soochna march2011

7/25/2019 soochna march2011

1/166

2011 SOOCHNA MARCH 2 11

New feature :

Design Bulletins

WDG-5

Supplements on :

Dual Cab WDP4D locomotive

Wider Cab in WDP4/WDG4

Hotel Load System on dual cab WDP4B Distribution Power System

REMMLOT

Auxiliary Power Unit

Cab Air Conditioning

CCB on ALCO Locomotives

CCB-II on EMD Locomotives

Fabricated bogie frames for EMD

WDG5

Diesel Locomotive Works

Indian Railways

Varanasi

OUR LOCOS MOVE THE NATION


2/166

FOREWORD

It gives us great pleasure to release the 12th issue of Soochna. Earlier issues of

Soochna were published in March-02, June-02, December-02, April-03, March-04,

Sept-04, April-05, March-06 and April-07. In this issue we have tried to cover the

problem raised by Zonal Railways. The details of analysis and investigations and

final recommendations for design improvement and implementation by the

manufacturing facility, assembly shops and Zonal Railways have been covered in

this issue. In addition, this issue also contains a brief on various new technology

upgradation projects in hand at DLW. A special feature on the new locomotive

WDG5, which is likely to be rolled out in 2011-12 has been included to share the

knowledge with the Zonal Railways. New projects like:

Dual Cab

Hotel Load feature

Remmlot

Wider Cab

Fabricated Bogie version-II

Computer Controlled Brakes 2.0

APU

Cab air conditioning

have been covered in the current issue of Soochna.

DLW has started a practice of issuing Design Bulletins on various issues raisedby shops & zonal railways, which incorporates a detailed report on investigations,

analysis with recommendations for implementation by concerned agencies. A

compilation of all Design Bulletins issued by DLW, till date, has been included in

this issue of Soochna.

I request you to send your valued response on this issue of Soochna to help us to

consolidate the improvements in diesel locomotives manufactured at DLW.

Amit Kumar Agarwal

Chief Design Engineer

March 2011


3/166

INDEX

Section Description Page No.

A1 Special supplement on WDG5Locomotive 1 to 5

A2Dual cab WDP4D ( 4500 hp)Locomotive withindigenously developed AC-AC traction system

6 to 16

A3 Wider cab in WDP4/WDG4 Locomotives 17 to 19

A4Hotel Load System on duel cab WDP4B Locomotive(4500 HP)

20 to 28

A5Distributed Power System (DPS) for WDG4/WDP4BLocomotives (4500HP)

29 to 33

A6 Remote Monitoring & Management of locomotive &trains (REMMLOT) System

34 to 38

A7 Auxiliary Power Unit (APU)39 to 44

A8Cab Air Conditioning units on Diesel Electric

Locomotives45 to 47

A9 CCB system fitted on ALCO Locomotives48 to 50

A10 CCB-II system fitted on EMD Locomotives

51 to 53

A11 Fabricated Bogie Frames for EMD Locomotives54 to 56

A12 Special supplement on Design Bulletins57 to 124

B Compendium of failure investigations125 to 150

C Summary of Important Change Notices151 to 156

DList of important CPAs (corrective and preventiveaction) under ISO-9001

157 to 159

E List of trial fitments by DLW160 to 163


4/166

Section A1

Special Supplement on

WDG5 Locomotive

- 1 -


5/166

- 2 -

WDG5 Powering Progress

Indian Railways is actively looking for ways to enhance the horse power of its currentfleet to meet the current demand for higher horse power locomotives to address the growingneed for hauling heavier trains and higher throughput. With the intention, Indian Railwaysevaluated various options to enhance the horse power of EMD design locomotive beingmanufactured in DLW from 4000 HP to 4500 and subsequently to over 5000 HP.

Indian Railways had entered into a TOT contract with M/s EMD/ USA in 1995, whichincluded a transfer of technology for manufacture of WDG4 locomotive and also included atransfer of technology for EMDs 5000+hp 20 cylinder 710 series engine (locomotiveapplication only). Since, for present 16 cylinder engine is not capable of being upgradedbeyond 4500hp, it was deemed that the 20-710 engine would be ideal platform for enhancingthe current power of the WDG4 to 5000+hp.

The 5500 HP design of EMD locomotive, called WDG5 has been developed jointly byEMD and IR. It brings to IR advanced technologies such as Electronic Fuel Injection (For

higher duel efficiency and emission control), Electrically Driven Auxiliaries (for higher reliabilityand energy efficiency) and user friendly driver console FIRE amongst other state of the arttechnologies. Both DLW and RDSO have been active partners in the design of this uniquelocomotive which provides enhanced 5500 HP within the constraints of axle load.

The design of the WDG5 is a logical and technological extension of the know howoriginally procured by IR from EMD. It also significant that the 5500 HP version of diesellocomotive as developed jointly by IR and EMD, is unique in the world where the standardconfiguration of power in modern freight locomotive is either 4000/ 4500 or 6000.


6/166

- 3 -

KEY FEATURES

High Performance AC Traction - 5500 BHP* for Freight Operation 20-710G3 Engine w/ Electronic Unit Injection Cab Design with EN12667 Collision protection & Ergonomic Control Consoles Gen3 FIRE Functionally Integrated Railroad Electronics Compliant to AAR S590,

AAR S591 Display & Environmental Standards & Industry Standards EM2000 Microprocessor Control System Inverter driven cooling fans & truck blowers for Optimized performance Microprocessor Controlled Air Brakes High Adhesion, Bolsterless, Weld Fabricated Three-Axle Bogies

Pioneering design of lightest fabricated bogie on high horsepower Diesellocomotives

Minimum 90 Day Maintenance Schedule Operator amenities including Air-conditioning, Heating & Toilet Optional IntelliTrain Remote Monitoring System

PROVEN 710 ENGINE TECHNOLOGY

20 Cyl - 710 Engine Delivering5500 BHP*

Electronic Fuel Injection WithEMDEC

Proven Service and ReliabilityPerformance

High Efficiency Turbocharger Green Technology

Fuel Efficient & ReducedEmissions Capable

Fiberglass Bag-Type 184 Day AirFilters

EMD Automatic Engine Start/Stop(AESS) System Integrated IntoEM2000 Provides:o Fuel Savingso Noise Reductiono Reduced Emissions

Single Push Button Air Start fromCab

* R Conditions


7/166

- 4 -

IMPROVED VEHICLE STRUCTURES

High Capacity Fuel Tank- 7500 Liters

High Capacity Buffer Light weight- Car body access doors for ease of maintenance

Underframe mounted Sand Boxes of wDG4 loco pattern

Under Slung Battery Box with Ni-Cad batteries

Deep well type design of high strength lighter weight Underframe to restrict the height ofLocomotive well within MMD of Garib Rath profile.

CREW FRIENDLY CAB

EN12667 Compliant Collision Protection Improved Visibility Cab Dual Control Consoles - Ergonomic

Layout Service Proven, TFT FIRE Display

Screens Replace Analog Gauges Compliant to AAR S590, S591 Display &Environmental Standards&Industry Standards

Heated Windshields for Defogging Air Operated Windshield Wipers Roof Mounted Air-Conditioning &

Heating unit Thermo-acoustic insulation in cab walls

Garib Rath Profile


8/166

- 5 -

STATE OF THE ART BOGIE & TRACTIONTECHNOLOGY

High Traction, Bolsterless, 3-AxleBogie

High strength Low weight weldfabricated bogie frame design

90: 21 Gear Ratio provides up to 105KMPH

1092 mm (43) Wheels with 2-1/2 RimThickness

Class K Journal Bearing 2 Piece Bearing Adapter for ease of

wheel set removal Unitized Parking Brakes Bogie Design incorporates Minimal

wear surfaces ReducedMaintenance

IMPROVED ELECTRICAL TRANSMISSION

TA20 / CA9 Generator New Technology - Combined E-locker

with IGBT Inverter Technology, APCinstead of Auxiliary Generator;EMDEC Control for EUI

High Performance A2921-6 ACTraction Motors

Compact Radial Dynamic Brake Grids Self load Test Locked Wheel Detection

IMPACT ON OPERATION

The 5500 HP WDG5 is primarily aimed at improving the throughput with higher balancingspeed. The locomotive will be able to achieve 90kmph speed on level track with 59 BOXN(CC+8+2) loads. (WDG4 is able to achieve 80kmph). It can pull all other loads at 100kmph.The locomotive also increases the starting load ability. The BOBRN loads which cannot bestarted with a single loco on 1 in 150 grade can be pulled by WDG5.

The locomotive takes the crew safety and comfort to the next level. It provides forEN12667 compliant cab collision protection. It introduces TFT screen based FIREdisplay. Besides providing for HVAC air conditioning for crew comfort it introducestoilet for the first time. It has improved visibility through an enlarged MMD and also byimproving the profile towards long hood. The loco also provides for de fogging forimproved visibility.

PRODUCTION PLANS

Design of this WDG5 locomotive has been finalized jointly by DLW, RDSO &EMD. It isexpected that first prototype of this loco will be ready by Nov2011. Ten such locomotives areplanned to be turned out in the next two years.

*****


9/166

Section A2

Dual cab WDP4D Locomotive

(4500 HP) with indigenously

developed AC-AC traction system

- 6 -


10/166

- 7 -

FIRST EVER 4500 HP DUAL CAB WDP4D LOCOMOTIVE WITH INDEGENEOUSLY

DEVELOPED AC-AC TRACTION SYSTEM

INTRODUCTION:

Indian Railway started their Dieselization programmed with setting up of Diesel

Locomotive Works, Varanasi in 1961. DLW produced first Diesel Locomotive in 1964 withDC-DC traction system. Since then, DLW constantly kept on upgrading the dieseltechnology (DC-DC to AC-DC then AC-AC GTO and now4500 HP AC-AC IGBT) to meetgrowing needs of Indian Railways.

