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From: Ajai Banarji <banarji@unixg.email

Subject:

Date: 06 Mar 1992 20:41:00 -0500


Elephants (and other animals) on the track
(Note: this is a modified version of a piece written for rec.railroad)

Some time back there was a discussion on the problems of keeping moose off
the tracks in Alaska. But the situation in other places is worse. The Indian
railways have had several derailments (some fatal) involving animals on the
track such as elephants, buffalo and camels.
In 1894 a mail train on the Bombay-Calcutta line was derailed after running
into an elephant near Rourkela. The elephant's skull can be seen in the Railway Museum in New Delhi.
On this occasion no one was killed or injured except for the elephant.
However, in 1869 11 persons were killed when a train derailed after running
into a buffalo near Baroda. Both these accidents took place on the broad
gauge (5'6") which is supposed to be more stable (that's why BART chose this
gauge). But in those days trains were much lighter than they are now.
Even rats have caused accidents-one accident on the North Western Railway was caused when a rat got into a vacuum pipe and affected the brakes.
Anyway, an elephant would have little chance of doing anything to a 50 mph
goods train with a 4500 ton load. Since nowadays most of India's main lines areelectrified at 25 KV AC, the probable result of such a confrontation would be
grilled elephant rather than elephant hash.
You would have to think twice before transporting elephants by open wagons
nowadays, since sooner or later Jumbo would decide to use his trunk to
investigate the overhead wires. Some years ago a trainload of elephants was
sent from Trichur (Kerala) to faraway Delhi to form part of the opening ceremonies of the Asian Games. The train had to take a lengthy detour (via Secunderabad) to avoid the Madras-Vijayawada electrified section. Since most main lines are electrified now, it would probably be impossible to transport elephants over long distances in future.
There is one case on record where an elephant did decide to sample the
overhead wires. Since this was near Bombay (where the traction is a
comparatively mild 1500 V DC), he probably survived without too much harm.
Animals can cause other hazards to railways. Remember the train through
Kenya featured in "Out of Africa"? The line was constructed through lion-
infested jungle in the late 19th century. On several occasions marauding
lines carried away construction workers and brought the project to a halt.
A couple of expert big game hunters were deputed to shoot them. It didn't
work right away, since the lions got into their coach and carried one of them
away.
But if you think that such things happen only in Asia or Africa, you are
mistaken. In 1984 13 persons were killed in a derailment on the Edinburgh-
Glasgow section. Although the railway authorities tried to hush it up, the
actual cause of the accident was a cow on the tracks. The fact that it was
a push-pull operation with the power unit trailing made things worse; had
it been in front it may not have derailed.

From: C. S. Sudarshana Bhat <B536HIND@UTARLVM1.EMAIL

Subject: Trains to Aurangabad

Date: 07 Mar 1992 09:22:00 -0500


Vijay and Ajai have been wondering about trains to Aurangabad. I feel that
the facilities at Aurangabad are not enough to 'house' trains and that might
be the problem that's hindering the authorities form introducing new trains.
In fact, two years ago, Aurangabad station had only three tracks (hope I'm
correct in the terms used) through the station, and not much space, and I don't
think that things have changed all that much since then :-( :-(.

From: Ajai Banarji <banarji@unixg.email

Subject:

Date: 11 Mar 1992 16:05:00 -0500


MORE RAILWAY NEWS

One minor correction to the news which appeared earlier. The budget speech
mentioned that weekly Rajdhani expresses will be introduced between New Delhi
and Secunderabad, and New Delhi and Bangalore in 1992-93. Depending on the
patronage of these trains, similar trains will be introduced from New Delhi
to Madras and New Delhi and Trivandrum.
(Do you really think there is enough demand to justify a full AC train on
these routes?)
Here are a few sample fares before and after the budget:
New Delhi-Bombay: I class goes from Rs 593 to 712, II class goes from 147 to
172
New Delhi-Madras: I class goes from 835 to 1002, II class goes from 185 to 210
Madras-Bangalore: I class goes from 220 to 264, II class goes from 61 to 70

