NE SG line, post gauge conversion

 
  MD Chief Commissioner

Location: Canbera
Whats the normal load for the Melbourne - Albury pass trains?
To do 130 kmh on the flat needs 4.7 Hp/tonne.
I would think that a N class would have no problem running at 130 KMh
between Seymour and Albury.
It would struggle south of Seymour due to the 1 in 50 grades, but even the XPT cant
maintain 130 km/h between Seymour and Melbourne, nor would you expect it too.
Back in the days of the old Southern Aurora , it used to 17 cars hauled by a single S or X
and had no problem running at 70 MPH between Seymour and Albury.
Thats only 2.25 HP/tonne.

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  woodford Chief Commissioner

Being a driver at Vline and in the cab committee, I think i know what i'm talking about. As for getting up to speed on this track, it would be quite easy to get to 130K's and maintain it on the long flat straights.
gomer


Many thanks for the reply, its always good to be taken to task by someone the knows what the are doing.

My statements are based on figures produced from a mathematical simulation of the rolling stock and both th Albury and the Ballarrat line. While ist difficult to get such simulations 100 percent accurate, timngs taken from pass's gives me a reasonable level of confidence. IT would be a major advantage to get input from a driver though.
Some results on a level track....


N class loco, traction motor power taken as 2000bhp

Trailing load,5 N series cars 3/4rs loaded, Speed in KPH and distance required to reach that speed in Kilometre,

100kph,1.6k
115kph,2.7k
130kph,4.5k

Trailing load, 5 N series cars 3/4rs loaded plus power van, same deal as above
100kph,2.4k
115kph,3.9k
130kph,6.9k

For this latter example calculated TE at 130kph is 9800lbs, total resistance of the train is calculated as 5500lbs.
So at 130kph we have less than 2 tons of availible TE to accelarate and climb grades, as the train weight is over 400 tons the train cannot maintain speed even on a 1 in 200 grade.

For comparison a loaded 3car VLocity will get up to 130kph in only 2.3 kilometres.

The distances the N with the power car takes to get up to speed effects the short distances between stops the most. North of Seymour the only long distance run is between  Avenel and Euroa. In the simulation substituting a VLocity style vehicle takes around 15 minutes off the time between Seymour and Albury mostly from the ability to get up to 130kph in such a short distance.

The availible TE for an N class at speeds over 115kph is very small compared to the train weight, this cause the train to have difficulty accelarating on any grades.

I am not trying to be a pain in the neck here just trying to understand what would be the best and cheapest way to improve the railways.

woodford
  Duncs Chief Commissioner

Hi Woodford

Can you run your simulator over the XPT train? I would be interested to see how it performs vis a vis the N class loc hauled sets and the V Locities.

I am surprised there appear to be very few long straight (or at least gentle curved) sections of track north of Seymour.

Duncs
  Rodo Chief Commissioner

Location: Southern Riverina
I say Duncs,

From what I can remember, the line north of Seymour consists of long straights with an odd gentle curve here and there. I can only recall slight speed restrictions about Mangalore and Avenel.
  Duncs Chief Commissioner

I say Duncs,

From what I can remember, the line north of Seymour consists of long straights with an odd gentle curve here and there. I can only recall slight speed restrictions about Mangalore and Avenel.
Rodo

Thanks Rodo
  woodford Chief Commissioner

Hi Woodford

Can you run your simulator over the XPT train? I would be interested to see how it performs vis a vis the N class loc hauled sets and the V Locities.

I am surprised there appear to be very few long straight (or at least gentle curved) sections of track north of Seymour.

Duncs
Duncs


A 6 car xpt will have a performance close to a VLocity. The power to weight ratio of the latter is around 10.5bhp/ton, a 6 car xpt 10.0bhp/ton. Although the transmissions in the VLocity are  around 95% effiecent by the way it works not as much power is trasferred to the wheels as in a diesel electric so the power to weight ratios sort of even out.

I have done a time timetable from Seymour to Wagga for both a N class pulling 5 N series cars and a power van and  a VLocity on  the simulator (Note 1) using a top speed of 130kph, the time saved by the VLocity was around 25 minutes. The Vlocity doing considerably better climbing some of the grades in NSW.