In its quest for the State of the Art Technology, Indian Railways signed a TechnologyTransfer contract with Electromotive Division of General Motors of USA in 1995. With thisTOT, DLW started manufacturing Three Phase AC-AC (GTO based) locomotives in 2002.

GTO Technology based AC-AC traction converters have certain disadvantages like bulkysize, excessive cooling, slower switching time etc. In year 2005, it was decided to adoptIGBT (Insulated Gate Bipolar Transistor) based Traction Control converters replacing the

phasing out of GTO technology and to gain the advantages of new IGBT technology. Thefirst upgraded power 4500HP IGBT (EMD make) technology WDG4 locomotive no.(12114) was manufactured and turned out in May 2007.

A pilot project for development of Dual Cab WDP4D locomotives was initiated by RDSOas directed by Railway Board, a project for indigenous design & development of AC-ACtraction system and electrics for WDP4D locomotive was undertaken by DLW in Yr.2008-2009. Accordingly a developmental order for 2 loco sets for WDP4B Dual Cab 4500HP

AC-AC traction system with Control Console was placed on M/s Medha in May09 forfully indigenized technology consisting loco control computer and traction converters (LCC with HVC +TCC+ECC2+ECC3 & ECC#4).

The Dual Locomotive control is based on BL (button lever) Key concept of ElectricLocomotives. Each CAB has a BL Key. Existing CAB (SH side) is named as CAB#1 andnew CAB (LH side) is named as CAB#2. If both BL keys are OFF, Locomotive isisolated. If both BL keys are inserted simultaneously, still Locomotive is isolated. TheCAB where the BL key is inserted is considered as an Active CAB. CAB#2 has aMiniature ECC#1 panel named as ECC#4. Control Console in both CABs will beidentical. In the Control Console, Master Control and Switches are active only afterinsertion of BL key. In ECC#1 VFD display is removed. Each CAB has 2 TFT LCDdisplays one for main driver and another one for assistant driver. These two displaysshow same data. Battery Ammeter is not duplicated in CAB#2 as this information is

available on TFT LCD display.

OBJECTIVE OF DUAL CAB WDP4D LOCOMOTIVE:

The main purpose of development of WDP4D-Dual Cab locomotive is for solving driversvisibility problem during driving of locomotive with long hood side (rear side) leading.

SCHEDULING OF THE PROJECT:


11/166

- 8 -

In 2008 instruction received from railway board to undertake the development ofDual Cab locomotives with complete AC-AC traction system through a singlesource.

Preparation of tender specification and tendering process etc was started in 2008-09.

Order was placed on M/s Medha for development of complete AC-AC TractionSystem for 2 loco sets in May09.

Projects first Kick off Meeting was held on June08 for supplying various drawings,their details etc. Further project plan & schedule date of completion of variousactivates were finalized.

First Milestone review Meeting was held in June09 for discussing TFT displayscreen, newly design Control Console and interfacing CCB with MAS696 and toevaluate the progress on the project,

Second Milestone meeting was held in July09 for review & finalization of Analoggauges shifted to TFT screen, schematic and duplicated ECC#1 switch panel & CBin Cab#2.

Development progress meeting was held between Medha & DLW at DLW on date-16/07/09.

Prototype inspection of AC-AC traction system for Dual Cab locomotive wascarried out in March10.

Prototype AC-AC traction system & Control Console supplied to DLW on dated 22

March10.

Fitment of equipment on Loco no. WDP4D-40014 at DLW in June 2010.

Testing of locomotive no. WDP4D-40014 completed at DLW in August 2010.

Prototype WDP4D, 40014 & Second WDP4D, 40026 were turned out from DLW toNR/TKD on dated 9th Oct 2010 & 28thDec 2010 respectively.

Recently necessary field testing has been carried out by RDSO for issuing thespeed certificate.

Further Railway Board vide letter no. 2004/M(l)/466/1505(4000-4500) dated23/04/2010 has advised DLW to manufacture another 10 no Dual Cab locomotivein financial year 2010-11, for which tender has opened on 21/01/201.


12/166

- 9 -

26 Ma 09

24tJune08

29 Oct08

14t

& 16tJul 09

18 Dec09

22n

March10

10 June10

04 Au 10

17tAu 10

09 Oct10

8 March10

28 Dec10

ROAD MAP OF THE PROJECT:

Board Instruction

Placement of PO.

Kick off Meeting

First Mile stone Meeting

Development Status Detailing Meeting

Type testing of prototype system

Arrival of First System to DLW

Starting of Fitment in Loco no. WDP4D-40014

Starting of Loco no. WDP4D-40014 Testing

Completion of Loco no. WDP4D-40014 Testing

Dispatch from DLW of Prototype WDP4D-40014

Dispatch from DLW of Second WDP4D-40026

.`


13/166

- 10 -

SALIENT FEATURES OF DUAL CAB LOCOMOTIVES:

4500 HP Locomotive for Passenger operation Locomotive operation from both (Front & Rear) Cab Two driver cabins with one full width control console in each cabin. Each full width control console provides two TFT (Thin Film Transistor) Display one

each for loco pilot and his assistant The Dual cab Locomotive control is based on BL (Button Lever) Key concept of

Electric Locomotives. Each CAB will have a BL (Button Lever) Key. Existing CAB(Short Hood side) is named as CAB#1 and new CAB (Long Hood side) is named asCAB#2

The cab in which BL (Button Lever) key is inserted and turned to 'ON', is called Activecab. We can operate the locomotive from Active cab only.

710 GB Engine with WW Governor Indigenous AC-AC Traction System ECC#4( New mini ECC#1 in rear cab for Loco operation) Microprocessor controlled Brakes Provided with 6 MAC TM with gear ratio 77:17 Wider Cab 54" Radiator Fan Flexibility to provide REMMLOT & DPS in future

WDP4D BOGIE AND TRACTION TECHNOLOGY:

High Traction, High Speed Bolster less ,3 axle bogie High strength-low weight, fabricated (Fab -II) bogie frame Two stage suspension, primary soft coil spring & secondary stiff rubber spring Centre pivot- Four bar mechanism Journal bearings- F class-CTRB Unidirectional TM arrangement for high adhesion Yaw damper provide yaw stiffness for tracking stability

WDP4D CONSOLE WITH TFT DISPLAY INTREGATED:

Two TFT displays in each Control Console provided in both cab TFT replaces Speedometer, TE/BE meter, and all mechanical gauges

WDP4D GENERAL SPECIFICATION:

Locomotive weight-1232% T Nominal Axle Load -20.5 T 5000 Fuel Tank Capacity Co-Co Axle Configuration Broad Gauge Locomotive


14/166

- 11 -

WDP4D PERFORMANCE SPECIFICATION:

4500 HP Gross Horse Power 460 KN Starting TE 230 KN Dynamic Brake Effort 130 Kmph maximum operating speed

22.5 Kmph minimum continuous speed

CAB1 ECC#1

TCC

ECC#2

Line Sketch of Dual Cab locomotive

Major Electrical Components of WDP4D-Dual cab locomotive:

Electrical control cabinet ECC#1 including Locomotive Control Computer(LCC) Electrical control cabinet ECC#2 Electrical control cabinet ECC#3 Electrical control cabinet ECC#4 (new introduced ) Traction control cabinet TCC including Traction Computer(TC) Control Console for CAB1 (new) Control Console for CAB2 (new) Loco Control Computer (LCC)

Electrical Control Cabinet ECC#4(newly introduced):

The panel which is provided in CAB#2 is named as ECC#4. This is a Miniature form ofECC#1 panel.

CAB2


15/166

- 12 -

ECC#4

Components of ECC#4:

To enable loco operation from rear cab, an additional ECC#4 is introduced which look is

similar to start panel of ECC#1. The item contained in ECC#4 are also available inECC#1.The main items of ECC#4 are:

Micro Air Brake Circuit Breaker MAB CB Computer Control Circuit Breaker Fuel Prime/Engine Start switch FP/ES Isolate / Run Switch Emergency fuel Cut Off Switch EFCO BL Key TELIMIT Switch RAPB/AEB Enable Switch

Classification lights switch GRNTCO switch Alerter Alarm Memory Freeze Switch Cab Fans & Lights Circuit Breaker Generator Field Circuit Breaker GFCB

Micro Air Brake Circuit Breaker MAB CB:

These two switches are connected in series if both the switches are on then only CCB getsSystem gets power supply. Even though MAB CB is On in CAB1 MCC will gets this digital i/p.

if and if only MAB CB in CAB2 is ON.

MAB CB CAB1 MAB CB CAB2 System Action

OFF/ON OFF CM : MAB CB OFF in CAB2

OFF ON CM : MAB CB OFF in CAB1

ON ON Normal Working

Note: CM = Crew Message.

Computer Control Circuit Breaker:


16/166

- 13 -

In each cab one Computer Control Circuit Breaker is available, both are connected in series.From any cab power supply can be recycled.

Fuel Prime/Engine Start switch FP/ES:

It is provided in both the CABS in parallel. If any switch is kept in prime position MCC will getPRIME digital i/p. If any switch is kept in START position MCC will get START, PRIME digitali/ps.Note: Engine can be started from any Cab.

Isolate / Run Switch:

It is provided in both the CABS in any CAB if the switch is kept in Isolate position then Brakecontactors will gets supply. So in inactive CAB it should be kept in RUN position. If anyswitch is kept in Isolate position then MCC gets Isolate digital i/p, If both the switches arekept in RUN position then only MCC gets RUN digital i/p.

Note: Engine can be isolated from any Cab.

Emergency fuel cut Off Switch EFCO:

It is provided in both the CABS in series. If any switch is pressed MCC will get NOEFCOdigital i/p.

Note: Engine can be shutdown from any Cab.

BL Key:

In each CAB provision was given to insert BL Key. If BL key is inserted in any one CAB thatis treated as active CAB. In case either BL key is inserted or not inserted in both the CABsthen system will be isolated and corresponding CREW Message will be given. BL Key statusis monitored by MCC thru BL Key1, BL Key2 digital i/ps.