Here are some other recent developments. You already know about the so-called
Bombay-Aurangabad express which runs as a passenger almost all the way.
The Mankhurd-Belapur line is to open up to Vashi in late March.
The New Kurla terminal is being expanded further, though land acquisition
problems have not yet been sorted out. Anyway they now have a couple of
platforms functioning. A few months ago the Varanasi Super Express and a few
locals were originating there. Now the Chhapra and Bhagalpur Expresses and
the Howrah Express (not the Geetanjali) are also running from New Kurla. Many
of the summer specials will also start from there.
One major advantage of the new terminal is that, unlike VT, it can handle
longer trains of 21 coaches.
There is now a long-term plan to expand VT, as the Carnac Bunder goods shed
is being vacated by WR. They will shift their goods operations to Wadi Bunder.

From: S Pai <Pai@CS.email

Subject: Classification of Locos

Date: 16 Mar 1992 16:43:00 -0500


In response to my previous posting, I have received by e-mail the
operational classification (what "WDM-2" means, etc.) of the locos that
is used by IR. However, I'd like to find out some technical details
too, such as the horsepower ratings of the different locos, the design
differences between different types of locos in the same class, etc.
Can anyone help me out here?

Thanks for any information!

-Satish

From: Ajai Banarji <banarji@unixg.email

Subject:

Date: 16 Mar 1992 14:43:00 -0500


Classification of steam locomotives:

These are a few of the steam locos you are likely to encounter in India
today:
WP 4-6-2 BG, found on some passenger trains and few expresses
WG 2-8-2 BG, found on goods trains and some passenger trains
YP 4-6-2 MG, found on passenger trains and expresses
YG 2-8-2 MG, found on goods trains (From a distance YP and YG look the same)
WL 4-6-2 BG, rather rare. Looks a bit like a WG

If you are lucky you may find a few older types like XB (BG, 4-6-2) and
XD (BG, 2-8-2)
Narrow gauge lines have a wide variety of old engines. There are also special
classes like those used on the Ooty line.
If anyone is going to travel in India in the next few years, take a good
look at the steam engines before they disappear.
I have some technical details about horsepower etc for some diesel and
electric locos which I will post shortly.

From: VIJAYB <VIJAYB@PK705VMG.EMAIL

Subject:

Date: 19 Mar 1992 18:47:00 -0500


Ajai writes:
> There is now a long-term plan to expand VT, as the Carnac Bunder good shed
>is being vacated by WR. They will shift their goods operations to Wadi under.

Isn't Carnac Bunder located near Bandra? If so, how would the
shifting of WR operations to Wadi Bunder contribute to the expansion
of Bombay V.T.?

Elec. locos in operation
---------------------------
Here are some of the AC locos. that one is likely to encounter on
electrified sections:
WAP1: High speed, Co-Co type, loco. used for the Rajdhani Exps. and,
possibly, the Lucknow Shatabdi Exp. Hauls the 18 coach Rajdhani
at a max. speed of 120 kmph.
WAP2: Slant-faced, Bo-Bo type, converted WAM2/3 loco. Built by Mitsubishi.
Hauls exp. trains in the Mughal Sarai - Dhanbad - Howrah section.
WAP3: Modified version of the WAP1 w/ fabricated bogies. Hauls the
Bhopal Shatabdi Exp. at a max. speed of 140 kmph.
WAG3: Slant-faced, Bo-Bo type. Hauls goods traffic in the Mughal Sarai
- Howrah, and Igatpuri - Bhusaval sections.
WAG4: Most common among the Bo-Bo type goods locos. Have recently
acquired air-brakes. Can be seen in multiple operation in the
Ghaziabad-Kanpur section (and belonging to the Kanpur loco. shed)
WAG5: "Heavy duty" goods loco. Esp. used to haul freight trains
consisting only of BOX wagons for carrying minerals, such as
those plying on the Kirandul - Visakhapatnam section. Co-Co type.
WAM4: first indigenously built loco. to roll out from CLW (in 1971).
rated at 3600 hp. Has six nose-suspended traction motors attached
to the axles. Uses silicon-diode rectifiers. Perhaps the most proliferant of the elec. locos.
proliferant of the elec. locos hauling both passenger and goods
traffic. Speed potantial -> 115-120 kmph. Co-Co type.
YAM1- Hitachi built loco. for MG traffic. A fleet of ~30 locos. are in
operation in the Madras Egmore - Villupuram section. Bo-Bo type

WCM4 and WCM5 - DC elec. locos. found in the Bombay-Igatpuri and
Bombay-Pune sections. The former was built by Hitachi
and the latter, by CLW. Co-Co type.

