This shed was set up in Feb. 1976 by Railway Electrification Organization as a part of Tundla – Delhi electrification scheme and was designed to home 50 electric locomotives at an initial cost of 1. 5 crore. The prime objective of setting up this shed was to maintain Electric locomotives required for hauling important mail/express trains on Delhi – Howrah section. The initial holding of the shed was 34, all of which were WAM4. At present, holding has increased to 138 and this includes 16 State-of-the-Art Technology three-phase drive WAP5 locomotives & 23 WAP7 locomotives.
Locomotives of ELS/GZB are hauling most of the prestigious Rajdhani/Shatabdi trains on electrified routes. Team of ELS/GZB feels proud in being nominated for offering locos for hauling trains at 150 KMPH. Electric Loco Shed, Ghaziabad is proud of holding the maximum number of Electric Coaching locos on Indian Railway, which is indicative of the faith Railway Administration has in the team of ELS/GZB. It has been a constant endeavor of the entire team, to meet expectation of the Railway Administration as well as the Public in terms of reliability, safety and availability of electric locomotive.
Recently 23 three-phase drive WAP7 locos have been received at ELS/GZB, and they are being maintained with out any additional input of manpower & infrastructure resources. The shed has successfully adopted the changes in technology of Electric locomotives from WAM4 locomotives to the present day State-of-the-Art Technology of three-phase drive of WAP5 & WAP7 locomotives. It has been possible due to team spirit and willingness of the entire team to adopt and update itself with new technology.
Initially, 10 WAP5 locomotives were imported from ABB/Switzerland and were put in service trials in 1997. These locomotives were imported along with technology transfer. The average kilometer earning of these locomotives comes upto 2. 85-lakh km per year per loco, which is 1? times compared to other electric mail/express locomotives. These WAP5 & WAP7 locomotives are hauling the most prestigious trains of Indian Railway like Rajdhanis & Shatabdis. SALIENT FEATURES 1. ESTABLISHED 1976 2. PRESENT LOCO HOLDING 138 . TYPE OF LOCOS WAP1 WAP4 WAP5 WAP7 WAG5 WAM4 4. TOTAL WORK FORCE OFFICERS 05 SUPERVISORS74 SKILLED DIRECT 588 SKILLED ANCILLARY78 UNSKILLED DIRECT 150 UNSKILLED ANCILLARY 24 5.
INITIAL COST 1. 5 (Rs. IN CRORES ) 6. AREA8910 (IN SQ. MTRS. ) ELECTRIC LOCOMOTIVE: An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or an on-board energy storage device (such as a chemical battery or fuel cell). Electrically propelled locomotives with on-board fuelled prime movers, such as diesel engines or gas turbines, are classed as diesel-electric or gas turbine electric locomotives because the electric generator/motor combination only serves as a power transmission system.
Electricity is used to eliminate smoke and take advantage of the high efficiency of electric motors; however, the cost of railway electrification means that usually only heavily used lines can be electrified. Electric locomotives benefit from the high efficiency of electric motors, often above 90%. Additional efficiency can be gained from regenerative braking, which allows kinetic energy to be recovered during braking to put some power back on the line. Newer electric locomotives use AC motor-inverter drive systems that provide for regenerative braking.
HISTORY: The first known electric locomotive was built in 1837 by chemist Robert Davidson of Aberdeen. It was powered by galvanic cells (‘batteries’). Davidson later built a larger locomotive named Galvani which was exhibited at the Royal Scottish Society of Arts Exhibition in 1841. The 7-ton vehicle had two direct-drive reluctance motors, with fixed electro-magnets acting on iron bars attached to a wooden cylinder mounted on each axle, and simple commutators. It hauled a load of 6 tons at 4 miles per hour for a distance of 1? miles.
The machine was tested on the Edinburgh and Glasgo Railway in September of the following year but the limited electric power available from batteries prevented its general use. It was destroyed by railway workers, who saw it as a threat to their security of employment. The first electric passenger train was presented by Werner von Siemens at Berlin in 1879. The locomotive was driven by a 2. 2 kW series wound motor and the train, consisting of the locomotive and three cars, reached a maximum speed of 13 km/h. During four months, the train carried 90,000 passengers on a 300 metre long circular track.
