15 - Indian Railways Institute of Mechanical and Electrical Engineering

15. Locomotive Testing And Painting
Locomotive Test
General Motors adheres to following concept/philosophy:
All individual assemblies and components are tested during the
locomotive assembly either at the GM works or at the supplier end.
All electronic and air brake equipment are to be left unplugged during
15.2 Testing should verify/ audit integration of all locomotive system and sub-system.
A very elaborate test procedure for the complete locomotive is followed by EMD before
the locomotive is put on line. The test procedure is based on the relevant Engineering
Test Instructions, defects found on previous units and reports from the service
department. In case of GT46MAC, which would be a prototype even as it is electrically
similar to SD70MAC, the procedure for the first locomotive is a more exhaustive and
stringent test protocol. After completion of testing, the test records are scrutinised. As
test checks are completed or at the end of the shift, they are to be initialled by the test
personnel opposite to the test numbers.
After the preliminary inspection, Hi Pot Test for power & control circuits including
Dynamic brake is done to ensure that no damage has been done during production
assembly. It is followed by continuity check on various sub-system and installation of
EM2000 modules. All the connections to other electronic system are completed and
power-up & self-tests done. During testing the following safety procedure are taken into
The second stage of testing starts with pre-lube of engine. The engine is started
and all mechanical and electrical checks including Siemen’s Commissioning checks are
completed. A pre-load test is done to confirm that other systems are ready for load test,
e.g., Inertial blower and also customer specific feature, if any. During the load test, the
locomotive power output is dissipated in the dynamic grids to confirm the integrity of the
cabling of Dynamic brake system. The locomotives not having self load Test feature,
are connected to external grids. During the Load Test, measurement of cab noise and
vibrations at few selected locations are also done.
Finally, in the last stage, the locomotive is prepared for Track Test. Air brake
system is checked to ensure its integrity, besides any other specific feature which
remains to be checked. The track test is done on a test track of 1/2 miles length approx.
with maximum permissible speed of 35 kmph.(located in Diesel Division). it is done for
single unit as well as multiple unit. The functioning of speed indicator, ground relay and
pneumatic controls checked, besides push pull test for Dynamic brake Drag operation.
A pre-delivery inspection is carried out by down-loading all the fault/unusual
message encountered during testing of the loading and a final inspection carried out
before dispatching the locomotive.
 On microprocessor units whenever a module is installed or removed, power supply
to the computer is switched off. A wrist grounding strap is used.
 All the electronic system should be disconnected prior to megger and hi-pot testing.
 To check the continuity and test point voltage, only digital type meter should be used
 Under open circuit condition, the main generator should not be excited.
 The meter leads and jumpers should not touch the carbody ground from 15V
 Test points in 15 Volt supply should not be jumpered.
 Engine blow-out must be performed before starting the engine if the engine has
been down for eight hours or more.
Some preliminary tests like checking of hand brakes, wheels, air compressor,
engine oil, dust etc. are done before starting the actual testing. The testing consists of
the following well defined steps sequentially 
Hi Pot test
Trainline continuity
Lighting circuit
Blower/Fans operation
Power contactor operation
EM2000 module application and computer preliminary test
EM 2000 system integration
Dynamic brake signals
TM blower shutter
Engine run
Engine start
AG checks
Air compressor control, low air engine speed up & air system safety valve
TCC phase module temperature control
TCC power supplies, systems and operations test
Excitation test
Load test
Track test
Traction inverter cut-out
Multiple unit operation
Pre delivery test
Locomotive Painting:
The locomotive after complete testing is brought to specially designed painting
booth. The painting is done as per the following sequence:
Preparatory booth
The locomotive is washed, degreased and deburring of all external welded joints
completed. The appropriate areas e.g., consoles in the cab, TG fan, valves & pipes,
rubber side bearer etc. are masked.
Painting Booth
There are two painting booths where the following activity are done:
The external is coated with the epoxy primer.
The cab and long-hood exterior surfaces are given polyurethane paint coat.
The polyurethane masked stickers as per the painting style ( pertaining to rail
road name, road number and longitudinal strips) are affixed at the appropriate
locations. The masks are removed after the final painting.
The external surfaces including underframe & bogies are then given one coat of
polyurethane paint. Two hours drying time is given before applying another coat
of the same paint. The dry & wet gauges are used to measure the paint thickness
. Normally the paint thickness is of the order of 6 thou and its uniformity over the
surface is maintained by the experience of the painter.
EMD also have separate painting booth for small piece parts and underframe.
The underframe assembly after fabrication is given one coat of epoxy paint before &
after piping and cabling. Similarly assembled equipment rack is also given one coat of
epoxy paint.
Visits To Various Facilities
Visit To M/S Atchison Castings/Kansas -USA
Atchison Castings Corporation (ACC) was re-organized in 1991 with the purpose
of becoming a broad based foundry company. ACC products are iron and steel
castings ranging in size from 1 to 120, 000 lb. ACC customers are leaders in their own
field and include General Motors, Caterpillar, General Dynamics, Rockwell International,
Westinghouse, John Deere, General Electric, Morrison Knubsen, Bombardier, ABB etc.