BL Key Interlocks:

Alerter Reset Push Button RAPB / AEB TE Limit Switch

GF Request Switch Horn Control and Fuel Pump Switch Manual Sand Switch. Forward & Reverse inputs


17/166

- 14 -

BK Key & GFCB related crew messages:

BL Key1 BL Key2 GFCB

CAB1

GFCB

CAB2

System Action

OFF OFF ON/OFF ON/OFF Brake Contactors ON, GFOFF.CM : BL Key Removed In Both CABs

ON OFF ON OFF Normal Working from CAB1CM : CAB1 is Active

ON OFF OFF OFF GF OFF.CM : CAB1 is ActiveCM : GFCB Open in CAB1

ON OFF ON/OFF ON GF OFFCM : CAB1 is ActiveCM : GFCB should be OFF in CAB2

OFF ON ON ON/OFF GF OFFCM : CAB2 is ActiveCM : GFCB should be OFF in CAB1

OFF ON OFF ON Normal Working from CAB2CM : CAB2 is Active

OFF ON OFF OFF GF OFFCM : CAB2 is ActiveCM : GFCB Open in CAB2

ON ON ON/OFF ON/OFF Brake Contactors ON.CM : BL Key Inserted In Both CABs

TELM Switch:It is provided in both the CABs in parallel thru BL key. In any CAB if it is made ON andcorresponding BL key is inserted then MCC will get TE Limit digital i/p.

RAPB/AEB Switch:It is provided in both the CABs in parallel thru BL key. In any CAB if it is made ON andcorresponding BL key is inserted then MCC will get RAPB digital i/p.

Classification lights switch:It is provided in both the CABs. In any CAB if the switch is kept in CE position then CE side

White light, HE side Red light becomes ON. In any CAB if the switch is kept in HE positionthen HE side White light, CE side Red light becomes ON.

GRNTCO switch:This switch is provided in both the cabs in series. If both the switches are closed then onlysystem gets the digital i/p (only 1 i/p which is existing) and treats GR protection scheme isenabled.

Alerter Alarm:


18/166

- 15 -

It is provided in both the CABs. When ever MCC makes Alerter Alarm digital o/p ON, both willsound.

Memory Freeze switch:It is provided in both the CABs in parallel. In any CAB if it is ON then MCC will get MemoryFreeze digital i/p.

Cab Fans & Lights Circuit Breaker:It is provided in both the CABs. In CAB1 it proved supply to CAB fans only, In CAB2 itprovides supply to both Cab Fans & Cab Lights. If the CAB fan CB is ON in CAB2 then Left &Right CAB fans and CAB lights gets supply (corresponding switch should be ON)

GF Circuit Breaker:It is provided in both the CABs in parallel. In working CAB it should be closed and in nonworking CAB it should be open.

GF CB related Fault Messages:

If GFCB is tripped in CAB1 then MCC logs Generator Field CB Tripped Under load inCAB1 fault.

If GFCB is tripped in CAB2 then MCC logs Generator Field CB Tripped Under load inCAB2 fault.

Control Console (Front & Rear Cab):The compact control console made of FRP One nos. Control Console has fitted in Cab1 &another is Cab2.


19/166

- 16 -

Components of Control Console:

TFT (Thin Film Transistor) display Alerter warning Light Head Light Switch ( Isolation sw type) GF Request Switch Engine RUN Switch Dynamic Brake Circuit Breaker Control and Fuel Pump Switch Auto Flasher Switch Alerter Reset Switch MUSD Switch Attendant Call Push Button switch Manual Sand Switch AEB Reset Push Button switch Horn Push Button switch

TFT (Thin Film Transistor) Display:

Two TFT displays (one for driver & another for assistant driver) has been provided ineach cab control Console.

*****


20/166

Section A3

Wider cab in

WDP4/WDG4

Locomotives

- 17 -


21/166

18

Implementation of Wider Cab in WDGP4/WDG4 locomotives

Problem

South Western & Central Railways have raised the problem for poor visibility in Long hood

driving of WDP4/WDG4 locomotives.

Action taken by DLW

This problem has been studied in detail at DLW from the feasibility of design point of view

and the cab structure drawing was reviewed in which both side walls of cab structure wasextended outside up to the end point of earlier way window i.e. 3200 mm width. In that case

rear portion of the cab was made 3200 mm wide well within the MMD to facilitate clear

visibility in longhood drive to the crew and way windows were eliminated in new design.Accordingly, the cab doors design were revised by increasing the size of looking glass from

371 to 486 mm and shifting driver seat outwards. The improved visibility during longhood

drive can be seen from the sketch given below

The above design was forwarded to RDSO vide this office letter no. dlw.m.65.211.3 dated17.11.2007 for examining its feasibility. RDSO, vide their letter no. SD.Dev.L.GM.Loco

dated 06.11.07, agreed to the suggested drawing. However, RDSO suggested stream line

contour cab (i.e. aerodynamic profile) as shown in 3-D picture given below instead of sharpcontour as being previously manufactured at DLW.


22/166

19

The above design, however, required major modification in all the previous fixtures formanufacture of the cab as this design involved lot of cylindrical and other complex curve

segments. Accordingly to expedite the implementation of this design, DLW have taken a

conscious decision to initially procure these cabs from trade and gradually switch over to in-house manufacturing after modification of the previous fixtures.

Apart from the above, the top of underframe beneath the cab was also required to be widenedaccordingly. Due to this reason, the front sand box, piping and electrical wiring connecting

both control desk was modified. Also, side windows, door frame and both cab doors were

re-designed and procured from trade.

The front view of 3-D model of the locomotive can be seen below -

.

Implementation

The first wider cab was fitted in the month of June, 2009 in loco no. 12222 dispatched to

NR/Lucknow and regular implementation started from April 2010. Now, wider cab isbeing fitted in all WDG4/WDP4B locomotives.

*****


23/166

Section A4

Hotel Load System on

dual cab

WDP4B Locomotive

(4500 HP)

- 20 -


24/166

- 2 1 -

FIRST EVER 4500 HP WDP4B LOCOMOTIVE WITH HOTEL LOAD SYSTEM

INTRODUCTION:

The hotel load, i.e. electrical power used to operate the lights, fans, air-conditioning, water

raising apparatus and the pantry equipment of the coaches of trains, has been traditionally

supplied through generation by the coaches themselves. Every coach has the power generationequipment consisting of under-slung alternators driven by axle mounted pulley through `V belts

and large capacity batteries. This is termed as the self-generating (SG) system. At present, all the

Mail & Express trains, other than the Rajdhani and Shatabdi trains, are running with AC coaches

provided with the SG system.

Rajdhani and Shatabdi Express trains use the other alternative method of supplying this energy

from two power cars fitted with diesel alternators, placed at the two ends of the rake. The method

of supplying power from the two coaches at either end is termed as end-on-generation (EOG).

DIFFERENT TYPES OF HOTEL LOAD SYSTEMS IN INDIAN RAILWAY:

Head-on generation (HOG)- is a term used for supply of power for hotel load from thelocomotive. In principle, it is a variation of EOG system where the power for hotel load is takenfrom the locomotive instead of the end coaches. The diesel engine will supply hotel load power

at 750V, 3-phase, 50 Hz A.C. through feeders, which run throughout the train. This system is

still under development for the diesel and electric locomotives.

SG Systems - In the non-AC coaches, 110V D.C. is generated by one 4.5 kVA alternatorrectifier-regulator set per coach. 110V A.C. is also being used now. Each coach is provided with

a 110V, 120 AH battery. The air-conditioned coaches are equipped with two 25 kVA pulley-

driven alternators generating 440V 3-phase A.C. Each coach has a 110 V, 1100 AH battery andtwo inverters.

EOG Systems -The power cars supply power at 750V, 3-phase, 50 Hz A.C. through feeders,which run throughout the train. This is stepped down to 415 V 3-phase A.C. for air-conditioning

and 110V A.C. or D.C. is used for lights and fans

.

DEVELOPMENT OF 4500 HP WDP4B LOCOMOTIVE WITH HOTEL LOAD SYSTEM:

As per Railway Board guide line 10 nos. WDP4B Locomotives are to be manufacturedwith 6 TM configuration and Hotel Load feature.

DLW PO 060980150.060980150 dt 31.08.09 placed on M/s Medha for supply of two no.Hotel Load inverter & DPS.

Two WDP4B locomotives no 40001& 40003 has been manufactured by DLW with HotelLoad & DPS feature against above PO and both locomotives dispatched to AMV shed on

20.04.10 for field trial by RDSO. Presently both Locos are homed at TKD shed. Filter

circuit of Hotel load inverter output is being modified by M/s Medha, and is under testingwith RDSO.

Recently DLW has placed POs for balance 08 nos AC-AC traction system, integratedwith Hotel Load along with DPS for WDP4B locomotives, on M/s Siemens & M/s

Medha for 6 nos. & 2 nos. respectively.


25/166

- 2 2 -

FUNCTIONAL DESCRIPTION & SALIENT FEATURES OF M/S MEDHA MAKE

HOTEL LOAD SYSTEM:

The complete hotel load inverter along with hotel load computer is supplied in anothercubical (MIN504) (Existing ECC#2 cabinet). The existing ECC#2 parts are

accommodated in ECC#1. The control of hotel load buck chopper and inverter is done

with the hotel load computer (MIC 694). The system control data related to hotel load iscommunicated between LCC in ECC#1 and hotel load computer with OFC cable. A

redundant OFC cable is also provided for this purpose.

Under frame modified for fitment of Hotel load accessories. Another modification w.r.t.WDP4B are elimination of ECC2( Items adjusted in ECC#1), BA Box ( Two rows

arrangement with sliding platform) and 5000 Lt smaller fuel tank.