WCAM1 - AC/DC locos. catering to traffic on the Bombay Central -
Ahmedabad-Sabarmati section. Co-Co type. Speed potential ->
90-100 kmph. Shares a lot of components with the WAM4.


Regards,
Vijay

From: Vicraj T. Thomas <vic@cs.email

Subject: Re: your mail

Date: 20 Mar 1992 08:25:00 -0500


VIJAYB@pk705vmg.email writes:
>
> Elec. locos in operation
> ---------------------------
> [informative details on Elec. locos]


What are Co-Co and Bo-Bo type locos? Vijay also described the WAP3 as a
"Modified version of the WAP1 w/ fabricated bogies." Does this mean that
Bhopal Shatabdi needs special bogies? Is this because of the high speeds this
train achieves.

< Vic

From: Srinivas Chennupaty <chennu@ccwf.email

Subject: Re: your mail

Date: 20 Mar 1992 10:36:00 -0500


I think Co-c0 and Bo-Bo refer to the type of axles used by the locmotives. I am not sure what they actually mean.
chennu
Srinivas Chennupaty \
Electrical & Computer Engg. \ The moon may be smaller than Earth, but it's
UT Austin \ further away.
chennu@ccwf.email \

From: VIJAYB <VIJAYB@PK705VMG.EMAIL

Subject:

Date: 20 Mar 1992 13:54:00 -0500


Vic writes:
>What are Co-Co and Bo-Bo type locos? Vijay also described the WAP3 as
>"Modified version of the WAP1 w/ fabricated bogies." Does this mean tha
>Bhopal Shatabdi needs special bogies? Is this because of the high spees this
>train achieves.

A Bo-Bo type loco has 4 axles/8 wheels (each of the two bogies has
2 axles/4 wheels). A Co-Co type loco. has 6 axles/12 wheels.
I am not sure what fabricated bogies mean, but I would assume that it
has something to do with the high speed at which the Bhopal Shatabdi Exp
is booked to run. The WAP-3 is rated at 4000 hp., and has innovative
features such as auxiliary warning system, flasher lights and electric
alarm chain apparatus.

Vijay

From: Sampath Kumar <sampath@unssun.email

Subject: terminal at vikhroli

Date: 20 Mar 1992 09:25:00 -0500


There was a plan in 1987 to expand Vikhroli station on central railway, Bombay
and convert it into a terminal to ease the traffic at Dadar and VT. Anyone has got any idea about the status of this plan?

Sampath

From: Ajai Banarji <banarji@unixg.email

Subject:

Date: 21 Mar 1992 14:50:00 -0500


More about diesel locos

(Vijay, please fill in any details missing)

On broad gauge you are likely to see:

WDM2: The most common type, used for both gooods and passenger.
WDM4: Looks broadly the same as WDM2, but more powerful. Not used on all zones;
I never saw them on Southern Railway. These were used for the Rajdhani
in pre-electrification days.
There is a variety of WDM2 which has a remodelled end to give
a clear view to the driver; it looks a bit like Amtrak's F-40. I'm
not sure if this has a separate code.
WDS6: Generally used for shunting, but also used for local passenger trains.
There are a few older types (which look like the US diesels of the
1950s). I saw these on the Gomoh-Garwa Road chord in the late 70s;
they may have disappeared by now.

On metre gauge:

YDM4A: The standard type used for goods and passenger.

On narrow gauge:

ZDM3: Multi-purpose; used even on hill railways like Kalka-Shimla.