The company was founded in Atchison, Kansas in 1872 to supply iron castings to
the Railroads. In 1956, the facility was acquired by Rockwell International. In 1991,
ACC acquired Rockwell’s Foundry in Atchison, Kansas and Machine Shop in St.
Joseph, MO.
All the castings are electronically analysed in the design development process
and create modifications using solidification software techniques, which optimise quality
and cost without adversely affecting functional performance. M/s Atchison Casting is
using their proprietary bonding agent. They have also very excellent sand recovery
All the casting ranges produced by ACC Castings are machined in fully finished
condition at St. Joe division (Atchison Castings Machine Shop) which is a separate
The casting of truck requires one piece thin walled, high integrity, frame
castings. With solidification and mould filling simulation on computer, the company is
able to achieve excellent quality. Bogie frame for HTSC truck have been developed as
U-section in place of traditional Box-section. This design eliminates use of cores. The
use of cores increase the cost of production and decrease the quality of castings. M/s
GM/EMD and M/s Atchison Castings have collaborated for development of this design.
It is learnt that for future supplies of cast steel HTSC bogie frames to DLW, M/s
Atchison Casting has entered into a TOT contract with M/s Simplex Engg. & Foundry
Visit To M/S Lord Corporation/ Erie/ PA - USA
Lord Corporation have facilities for designing, manufacturing and testing of metal
bonded rubber components as per customer requirements.
Main component supplied to EMD is metal bonded rubber spring used in
secondary suspension and metal bonded rubber bushes for various joints.
The design of metal bonded rubber spring is done on FEM package to optimise
the profile of rubber to avoid stress concentration.
Lord Corpn. have modern manufacturing facility for manufacture of metal
bonded rubber components. Transfer moulding process is followed for moulding the
rubber. For bonding between metal and rubber, they use special type of chemical
developed for this purpose.
M/s Lord corporation have extensive fatigue testing facilities. Company has set
up new testing shop which is equipped modern fatigue testing machines, vibration
shaker which are controlled by computer various data are recorded and analysed
further. since major percentage of their products are supplied to aircraft industry, so
they have installed three axis machines by which they can conduct all modes of testing
simultaneously. The locomotive components are required to be tested for one million
cycle at varying frequency.
Computer Aided Design By Unigraphics
EMD uses Unigraphics package which is a completely integrated software and is
used for drawing-drafting and modelling. The underframe, car body, cab, bogie frame
and other bogie components such as wheels, axles, axle box, traction motors,
suspension and brake rigging components are generated by solid modelling and
assembled together. The package is very useful for preparation of layouts and study of
infringement/clearances between different components of bogie. The package also
enables calculation of weights, moment of inertia and centre of gravity which are
required for vehicle dynamics studies. The models prepared by Unigraphics can be
transferred to ANSYS for finite element analysis. The package is supported by standard
library of components such as nuts, bolts, screws, etc.; the components most commonly
used can be generated and can also be included in the library.
Sizing of various cross section was done by keeping section modules of this
bogie frame same with a similar bogie frame with box section. Afterwards optimisation
of sections were carried out by FINITE ELEMENT ANALYSIS by applying load cases.
18.1 DLW should install Unigraphics system and ANSYS FEM package not only to
fully assimilate EMD technology but also develop expertise in design of new
locomotives of horse power ranging from 3000 to 5000 hp with EMD 12 cylinder and
20 cylinder engines.
18.2 DLW should follow EMD project management and design review process in
design and manufacture of locomotives and assemblies.
Track Gauge
Total Weight on Rails
Design Speed
Wheel Arrangement
(top of rail to top of cooling fan)
Overall Length Over Buffers
Fuel Capacity
Cooling Water Capacity
1676 mm
126 t
100 kmph
4,120 mm
21, 245 mm
6,000 L
1144 L
Performance Specification
Starting Tractive Effort
Braking effort capability
540 kN
270 kN
Fuel Injection
High Efficiency
Unit Fuel Injection
Traction Technology
No. of invertors
EM2000 Advanced Computer
32-bit microprocessor
Reduction in modules and components compared to Dash-2 series controls
Improved reliability and performance
Information can be downloaded to a laptop computer
Flexible and expendable to accommodate future system enhancements
Complete self-diagnostics
Archived unit history data,
HTSC Bogie
No wearing surfaces extends bogie overhaul intervals to 1.6 million km
Dual high adhesion and high speed
Available gear ratios for heavy haul and passenger operation
Cab Features
Air operated windshield wipers
Dual desk type control console - optional
Multi-resettable vigilance controls - optional
Air System
Direct drive air compressor
Brake System
Electronic Air Brake System
Reliability and Serviceability
90-day maintenance intervals
AC motors doubles traction motor life
No running maintenance required
No brushes, commutator, or rotor insulation
No flashovers
Bogie Inverter Control
High level of reliability with fewer parts
1.6 million kilometre overhaul with HTSC Bogie
6-year engine overhaul period
Safety Aspects
Increased Crashworthiness
Provision of Anti-climber