The Hotel load supply of 750 V, 3 phase AC supply fed to coaches from a diesel powercar through IV coupler.

The power for the Hotel load converter is derived from DC link of the locomotive .Firstly

Power from DC link fed to Buck Chopper then to Inverter Panel. The Inverter receivespower from DC link (through Buck Chopper) with a voltage varying from 1100V to 2600V and provide a suitable output supply at 7505%, 3 phase 50Hz The hotel Load

Converters is rated for 500KVA power which is compatible with existing EOG Power

cars.

The Following protections are provided in hotel load system:

Line to line short circuit at load

Earth fault

IGBT short circuit protection

Heat sink over temperature

Gate drive fault

High and low DC link voltage

Dc link short circuit

Input and output over current

Transient discharge current

Reverse polarity

The following information is displayed on the drivers display (Existing locomotive

computer VFD display):

Line to line voltages

Currents in all three phases

Line to line short circuit indications

Earth fault

Shoot through fault


26/166

- 2 3 -

Heat sink over temperature

Gate drive fault

Overload

Fault diagnosis and trouble shooting of hotel load module is provided similar to the faultdiagnosis system of traction inverter module.

Two blowers used for buck chopper and inverter (one for each) are placed in the cleanroom of the loco (behind the traction converter). The three phase input power is taken

from Hotel Load Inverter.

The hotel load power from the inverter on the loco to various coaches is fed through twofeeders (one at left and other at right side of the coaches) running parallel to the rack at

750V, 3 phase, 50 Hz supply. Feeders of the adjacent coaches are connected through

standard IV (inter-vehicular) plug/socket arrangement.

The two four pole contactors one for each feeder are arranged in separate cubical (MCA

754) along with Feeder over Load (FOL) and Feeder Earth Leakage (FEL) relay moduleson each feeder. The 750V, 3 phase supply is connected to the two feeders using these

four pole contactors.

Automatic interlocking and feeder selection system is used to energize either feeder orboth the feeders from only one side (either hotel load inverter or power car) at a time.

The feeder contactors are operated based on the feeder selection state and the interlockingand feeder fault conditions.

The power car circuit consisting of feeder interlocking and feeder fault circuit isdeveloped with relay logic which is compatible with the existing arrangement on EOG

trains. This circuit is housed in ECC#1.

The feeder operating control objects for both feeders 1 and 2 listed below are placed on

the ECC#1 cabinet front door and are similar to existing display arrangement on EOGtrains. This display panel is very convenient to the driver to manage the feeders power.

Master controller four position switch for feeder selection.

Feeder ON push button for both feeders along with light indication.

Feeder OFF push button for both feeders.

24 V DC supply switch and DC ON LED indication for both feeders.

Fault test push button for fault circuit testing for both feeders.

Feeder over Load (FOL) and Feeder Earth Leakage (FEL) fault indications for

both feeders. Hooter common for both feeders fault.

Hooter OFF push button to acknowledge the Hooter and Fault LED indication forboth feeders.

Fault Bypass switch in both feeder circuits.

Fault Reset button for both feeders.


27/166

- 2 4 -

MAJOR ELECTRICAL ITEMS OF M/S MEDHA MAKE HOTEL LOAD SYSTEM:

Buck Chopper Assembly

Inverter Assembly

Blower Assembly

Contactor Assembly

User Interface Panel mounted on ECC#1 in Driver Cab .

Buck Chopper Assembly:-

The input to the buck chopper is taken from ECC#1 through an isolation switch which isprovided in ECC#1

Output of the hotel load buck chopper is maintained at 1050 V for all DC link voltages

from 1100 V to 2800 V The constant 1050 V DC is used as input to the hotel load inverter.

It consists two IGBTs in parallel and two free wheeling diodes in parallel

Ratings of IGBT and diodes: 6.5 KV, 600

Inductor and capacitor are used as low pass filter before feeding the inverter

Hotel load input DC link current is measured using bipolar hall effect current sensor withrating 1200 A to provide reverse polarity protection

Firing signals to buck chopper IGBTs are given by Hotel load computer through OFC

Hotel load Buck Chopper


28/166

- 2 5 -

Inverter Assembly:-

Hotel Load Inverter

Hotel load Inverter Consists of

Input capacitor

IGBTs (6 No)

Output inductor filter

Hotel Load computer

Various sensors

Derives 3 ph 750 V, 50 Hz from fixed 1050 V DC

Input capacitor is used to smooth out the DC ripple

Output di/dt inductors are used to limit the rate of rise of output current

Here an auto transformer is used to generate 3 ph 415 V AC to power blower motors

used for forced cooling and also to provide a neutral point to the load

Hotel load computer issues the firing signals to IGBTs to maintain constant outputvoltage

Rating of IGBTs is 1200 A, 2500 V

Pulse by pulse status of the IGBTs are monitored by hotel load computer

Hotel Load Computer consists of following Cards-

MHLPS Power supply module

MHLOFC OFC interface with IGBTs

MHLCC Control Computer

MHLAIP10#1 Analog input card 1




29/166

- 2 6 -

Blower Assembly:-

Two 3 ph, 415 V blower motors are provided for forced air cooling of buck chopperIGBTs, free wheeling diodes, and hotel load inverter IGBTs.

Auto transformer is used to generate 3 ph 415 V AC to power these blower motors

The two phase currents of the blower motor are monitored by the hotel load computer.

Hotel Load Blower

Contactor Assembly:-

To maintain the compatibility with exiting EOG two feeders are provided.

These feeders are connected to the hotel load inverter through feeder contactors.

Each of these contactors is a four pole contactor.

On each feeder one earth leakage and one feeder overload relay module are provided.

Two sets of cables (three phase lines, one neutral, one earth, two feeder control lines) arerun from each feeder contactor in this cabinet to the two ends of the locomotive to

connect with the Inter-vehicular couplers.

Hotel load Contactor


30/166

- 2 7 -

User Interface Panel mounted on ECC#1 in Driver Cab:-

Five indication lamps which shows status of HL converter showing-

HL inverter input ON

HL inverter ON

Inverter Fault

Inverter Earth fault

Inverter Over load

Hotel load User Interface Panel


31/166

- 2 8 -

Hotel Load scheme with Siemens AC-AC Traction System:

Recently DLW has placed POs for 06 nos. AC-AC traction system, integrated with Hotel Load

along with DPS for WDP4B locomotives, on M/s Siemens. Proposed Hotel Load scheme withSiemens AC-AC Traction System is mentioned below:

Functional Description:

Hotel load inverter is a part of TCC itself. This Hotel Load inverter shares common DC-Link

power as used by traction inverters. The operation of Hotel load during motoring and dynamic

braking is as follows:

DC link voltage input to Hotel Load inverter is maintained at bare min. and varies up to 2800V

DC. The Hotel Load inverter module converts this DC Link power to 3- AC 750 V / 50 Hzoutput through firing pulses. This 3- AC output is then applied to transformer for Isolation to

ensure passengers safety. Output of the transformer is then fed to the Hotel load switchgear

cabinet which houses various switchgears, Current and voltage transducers and variousprotection systems for ensuring safe working of Hotel Load. Eventually output is then fed to IV

couplers through switchgears / contactors.

There are total 4 IV couplers on a locomotive, two on each front and back side of the locomotivefor connecting 3- AC output to the feeder lines. These feeder lines in turn provide 3- AC to

transformer of the coach which in turn converts this to 415 V 3- AC outputs which is used for

power supply to the coach load.

With the use of brake chopper inside TCC, we are able to divert dynamic brake power to Hotel

Load requirement thus bringing in energy saving and efficiency in whole system.

*****


32/166

Section A5Distributed power system

(DPS) for WDG4/WDP4B

Locomotives (4500HP)

- 29 -


33/166

- 3 0 -

FIRST EVER DISTRIBUTED POWER SYSTEM (DPS) FOR 4500 HP

WDG4/WDP4B LOCOMOTIVES

INTRODUCTION:

On Indian Railways goods trains run on Ghat sections which are as steep as 1 in 37 and 1 in 50.Many times it requires 6 to 7 locomotives to haul goods trains on these steep gradients. Due to

limitation of coupler capacity, all the locomotives could not be attached in front of the train. It

is proposed to work the goods trains with three locomotives consists placed at the front, middleand rear of the train. A remote control system for locomotive through a wireless link is,

therefore, developed for controlling locomotives placed in the train consist from the leading

locomotive. This system is called Distributed Power Control System. DPS also enables toenhance the passenger train capacity in train set formation for quick reversal on the same track

and platform. DPS also finds a use where running freight loads in a short circuit where there is

reversal constrains at either ends.

DEVELOPMENT OF DPS SYSTEM FOR WDG4/WDP4B LOCOMOTIVES:-

A developmental PO was placed on M/s Medha /Hyderabad for Indigenous design,development supply and testing of AC-AC traction system and electrics for WDG4locomotive to RDSO spec no. MP.0.2400.38 for 2 Loco sets with Distributed Power

Control and 2 loco sets of WDP4 on M/s Medha. M/s Medha has supplied the 02 loco set

of AC/AC traction system with Distributed Power Control and fitted on WDG4-12169 &WDG4-12189 and performing satisfactorily.

Further a P.O. No.060980150.09280721 dated 31.08.2009 was placed on M/sMedha/Hyderabad for 02 nos. Distributed Power Control system along with additional

Hotel Load Inverter. The supplied Distributed Power Control system against this P.O was

fitted on WDP4B-40001 and WDP4B-40003 with Hotel Load and tested at DLW.Presently both locomotives are homed at TKD/NR Railway.

As per Railway Board directives, procurement of 60 nos DPS is under process.

Recently, DLW has placed POs on M/s Siemens & M/s Medha for procurement of AC-ACtraction system, integrated with Hotel Load along with DPS for 6 nos & 2 nos respectively.

SALIENT FEATURE OF M/S MEDHA MAKE DPS SYSTEM:-

Synchronous Wireless Communication for a distance of 1.5Km.