There is also a diesel used on the Neral-Matheran line. This must be
different as this line is of 2'0" instead of the usual 2'6"

From: Ajai Banarji <banarji@unixg.email

Subject:

Date: 26 Mar 1992 19:14:00 -0500


A PROPOSAL FOR IRFCA-CREATING A DATA BANK ON LOCOMOTIVES

Here is something constructive we can do. As of today there is no single
book which gives particulars and pictures of all the locomotives in use in
India today. Apparently Vijay has the data for most electric locos; others like myself have bits and pieces of information.
In case we are having a convention in the near future, it may be a worthwhile
idea to prepare a sort of data bank of pictures and other details of all the
locomotives IR uses today. I'm sure most of you will find this useful.

From: A. N. Shekar <mwk!shekar@Menudo.email

Subject: An Old Accident Report

Date: 30 Mar 1992 13:07:00 -0500


[ This is an insider's account of a tragic train accident that occurred in
the mid '70s. I have stated the facts as accurately as I can recall them,
and corrections/additions/questions/insights are naturally welcome. ]


The 204 Down Mahalakshmi Express runs from Miraj to Bangalore City [1] daily,
pulling out of the dusty Miraj station at 6:10 am. It is hauled by a
YDM-4A diesel locomotive and has 11 or 12 coaches. It is not an especially
fast train by today's standards, but for a metre gauge route limited to
75 kph, it did pretty well, averaging almost exactly 50 kph in covering the
749 km in 15 hrs. (In fact, save for the Madras-Madurai Vaigai Exp. I did
not know of any other faster metre gauge trains in those days, but surely
there were some...)

One summer morning (I was home for the holidays, so it must have been summer),
I was lounging about at home after my Dad had left for work when the dreaded
tell-tale accident sirens began wailing in the "yards" off in the distance.
If you didn't know, the sirens were a call-to-duty to emergency salvage and
construction crews to man a breakdown-special train that would head to an
accident scene.

My Dad did not return for dinner at his customary hour in the early evening,
and when he did show up, he was haggard and bleary-eyed; he cursed his luck,
because he had been at the controls (he was a train controller) only five
minutes when word was received that the Mahalakshmi Express had jumped the
rails and that there were fatalities. He would likely have to appear before
an investigative panel and face other unpleasant formalities!

( As it turned out, my Dad was assigned an investigative role himself in
the affair, and most of my info comes from there.)

The ill-fated train, with Rashid Khan [2] at the helm, was over 2 hours late
getting out of Miraj, and in the 160 minute run to Belgaum, had not managed
to make up any time. Negotiating the curves in the hilly jungles near Khanapur
at high speed, the coupling between the loco and the No. 1 bogie broke; the
vacuum hose fittings used for the braking system ruptured, and the brakes on
the lead coaches of the train locked up. As the engine broke loose and hurtled
forward, the momentum of the rear coaches, the sudden braking, the high speed,
and the curvature of the track caused the coaches to derail. Several of them
capsized and were crushed into the hillside; when the body count was complete,
22 people were dead, and scores more were injured.

My Dad had known Rashid Khan for several years, as a driver who could be
relied upon to keep his trains punctual. On many occasions, including once
the previous month, he had been commended for bringing in on-time or near-
schedule, trains that were hopelessly late. This was usually in the form of
an on-the-spot cash award from a railway operations officer, on the station
platform, even as the driver alighted from his locomotive after his speedy
run. This built up a reputation for such drivers, and a fatal accident such
as this one, was one of the very rare occasions when the negative aspect of
speeding (an understatement!) ever came up. In fact, no one really wondered
about how a late train could be made to arrive on time, as if it were
easily attributable to some form of skill and magic on the driver's part.

There was instant speculation, therefore, that Khan had been leaning on the
throttle a little too heavily this time. Another really strange thing had
happened. When his engine broke loose, Khan brought it to a stop within about
a mile, but instead of backing up to the accident site and helping with the
rescue effort (which was standard operating procedure, I believe), he chose
to drive forward to the next station about 8 km away - and he took a really
long time doing it.

