected inside the combustion chamber. It remains connected to the respective fuel injection pump with a steel tube known as fuel high pressure line. The fuel injection nozzle is of multi-hole needle valve type operating against spring tension. The needle valve closes the oil holes by blocking the oil holes due to spring pressure. Proper angle on the valve and the valve seat, and perfect bearing ensures proper closing of the valve.SPRAY PRESSURE The stipulated correct pressure at which the spray should take place 3900-4050 psi for new and 3700-3800 psi for reconditioned nozzles. If the pressure is down to 3600 psi the nozzle needs replacement. The spray pressure is indicated in the gauge provided in the test machine. Shims are being used to increase or decrease the tension of nozzle spring which increases or decreases the spray pressure

FUEL INJECTION NOZZLE TEST

The criteria of a good nozzle are good atomization, correct spray pattern and no leakage or dribbling. Before a nozzle is put to test the assembly must be rinsed in fuel oil, nozzle holes cleaned with wire brush and spray holes cleaned with steel wire of correct thickness. The fuel injection nozzles are tested on a specially designed test stand, where the following tests are conducted.

SPRAY PATTERN

Spray of fuel should take place through all the holes uniformly and properly atomized. While the atomization can be seen through the glass jar, an impression taken on a sheet of blotting paper at a distance of 1 to 1 1/2 inch also gives a clear impression of the spray pattern.

BOGIE INTRODUCTION A bogie is a wheeled wagon or trolley. In mechanics terms, a bogie is a chassis or framework carrying wheels, attached to a vehicle. It can be fixed in place, as on a cargo truck, mounted on a swivel, as on a railway carriage or locomotive, or sprung as in the suspension of a caterpillar tracked vehicle. Bogies serve a number of purposes:- To support the rail vehicle body To run stably on both straight and curved track To ensure ride comfort by absorbing vibration, and minimizing centrifugal forces when the train runs on curves at high speed. To minimize generation of track irregularities and rail abrasion. .. .CLASSIFICATION OF BOGIE Bogie is classified into the various types described below according to their configuration in terms of the number of axle, and the design and structure of the suspension. According to UIC classification two types of bogie in Indian Railway are:- Bo-Bo Co-Co A Bo-Bo is a locomotive with two independent four-wheeled bogies with all axles powered by individual traction motors. Co-Co is a code for a locomotive wheel arrangement with two six-wheeled bogies with all axles powered, with a separate motor per axle. EXPRESSOR INTRODUCTION In Indian Railways, the trains normally work on vacuum brakes and the diesel locos on air brakes. As such provision has been made on every diesel loco for both vacuum and compressed air for operation of the system as a combination brake system for simultaneous application on locomotive and train . In ALCO locos the exhauster and the compressor are combined into one unit and it is known as EXPRESSOR. It creates 23" of vacuum in the train pipe and 140 PSI air pressure in the reservoir for operating the brake system and use in the control system etc.The expresser is located at the free end of the engine block and driven through the extension shaft attached to the engine crank shaft. The two are coupled together by fast coupling (Kopper's coupling). Naturally the expresser crank shaft has eight speeds like the engine crank shaft. There are two types of expresser are, 6CD, 4UC & 6CD, 3UC. In 6CD,4UC expresser there are six cylinder and four exhauster whereas 6CD,3UC contain six cylinder and three exhauster.WORKING OF EXHAUSTER Air from vacuum train pipe is drawn into the exhauster cylinders through the open inlet valves in the cylinder heads during its suction stroke. Each of the exhauster cylinders has one or two inlet valves and two discharge valves in the cylinder head. A study of the inlet and discharge valves as given in a separate diagram would indicate that individual components like (1) plate valve outer (2) plate valve inner (3) spring outer (4) spring inner etc. are all interchangeable parts. Only basic difference is that they are arranged in the reverse manner in the valve assemblies which may also have different size and shape. The retainer stud in both the assemblies must project upward to avoid hitting the piston. The pressure differential between the available pressure in the vacuum train pipe and inside the exhauster cylinder opens the inlet valve and air is drawn into the cylinder from train pipe during suction stroke. In the next stroke of the piston the air is compressed and forced out through the discharge valve while the inlet valve remains closed. The differential air pressure also automatically opens or closes the discharge valves, the same way as the inlet valves operate. This process of suction of air from the train pipe continues to create required amount of vacuum and discharge the same air to atmosphere. The VA-1 control valve helps in maintaining the vacuum to requisite level despite continued working of the exhauster.Compressor The compressor is a two stage compressor with one low pressure cylinder and one high pressure cylinder. During the first stage of compression it is done in the low pressure cylinder where suction is through a wire mesh filter. After compression in the LP cylinder air is delivered into the discharge manifold at a pressure of 30 / 35 PSI. Workings of the inlet and exhaust valves are similar to that of exhauster which automatically open or close under differential air pressure. For inter-cooling air is then passed through a radiator known as inter-cooler. This is an air to air cooler where compressed air passes through the element tubes and cool atmospheric air is blown on the outside fins by a fan fitted on the expressor