Braking Actions from Multiple Locomotives in the formation.

Making the different locomotives in the formation to work with different powers.

Air Flow sensing mechanism in case of wireless communication failures.

Locomotive can be used as Lead or Remote.

Detection of Break in continuity or partitioning of Train formation.

Operated in UHF Band

FUNCTIONAL DESCRIPTION OF M/S MEDHA MAKE DPC SYSTEM:-

DPC system is developed by M/s Medha as per the RDSO Specification No.MP.0.04.02.03 (Rev 0) October-2005 & it is compatible with M/s Medha AC-AC raction

system MAS 696.


34/166

- 3 1 -

This system is used to communicate with two or more Locomotives in the formation placedremotely to each other for Synchronized running of the Locomotives to allow Operation ofLonger Train.

Remote Locomotives are controlled and operated from the Lead Locomotive.

Communicates with other similar system in the formation for exchanging the Control,operating and Status signals for running the formation and displaying the status in the Lead

Locomotive.

Communicates with the Locomotive Control System for getting / giving the Operating

Control Signals for running the locomotive and for getting Status signals for showing the

status of the locomotive.

Communicates with the Display for showing the status of all the Locomotives in theformation.

Communicates with the Trail Locomotive which is connected as wired MU to Remote DPCunit through Train Line Wires.

In the locomotive DPC system Interfaces with Loco Control Computer LCC, TFT Display

(MDS 740), Antenna Assembly & Air Flow Sensor (DAFS).

Pushl PusRemot

Radio Link Both Directions

DPC

MDPCC MDPIF

MILS

MDIPMAOP

GP

Relays

Display

Display

Data

Radio

LCC

MCC Driver

Console

AirBrake

System

serial

serial

serial

serial


35/166

- 3 2 -

Block Diagram of DPC System

The Distributed Power System (fitted in ECC#1) Consists of following Cards:-

MDPCC Medha Distributed Power Control Card- For communication withLCC, wireless system for communicating with other DPC systems, reading &

writing of Train Line Relays.

MDPIF Medha Distributed Power Interface Card- For communication with

Display and data logging.

MDIP Medha Digital Input Module- For converting the 74V locomotive control

signals into Isolated low voltage 5V signals.

MILS Medha Digital Output Module- For converting 5V digital signals intoIsolated 74V signals for driving the Locomotive relays and contactors.

MAOP Medha Analog Output Module- For converting the Dynamic Brakingcommand signal (received from lead locomotive through wireless data) to isolated

analog signal of 0 to 74V.

MLCPS Medha Locomotive Computer Power supply- For generating low

level regulated voltages for the modules in the system with input of 74V.

One set of Radio with 5 watt power and Antennahas been fitted at roof top of ECC#1 oneach locomotive. This radio works on the 433.975 MHz frequency.

One no. TFT LCD (MDS 740) Display has fitted in each Driver's Control Stand withDPC system have following specifications-

CONTROL FUNCTION THROUGH DPS:-

Throttle control

Dynamic brake control

Automatic brake control controlled by CCB air brake system of M/s New York Air Brake

Loco independent brake control

Tractive effort limiting Automatic emergency braking

Automatic switching on of flasher light

Sanding

Over ride control

Throttle- Operation of throttle handle (1st to 8th and 8th to 1st) in lead unit is transmitted

and repeated on remote unit.


36/166

- 3 3 -

Dynamic Brake Control-Operation of DB (0% to 100% and 100% to 0%) in lead unit istransmitted and repeated on remote unit.

Auto Brake Control-Operation of Air Brake (A9) in lead unit is repeated in remote unit.

Loco Independent Brake- Operation of Direct Brake (SA9) in lead unit is repeated in

remote unit.

Tractive Effort Limiting- The TE limit will be enabled / disabled on the trailing

locomotive at the same time whenever this feature is enabled / disabled from the lead

locomotive.

Auto Emergency Braking- To avoid run away train automatic penalty brake application

feature is provided in the system for both Lead and Remote Locomotives.

Sanding- When ever sanding switch is operated in the Lead the sanding will be happened

in the remote also.

Over ride function- The Over ride functions available in the system

Running of Remotes in Different Power- This option is useful for running theLead and Remote with different Powers.

DB Cutout- This Option is useful for isolating DB operation from Remote.

Power Disable-This Option is useful for isolating power from Remote.

Brake Pipe Cutout- This option is useful for isolation charging from Remote.

Brake Isolation-This Option is useful for making the Remote to work as Banker.

Direct brake Cutout-This Option is used to isolate the Direct Brake of Remote

from Lead Direct Brake.

ADVANTAGE OF DPS SYSTEM:-

Distributed Locomotives - higher Aggregate HP with lesser peak coupler forces.

Longer Trains imply higher traffic throughput

Continuous Brake Pipe with multiple braking locomotives - Shorter Braking Distances andfaster Brake Pipe Charging.

*****


37/166

Section A6Remote Monitoring &

Management of

locomotive & trains

(REMMLOT) System

- 34 -


38/166

- 3 5 -

REMMLOT System(Remote Monitoring & Management of Locomotive & Trains)

INTRODUCTION

REMMLOT is a network oriented system connecting all Locos with a centralized

Loconet Management System through CDMA, GSM, & GPS network.

Locomotive Train Management System (in short LTMS) provides Data with a single

point access through Internet to all the Railway Staff at remote locations. LTMS is a 24 * 7service provider. Reports like Health status, Fault status, Fault Data Pack, Event recording,

Life Time data and Operational information of the Locomotive are generated by LTMS

software. Reports generated by this system can be used by the managers for decision making,Fault analysis, Trouble shooting or diagnosis, Check performance of locomotive etc., All the

critical information regarding a locomotive is saved in database for quick retrieval. Data

source for LTMS is LRMS (Locomotive Remote Monitoring System). Data retrieval in the

LTMS is asynchronous. The objective of LTMS is to provide data globally and helping theRailway staff in Fault diagnosis and analyze Driver/Train performance, Locomotive

performance. Whenever required, Railway staff can compare the performance of different

locomotives with a single click. Different Data Types information like Health Status, FaultStatus, Event Recorder data are transmitted from LRMS to LTMS at periodical interval of

time. LTMS also provides a feature called mapping which locates locomotive position on

Google map. All the critical information regarding a locomotive is saved in database forquick retrieval. This system can be used to improve operational safety and service the

locomotives better.

Development Stages-

1.) RDSO vide their letter no. SD.DEV.REMMLOT dt. 24.09.07 had requested for

procurement of 100 sets of the REMMLOT system.

2.) A DLW P.O. no. 060880050.09280720 dt. 20.07.2009 was placed on M/s Medha

for 100 nos. REMMLOT as non stock item.

3.) Firm supplied 05 nos. prototype of REMMLOT system as per P.O. which were

fitted on following locomotives;

SN Loco no. Dispatched to Dispatch Dt.

I) WDM3D- 11307 Itarsi / WCR 24.12.09

ii) WDG3A- 13594 Andal / ER 28.12.09

iii) WDM3D- 11310 Itarsi / WCR 30.12.09

iv) WDG3A- 13593 Raipur / SECR 12.01.10

v) WDG3A-13599 NKJ / WCR 18.02.10

4.) As per P.O. clause RDSO issued the Inspection Certificate (IC) for aboveprototype REMMLOT system vide Insp. Certificate no. SD.DEV.REMMLOT.

date 04.03.10.

5.) Firm has supplied the 95 nos. balance quantity of P.O. to DLW.


39/166

- 3 6 -

6.) Railway Board vide their letter no. 2007/M(L)/466/ 19 (84) Vol II dtd.01.12.09has allotted 85 nos. REMMLOT to Zonal Rlys i.e AMV shed- 10 nos., Gy shed-

10 nos., Kazipet- 05 nos, NKJ- 10 nos., VSKP-15 nos., Hubli- 07 nos., KJM- 08

nos., Hawrah-05 nos., Jamalpur- 05 nos., Vatva- 05 nos., Ratlam- 05 nos and 15nos to DLW (ALCO-06 nos & EMD-09 nos.).

7.) As per Railway Board instruction, above 85 nos. of REMMLOT has beendistributed to Zonal Railways, out of which 63 nos have been fitted on

locomotives till Jan-2011. 15 nos have been fitted at DLW (ALCO-06 nos &

EMD-09 nos.).

Configuration of REMMLOT:

REMMLOT consists of LTMS (Loco & Train Management System) and LRMS(Loco Remote Monitoring System).

LTMS is a centralized server connected to the internet via a Static IP addressprovided by Internet Service Provider to communicate with Loco Remote Monitoring

Systems, which are connected with Loco computer to obtain Locomotives health, faultdiagnostics related data and other operational data.

LRMS integrates with Locomotive Computer and GPS receiver to transmit data to LMS

through CDMA and /or GSM communication channels for data transfer that can be used for

various applications.

LocoNet Management System consists of:

1. High end Centralized Server system hardware setup

2. LocoNet Server software

a. LocoNet Communications moduleb. LocoNet Data Acquisition Module

(i) Loco Health Monitoring data

(ii) Loco fault diagnostics related data

(iii) Loco Event Recorder data(iv) Loco Fuel Level Monitoring data

(v) Loco Position and Operational data

c. LocoNet MIS Module as per user requirementd. LocoNet Data Security & Access Control Module

e. LocoNet access control module for secure and controlled access to

the web server

3. LocoNet Management System operations

a. Server maintenance team

b. LMS operations teamc. Loco Technical Experts team


40/166

- 3 7 -

Loco Remote Monitoring System (LRMS)

It is a rugged on-board embedded system mounted in Loco and connected with Locomotive

computer through Serial bus or Parallel Bus. LRMS is a customized system for IndianRailways with interface for Medhas MEP-660 locomotive computer. LRMS obtains in real

time Fault Diagnostic data and other operational data from Loco computer and transfers the

information to LocoNet Management System through available communication network(CDMA and / or GSM).