After rescue teams and investigators had begun work, the tachograph on the
locomotive was impounded. I'm not sure what type of speed recording devices,
if any, are present on other types of locomotives, but on the YDM-4 and 4A
locos, the tachograph records speed on a circular piece of paper with a 12
hour time scale on the circumference and a speed scale on the radius. At the
start of a trip, the driver is supposed to position a new sheet into the
tachograph so the needle pointed to the correct time. A circular time-velocity
plot is obtained, and this is supposed to be turned in to the home loco shed
for their permanent records at the end of each trip. Some drivers didn't
follow this practice, but Rashid Khan did appear to have one in his loco
on that fateful day.

As part of the inquiry, my dad got the job of judging the speed at which
Rashid Khan was driving when the accident happened. A simple matter, if you
know how to read a graph...but a cursory examination showed that the duration
of the trip on the graph was about 7 hours, whereas Khan had been on the
road only for about three. Worse, the graph showed zero velocity for some
periods of time (stops enroute) that could not have happened on this trip at
all. Integrating velocity over time, it was obvious that Mr. Khan, perhaps
nervous about his culpability in the affair, and with insufficient knowledge
of how a tachograph worked, had popped in a sheet from a previous trip,
hoping that it would deflect blame from him. (He either had some old sheets
lying about inside the engine or had some in his baggage. It was also
possible that a new sheet was never inserted at the start of the trip, but
Khan insisted to the inquiry board during questioning, that he had, in fact,
inserted a new sheet into the machine at Miraj.

(As it turned out, the distances and times on the tachograph matched what the
Hubli-Guntakal Vijaynagar Express would have generated on a typical run.)

Khan was dismissed for falsifying information and impeding the investigation,
and he was only months away from a peaceful retirement and a generous pension.
For lack of evidence, it could not be proven that he was speeding. But as it
turned out, he need not have bothered lying about the tachograph.

In analyzing the working time-tables for the section where the accident
occurred, it was concluded (by numerical integration) that with
the speed limits in effect over various sections, the halts enroute,
and the time required for acceleration and deceleration, the Mahalakshmi
Express could not _possibly_ ever have been on schedule. A driver would
have had to go above the speed limits to be on schedule, even if he started
out on time. This fact could have gotten Rashid Khan off the hook if he had
not tinkered with the evidence.

Rajendran [3], a colleague of my dad who assisted in the investigation, and
who, coincidentally was responsible for creating the working time-tables,
had made an inadvertant arithmetic error in his times, and no one had ever
caught the fact despite reviews and years of operation with those times.
Rajendran suffered a minor reprimand for his oversight - minor, because
several higher-ups who should have double checked, had ok'd the time-tables.
(Also, there was some slight bitterness between our families because we had
been close friends until then, and my dad's role in the investigation irked
Rajendran's wife. This has since been forgotten and all is well again!)

Other experienced drivers privately conceded that they'd touched 100 kph on
some straight sections of track, and had routinely done 90 kph on 65 and 75 kph
sections. Their guess was that Khan was doing about 90 when the crash
occurred, and it was his "bad luck" that this dreadful thing happened.

As to the actual cause of the accident, it was concluded that a poorly
welded piece in the coupling had developed a crack that had been overlooked
in routine inspections, and metallurgical analysis showed stress failure in
the salvaged coupling pieces. I don't know if any heads rolled for that one...
A lot of verbiage about the need for more thorough inspections of rolling
stock and adequate supervision of repairs, was inserted into the report from
the investigation.

Personally, I felt that it was ridiculous, even in a fail-safe brake design,
to have the brakes applied that suddenly and uncontrollably to a fast moving
train due to vacuum failure, but my dad claimed that that was the way it was.

The whole business of on-the-spot cash awards was highlighted, and the
active role of the railway management in encouraging speeding, were also
discussed in the investigation. The practice has been discontinued since,
much to the chagrin of the loco jockeys.

The Mahalakshmi was slowed down by a whole hour on its Miraj-Bangalore City
run after the accident. Beyond hitting an occasional cow on the tracks, or a
bullock-cart at an unmanned crossing, the train hasn't had any further
mishaps in the years since.


()()()()()()()()


Footnote: [1] Since about 1989 the train runs to Mangalore instead of
to Bangalore City.
[2] Not his real name.
[3] Not his real name either, don't want his wife getting all
worked up again.