The electricity (150 V DC) was supplied through a third, insulated rail situated between the tracks. A contact roller was used to collect the electricity from the third rail. The world’s first electric tram line opened in Lichterfelde near Berlin, Germany, in 1881. It was built by Werner von Siemens (Gross-Lichterfelde Tramway and Berlin Stra? enbahn). In Britain, Volk’s electric railway was opened in 1883 in Brighton (see Volk’s Electric Railway). Also in 1883, Modling and Hinterbruhl Tram was opened near Vienna in Austria.
It was the first tram and railway in the world in regular service that was run with electricity served by an overhead line. Five years later, in the US electric trolleys were pioneered in 1888 on the Richmond Union Passenger Railway, using equipment designed by Frank J. Sprague. Much of the early development of electric locomotion was driven by the increasing use of tunnels, particularly in urban areas. Smoke from steam locomotives was noxious and municipalities were increasingly inclined to prohibit their use within their limits.
Thus the first successful working, the City and South London Railway underground line in the UK, was prompted by a clause in its enabling act prohibiting use of steam power. This line opened in 1890, using electric locomotives built by Mather and Platt. Electricity quickly became the power supply of choice for subways, abetted by the Sprague’s invention of multiple-unit train control in 1897. Surface and elevated rapid transit systems generally used steam until forced to convert by ordinance. ELECTRIC LOCOMOTIVE TYPES: An electric locomotive can be supplied with power from Rechargeable energy storage systems, as battery or ultracapacitor-powered mining locomotives. * A stationary source, such as a third rail or overhead wire. This is in marked contrast to a diesel-electric locomotive, which combines an onboard diesel engine with an electrical power transmission or store (battery, ultracapacitor) system. The distinguishing design features of electric locomotives are: * The type of electrical power used, either alternating current or direct current. * The method for store (batteries, ultracapacitors) or collecting (transmission) electrical power. The means used to mechanically couple the traction motors to the driving wheels (drivers). Direct and alternating current The most fundamental difference lies in the choice of direct (DC) or alternating current (AC). The earliest systems used direct current as, initially, alternating current was not well understood and insulation material for high voltage lines was not available. Direct current locomotives typically run at relatively low voltage (600 to 3,000 volts); the equipment is therefore relatively massive because the currents involved are large in order to transmit sufficient power.
Power must be supplied at frequent intervals as the high currents result in large transmission system losses. As alternating current motors were developed, they became the predominant type, particularly on longer routes. High voltages (tens of thousands of volts) are used because this allows the use of low currents; transmission losses are proportional to the square of the current (e. g. twice the current means four times the loss). Thus, high power can be conducted over long distances on lighter and cheaper wires.
Transformers in the locomotives transform this power to a low voltage and high current for the motors. A similar high voltage, low current system could not be employed with direct current locomotives because there is no easy way to do the voltage/current transformation for DC so efficiently as achieved by AC transformers. Italian freight locomotive E554 working with three-phase current. Note the two current collectors with separate heads for each phase. Picture taken in Liguria 1974. AC traction still occasionally uses dual overhead wires instead of single phase lines.
The resulting three-phase current drives induction motors, which do not have sensitive commutators and permit easy realisation of a regenerative brake. Speed is controlled by changing the number of pole pairs in the stator circuit, with acceleration controlled by switching additional resistors in, or out, of the rotor circuit. The two-phase lines are heavy and complicated near switches, where the phases have to cross each other. The system was widely used in the northern part of Italy until 1976 and is still in use on some Swiss rack railways.
The simple feasibility of a fail safe electric brake is an advantage of the system, while the speed control and the two-phase lines are problematic. In India, both AC and DC type of electrified train systems operate today. A 1,500 V DC-based train system is only operating in the Mumbai area. It is being converted to the 25 kV AC system. The rest of the India, where routes are electrified fully, operate under the 25 kV AC overhead wire. As of 2006, Indian railways haul 80% of freight and 85% of passenger traffic with electric locomotives.
ELECTRIC LOCOMOTIVE PARTS: PANTOGRAPH: A pantograph is a device that collects electric current from overhead lines for electric trains or trams. The most common type of pantograph today is the so called half-pantograph (sometimes ‘Z’-shaped), which has evolved to provide a more compact and responsive single-arm design at high speeds as trains get faster. The half-pantograph can be seen in use on everything from very fast trains to low-speed urban tram systems. The design operates with equal efficiency in either direction of motion. Fig. Pantograph The electric transmission system for modern electric rail systems consists of an upper weight carrying wire (known as a catenary) from which is suspended a contact wire. The pantograph is spring loaded and pushes a contact shoe up against the contact wire to draw the electricity needed to run the train. The steel rails on the tracks act as the electrical return. As the train moves, the contact shoe slides along the wire and can set up acoustical standing waves in the wires which break the contact and degrade current collection.