Note 1, The simulator is entirely mathematical (ie no graphics at all) contains the both line data for both curves and gradients and all required rolling stock data and outputs train status every second. Inputs are throttle (notched) and brake. One has to drive this stopping at the required stations as well as paying attention to speed limits all the way to Wagga. Station stops are done by stopping the train at the correct exact distance. Doing the program was a real education and one learned a lot about why railways work the way they do.
This experience gave me great admiration for the drivers of these pass's, driving to a timetable thats even remotely tight takes great skill.

woodford
  Duncs Chief Commissioner

Woodford

Thanks fort hat.
  Duncs Chief Commissioner

Woodford

Thanks for that.
  woodford Chief Commissioner

I say Duncs,

From what I can remember, the line north of Seymour consists of long straights with an odd gentle curve here and there. I can only recall slight speed restrictions about Mangalore and Avenel.
Rodo


This is correct,

Slight speed restrictions also through the hills south of Euroa and at Glenrowan. 120kph speed limits exist on around  half a dozen or more unsignaled level crossings, mostly between Euroa and Glenrowan.
  kuldalai Chief Commissioner

The sg North East both tracks are owned by Victoria and leased to ARTC on a long term basis .

The East Line is basically CWR 60kg rail on concrete sleepers . Properly maintained this constitutes Victoria Class - 1 track allowing loco hauled pass at 130 kmh and DMU/XPT at 160kmh .

However the current poor track drainage and quality of ballast and difficulty in maintaining track geometry (level (top) and straightness (correct alignment) ) limit speeds to lower than this . Further to achieve the 130kmh and 160 kmh speeds the issues of signal sighting and adequate lx protection come into the equation . For 160kmh operation Victoria requires TPWS (as fitted on the four RFR corridors) plus boom barriers at all lx where high speed operation is encountered .

With the West Line it is basically older 47kg CWR rail on concrete sleepers . Properly maintained this constitutes Victoria Class - 2 track allowing loco hauled pass at 115 kmh and DMU/XPT at 130 kmh .

However the current poor track drainage and quality of ballast and difficulty in maintaining track geometry (level (top) and straightness (correct alignment) ) limit speeds to lower than this . Further to achieve the 130kmh speed for DMU the issues of signal sighting and adequate lx protection come into the equation . For 130kmh operation Victoria requires boom barriers at all lx where high speed operation is encountered .

In reality the freight traffic largely determines the basic track standard in terms of speed at various maximum tonnage axle loads.
Properly maintained and with adequate drainage and new ballast the best one can realistically expect on the North East is 130 kmh max on the East line & 115 kmh on the West Line for either loco hauled or XPT with adequate lx protection .

The high cost of achieving 130kmh with the costly addition of TPWS would be very hard to justify for the few passenger trains.

With the track in NSW the Single line section from Junee to Albury was relaid with 50kg rail in the 1970's as CWR on wooden sleepers . As such when the XPT arrived it was allowed 160 kmh on this section. The Victorian sg (then only East line) was until the late 1990's 47kg CWR on wooden sleepers . As such Victorian Class 2 track 115kmh max for loco hauled and 130kmh was allowed for XPT .

Since those times both Victoria and NSW have experienced several very serious lx accidents at speed involving derailment of the DMU/XPT trains involving loss of life and major damage to rollingstock .

As such both States now impose a maximum 130kmh for DMU trains on country lines with adequate lx protection . The only exception to this is the four (4) Victorian RFR corridors where DMU are allowed 160kmh with full boom barrier crossing protection and the four corridors are fitted with TPWS .

Hope this clears the question up re speeds and the North East.

Two (2)  footnotes :  The XPT is not called the "slug" for nothing . An XPT accelerates far more slowly than a 6 car V/Locity set .

In the mid  1990's when VLP operated one return Albury trip per weekday with a single Sprinter, (operating on what is now the West line, but as bg),  130kmh was allowed from Seymour to Wangaratta and 120kmh from  Wangaratta to Wodonga.  The lower speed north of Wangaratta  dictated by the fact that was the maximum speed the curves were canted to at that time in that section .
  mikesyd Chief Commissioner

Location: Lurking
I meant to post this a few weeks back but forgot. Driving down to Melbourne on February 13, I noticed that the huge pile of used timber sleepers is still in the paddock on the west side of the line about halfway between Springhurst and Bowser. Google Maps is a bit old in that area, for they don't show up.

Perhaps the owner of the property purchased them (and has done nothing with them), else he is getting a nice chunk of rent from those who do.

From memory, there were a couple more stockpiles further south, I wonder if they still exist.
  Trainplanner Chief Commissioner

Location: Along the Line
Thanks to all for this very informative and most interesting series of posts. Some weeks ago I wrote on the News forum titled Calls for VLocity trains about how services in the north east could be developed going forward. Very lengthy but I'd recommend it to you in view of how this thread has developed. I'm writing from an iPad overseas so I'm not expert in adding links etc but you should be able to locate it. Hopefully as you jump to find it please appreciate it is a longer term perspective and a number of constraints currently existing today would be anticipated to be resolved over time.