()()()()()()()()


A. N. Shekar (shekar@mwk.email

From: VIJAYB <VIJAYB@PK705VMG.EMAIL

Subject: More about diesel locos.

Date: 31 Mar 1992 18:23:00 -0500


Here's some info. from "Advanced Rly. Operation - Da Costa"

The first heavy duty diesel loco. on the Indian Railways was brought in 1957-58 to be used in the coal-steel belt to fill in the gap till electrification
of the lines was completed. These are diesel-electric ALCO locos. and are known as WDM1. (these are probably the locos which Ajai came across in the
Gomoh - Garwa Rd. section)
Wheel arrangement CoCo
Horsepower 1950/1800
Max. speed 105 kmph.
Driving Cab Only at one end
These locos. are homed at Gaya (40) and at Bondamunda (60) in 1963. The locos.
at Gaya were transferred to Patratu (Karanpura Coalfields). Those on the
S.E. railway are distributed between Visakhapatnam and Bondamunda sheds.
The above locos were not powerful enough to haul heavy trains unless double-
headed and had to be turned at the terminals. More powerful locos. were
then arranged:-

2600/2400 hp. WDM2 Diesel Electric (ALCO)
2600 hp. WDM4 Diesel Electric (GM)
Wheel arrangement CoCo
Max. speed 120 kmph
Driving Cab Rather on one side, with long and short hoods in front, with two driving controls so that no
turning is necessary
Loco brakes Compressed air brake, hand brake and rheostatic
dynamic brake
(Is the hand brake operated in conjuction with the vacuum brakes
present on the wagons/coaches? How does a dynamic brake operate?)
Couplings Transition-type Center Buffer coupler
Hauling capacity:-
Goods Passenger
WDM2 Four Wheelers BOX Speed
Above 2600 tonnes Above 3600t Upto 60 kmph. 790 tonnes at 100 kmph.

WDM4 Above 2600t Above 3600t Upto 60 kmph. 855 tonnes at 100 kmph.

The main sheds having these locos are Mughal Sarai, Visakhapatnam, Ratlam,
Itarsi, Erode, Tughlakabad, Andal, Gooty, Howrah, Katni, Bondamunda, Ludhiana, and Kazipet. (how about Jhansi?)


Diesel locos. for MG main lines are YDM3-5. These are about 1400 hp. DLW
makes YDM4 type locos (ALCO make). These are homed at Guntakal, Abu Road,
Siliguri and Bhagat-Ki-Kothi (Jodhpur) sheds.
YDM4:- 1380/1245 hp, 96 kmph. max. speed
Hauling capacity: goods (4 wheelers) above 2000t at 40 kmph.
passenger above 605t at 80 kmph.


Regards,
Vijay

From: aravind <aravind@vax135.email

Subject:

Date: 01 Apr 1992 08:29:00 -0500


I would like to thank the person who posted the account of the
Mahalakshmi Exp. accident and its investigation. It was
informative, educational, and a very good read. Thanks once
again ...

aravind

PS Vijay, you neglected to include the MG diesel shed at Golden Rock,
outside Tiruchi ... it's been in operation for 15 years, I think ..

From: A. N. Shekar <mwk!shekar@Menudo.email

Subject: Re: Dynamic braking

Date: 01 Apr 1992 07:36:00 -0500


Vijay ("pk705vmg.vnet.ibm.com!VIJAYB") writes in "More about
diesel locos":

> How does a dynamic brake operate?

In a generic sense, dynamic braking is achieved by letting the
momentum of the train drive a generator in the engine through
the wheels and gearing, and letting the resulting opposing torque
in the generator slow the engine down.

In electric locomotives, the generator is really just the motor
being driven by mechanical power after electrical power to it is
disconnected. In some implementations, electricity generated
during dynamic braking is used to charge on-board batteries, in
some others it is fed back to the grid, and in other cases,
it is just exhausted as heat through a variable electrical
resistance (a rheostat.)

In diesel electric locos, the dynamic braking is activated by
decoupling the mechanical drive from the diesel combustion
engine to the motor-generator set. I am not certain if the
mechanical coupling between the motor and generator is also
removed to let the motor function as a generator driven by the
engine's momentum, or (unlikely) wheel/gearing power is somehow
routed to the real generator with the motor disconnected. In any
event, the generated electricity is burned off in a rheostatic
device.