This means that on some systems adjacent pantographs are not permitted. Pantographs are the successor technology to trolley poles, which were widely used on early streetcar systems and still are used by trolleybuses, whose freedom of movement and need for a two-wire circuit makes pantographs impractical. Pantographs with overhead wires are now the dominant form of current collection for modern electric trains because, although more expensive and fragile than a third-rail system, they allow the use of higher voltages.
Pantographs are typically operated by compressed air from the vehicle’s braking system, either to raise the unit and hold it against the conductor or, when springs are used to effect the extension, to lower it. As a precaution against loss of pressure in the second case, the arm is held in the down position by a catch. For high-voltage systems, the same air supply is used to “blow out” the electric arc when roof-mounted circuit breakers are used. BRAKES: A moving train contains energy, known as kinetic energy, which needs to be removed from the train in order to cause it to stop.
The simplest way of doing this is to convert the energy into heat. The conversion is usually done by applying a contact material to the rotating wheels or to discs attached to the axles. The material creates friction and converts the kinetic energy into heat. The wheels slow down and eventually the train stops. The material used for braking is normally in the form of a block or pad. Types of Brakes Used: i) Air Brakes ii) Regenerative Brakes AIR BRAKES: The vast majority of the world’s trains are equipped with braking systems which use compressed air as the force to push blocks on to wheels or pads on to discs.
These systems are known as “air brakes” or “pneumatic brakes”. The compressed air is transmitted along the train through a “brake pipe”. Changing the level of air pressure in the pipe causes a change in the state of the brake on each vehicle. It can apply the brake, release it or hold it “on” after a partial application. Principle Parts: i) Compressor ii) Main Reservoir iii) Driver’s Brake Valve iv) Feed Valve v) Equalizing Reservoir vi) Brake Pipe vii) Angle Cocks viii) Coupled Hoses ix) Brake Cylinder x) Auxiliary reservoir xi) Brake Block Brake Positions: i) Application Position ii) Release Position ii) Lap Position i) Application Position: This diagram shows the condition of the brake cylinder, triple valve and auxiliary reservoir in the brake application position. The driver has placed the brake valve in the “Application” position. This causes air pressure in the brake pipe to escape. The loss of pressure is detected by the slide valve in the triple valve. Because the pressure on one side (the brake pipe side) of the valve has fallen, the auxiliary reservoir pressure on the other side has pushed the valve (towards the right) so that the feed groove over the valve is closed.
Fig. – Brake in application Pos. The driver has placed the brake valve in the “Application” position. This causes air pressure in the brake pipe to escape. The loss of pressure is detected by the slide valve in the triple valve. Because the pressure on one side (the brake pipe side) of the valve has fallen, the auxiliary reservoir pressure on the other side has pushed the valve (towards the right) so that the feed groove over the valve is closed. The connection between the brake cylinder and the exhaust underneath the slide valve has also been closed.
At the same time a connection between the auxiliary reservoir and the brake cylinder has been opened. Auxiliary reservoir air now feeds through into the brake cylinder. The air pressure forces the piston to move against the spring pressure and causes the brake blocks to be applied to the wheels. Air will continue to pass from the auxiliary reservoir to the brake cylinder until the pressure in both is equal. This is the maximum pressure the brake cylinder will obtain and is equivalent to a full application. To get a full application with a reasonable volume of air, the volume of the brake cylinder is usually about 40% of that of the uxiliary reservoir. ii) Release Position: This diagram shows the condition of the brake cylinder, triple valve and auxiliary reservoir in the brake release position. Fig. – Brake in Release pos. The feed groove allows brake pipe air pressure to enter the auxiliary reservoir and it will recharge it until its pressure is the same as that in the brake pipe. At the same time, the connection at the bottom of the slide valve will allow any air pressure in the brake cylinder to escape through the exhaust port to atmosphere.