In regard to actual performance versus modelling outputs is that in many cases the actual performance in my experience which is by way of direct involvement is often better than the model.  Very shortly after the RFR Geelong Corridor rehabilitation was commissioned I had 2 cab rides in an N set one of 5 cars and the other 5 cars plus a D van. The driver remarked constantly how rapidly the N class was accelerating on the very high standard new track. He commented he was able to throttle back 2 to 3 notches having reached 130km/ hr and that the N was able to maintain speed with a lower throttle setting.  

Similarly in the first weeks of RFR services the morning up Ballarat flagship scheduled to run in 64 minutes ran it twice at 57 minutes and once at 56 minutes.  Also on the Bendigo line climbing grades out of Gisborne the driver had to reduce power on the climb in order to not exceed 130 km/hr.

The relevance to the NE is that we will probably never know what the ultimate potential of the current N sets could be under actual conditions even though the track will at some point enable that operation.  In addition it's not just about reaching 130 km/hr it's also the many kilometres of running that could be run at speeds above 115 km/ hr.

Thanks for the great discussion.
  woodford Chief Commissioner

I meant to post this a few weeks back but forgot. Driving down to Melbourne on February 13, I noticed that the huge pile of used timber sleepers is still in the paddock on the west side of the line about halfway between Springhurst and Bowser. Google Maps is a bit old in that area, for they don't show up.

Perhaps the owner of the property purchased them (and has done nothing with them), else he is getting a nice chunk of rent from those who do.

From memory, there were a couple more stockpiles further south, I wonder if they still exist.
mikesyd

There were 5 stockpiles of removed sleepers, the ones at Boland rd.Boralma (some distance south of Springhurst) and Bower rd Winton are the only ones that remain the others were cut up for fire wood by a machine built for the task. Its possible this particular person did not get (or did not bid) for the disposal contract on the other piles.

The other piles were just north of Avenel, just west of Longwood and well north of the line around 6 ks NE of Violet Town.

woodford
  woodford Chief Commissioner

An (off topic)( comment on mathematical modeling.

The problem with any kind modeling is to try and cater for differences between individual machines. While most machines were built in significant numbers a lot of the larger machines were (and in fact still are) not mass produced, ie the machines are individually built, In aircraft the Vulcan bomber is a good example. In railways steam locos are the classic example as although some were built in very large numbers, they were still all built as individual machines and performed as such.
The problem in modelling massed produced machines such a most diesel electric locomotives is the set up of each machine. In DE loco's the actual power level in the notchs is adjustable as is the rate the locomotive accelarates at. Its almost impossible to allow for such indivdual adjustments so one does the best one can.
In my case I have checked the mathematical modelling against timings taken as a passenger in these machines and I found its fairly close to the real performance particularly for the VLocity.

woodford
  Duncs Chief Commissioner

In my case I have checked the mathematical modelling against timings taken as a passenger in these machines and I found its fairly close to the real performance particularly for the VLocity.

woodford
woodford

I suspect the reason why the VLocity is closer to your modelling than the N sets is because it is a diesel hydraulic, which transmits power through the driving wheels to the track more efficiently than a diesel electric system. Also the VLlocities all use the same standard package of Cummins Diesel and Voith Transmission, which are mass produced to the same standard of production.
  woodford Chief Commissioner

I suspect the reason why the VLocity is closer to your modelling than the N sets is because it is a diesel hydraulic, which transmits power through the driving wheels to the track more efficiently than a diesel electric system. Also the VLlocities all use the same standard package of Cummins Diesel and Voith Transmission, which are mass produced to the same standard of production.
Duncs

Actual the greater accuracy is due to far better data being availible for the engine and transmission for DMU's such as the VLocity and the Sprinter, where as for almost all DE loco's one essentaily has to guess at the losses and power usage in the main altenator, traction motor, auxilary altenator various cooling fans etc. Such power loses can add up to around 500bhp for a loco like the N class on Notch 8. Various sources give the overal efficiency of DE's to between 83 to 92%, probably the later figure is for latter loco's like the GE dash 9's, but one can see there is a fare scoop for variation.

The actual accuracy figures where aprox 1.5 % for the DMU's and around 3 % for the N class, I class the VLocitys as exceptional and the N's figures to be very good, trying to get accurate primary data on the systems for most of these machines is very difficult.
The N class simulation was calibrated against train timings when the loco was known to be on notch 8.

