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INDIAN RAILWAYS MAINTENANCE MANUAL FOR DIESEL LOCOMOTIVES - PART 70

Document No:

Chapter –13 Technological Advancements

Version No: 1.0-d0

Date Issued: dd/mm/yyyy

Document Title: MANUAL MAINTENANCE FOR DIESEL LOCOMOTIVES

Revised 2013

Printed: 2015/03/08

Page 272 of 303

13.2

Technological Advancements

A brief write up is given below for understanding as to what

has happened in past and what is happening on the technological front at present in Motive Power
and Engine Development Directorate of RDSO.

13.2.1 Motive Power Directorate

13.2.1.1 Pertaining to Alco Family Locos

Description

Use

Since

Micro-processor based control system: Indian Railway had modernized the ALCO locomotive
by fitment of Microprocessor based excitation & control system. The introduction of
Microprocessor Control System in ALCO Locomotives fetched benefits like improved train
operation safety, improved locomotive operational characteristics, reduced maintenance,
flexibility to adopt new features.

2002-03

Plate type LO cooler: Plate type lube oil coolers are compact, have higher reliability and
efficiency as this design consists of alternate layers of thin and gasketted plates with hot and cold
fluids flowing between alternate plates offering greater heat transfer against shell and tube type
cooler. Guidelines for overhauling of Plate Type Lube Oil Cooler (PTLOC) being used on Indian
Railways DE (Alco type) locos was published vide RDSO Instruction bulletin. No.
MP.IB.ES.01.07.08.

2001-02

Mechanically Bonded Radiator: For improved reliability and longer life, mechanically bonded
radiators were planned for use on WDG2 & WDM3D locos. Mechanically bonded radiators use
seamless tubes, which are mechanically bonded with header, whereas in conventional radiators,
rolled tubes are soldered with the header, which is less reliable as compared to mechanical
expansion.

2002

Air Dryer: This removes moisture from compressed air resulting in improved life and reliability
of brake valves and other electro –pneumatic equipment.

1998

Alternator-mounted rectifier on alternator assembly type 10102EV: This project was taken
up with a view to improve the layout of locos as the rectifier occupies substantial space. WDM3D
locos are equipped with this design.

Improved insulation scheme for traction motors: With a view to improving the reliability of
the TM, traction motors with modified insulation scheme incorporating flexible wrapping tape
instead of Kapton mica wrapper, ceramic packing instead of Nomex and glass mica paper instead
of conventional glass mica with flakes and associated insulating materials introduced

Panel-mounted brakes for air brake locos: This improves reliability and facilitates
maintenance. Compact panel-mounted brakes for air brake locos with auxiliary dual brake panel:
Compact type panel mounting brakes with three plate’s design, which do not have external
jumper have been provided for superior maintainability and reliability. In addition, an auxiliary
panel for the dual brake system has also been provided to help maintainability.

Inconel exhaust valves: For improved reliability and longer life, exhaust valves of inconel
material and inlet valves of 21 -4N material with thick neck (30 Degrees seat angle) have been
introduced. The valve seat insert of Exhaust and Air makes interchangeable with 251 plus cyl.
head and conventional cyl. Head (ALCO). The interference for Inconel exhaust valve seat insert
in both the cases i.e conventional as well as 251 plus cylinder head assembly has been made
similar.

251+ cylinder heads: 251 + cylinder heads have thin wall section which enables better heat
transfer. Other design modifications include increased no of cores, use of frost plugs, etc,
resulting in better performance. Modification of M/s Cooper Corporation, Satara make 251 plus
cylinder head to improved its reliability was published vide MP.IB.EN.12.78.09.

1997

10.

Fluonlex cables for TMs: Fluonlex cables have higher flexibility & thermal rating as compared
to conventional EPR/CSP & Nylon-braided PCP cables in use on lead & brush gear-connector
application. A very high temperature rating, 150ºC or above and outstanding flexibility are the
advantages of these cables. Although successful on Hitachi motor, their application on diesel
locos has been limited due to economy considerations, as cables are very expensive. As these are
one time cables for traction motors, RDSO has recommended these cables Vide instruction
bulletin no MP.IB.EM.03.04.08 for all type of traction motors and the specification has been
upgraded.

11.

Rectifier with built-in blower (92 days sch.): For improved reliability and also reduced ducting
in the under frame, rectifiers with in-built blower have been fitted on WDG2 locos. Instruction

Draft

Document No:

Chapter –13 Technological Advancements

Version No: 1.0-d0

Date Issued: dd/mm/yyyy

Document Title: MANUAL MAINTENANCE FOR DIESEL LOCOMOTIVES

Revised 2013

Printed: 2015/03/08

Page 273 of 303

Description

Use

Since

bulletin NO. MP.IB.EM – 01.04.07 Dated 12-03-2007 was published by RDSO.