As the air escapes, the spring in the cylinder will push the piston back and cause the brake blocks to be removed from contact with the wheels. The train brakes are now released and the auxiliary reservoirs are being replenished ready for another brake application. iii) Lap Position: The purpose of the “Lap” position is to allow the brake rate to be held constant after a partial application has been made. Fig. – Brake in Lap Pos. When the driver places the brake valve in the “Lap” position while air is escaping from the brake pipe, the escape is suspended.
The brake pipe pressure stops falling. In each triple valve, the suspension of this loss of brake pipe pressure is detected by the slide valve because the auxiliary pressure on the opposite side continues to fall while the brake pipe pressure stops falling. The slide valve therefore moves towards the auxiliary reservoir until the connection to the brake cylinder is closed off. The slide valve is now half-way between its application and release positions and the air pressures are now is a state of balance between the auxiliary reservoir and the brake pipe.
The brake cylinder is held constant while the port connection in the triple valve remains closed. The brake is “lapped”. Lap does not work after a release has been initiated. Once the brake valve has been placed in the “Release” position, the slide valves will all be moved to enable the recharge of the auxiliary reservoirs. Another application should not be made until sufficient time has been allowed for this recharge. The length of time will depend on the amount of air used for the previous application and the length of the train
REGENERATIVE BRAKING: Regenerative braking is the use of the electric traction motors of a railroad vehicle as generators & power is returned to the supply line when slowing the vehicle. Regenerative braking lowers the wear of friction-based braking components, and additionally regeneration can also lower energy consumption. During braking, the traction motor connections are altered to turn them into electrical generators. The motor fields are connected across the main traction generator (MG) and the motor armatures are connected across the load.
The MG now excites the motor fields. The rolling locomotive or multiple unit wheels turn the motor armatures, and the motors act as generators, either sending the generated current back into the supply. For a given direction of travel, current flow through the motor armatures during braking will be opposite to that during motoring. Therefore, the motor exerts torque in a direction that is opposite from the rolling direction. Braking effort is proportional to the product of the magnetic strength of the field windings, times that of the armature windings.
TRACTION MOTOR: The AC electric motor driving a train or locomotive is a simple machine consisting of a case containing a fixed electrical part, the stator (called the stator because it is static and comprising what is called the field coils) and a moving electrical part, the rotor (because it rotates) or armature as it is often called. As the rotor turns, it turns a pinion which drives a gearwheel. Fig. – AC Traction Motor The gearwheel is shrunk onto the axle and thus drives the wheels as shown in the diagram above.
The motion of the motor is created by the interaction of the magnetism caused by the currents flowing the stator and the rotor. This interaction causes the rotor to turn and provide the drive. The stator and the rotor of the AC motor are connected electrically. The connection consists of fixed, carbon brushes which are spring loaded so that they remain in contact with an extension of the armature called the commutator. In this way, the field coils (the stator) are kept in the circuit with the rotor (the armature and commutator). Nose Suspended Traction Motor:
The following diagram shows the layout of the traditional AC motor mounted in a bogie as a “nose suspended motor” . Fig. – Nose Suspended Traction Motor In electric trains or locomotives, the AC motor is mounted in the bogie frame supported partially by the axle which it drives and partially by the bogie frame. The motor case is provided with a “nose” which rested on a bracket fixed to the transom of the bogie. It is called a “nose suspended motor” (see diagram above). Its main disadvantage is that part of the weight rests on the axle and is therefore unsprung. This leads to greater wear on bogie and track.
Nowadays, designers try to ensure all the motor weight is sprung by ensuring it is carried entirely by the bogie frame – a frame mounted motor. WHEELS: Cast steel wheels are manufactured by a controlled pressure pouring process. In this process, the raw material used is pedigree scrap (old used wheelsets, axles etc, rejected as unfit for use by the Railways). The scrap steel is melted in Ultra High Frequency Electric Arc furnace. The correct chemistry of molten metal steel is established through a Spectrometer. The wheels are eventually get cast in the graphite moulds, which are pre-heated and sprayed.
After allowing for a pre-determined setting time the mould is spilt and the risers are automatically separated from the cast wheel. The wheel is then subjected to various heat treatments. The wheel undergoes the process of cleaning, checking, peening and various stages of inspections. The wheel produced by this process requires no machining except the precession boring of heats central hole (hub) where the axle has to be fitted. Fig. –Railway Wheels Railway wheels sit on the rails without guidance except for the shape of the tire in relation to the rail head.