High Resolution GPS interface hardware to get Loco Position, Latitude and

Longitude information to the LMS Server.

LocoNet Users & Its advantages:

1. Indian Railways top Management:

a.) Effective monitoring system from any corner of the world.b.) Real time MIS information can be sent through mails for each functional

head.

c.) Improves Planning and effective use of Locos.

Indian Railways

Top Management

Loco Shed

Engineers

LocoNet

Management

System

GSM & CDMA Network

Locos are equipped with LocoNet Remote Monitoring System

TCP / IP Protocol

LocoNet Web Server

LocoNet Operations Team

MIS Report Generation

Loco Experts Team

Indian Railways

Operations Team

GPS

TCP / IP Protocol (Web Browser)

Loco Equipment

AMC Vendor

Function Specific AccessFunction Specific Access

Static IP from ISP

TCP / IP Protocol (Web Browser)


41/166

- 3 8 -

d.) Time Study and quality study from top level to make necessaryinfrastructure development plan.

e.) LocoNet Vigilance module generates automatic warning mails and voice

messages to concerned functional heads for necessary action.

2. Loco Shed Engineers:

a.) On line Loco fault diagnosis and loco performance monitoring from Loco shed

engineers desk.

b.) Technical support from Locomotive Maintenance Desk to loco pilot for any

small corrections required during travel, incase of minor equipmentfailures.

c.) Timely service cycle plan and on line report generation for each loco.

d.) Advance Service Spares plan and necessary technical support from equipmentvendors, to reduce loco down time.

e.) On line Emergency service alerts for each service shed functional head.

f.) Centralized technical support team (Loco Experts) for critical problemsolving during service.

3. Operations Team:

a.) Real time Train Position information helps to plan effectively (Note LRMSprovides only Loco Position, Latitude and Longitude data, the required

Mapping software to be integrated).

b.) Loco fault diagnosis information helps operations team to plan alternativesin case of impending loco failures.

c.) Faster clearance of section incase of any minor loco failures through

instant support from Centralised Loco Maintenance Desk.

4. Loco Equipment AMC Vendors:

a.) Remote diagnosis of vendors equipment and monitoring of systemfunctional performance.

b.) Necessary corrective and preventive maintenance plan.

c.) Emergency service team deployment to site location is possible with out waitingfor loco shed engineers call.

d.) Remote access of vendors equipment from vendors design team to asses the

problem and necessary trouble shooting support to their service engineers

e.) Effective planning and monitoring for each sub-system in Loco.

*****


42/166

Section A7

Auxiliary Power Unit

(APU)

- 39 -


43/166

- 4 0 -

Auxiliary Power Unit (APU)

Introduction

RDSO Analysis of the locomotive data has shown that most of the run time of the goods trains isspent IDLING for want of line clear signals on the station & yards for prolonged periods of time.

While a diesel engine is idling at 400 RPM, the diesel engine consumes roughly 25 to 30 litres of

diesel oil per hour.

The diesel locomotive performs two functions while idling at stand still; the compressor maintains

Main Reservoir pressure between 8 to 10 kgs./Sq. Cm and the alternator charges the locomotive

batteries. These two functions do not require much power; however as the full diesel engine runsto cater this requirement, the energy consumed is very large.

Drivers generally avoid shutting down to avoid difficulty in re-starting the engine. To cater to theabove requirement APU system has been developed as per RDSO Spec. MP-0-2400-62-Rev-00-

Sept-09. During APU mode, Locomotive engine will be shutdown & APU engine will start

working which in turn consumes very less fuel i.e. 5 litres.

Development Stages-

RDSO had purchased three nos. APU Unit from M/s Medha/ hyderabad. Out of 03, One

no. fitted by DLW on Loco no. 13583 (WDG3A) dispatched to AMV shed. Aftersatisfactory performance, balance two nos. were fitted on WDG-3A locomotives no. 13599

& 13602 dispatched to NKJ/ WCR and at present above three locomotives are homed at

Diesel loco shed / Gooty.

Further as per RDSO letter no. SD.WDM2.3.6 dt.25.11.2009, procurement of 20 nos. ofAPU for ALCO locomotives was initiated and finally PO has been placed on M/s Medha

/Hydearbad for 20 nos.


44/166

- 4 1 -

Advantages

Reduction in fuel oil consumption. Reduction in lube oil consumption. Reduction in emissions

Extended engine life No dependency on driver.

Automatic changeover.

Function

APU (Auxiliary Power Unit) enable charging of MR pressure & Battery charging even

after shut down of main engine.

APU maintain MR pressure to 8 KG/CM to 10 KG/CM2 after Microprocessor controlsystem shut down the engine.

Maintain charging of Locomotive battery.

Provision to switch over to main engine when crew required.

BLOCK DIAGRAM

`

S.Motors

FPC

AES with APUIn LOCO

MICROPROCESSO

SYSTEM

MainEngine Compr.

Main

MR

PressurA.G.

Loco Bat.

SMC

APU

EngineComp

r.

APU

APAlt

AC

AS

Engine RPM

Loco Speed

10 minutes lapsed

BCP

RH is in neutral

APU Eng. RPM

Wat er level

APU LOP

APU Start

APU Stop


45/166

- 4 2 -

System Hardware and description

Compressor:

Two stage, reciprocating W type, splash lubricated with forced air cooling

system. Discharge pressure of 10.2 Kg/cm2

During loading compressor consumes around 15 HP. Provided with unloader valves to cut in/ cut out the compressor.

Diesel Engine:

25 BHP@1500 RPM, 3 cylinder water cooled with natural aspiration. SFC: 166 gms/ BHP Hour at full load.

Alternator:

3 brush less AC alternator provided with automatic voltage converter to

provide 72 V DC. 2 KW rating at 1500 rpm.

Battery: 12 V for APU engine starting

Compressor directly coupled with Diesel engine through a coupling and the Alternator is directly

coupled to compressor. The Diesel Engine directly drives the compressor and the Alternator. Baby

compressor maintains MR pressure. Alternator along with rectifier generates 72V DC and chargelocomotive batteries while the main engine is shut down. These three sub assemblies are

integrated with associated interconnections to form into APU. APU is interfaced to

microprocessor control system for automatic changeover.

Auto Change over to Fuel Save Mode

Microprocessor control system monitors the loco idling condition; MH in IDLE Loco speed zero BCP > 2.1 Kg/sq.cm.

As soon as loco IDLE conditions are satisfied, Loco microprocessor system starts internal counterand monitors the healthiness of the following parameters for 10 minutes:

AES Enable

Loco engine RPM - 350-400 Loco speed- Zero Self load mode- No MCB1 & 2- ON APU safety devices are in normal position ( Water level, Lube oil

pressure, Fuel level & APU shut down contactor)

If all the above parameters are satisfied for 10 minutes, the Loco microprocessor system checks

the following parameter;


46/166

- 4 3 -

Batt. Chg Current < 10Amp.

MR pressure >= 7.5 kgs./Sq.Cm. EWT sensor is not faulty and EWT > 30 deg. Celsius. EOT sensor is not faulty and EOT > 30 deg. Celsius.

BCP > 2.1 kgs / Sq.Cm. RH in Neutral

When the above conditions are met on the locomotive, Loco microprocessor system display a

decrementing counter and a message system will enter into fuel save mode with in 60 seconds

with intermittent buzzer sounds. This would be final warning message to driver before enteringinto FUEL SAVE mode.

If BC pressure is < 2.0 kgs./Sq.Cm. a message loco brakes are not applied may not enter intofuel save mode displays on screen. Similarly if the reverse handles (RH) is in Forward / Reverse

position, an appropriate message displays and repeat every 10 seconds (configurable) to warn to

driver to set the parameter correct to enable system to go into fuel save mode. In case the driverdoes not want the system to go into fuel save mode, he can keep the RH in working direction.

Loco Microprocessor system continuously monitors the required parameters while APU is

running.

In case of any of these parameter reaches below critical value microprocessor automatically shuts

down the APU engine and cranks the main engine. Status information System returning fromFUEL SAVE mode is displayed to driver and the display returns to previous screen from APU

screen.

CHANGE OVERTO NORMAL MODE WITH DRIVERS REQUEST:

When the driver wants to starts the locomotive or come out of FUEL SAVE mode he can simplythrow the Reverser to required direction. Microprocessor control system senses the status of thereverser handle position and automatically starts the main engine with in 5 to 10 seconds.

Microprocessor confirms normal running of main engine and switches OFF APU.

APU Enable Switch is provided on the circuit breaker panel and is normally kept in ON position

enabling the APU mode by default. Loco Microprocessor continuously monitors the status of this

switch. In case of any fault in the APU, the driver can switch off this AES switch permanently todisable the APU functionality.


47/166

- 4 4 -

FUEL SAVING:

A) Fuel consumption/ hour by diesel engine

of locomotive,when idling at 400 rpm25-30 litre (Approx.)

Say 25 litre

B) Fuel consumption/ hour by APU in APU

mode(275 GS model of M/s Mahendra

make 25 HP small diesel engine used inAPUs fitted on loco no. WDG3A-13583,

13599 & 13602 locomotive and Specific

Fuel Consumption (SFC) at 50% is 189

gms/ bhp

= 25 x 189= 4725 gms

Say 5 litre (Approx.)

C) Fuel Saving per hour per loco = (A) (B)

= 25 - 5= 20 litre (Approx.)

D) Fuel saving per day per loco

( Average idling period of a loco is 9 hrs /

per day calculated on the basis of 18 hrs

idling in two days as monitored by RDSOvide letter no.SD.DEV.APU dtd.

12/13.11.09)

= 20 x 9

= 180 litre (Approx.)

E) Fuel saving per year per loco

( assumed average 300 working days in a

year)

= 180 x 300= 54000 litre (Approx.)