12.

Low maintenance battery (92 days sch.): DLW in association with EXIDE, India has developed
low maintenance battery which requires topping up after 92 days against 15 days for conventional
battery. Instruction bulletin no. MP. IB. EC.01.02.05 (rev.01), Dec. 2008 published by RDSO for
maintenance of batteries.

13.

E-beam cables:E-beam irradiation used in traction cables provides better insulation and
mechanical strength. These cables are able to withstand higher temperature which allows higher
current in the same cross section of conductor leading to considerable saving in copper and
weight. These cables are resistant to oil, last longer.
Advantages of E-beam cross-linked and Fluonlex cables are :
5.4.1 Reduced insulation thickness
5.4.2 Reduced space & weight requirement
5.4.3 Reduced heat content of the system
5.4.4 Higher temperature rating
5.4.5 Increased current rating
5.4.6 Increased cable life
5.4.7 Reduced conductor size and weight
5.4.8 Higher mechanical strength
5.4.9 Reduced bending radius & increased flexibility
5.4.10 Reduced space requirement
5.4.11 Improved cable layout
5.4.12 Higher resistance to oil
5.4.13 Flame retardant
5.4.14 Low smoke inversion
5.4.15 Increased flexibility

14.

Twin beam halogen headlight: Locos are being fitted with these headlights. Guidelines for
Procurement of halogen bulbs for twin beam headlight for D. E locos purchased from different
sources and Procedure for beam alignment of twin beam headlight was published vide Instruction
bulletin no. MP.IB.EC.01.08.06 date: 27-12-06

15.

Higher speed LO & water pumps: Low LO pressure to a great extent and water pressure to a
lesser extent have been an outstanding problem with ALCO locos. Failure to achieve the specified
minimum lube oil pressure on idle at elevated temperatures and on sudden notch down condition
has been leading to shut down of locos. It has been decided to change the gear ratio of the lube
and water pump gear train. To standardize, the overhauling periodicity of modified lube oil pump
(Herringbone type gear) fitted on Alco type diesel electric locos was published vide RDSO
Instruction Bulletin No. MP.IB.ES.08.66.09.

16.

Aesthetically & ergonomically designed driver’s cab with suitable amenities: After successful
implementation of the basic ergonomically designed driver’s cab with desk type master controller,
a critical review of the complaints, and more importantly the requirements of a modern driving
station, was done and a large number of features were conceptualized. Some of the important
features are improved cab structure with noise proofing, redesigned partition door, improved
locks, superior lights, superior gauges, amenities etc. Retro fitment of Driver’s Cab in ALCO
diesel locos with FRP Interiors was published vide RDSO Modification Sheet No. MP.MOD.LD-
02.35.10, (Rev 0.00), Dated 06.07.2010.

17.

Stiffer unit camshaft: Larger dia. cam lobes can withstand higher stresses thereby resulting in
higher camshaft life. In this design, one cam segment is meant for one cylinder and can be
attended separately. Each segment, therefore, can be removed and replaced easily by simply
removing the fuel pump support of that location. Valve timing adjustments of the adjacent
cylinders are not disturbed. In conventional design, whole camshaft assembly has to be
necessarily removed from the free end which takes too much time. Expected life of the camshaft
is more than conventional one. The concept of unit cam shaft, its advantages and the procedure of
fitment was published vide RDSO Instruction Bulletin No MP.IB-EN-04.21.00
Complete switch over to Stiffer Unit Camshaft (SUCS) on 3100 hp locos and use of modified
components in SUCS to increase the reliability was published vide RDSO Modification No.
MP.MOD.EN.08.36.09

18.

E-beam irradiated air brake kit gaskets, O-rings and diaphragms: New generation Rubber
Part Kits for Air Brake systems by E-beam radiation curing technique introduced

19.