Contrary to popular belief, the flanges should not touch the rails. Flanges are only a last resort to prevent the wheels becoming derailed – a safety feature. Fig. – The shape and location of wheels and rails on straight track. The wheel tire is coned and the rail head slightly curved as shown in the following diagram. The degree of coning is set by the railway company and it varies from place to place. PRIME MOVER: A prime mover is an engine that converts fuel to useful work . In locomotives, the prime mover is thus the source of power for its propulsion.
The term is generally used when discussing any locomotive powered by an internal combustion engine. The term is also applied to engine-generator sets, where the engine is termed the prime mover, as distinct from the generator. In a diesel-mechanical locomotive, prime mover refers to the diesel engine that is mechanically coupled to the driving wheels (drivers). In a diesel-electric locomotive, prime mover refers to the diesel engine that rotates the main generator responsible for producing electricity to power the traction motors that are geared to the drivers. The prime mover can also be a gas turbine instead of a diesel engine.
In either case, the generator, traction motors and interconnecting apparatus are considered to be the power transmission system and not part of the prime mover. An electric or battery-electric locomotive has no on-board prime mover, instead relying on an external power station. The term power unit is also sometimes used in application to diesel locomotives, with a similar meaning. Where the engine and generator set of a diesel-electric locomotive are removable as a unit, it is usual to term the coupled pair of them as “the power unit” but “prime mover” is only applied to the diesel engine.
MOTOR BLOWERS: Traction motors on electric locomotives get very hot and, to keep their temperature at a reasonable level for long periods of hard work, they are usually fitted with electric fans called motor blowers. On a modern locomotive, they are powered by an auxiliary 3-phase AC supply of around 400 volts supplied by an auxiliary inverter. BATTERY: All trains are provided with a battery to provide start up current and for supplying essential circuits, such as emergency lighting, when the line supply fails. The battery is usually connected across the DC control supply circuit MAIN TRANSFORMER:
A set of windings with a magnetic core used to step down or step up a voltage from one level to another. The voltage differences are determined by the proportion of windings on the input side compared with the proportion on the output side. An essential requirement for locomotives and trains using AC power, where the line voltage has to be stepped down before use on the train. AXLE BRUSH: The means by which the power supply circuit is completed with the substation once power has been drawn on the locomotive. Current collected from the overhead line or third rail is returned via the axle brush and one of the running rails.
CIRCUIT BREAKER: An electric train is almost always provided with some sort of circuit breaker to isolate the power supply when there is a fault, or for maintenance. On AC systems they are usually on the roof near the pantograph. There are two types – the air blast circuit breaker and the vacuum circuit breaker or VCB. The air or vacuum part is used to extinguish the arc which occurs as the two tips of the circuit breaker are opened. The VCB is popular in the UK and the air blast circuit breaker is more often seen on the continent of Europe. TYPES OF LOCO HOLDINGS IN LOCOSHED GHAZIABAD: . WAP1: WAP1 was built by CLW to RDSO specifications. First in the dedicated electric passenger loco series. Production began in 1980 and the locos were at first used solely for the Howrah-Delhi Rajdhani. A single WAP-1 was all that was needed to haul the 18-coach Rajdhani at a max. speed of 120 km/h. and an average speed of around 82km/h. Continuous power 3760hp; starting TE 22. 2t, continuous TE 13. 8t. Loco weight is 112. 8t Many remaining WAP-1’s are being converted to WAP-4’s by a complete retrofit including new traction motors, new transformers, etc.
These upgrades do not result in the ‘R’ suffix in the road number that is typical for rebuilt locos. Ghaziabad shed locos are currently [1/05] the only ones not scheduled for such upgrades and are expected to remain as ‘pure’ WAP-1 units. The WAP-1E has only air brakes. Technical Specifications: Manufacturers| Chittaranjan locomotive works| Traction Motors| Alstom/CLW – TAO 659 (575kW (770hp), 750V, 1095 rpm) Axle-hung, nose-suspended, force-ventilated. | Gear Ratio| 58:21| Transformer| BHEL type HETT-3900, 3900 kVA. 32 taps. | Axle load| 18. 8 t|
Bogies| Co-Co Flexicoil (cast steel bogies); primary and secondary wheel springs with bolsters. | Pantographs| Two Stone India (Calcutta) AM-12. | Current Ratings| 1000 A for 10 min, 900 A continuous| 2. WAP4 : WAP-4 is one of the most important electric locomotives used in India. It is a very powerful class capable of hauling 26 coaches at a speed of 140 km/h. It is also among the most widely used locomotives. The locomotive was developed, after a previous class WAP-1 was found inadequate to haul the longer, heavier express trains that were becoming the mainstay of the Indian Railways network.