F) Cost of fuel saved ( in Rs.) per loco per

year(@ Rs. 26.93 per litre as per LPR of P.O.

070952130.09128079 dtd. 29.08.09)

= 54000 x 26.93

= 14,54,220/- (Approx.)

Say 14,50, 000/-

(Rs. Fourteen Lakhs Fifty

Thousands only)

G) Cost per unit of the ACES with APU

(as per LPR of P.O. placed by RDSO on

M/s Medha for 03 sets)

Rs. 8,30,000/- + Taxes

(Rs. Eight Lakhs Thirtythousands + Taxes)

*****


48/166

Section A8

Cab Air Conditioning units on

Diesel Electric Locomotives

- 45 -


49/166

- 46 -

Development of Air conditioning units on Diesel Electric locomotives

The development effort for air conditioning of EMD locomotives were started in 2004 withplacement of two developmental purchase orders on M/s Sidwal and M/s Fedders Lloyedto DLW specification no. WDG-4/EL/PS/14. The AC supplied had separate inverters andair conditioning units. 09 units supplied by M/s Sidwal were fitted on locomotives and all

did not perform in field because of various problems and were removed from locomotives.These units were bulky, were protruding inside cab, thereby reducing head space andcausing difficulty in accessing control compartment also.

Further, RB issued directives regarding provisioning of air conditioner on diesel electricloco cabs vide their letter no. 2000/M(L)/466/9 dated 23.07.07.

Considering experiences of earlier units, RDSO prepared a new specification for airconditioning units with compact size and inbuilt inverter. RDSO defined eligibility criteria inclause 16.3 of this specification, which reads as As a pre-qualification criteria, thesuccessful tenderer should have supplied same or similar design of modular ACunit (with built in Inverter) for at least 200 locomotives. The units should have

worked on locomotives satisfactorily for at least 3 years. The tenderer shall submitthe details of AC units supplied for locomotive applications. This clause wasincluded to procure this item form an established source to prove out the concept on theDiesel Electric locomotives.

Model of proposed compact air conditioning unit

A PO no. 091080010.11111254 dated 12.01.2011 for 05 nos. of AC units has beenrecently placed on M/s DPG/USA. A tender for procurement of further 20 nos. of

AC units has opened on 16.12.10, which is under technical evaluation.


50/166

- 47 -

Development of Cab Heaters on Diesel Electric locomotives

The requirement of cab-heating has been a continuous demand from loco pilots fora very long time, though not properly documented. Cab heaters are provided onelectric locomotives since long but they had not been provided on diesel

locomotives because of limitation of power. However, now with increased powerrating of diesel locomotives, the provision of cab heating arrangement has becometechnically feasible.

DLW specification no. WDG4/EL/PS/29 (Rev R0) is prepared by DLW forprocurement of cab heaters. The specification for the cab heater is so designedthat developed product can be used in both EMD and Alco locomotives. It caneasily be retrofitted in existing locomotives in field. This would be very useful forretro fitment purpose. The proposed cab heater is expected to look like:

Proposed cab heater

A developmental proposal for procurement of 20 cab heaters was initiated. GMsanctions the proposal on 17.01.2011 and Non Stock demand has been prepared.

*****


51/166

Section A9

Computer Controlled

Brake system fitted on

ALCO Locomotives

- 48 -


52/166

- 4 9 -

Computer Controlled Brake System fitted in ALCO locomotives.

All the modern locomotives all over the world employ microprocessor controlled brake

system, e.g. CCB (computer controlled brake) system of Knorr Bremse or Fast Brake

System of WABTEC, as it not only lends superior safety features to the locomotive but

also improves maintainability and reliability considerably. The CCB system has the

following numerous benefits:

Higher reliability

Precise and better control of pressures

Self diagnostics

Self test

Enhanced safety through constant monitoring of critical safety functions

Simplification of Pneumatic Components

Due to inherent advantage of CCB, it was decided to use CCB on ALCO locomotives

too. Initially RDSO made a specification no. MP.0.01.00.07 (REV-01), Aug-2007 for

microprocessor controlled air brake system for ALCO locomotives. Now RDSO have

issued a common specification no. MP.0.01.00.20 (REV-02), April 2010 for both EMD

& ALCO locomotives. The CCB system has replaced the conventional panel mounted

brake system with CCB unit and A9 & SA9 valves with brake controller mounted on

control console.

Initially CCB system was fitted on two of the WDG3A locomotives (i.e. 13512 and

13574) of M/s Knorr Bremse India Ltd make. The loco no 13512 was dispatched to KJM

shed of S.W.Railway on 28 Jan 09 and loco no 13574 was dispatched to Raipur shed of

SECR on dated 29 Sep 09.

CCB System Brake Controller


53/166

- 5 0 -

The successful introduction of these systems in locomotives have paved the way for

introduction of CCB on new ALCO locomotives as well as retro fitment on existing

locomotives provided with microprocessor controlled system. Later instructions had been

received from Railway Board to put these systems on 50 more ALCO locomotives (25 at

DLW & 25 at DMW). Based on the instructions, the 15 uncommon items which are

required for fitment of these CCB systems on ALCO locomotives was tendered. The

items have already been received from the suppliers and fitment of the CCB system has

started and fitted in loco nos. 13353, 13354, 13355 and 13356 till date.

Future plan:-

Further, the drawings for fitment of CCB in WDM3D locomotives has been completed

and is being issued to Shop. Fitment of the same is expected to start in the month of

April 2011.

*****

Computer relay Unit

Pneumatic Control Unit


54/166

Section A10

Computer Controlled

Brake-II system fitted on

EMD Locomotives

- 51 -


55/166

- 5 2 -

Modified Computer Controlled Brake System (CCB II)

Vide letter no. SD.Dev.CCB dated 01.12.2009, RDSO advised DLW to upgrade the existing

CCB, to incorporate the improvements made for the direct release version of CCB being used

in USA. The benefits of improved version CCB over the existing version are as under: -

Simplification of solid-state equipment, including the micro-computer, to minimize

number of interface controls.

Improved reliability of providing Redundancy (availability of Back-up modes).

Ease of Maintenance (use of Line Replicable Unit approach).

Rationalization & integration of pneumatic components so as to reduce the number of

components/sub-assemblies.

User-settable parameters & compatibility with related third party equipment,

preferably using an open protocol

Further vide letter no. SD.DEV.CCB dated 22.12.09, RDSO had recommended to Railway

Board that CCB system on EMD locomotives be upgraded to enhance safety and reliability of

locomotives. RDSO had elaborated that in addition to inherent higher reliability and safety

with the improved CCB, there would be immense spin off benefits in the locomotives layout

and equipment, as under: -

i. Since the improved CCB has a smaller envelope, the same would be mounted under the

radiator along side a modified after-cooler pipe. This would release space in the cab

front and a crash structure shall be provided in that space. This crash structure would

ensure that the crew is fully protected in the event of collision apart from limiting the

damage to locomotive itself.

ii. This layout shall also trigger further improvements in the locomotive layout by movingthe ECC#1 and TCC forward and releasing space for inevitable improvements like

provision of a toilet or ACES with APU (Automatic Control of Engine Start with

Auxiliary Power Unit, which results in immense fuel savings).

iii. Retrofitment on ALCo locomotives would be easier as the improved CCB is more

compact.


56/166

- 5 3 -

Based on RDSOs recommendations, Railway Board noted the benefits enumerated by

RDSO for adopting improved version of CCB and directed DLW , vide Railway Boards

letter no. 97/M (L)/466/63 (CCB) dated 01.02.2010, for fitment of 50 sets of improved CCB

on EMD locomotive at the earliest based on the latest RDSO specification no. MP.01.00.24

(Rev 01) Jan 2010)

In view of the anticipated benefits of this improved version CCB and Boards

directives, a PO was placed ( Vide PO no 041013980.10155855 dated 02/12/10) for 50 nos

on M/s Knorr Bremse India Pvt. Ltd./ Faridabad. Supply of the same is yet to commence

from the firm. Thereafter the fitment of the same shall be done on WDG4/WDG5

locomotive.

*****


57/166

Section A11Fabricated Bogie Frames

for EMD Locomotives

- 54 -


58/166

- 55 -

Fabricated bogie frames for EMD Locomotives

With the objective to improve reliability of bogie frame, cost effective anddevelop more sources, RDSO has designed 2 types of Fabricated Versionbogie frames (i.e. Fab-I & Fab-II) in place of presently used Cast Version

bogie frame.

Fabricated bogie frame (Fab-I)

RDSO has introduced fabricated bogie frame (Fab-I) for EMD locomotives (afabricated version of cast frames). Fabricated bogie frame (Fab-I) a lighterversion of cast bogie frame, which has been developed for EMD locomotives,having following advantages over cast bogie frames:

1. Lighter weight (approx-500Kg less weight) in comparison to the Castbogie frame

2. Reduced cost - Cost of Fab-I bogie frame is approximately Rs. 5.4lacks per bogie frame less than cast bogie frame.

3. Reliability - no casting defects

4. More sources are available for development.

On the basis of RDSO drawing no. SK.VL-400 to 406, DLW has placedP.O.s for the fabricated bogie frames (Fab-I) to DLW part no. 17021467on the following firms: -

M/s Anup Malleable/Dhanbad- P.O. no. 040614680.07159606 dated

27.03.07 for 02 nos.

M/s Simplex Engineering/Bhilai- P.O. no. 040614680.07159362 dated25.07.07 for 04 nos.

M/s Ved Sassomaccanica/Kanpur- P.O. no. 040614680.07159566dated 23.08.07 for 04 nos.

Present status-

M/s Simplex has supplied 04 nos. of fabricated bogie frames (Fab-I),02 nos fitted on loco. No. WDG4-12227 dispatched to UBL shed on21.08.2009 and another 02 nos has recently been fitted on WDG4-12355 dispatched to BGKT Shed on 20.12.2010. Performance of thesame is under monitoring by RDSO.