AC motor for fuel pump & crankcase: In view of the inherent problems of bush holder &
commutator in DC motors, it has been decided to use AC fuel pump and Crankcase motor(s) with

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Document No:

Chapter –13 Technological Advancements

Version No: 1.0-d0

Date Issued: dd/mm/yyyy

Document Title: MANUAL MAINTENANCE FOR DIESEL LOCOMOTIVES

Revised 2013

Printed: 2015/03/08

Page 274 of 303

Description

Use

Since

built-in inverter. Use of hybrid bearings 6304-2RSL3/ HC5C3S0WT and radial shaft seal CR
20X45X7 HMS5V in AC Crank Case Exhauster motor to improve reliability and performance
was published vide RDSO Modification no. MP-MOD-EM-11-64-10 (Rev-00) May-10.
Implementation of auto reset feature & increase in starting torque in AC Fuel Pump Motor
developed by M/s Signotron (India) Pvt Ltd. Kolkata was published vide RDSO Modification no .
MP.MOD.EM.01.07.08 (Rev-00) Sept, 08

20.

Improved Fast and Flexible couplings:  The failures on fast couplings reported are due to
breakage of the coupling from the weld. The design has been modified to one piece integral
centrifugal  coupling and this design has been successful with the no. of failures reported going
down drastically. Other failure reported due to breakage of fast coupling bolts etc., also  have
been tackled. The failures reported on flexible couplings are due to deformation/degradation of
the rubber elements. The design has been modified to Nitrile rubber.

21.

Improved abrasion-resistant flexible hoses with crimped end fittings: For improved
performance of flexible hoses, use of flexible hoses with crimped end fittings at various locations
used on ALCO type DE Locos was published vide RDSO Modification No. MP-MOD-ES-03-08-
10

22.

High capacity buffers: To bring the capacity in line with those used on coaching stock, design of
high capacity buffers has been developed.

23.

Moatti type LO filter: These filters do not employ any replaceable elements and therefore do not
require any maintenance. In addition, the filtration efficiency is considerably higher. Report on
Evaluation of Moatti self-cleaning filter for lube oil filtration of diesel locos was published vide
RDSO publication No. MP. Misc 133 (Rev-00), Aug 2002)

2004

24.

Mycalex brush holder pins: Mycalex type brush holder pin are used successfully on GE
machines with total elimination of IR problem. This design has been implemented with very
encouraging results due to fewer problems during monsoon. Provision of Mycalex (Glass Bonded
Mica) type brush holder arms on traction machines was published vide RDSO Modification sheet
no. MP-MOD-EM-05-25-00 and Instruction bulletin No. MP.IB.EM.04.06.02

25.

LED type flasher light: RDSO has conducted a comparative study of conventional, Xenon and
LED type flasher lights and concluded that the LED type light is the best suited for our
application. Specification was published vide RDSO Spec No. ELRS/SPEC/FLASHER
LIGHT/0017 SEPT 04. Study on flasher light was published vide RDSO Publication No.
MP.Misc-127 April’2002.

26.

Non-asbestos arc-chutes: At present the arc chutes on contactors provided on locos are
fabricated from plates made of asbestos based material, which, being brittle, these arc chutes tend
to break during transit/handling. The problem gets aggravated during monsoon season when the
asbestos absorbs moisture and loses its mechanical and electrical strength. Moreover, asbestos
based insulating material has been banned worldwide due to health hazards. Moulded arc chutes
have, therefore, been developed based on non-asbestos based material having better mechanical
and electrical properties. These are based on non-asbestos glass fitted polymer resin bonded
composition. Specification and test programme of non-asbestos, non-hygroscopic arc chutes for
EP/EM contactors of diesel electric locos was published vide RDSO Specification No.
MP.0.23.02.01 Dec-99 (Rev-00) (Amendment No.1)

27.

Modified low loss low maintenance cooling water system: RDSO had conducted a study to
improve the cooling water system with a view to reducing losses in the system and augmenting
the heat removal characteristics. It has been decided to implement good features of the proposed
design and also borrow superior piping/clamping practice from GM locos, including
improvements like forged pipe unions/elbows to upgrade the system in respect of pressure loss
and maintainability. A comprehensive report on Up-gradations made in water-cooling system of
ALCO Locos was published vide MP.Misc-223 Nov’2009

28.

Relocated LED type marker Lights and GM type MU receptacles: The incandescent lamps
marker lights , which suffered from low life (further reduced due to vibrations), have been
replaced by LED type marker lights which is solid state type, comprising of cluster of power light
emitting diodes. It consists of sets of red and white LED's in such configuration that it provides a
good reliability and failure of one LED shall not result in the failure of the light. The location of
this light, along with the location and design MU receptacle, has been modified for superior
aesthetics and reliability. Markers light specification was published vide RDSO Specification No.
ELPS/MARKER/LIG/01

29.