It was introduced in 1994, with a similar bodyshell to the WAP-1 class, but with Hitachi traction motors developing 5000 hp (5350 hp starting). Electricals are traditional DC loco type tap changers, driving 6 traction motors arranged in Co-Co fashion. This locomotive has proved to be highly successful, with over 450 units in service and more being produced. Newer examples have been fitted with Microprocessor Controlled diagnostics, Static Converter units (instead of arnos) and roof mounted Dynamic (Rheostatic) Brakes. Technical Specifications:-
Manufacturers| Chittaranjan locomotive works| Traction Motors| Hitachi HS15250 (630 kW, 750 V (New P4 [**67* onwards] are 900 volts), 900 A, 895 rpm. Weight 3500 kg). Axle-hung, nose-suspended, force ventilated, taper roller bearings| Gear Ratio| 23:58 (One loco, #22559, is said to have a 23:59 ratio. )| Transformer| 5400 kVA, 32 taps| Axle load| 18. 8 t| Bogies| Co-Co Flexicoil Mark 1 cast bogies; primary and secondary wheel springs with bolsters| Pantographs| Two Stone India (Calcutta) AM-12. | Current Ratings| 1000 A for 10 min, 900 A continuous| . WAP5: WAP 5 is the name of a class of electric locomotive used by Indian Railways. The first 10 locos were imported from ABB in Switzerland in 1995. Chittaranjan Locomotive Works (CLW) started production in 2000. It was designed to haul 18 coach passenger trains at 160 km/h. It is the first 3-phase loco in India. Other notable features of this loco are the provision of taps from the main loco transformers for hotel load, pantry loads, flexible gear coupling, wheel-mounted disc brakes, and a potential for speed enhancement to 200 km/h. 8 tonnes weight. Braking systems include regenerative braking (160kN), loco disc brakes, automatic train air brakes, and a charged spring parking brake. MU operation possible with a maximum of two locos. At trials, a WAP-5 has been tested upto 184km/h The WAP-5 series of locomotives haul the premium trains on Indian Railways like the Mumbai Rajdhani Express, Bhopal Shatabdi Express, Lucknow Shatabdi Express, Prayagraj Express, etc. Technical Specifications:- Manufacturers| ABB / Chittaranjan Locomotive Works| Capacity| 4 MW (4000 kW, 5450 hp)|
Traction Motors| ABB’s 6FXA 7059 3-phase squirrel cage induction motors (1150kW, 2180V, 370/450A, *1583/3147 rpm) Weight 2050 kg. Forced-air ventilation, fully suspended. Torque 6930/10000 Nm. 96% *efficiency. | Gear Ratio| 67:35:17. (3-stage gears)| Transformer| ABB’s LOT-7500. 7475kVA primary, 4x1450kVA secondary. | Axle load| 19. 5 t| Bogies| Bo-Bo Henschel Flexifloat; bogie centre distance 10200 mm; bogie wheel base 2800 mm Unsprung mass per axle: 2. 69t| Pantographs| Two Stone India (Calcutta) AM-92, Schunk for the imported locomotives. Wheel diameter| 1092 mm new, 1016 mm worn| 4. WAP7: WAP 7 is a high speed locomotive indigenously developed by Chittaranjan Locomotive Works. It is capable of hauling trains at speeds ranging between 140 and 160 km per hour and is now largely used by Northern Railways and South Central Railways(SCR). The WAP-7 is actually a modified version of the WAG 9 freight locomotive with modified gear ratios and is set to replace the fleet of WAP 4s. With a maximum speed rating of 140 km/h, the WAP-7 boasts of the most phenomenal acceleration figures while hauling mail/express trains.