Dynamic braking saves wear and tear on brake pads and is a lot
smoother than mechanical braking. But it only slows the engine
down, while the rest of the train still tends to roll. Naturally,
it is not used in emergency or sudden stops, unless it is designed
to act in a supplementary fashion to mechanical brakes. In some
rakes with with multiple drive units (such as in electric locals
on the Madras-Arakkonam section), dynamic braking is a bit more
effective because more than one piece of rolling stock is providing
braking action.

A. N. Shekar (shekar@mwk.email

From: Jishnu Mukerji <jis@usl.email

Subject: Re: More about diesel locos.

Date: 01 Apr 1992 08:50:00 -0500


Excerpts from personal.IRFCA: 31-Mar-92 More about diesel locos.
VIJAYB@PK705VMG.EMAIL (2436)

> 2600/2400 hp. WDM2 Diesel Electric (ALCO)
> 2600 hp. WDM4 Diesel Electric (GM)
> Wheel arrangement CoCo
> Max. speed 120 kmph
> Driving Cab Rather on one side, with long and short hoods in
> front, with two driving controls so that no
> turning is necessary
> Loco brakes Compressed air brake, hand brake and rheostatic
> dynamic brake
> (Is the hand brake operated in conjuction with the vacuum brakes
> present on the wagons/coaches? How does a dynamic brake operate?)
> Couplings Transition-type Center Buffer coupler
> Hauling capacity:-
> Goods Passenger
> WDM2 Four Wheelers BOX Speed
> Above 2600 tonnes Above 3600t Upto 60 kmph. 790 tonnes at 100 kmph.

> WDM4 Above 2600t Above 3600t Upto 60 kmph. 855 tonnes at 100 kmph.

Some more info on the lineage of these locomotives:

The WDM2 design is derived from the ALCO Century series design. The
original design and patents are now owned by Bombardier, who acquired
Montreal Locomotive Works, which had acquired rights to ALCO stuff when
ALCO went out of business.

The WDM4 design is derived from the very popular GM EMD GP (Geep)
series. All of the WDM4 units on IR were manufactured at EMD's LeGrange
works and shipped to India in semi-knocked down condition. I was under
the impression that all WDM-4s were homed at Mughal Sarai, but I may be
wrong. It has been a long time since I tracked these sorts of info.
A couple of WDM-4s received higher gear ratio bogies for operation on
the Howrah Rajdhani Express, and associated trial runs.

As for brakes, hand brakes are applied only when the loco is standing
still on a slope, mainly to make sure that it does not roll away.
Dynamic braking consists of using the traction motors as generators and
feeding the generated current into banks of resitences to convert the
energy into heat that is radiated away. This kind of braking is very
effective in holding a train at steady speed while going down a slope.
It also reduces the wear and tear on brake shoes.

Any news on new developments in the area of Diesel Electrics on IR? The
trend these days in the USA seems to be to go for ~4000HP locos. This is
being done even on retro-fits, which suggests that the basic WDM2 design
can be upgraded by using a more powerful prime-mover, and new
elevtricals. Any work going on at all at RDSO on using AC transmission
and traction motors? That seems to be another trend in the world.

Jishnu Mukerji
jis@usl.email

From: Jishnu Mukerji <jis@usl.email

Subject: Re: Dynamic braking

Date: 01 Apr 1992 15:37:00 -0500


Excerpts from personal.IRFCA: 1-Apr-92 Re: Dynamic braking "A. N.
Shekar"@Menudo.email (1819)

> In diesel electric locos, the dynamic braking is activated by
> decoupling the mechanical drive from the diesel combustion
> engine to the motor-generator set. I am not certain if the
> mechanical coupling between the motor and generator is also
> removed to let the motor function as a generator driven by the
> engine's momentum, or (unlikely) wheel/gearing power is somehow
> routed to the real generator with the motor disconnected. In any
> event, the generated electricity is burned off in a rheostatic
> device.