AIR BRAKES

INTRODUCTION An air brake is a conveyance braking system actuated by compressed air. Modern trains rely upon a fail preventive air brake system that is based upon a design patented by George Westinghouse on March 5,1872. In the air brake's simplest form, called the straight air system, compressed air pushes on a piston in a cylinder. The piston is connected through mechanical linkage to brake shoes that can rub on the train wheels, using the resulting friction to slow the train.AIR BRAKE SYSTEM OPERATION The compressor in the locomotive produces the air supplied to the system. It is stored in the main reservoir. Regulated pressure of 6 kg/cm2 flows to the feed pipe through feed valve and 5-kg/cm2 pressure by drivers brake valve to the brake pipe. The feed pipe through check valve charges air reservoir via isolating cock and also by brake pipe through distributor valve. The brake pipe pressure controls the distributor valves of all the coaches/wagons which in turn control the flow of compressed air from Air reservoir to break cylinder in application and from brake cylinder to atmosphere in release.During application, the driver in the loco lowers the BP pressure. This brake pipe pressure reduction causes opening of brake cylinder inlet passage and simultaneously closing of brake cylinder outlet passage of the distributor valve. In this situation, auxiliary reservoir supplies air to brake cylinder. At application time, pressure in the brake cylinder and other brake characteristics are controlled by distributor valve.

CYLINDER HEAD

INTRODUCTION The cylinder head is held on to the cylinder liner by seven hold down studs or bolts provided on the cylinder block. It is subjected to high shock stress and combustion temperature at the lower face, which forms a part of combustion chamber. It is a complicated casting where cooling passages are cored for holding water for cooling the cylinder head. In addition to this provision is made for providing passage of inlet air and exhaust gas. Further, space has been provided for holding fuel injection nozzles, valve guides and valve seat inserts also.Components of cylinder head In cylinder heads valve seat inserts with lock rings are used as replaceable wearing part. The inserts are made of stellite or weltite. To provide interference fit, inserts are frozen in ice and cylinder head is heated to bring about a temperature differential of 250F and the insert is pushed into recess in cylinder head. The valve seat inserts are ground to an angle of 44.5 whereas the valve is ground to 45 to ensure line contact. (In the latest engines the inlet valves are ground at 30 and seats are ground at 29.5). Each cylinder has 2 exhaust and 2 inlet valves of 2.85" in dia. The valves have stem of alloy steel and valve head of austenitic stainless steel, butt-welded together into a composite unit. The valve head material being austenitic steel has high level of stretch resistance and is capable of hardening above Rockwell- 34 to resist deformation due to continuous pounding action.