High efficiency FTMBs with backward curved blades: With the switchover to self-cooled
rectifiers, it is possible to change the design of the FTMB suitably towards higher efficiency as

Draft

Document No:

Chapter –13 Technological Advancements

Version No: 1.0-d0

Date Issued: dd/mm/yyyy

Document Title: MANUAL MAINTENANCE FOR DIESEL LOCOMOTIVES

Revised 2013

Printed: 2015/03/08

Page 275 of 303

Description

Use

Since

the total cooling air requirement has gone down. RDSO specification No. MP.2400.11 (Rev-02)
Feb 09 issued incorporating low capacity 9500 CFM FTTM blower

30.

Case-carburized shot-peened gear/ pinion: Introduction of case carburizing TM gear & pinions
and shot peened root on WDG3A was mooted due to some reports of failure due to bending as
well contact fatigue. With these pinions, the problem has been eliminated.

31.

Open grain cylinder liners: With a view to reduce lube oil consumption and enhance service
life, these have been introduced.

2003

32.

Modified bogie for WDM3D/WDG3 series without weight compensation arrangement:
Based on the problems reported by sheds on this bogie, many short term improvements have
already been provided on the high adhesion bogie. As a long term improvement, this type of bogie
has been developed without the compensating and equalizing arrangement for microprocessor
based locos as all the long standing problems with equalizing/compensating beams are eliminated,
the loss in adhesion made up due to superior wheel slip control. Another feature in this design is
provision of CRU, instead of conventional cyl. roller bearings on journals for improved reliability
& reduced maintenance.

33.

Light Wt. TMs with roller susp. brg (92 days sch.): Light weight traction motors with roller
suspension bearing for extended maintenance schedules, reduced axle loads and lower un-sprung
masses has been provided, thus increasing the speed potential of the passenger locos and making
them more track friendly.

34.

Rivetless bearings for traction motor pinion-end: The reliability of the pinion end bearings of
TM’s has improved greatly with rivetless cage bearings.

35.

Improved fuel tank for WDG3A locos: The detachable fuel tank of suffers from the following
defects:
1. No provision of manhole leading to difficulties in cleaning, especially near suction pipe.
2. Different sizes for suction & return pipes making interchange difficult in case of any problem.
3. No provision of mesh near entry of fuel.
4. Draining difficult due to provision of dummy plug.
5.Glow rod has a tendency to become dirty and therefore unreadable
These aspects have been taken care of in an intermediate design, providing GM type level gauge
with a separate glass tube, which is not only a superior design but has better aesthetics & visibility
and replacement is also easy.

36.

Vibration-free LO centrifuge with standardized location & mounting: Tests at Pune diesel
shed showed that in case lube oil centrifuge is used on the loco, it increases the life of lube oil
filters by three times. The indirect benefits are longer life of piston, piston rings, liners, engine
bearings etc. Location of the centrifuge has been standardized near R1 & R2 location of the
engine, requiring modification to a door and pipelines etc. RDSO had issued spec. No.
MP.0.2600-9, (Rev-03) May, 2005 and maintenance inspection vide report no. MP.MI-28.( Rev-
00), Aug 2007.Subsequently this item was transferred to DLW as per instruction of Railway
Board letter no. 2002/M(L)/466/ 402/dated 08/09/2006

2005

37.

Single bolt design steel cap piston: In view of the problems of leakage of gases past six bolt
design, single bolt design pistons were developed.

38.

TM 4907 with roller suspension Bearing (92 days sch.): This project was conceived for
improved reliability and extended maintenance schedules.

39.

Upgraded compressor for enhanced schedule interval and overhauling: The upgradation
proposed envisages increased life of cylinder, piston rings, pistons, crankshaft, main bearings and
LO pump. The upgraded compressors are designed for 92-day schedule and 36 months overhaul.

40.

Longer life primary & secondary FO filter (92 days sch): The filter change for these filters is
required only after 92 days. The casting design has been modified to seamless pipe type casting to
avoid cracks.

41.

Nylatron bushings and liners for bogies: Nylatron is a thermoplastic material used extensively
on EMD locos in the bushings and line ring of bogies as it is strong & wear-resistant. Its use is
likely to help in increasing periodicity of bogie maintenance. This concept has been extended on
WDG2/WDM3D bogies also.

42.

Modified & relocated LO strainer: The LO strainer was relocated to facilitate removal of large
after coolers.

43.

Rubber cable cleats: The wooden cable cleats used on locos today are of poor quality and
design. So, it has been decided to switch over to rubber cleats on all locations as already used on
traction motors.

44.

GM type fastons instead of conventional TBs: The conventional TBs provided in the control

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