M/s Ved Sassomaccanica/CNB has also developed & supplied 02 nos.fabricated bogie frames (Fab-I) in Jan2011 which are yet to be fitted.

M/s Anup Malleable /Dhanbad has not supplied till date.


59/166

- 56 -

Fabricated bogie frames (Fab-II)

RDSO has introduced fabricated bogie frames (Fab-II) vide their drawing no.SK.VL-507 to 510 for WDP4 (Dual cab) locomotive.

Fabricated bogie frame (Fab-II), a lighter version of Fab-I by using high

tensile plates, has been developed for Dual cab WDP4D locomotives. Fab-IIbogie frame is having following advantages over cast bogie frames:

Lighter weight (approx-1000Kg less weight) in comparison to the Castbogie frame and 500 Kg lesser weight in comparison to Fab-I.

Reduced cost - Cost of Fab-I bogie frame is approximately Rs. 4.8 lacksper bogie frame less than cast bogie frame.

Reliability - no casting defects

More sources are available

On the basis of RDSO drawings, DLW has placed P.O. (no.040880150.09162760 dated 05.03.09) on M/s Ved Sassomaccanica/Kanpurfor 04 nos. of fabricated bogie frames (Fab-II)to DLW part no. 17021492.

Present status-All 04 nos. fabricated bogie frames (Fab-II) has been supplied by the firm.Out of these, 02 nos. have been fitted on WDP4D-40014 (Dual cablocomotive) and has been dispatched to TKD Diesel Shed on 09.10. 2010.

The balance 02 nos. has been fitted on loco no. WDP4D-40026 and

dispatched to TKD Diesel shed on 28.12.2010.

*****


60/166

Section A12

Special supplement

on Design Bulletins

- 57 -


61/166

AN INTRODUCTION TO DESIGN BULLETINS

Every knowledge based organization has considerable tacit

based knowledge resident with the individuals who have

been part of the problem solving process. Unfortunately,

with the change of roles, this knowledge tends to be lost to

the organization.

Design Bulletin aims to capture and embed this tacit

knowledge in the organization knowledge domain. The

bulletin, therefore, not only provides the solution but also

the process. Since the solution may involve action by

multiple agencies, the bulletin provides a structure to the

role of each agency for achieving the solution.

First Design Bulletin was issued on 04.06.2010 and till date

21 bulletins have already been issued. A compilation of all

the bulletins has been included in this issue of Soochna.

The design bulletins have also been posted on DLW web

site for a wider footprint to the solutions. Also since most of

the bulletins are related to the field problems, it will enable

faster dissemination to the customer.

.

- 58 -


62/166

- 5 9 -

INDEX

SN DESIGN

BULLETINNo

Subject Page No.

1 DB/01/2010/01 Power assembly No.7 failures 60 to 62

2 DB/01/2010/02 Procedure for inspection of Air Duct 63 to 65

3 DB/01/2010/03 Turbo failures in EMD engines 66 to 68

4 DB/01/2010/04 Performance of water pumps with indigenousmake impellers on G4 Engines

69 to 70

5 DB/01/2010/05 Crab nut torquing on EMD engines 71 to 73

6 DB/01/2010/07 Inspection procedure for fully machined oil pan 74 to 75

7 DB/01/2010/08 Quality issue in retainer forgings SIFL make 76 to 77

8 DB/02/2011/06 Water pump failures on Alco locomotives 78 to 83

9 DB/01/2011/11 Failures of Accessory drive end gear train. 84 to 88

10 DB/02/2011/12 Power assembly component failures 89 to 91

11 DB/03/2010/01 Issue of Burning of Radiator Cooling Fan

Cables in EMD locos.

92 to 94

12 DB/03/2010/02 Provision of microprocessor driven Speed

Indicator on ALGO locomotives

95 to 99

13 DB/02/2010/01 GR operation problem in EMD locos due to

water

Ingress in TA, ECC 1 & TCC Compartment

100 to 102

14 DB/02/2010/02 Failure of air inlet hose of compressor of EMD

loco

103 to 105

15 DB/02/2010/03(Modified)

Failure of Flexible coupling of Auxiliarygenerator drive shaft on EMD locos

106 to 107

16 DB/02/2010/04 Failure of Cab Seat on EMD locos 108 to 110

17 DB/02/2011/01 Problem of Hosepipe rubbing 111 to 113

18 DB/02/2011/02 Provision of Inspector's Seat in Side Wall

instead of Cab Door in EMD locomotives &provision of inter locking of Inspector seat and

Door opening in ALCO locos.

114 to 116

19 DB/02/2011/03 Failure of HP outlet pipe of compressor 117 to 118

20 DB/03/2011/01 Modification/Rectification in manufacturing

process of Controller ASM Dynamic in EMDlocomotives

119 to 121

21 Cable

Sealing/03/2011/02

Issue of water ingress through DB Cable cutout

in long Hood, in both side (LHS & RHS)

122 to 124


63/166-60

-


64/166- 61-


65/166-62

-


66/166- 63-


67/166-

- 64-


68/166- 65-


69/166- 66 -


70/166- 67 -


71/166-68

-


72/166- 69-


73/166-70

-


74/166- 71-


75/166

- 72-


76/166- 73-


77/166- 74-


78/166

- 75-


79/166- 76-


80/166

- 77-


81/166

- 7 8 -

No. dlw.m.65.262 Date - 21/01/2011

DESIGN BULLETIN

1. Design bulletin no. : DB/02/2011/06

2. Subject : Water pump failures on Alco locomotives

3. Background : Zonal railways have been reporting of failures of water pumpassemblies on Alco locomotives

a) CMPE(D)/NE Rlys L.No.M/ DSL/component/Failure/Pt.III

dated 12.01.2011 b) CMPE(D)/C.Rlys L.No. M.228.RL.WDM2 dtd 11.01.2011

. c ) Sr.DME (DSL) Gonda, Letter No M/GD/DSL/Stat./Failure /2011/01, dated 17.01.11

d) RDSOs IB no. MP.IB.ES.02.12.09, February 2009

4. Failure investigation & suggesting corrective action for eliminating /arresting the

problems of water pump assembly failure.

Details of study/Investigation:

Theoretical analysis to establish adequacy of design in original design of water pump shaft

Original ALCO design of water pump shaft has a taper of inch per foot with a key slot. The

taper provides for easy installation and removal while allowing for a proper and tight fit betweenthe impeller hub and shaft. Advance of the taper sleeve ,with the matching internal taper ,

obtained through lock nut tightening (with 125 ft-lbs) generates an interference between

impeller bore and outer surface of the sleeve. In shaft to hub fits involving interference fit with

key, the torque is transmitted through the keys while the interference fit is to prevent rockingand axial movement of the hub. This prevents fretting which can result in failure of shaft or

impeller. Special care to avoid too tight a fit with keyed hubs is necessary as this can induce

stresses which can cause cracking of the impeller hub.

The torque of 125 ft-lbs on the nut causes the taper sleeve to advance which in turn generates an

interference at the sleeve-impeller hub interface.

T= F d {cos tan+ } + F Do3-Di

3

2 {cos - tan} 3 Do2-Di

2

= pcr1 [ { (1-)/E1} + {(r2 2+ r1 2 )+ }1/E2 ]


82/166

- 7 9 -

(r2 2 - r1 2 )

T = Torque = Interference

Do = Outer dia of washer

Di = inner dia of washer

= coefficient of frictionE = Youngs modulus of elasticity

pc = Contact pressure = Poissons ratioF = Axial thrust causing sleeve advance

d = Thread dia on water pump shaft

2 = included angletan = lead / x d

r2 = impeller hub outer radius

r1 = impeller hub inner bore radius

The torque that can be transmitted by the taper sleeve due to contact pressure generated by

interference = 2 F (ro3 ri

3)

------------------------ 3 (ro2 ri

2) sin

Calculations using above equations indicate that a torque of 125 ft-lb generates a 2659 lbs axialforce on the sleeve . This axial force causes the sleeve to advance and in turn generate

interference at sleeve-hub interface. The theoretical value of interference generated at the

sleeve-impeller hub interface , as calculated by using above equations , with a torque of 125 ft-lbs exerted on the lock nut , works out to around 0.0009 to 0.001. This interference at the

sleeve OD & impeller hub interface will generate a contact pressure of about 9427 psi. This

interference, even with a 70 % contact between the sleeve & shaft, is enough to transmit a

torque of about 230 hp. Here, it is pointed out that hydraulic hp of the pump is 34 hp and the

contact between sleeve & shaft taper should not be less than 70%.

Material of the components having interface :

Taper sleeve Stainless steel

Impeller Cast ironWater pump shaft mild steel

Key mild steel

It is therefore established that the original ALCO design of water pump assembly is adequate

enough to give reliable and designed performance even with 10 impeller. The failures , as

reported by zonal railways, are therefore a result of deviations in the designed parameters for

various components generated during manufacture of these components due to a defectiveprocess & quality control.

Discussion

The type of failures reported by zonal railways in original design water pumps has been of two

types.


83/166

- 8 0 -

(i) Breakage of shafts from the fillet / groove in the vicinity of cross-section change.(ii) Loosening of lock nut resulting in uncoupling / slipping out of impeller from shaft.

Analysis has revealed that the cases of breakage of shafts (i.e. type (i) failures) have beenpredominantly on water pump shafts purchased by the zonal railways from unapproved vendors.

The reason for such failures has been identified as improper machining of groove (notch

formation / tool marks) and inferior quality of steel.

DLW manufactured water pumps have mostly failed due to loosening of lock nut causing

slippage of the impeller out of the shaft. Fretting of the seating surface of the shafts have also

been observed which is indicative of loose coupling of the impeller over the shaft. The reasonsof impeller not getting properly tight fit on the shaft are listed below :

(a) Improper torquing (less than 125 ft-lbs or false torquing due to excessive thread friction orwedge friction)

soochna march2011

Documents