The WAP7 can also haul loads of 24-26 passenger coaches (1430-1550 t) at 110+ km/h per hour. It is also known to haul 16 heavyweight Air Conditioned coaches (1120t) in 1:40 inclines single-handedly. At a trial conducted by Indian Railways, it clocked a speed of 177 km/h. It is the most successful passenger locomotive in the Indian Railways portfolio after the WAP4. It is used to haul premium trains like Rajdhani and Shatabdi express apart from other regular mail/express trains. It also regularly hauls other trains like the New Delhi-Chennai, New Delhi-Bangalore, New Delhi-Sealdah and the New Delhi – Mumbai Rajdhani Expresses.
The most unique feature of this locomotive is that it eliminates the need to have separate DG sets for air-conditioning in long distance trains hence saving huge on maintenance and running costs. A 24-coach (1430t) passenger rake can be accelerated to 110 km/h in 240 seconds (over 4. 7 km) by a WAP-7; to 120 km/h in 304 sec. (6. 7 km); and to 130 km/h in 394 sec. (9. 9 km). Technical Specifications:- Manufacturers| CLW| Traction Motors| 6FRA 6068 3-phase squirrel-cage induction motors (850 kW, 2180V, 1283/2484 rpm, *270/310A. Weight| Gear Ratio| 72:20|
Axle load| 20. 5t| Wheel diameter| 1092mm new, 1016mm worn| Wheel base| 15700mm| Bogies| Co-Co, Fabricated Flexicoil Mark IV bogies; bogie wheel base 1850mm + 1850mm| Unsprung mass | 3. 984t| 5. WAG5: WAG5 was introduced in 1984. Starting TE 382kN (33500kgf); continuous TE 202kN (20600kgf). Adhesion 29%. A very successful class, and probably the one with the most numbers produced. There are many variants of these, starting with the plain WAG-5. WAG-5A locos have Alsthom motors. Later versions were WAG-5H and variants with Hitachi motors.
Although a great improvement over earlier locomotive classes, the WAG-5 models do have limitations, one of which is the inability to start and haul large loads (4700t — 58 BOXN wagons) on gradients steeper than 1:200 or so. WAG-5 locos can be used as multiple units in configurations of 2, 3, 4, or more locos. With the large influx of WAG-7 and WAG-9 locos in recent years, many WAG-5 locos are now also being put to use hauling local passenger trains. Some such as the WAG-5E loco #23989 ‘Krishnaveni’ (of Vijayawada [1/04]) have also been modified for this purpose in their interior equipment as well as some of the exterior aspects.
For some reason, the BHEL-built WAG-5HA / 5HB locos are never seen used with passenger trains. All of the WAG-5HB units are at Jhansi near BHEL’s own installations so that BHEL can handle their maintenance. Technical specifications Manufacturers| Chittaranjan locomotive works| Traction Motors| Alstom TAO 659 (575kW, 750V, 1070 rpm) or TAO 656; or Hitachi HS 15250A (See description under WAP-4. ) Axle-hung, nose-suspended. Six motors. | Gear Ratio| 62:16 or 62:15 with Alstom motors, some 64:18 (Hitachi motors), many now 58:21 for mixed use. | Transformer| BHEL, type HETT-3900. 3900kVA, 22. kV, 182A. 32 taps. | Axle load| 20t| Bogies| Co-Co cast bogies (Alco asymmetric trimount — shared with WDM-2, WAM-4). | Pantographs| Two Stone India (Calcutta) AM-12. | Current Ratings| 1100A/10min, 750A continuous. | 6. WAM4: WAM-4 is the name of a type of electric locomotive used in India. It is a very successful locomotive in Indian Railways’ fleet. The first one was indigenously designed and built by CLW in 1970-71. They were produced until about 1997. They use the same power bogies as the successful WDM-2 class. These locos feature rheostatic braking, and MU capability.
Being designed specially for mixed traffic these locos has rendered excellent service. Technical Specifications:- Manufacturers| CLW| Traction Motors| Alstom TAO 659 A1 (575kW, 750V). Six motors, axle-hung, nose-suspended, force-ventilated. | Gear Ratio| 15:62 originally (and still for WAM-4 2S3P), now many variations, 21:58 being common for WAM-4 6P locos. | Transformer| Heil BOT 3460 A, 22. 5kV / 3460kVA. | Rectifiers| Two silicon rectifier cells, 1270V / 1000A each cubicle. | Pantographs| Two Faiveley AM-12. | Axle load| 18. 8t| Hauling capacity| 2010t| Current Ratings| (WAM-4 6P) 1100A/10min, 750A continuous|
