03-01-2013, 10:24 AM
BHARAT SANCHAR NIGAM LIMITED AT BHARAT NAGAR CHOWK, LUDHIANA
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INTRODUCTION
NORTHERN RAILWAY, DIESEL SHED, LUDHIANA
Diesel Shed Ludhiana came into existence on 29.09.1977. Initially, the shed was designed to
home 60 WDM2 locos. Later, it was expanded to home 100 WDM2 locos in the year 1987-
88. Further the total holding of shed was increased to 150 locos in the year 1993-94. Present
loco holding of Diesel Shed, Ludhiana is 170 having different types of broad gauge locomotive i.e. WDM2, WDM3A & WDG3A. At present Ludhiana Diesel Shed is the biggest shed on the Northern Railway and the 3rd largest in Indian Railways. The total kilometers earning is approximately 22 Lakh Kilometers per month and the shed is running a mail link of 96 locos consisting of various prestigious Mail/Express trains. Diesel Shed, Ludhiana is also having a Diesel Training School and Hostel attached to it. The Training School consists of 5 classrooms and various working models of mechanical and electrical sub assemblies of WDM2 locos. The staying capacity in the hostel is 72 and is having 38 double-bedded rooms. This training School is being mainly utilized for training of running staff for Diesel conversion and refresher courses of FZR & UMB division. In addition to this, this is also being utilized for imparting training to the maintenance staff of the shed. It is also equipped with the recreation facilities &gymnasium with high-tech exercise machines, indoor games etc. Diesel Shed, LDH is ISO0-14001 Certified Establishment, which is headed by under the dynamic control of Sr. Div. Mechanical Engineer (Diesel), under whom the officers DME-I, DME-II, ADME/H, ADME/R/Mech., ADME/R/Elect, ACMT & SMM/Stores are working.
OVERVIEW
Early internal combustion engine-powered locomotives used gasoline as their fuel. Soon after
Dr. Rudo Diesel patented his first compression ignition engine in 1892, its application for railway propulsion was considered. Progress was slow, however, due to the poor power-to-weight ratio of the early engines, as well as the difficulty inherent in mechanically applying power to multiple driving wheels on swivelling trucks (bogies).Steady improvements in the Diesel engine's design (many developed by
Sulzer Ltd. of Switzerland
, with whom Dr. Diesel was associated for a time) gradually reduced its physical size and improved its power-to-weight ratio to a point where one could be mounted in a locomotive. Once the concept of Diesel-electric drive was accepted the pace of development quickened. By the mid 20th century the Diesel locomotive had become the dominant type of locomotive in much of the world, offering greater flexibility and performance than the steam locomotive, as well as substantially lower operating and maintenance costs. Currently, almost all Diesel locomotives are Diesel-electric.
Engine Description
Diesel Engine, Main Alternator ,Auxiliary Alternator, Motor Blower, Air Intakes, Rectifiers inverters, Electric Controls, Control Stands, Batteries, Cab, Traction Motor .Pinion Gear, Fuel Tank , Air compressor, Drive Shaft, Gear Box, Radiator and Radiator Fan, Turbo charging, Sand Box, Truck Frame, Wheel, Brakes, Mechanical Transmission, Fluid Coupling
Final Drive, Hydraulic Transmission, Wheel Slip
Traction Motor Applications
Traditionally, these were series-wound brushed DC motors, usually running on approximately 600 volts. The availability of high-powered semiconductors (such as thyristors and the IGBT) has now made practical the use of much simpler, higher-reliability AC induction motors known as asynchronous traction motors. It is now standard practice to provide one traction motor driving each axle through a gear drive.
Usually, the traction motor is three-point suspended between the bogie frame and the driven axle; this is referred to as a "nose-suspended traction motor". The problem with such an arrangement is that a portion of the motor's weight is unsprung, increasing unwanted forces on the track. The rotating shaft of the motor was also the axle for the wheels.
The DC motor was the mainstay of electric traction drives on both electric and diesel-electric locomotives, street-cars/trams and diesel electric drilling rigs for many years. It consists of two parts, a rotating armature and fixed field windings surrounding the rotating armature mounted around a shaft. The fixed field windings consist of tightly wound coils of wire fitted inside the motor case. The armature is another set of coils wound round a central shaft and is connected to the field windings through "brushes" which are spring-loaded contacts pressing against an extension of the armature called the commutator. The commutator collects all the terminations of the armature coils and distributes them in a circular pattern to allow the correct sequence of current flow. When the armature and the field windings are connected in series, the whole motor is referred to as "series-wound". A series-wound DC motor has a low resistance field and armature circuit. Because of this, when voltage is applied to it, the current is high due to Ohms Law. The advantage of high current is that the magnetic fields inside the motor are strong, producing high torque (turning force), so it is ideal for starting a train. The disadvantage is that the current flowing into the motor has to be limited, otherwise the supply could be overloaded or the motor and its cabling could be damaged. At best, the torque would exceed the adhesion and the driving wheels would slip. Traditionally, resistors were used to limit the initial current.