In diesel electric engines (e.g. WDM-2 and WDM-4 class locos), there is
no mechanical connection between the diesel prime mover and the wheels.
The diesel engine is coupled with an electric generator. Electricity
generated by this generator is used to power traction motors attached to
the wheels. These motors drive the wheels. These motors are usually
suspended in the wheel bogie, and are mechanically coupled to the axles
to drive the wheels.

Activation of dynamic braking essentially consists of disconnecting the
the power feed from the generator to the traction motors and then
connecting the traction motors across a bank of resistors (well it is
slightly more complicated than that but that is the gist of what is
done). In this configuration the traction motors act as generators
converting mechanical energy of the trains motion into electrical
energy, which is dissipated in the form of heat through the resistor
banks, thus slowing the train down. The diesel engine and generator is
meanwhile off line and idling along (except on Amtrak F40s, where the
diesel engine continues to run a 7th notch generating hotel power for
the train).

So the bottom line is that the prime mover generator is not involved in
dynamic braking at all. There really is no meaningful way of involving
it. (If only we had reversible diesel engines that could be run
backwards to generate diesel fuel from mechanical energy!:-))


Jishnu Mukerji,
jis@usl.email
+1 908 522 5024,
UNIX System Laboratories Inc.*
(*A subsidiary of AT&T)
SF 1-346, 190 River Rd.,
Summit NJ 07901

From: A. N. Shekar <mwk!shekar@Menudo.email

Subject: Re: Dynamic braking

Date: 02 Apr 1992 07:12:00 -0500


In my post regarding dynamic braking, I made several errors of fact and
oversight ("mechanical coupling" when I meant to say electrical, etc.);
thanks to Jishnu Mukerji for providing corrections and a more insightful
explanation.

A. N. Shekar (shekar@mwk.email

From: VIJAYB <VIJAYB@PK705VMG.EMAIL

Subject:

Date: 02 Apr 1992 10:17:00 -0500


Thanks, Jishnu and Shekar, for providing useful info. about dynamic
braking in locos.

>Any news on new developments in the area of Diesel Electrics on IR? The
>trend these days in the USA seems to be to go for ~4000HP locos. This i

The "Advanced Rly. Operation" book mentions that IR plans to import 50 diesel
locos., each with about 4000 hp. Global tenders for these locos and
about 1,800 bogies have been floated. The idea is to import bogies from
various countries and then carry out tests to identify the ones best
suited for Indian requirements and manufacture. (This news could very
well be outdated implying that such locos. might already been imported
and are being tested out right now)

For the MG system, higher hp (2000 hp) YDM6 locos have been designed
and prototypes are planned for manufacture. Higher hp diesel-elec.
locos., to be manufactured with AC drives, are also being looked into.

As far as elec. locos. are concerned, I believe about 10-15 6000 hp
locos have been imported from Japan (made by Hitachi) and trial runs
are being made in the Kirandul-Kottavasala-Visakhapatnam section.
You may recall that the existing WAP1, WAP3 and WAG5 locos. are rated at
>= 4000 hp.


Here are some comments on Shekar's informative article on the
Mahalaxmi exp. disaster:
>speeding (an understatement!) ever came up. In fact, no one really wondred
>about how a late train could be made to arrive on time, as if it were
>easily attributable to some form of skill and magic on the driver's par.

The max. speed at which a train is booked to run on a particular section
(i.e. adhering to the time-table schedules) is typically 10-12% lower
than the maximum permissible speed on that section. This provides
some make-up time for trains running late. In addition, a certain
amount of make-up time may be explicitly alloted at the end of major
sections. e.g. if you consider the Bombay-Bhusaval section, all Dn. trains
are given about 20-25 mts. extra time in the Bhadli-Bhusaval stretch
(Bhadli is one stn. before Bhusaval).


>(As it turned out, the distances and times on the tachograph matched wht the
>Hubli-Guntakal Vijaynagar Express would have generated on a typical run)

Confirms that the loco. used to haul the Mahalaxmi exp. on that
fateful day, belonged to the Hubli shed. Do all trains change locos.
at Hubli?


Regards,
Vijay

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