SCHEDULE EXAMINATION

INTRODUCTION The railway traffic requires safety and reliability of service of all railway vehicles. Suitable technical systems and working methods adapted to it, which meet the requirements on safety and good order of traffic should be maintained. For detection of defects, non-destructive testing methods - which should be quick, reliable and cost-effective - are most often used. Inspection of characteristic parts is carried out periodically in accordance with internal standards or regulations; inspections may be both regular and extraordinary; the latter should be carried out after collisions, derailment or grazing of railway vehicles.Maintenance of railway vehicles is scheduled in accordance with periodic inspections and regular repairs. Inspections and repairs are prescribed according to the criteria of operational life, limited by the time of operation of a locomotive in traffic or according to the criteria of operational life including the path traveled. For the proper functioning of diesel shed and to reduce the number of failures of diesel locos, there is a fixed plan for every loco, at the end of which the loco is checked and repaired. This process is called scheduling. There are two types of schedules which are as follows:- Major schedules Minor scheduleMINOR SCHEDULES Schedule is done by the technicians when the loco enters the shed. After 15 days there is a minor schedule. The following steps are done every minor schedule & known as SUPER CHECKING. The lube oil level & pressure in the sump is checked. The coolant water level & pressure in the reservoir is checked. The joints of pipes & fittings are checked for leakage. The check super charger, compressor & its working. The engine is checked thoroughly for the abnormal sounds if there is any. F.I.P. is checked properly by adjusting different rack movements.MAJOR SCHEDULES These schedules include M-4, M-8 M-12 and M-24. The M-4 schedule is carried out for 4 months and repeated after 20 months. The M-8 schedule is carried out for 8 months and repeated after 16 months. The M-12 is an annual schedule whereas the M-24 is two years. Besides all of these schedules for the works that are not handled by the schedules there is an out of course section, which performs woks that are found in inspection and are necessary. As any Locomotive arrives in the running section first of all the driver diary is checked which contains information about the locomotive parameters and problem faced during operation. The parameters are Booster air pressure (BAP), Fuel oil pressure (FOP), Lubricating oil pressure (LOP) and Lubricating oil consumption (LOC). After getting an idea of the initial problems from the drivers diary the T-1 schedule is made for inspection and minor repairs.

YEARLY MECHANICAL In this section, major schedules such as M-24, M48 and M-72 are carried out. Here, complete overhauling of the locomotives is done and all the parts are sent to the respective section and new parts are installed after which load test is done to check proper working of the parts. The work done in these sections are as follows:1). Repeating of all items of trip, quarterly and monthly schedule.2). Testing of all valves of vacuum/compressed air system. Repair if necessary.3). Replacement of coalesce element of air dryer.4). Reconditioning, calibration and checking of timing of FIP is done. Injector is overhauled.5). Cleaning of Bull gear and overhauling of gear-case is done. 6).RDP testing of radiator fan, greasing of bearing, checking of shaft and keyway. Examination of coupling and backlash checking of gear unit is done.7). Checking of push rod and rocker arm assembly. Replacement is done if bent or broken. Checking of clearance of inlet and exhaust valve.8). Examination of piston for cracks, renew bearing shell of connecting rod fitment. Checking of connecting rod elongation.9). Checking of crankshaft thrust and deflection. Shims are added if deflection is more then the tolerance limit.10). Main bearing is discarded if it has embedded dust, gives evidence of fatigue failure or is weared . 11). Checking of cracks in water header and elbow. Install new gaskets in the air intake manifold. Overhauling of exhaust manifold is done.12). Checking of cracks in crankcase, lube oil header, jumper and tube leakage in lube oil cooler. Replace or dummy of tubes is done.13). Lube oil system- Overhauling of pressure regulating valves, by pass valve, lube oil filters and strainers is done. Additional items for WDP2 locos:-Checking for cracks bogie frame and bolster. Checking of hydraulic dampers for oil leakage. Check coil spring for free height. Zyglo test of guide link bolts is performed. Examination of taper roller bearing for their condition and clearance is done. Check and change center pivot liners. Checking of tightness of nuts on brake head pin. Disassembly, cleaning, greasing, repairing, replacement of brake cylinder parts is done. Ultrasonic test of axles is performed. Visual Examination of suspension springs for crack and breakage. Checking of free and working height of spring. Inspection of bull gear for any visible damage is done and the teeth profile is checked. Test loco on load box as per RDSO standards.14