Interestingly the original VLocity simulation was over 8 percent in error, after a lot of work and searching this was finally tracked down to the weight given for the DMU in almost all lists is incorrect, the weight finally used in the sim was given to me by one of its drivers.

woodford
  Duncs Chief Commissioner

Interestingly the original VLocity simulation was over 8 percent in error, after a lot of work and searching this was finally tracked down to the weight given for the DMU in almost all lists is incorrect, the weight finally used in the sim was given to me by one of its drivers.
woodford

That’s very interesting. So how much does a Vlocity actually weigh?
  Bogong Chief Commissioner

Location: Essendon Aerodrome circa 1980
Hi Woodford, your calculations would be interesting, except they are in American units and no one under 50 (possibly even 60) would have any idea what they meant. I'm well into my 40's, so I'm not a kid anymore, but unless I go to the trouble of looking up conversion tables, I will remain confused as to how those outputs compare with other locos and railcars.

As there are no locomotives running that were operational in the days when we used American measurements (except for a few ancient heritage units), it appears you've converted the figures. So if it's not too much bother, could you at least put the conventional measurements in brackets after your calculations so most of us can understand your work?

Thanks. Smile
  duttonbay Minister for Railways

They're not really American units - unless the weight is being measured in US tons, which are different to the rest of the world.  They are British (and once-upon-a-time, Australian) units.
  MD Chief Commissioner

Location: Canbera
You need to be very careful when looking at the specs for DE locomotives.
The power output can be shown as power available for traction , or gross engine power into the
main alternator.
Its important to use the correct one.
I dont know how the N classes are specced, but earlier locos such as the S, X and B classes
all were rated as power available for traction, not gross power into the main alternator.
N class also have a HEP alternator that is driven by an auxiliary diesel engine and doesnt consume
any power from the main engine.
This is differant to an XPT, where the HEP comes from an auxiliary generator driven from the main engine.
Its also worth noting that where the XPT has 2 power cars , only 1 is used to provide the HEP, usually the trailing one.
  woodford Chief Commissioner

Hi Woodford, your calculations would be interesting, except they are in American units and no one under 50 (possibly even 60) would have any idea what they meant. I'm well into my 40's, so I'm not a kid anymore, but unless I go to the trouble of looking up conversion tables, I will remain confused as to how those outputs compare with other locos and railcars.

As there are no locomotives running that were operational in the days when we used American measurements (except for a few ancient heritage units), it appears you've converted the figures. So if it's not too much bother, could you at least put the conventional measurements in brackets after your calculations so most of us can understand your work?

Thanks. Smile
Bogong

I am good at mathematics and in fact use both imperial and metric units, I find though I am better at Visualising problems in certain units so these are used when visualisation is required. There is a time in most projects when visualisation is the best way to proceed, under such circumstances some units are prefered, the exception to this is given below.

In nearly all calculations I use the units that the original data was specified in, the main and one of the few exceptions is power, work and force, then british units are used as I find it easier to visualise these values.

The reason for not converting is that I found one is more likely to produce an error after converting units. A good example is converting linear measurements from fractional inches to metric. Nearly all machines in Australia and Britain made before the 1970's were designed in fractional inches, the converted values are difficult to manage due to them not being precise amongst other reasons. I have very firm views on this comming from long experience.

The above should not be taken that I will never do conversions but for such conversations to be used they need to be proved to be the best way forward.

The original data for the N class locos is in imperial units as is the data for the Cummins QSK19R and the Deutz BF8L513C engines (for the VLocity and Sprinter respectively)

woodford
  woodford Chief Commissioner

That’s very interesting. So how much does a Vlocity actually weigh?
Duncs

Aprox 62 tons per car, this value compares well with weights for Bombardier DMU's built in Europe.
  woodford Chief Commissioner

You need to be very careful when looking at the specs for DE locomotives.
The power output can be shown as power available for traction , or gross engine power into the
main alternator.
Its important to use the correct one.
I dont know how the N classes are specced, but earlier locos such as the S, X and B classes
all were rated as power available for traction, not gross power into the main alternator.
N class also have a HEP alternator that is driven by an auxiliary diesel engine and doesnt consume
any power from the main engine.
This is differant to an XPT, where the HEP comes from an auxiliary generator driven from the main engine.
Its also worth noting that where the XPT has 2 power cars , only 1 is used to provide the HEP, usually the trailing one.
MD


I have a number of maintence manuals from both EMD and GE, including engine maintence manuals these have been good source of original data for most parts of the loco. The engine load tests being particularly valuable.

One has to check all sources of data for use and accuracy once can find a good deal of data if once constantly searchs engineering libraries both real and on the net.

woodford
  Duncs Chief Commissioner

Aprox 62 tons per car, this value compares well with weights for Bombardier DMU's built in Europe.
woodford

Thanks Woodford.
  woodford Chief Commissioner

Large quantities of Ballast are being delivered to Benalla, on the last two runs past the yard two road trucks were unloading both times. A Conveyor is being used to help build the stock pile. The ballast train is also being stabled there.

It appears as if there is still two work groups working on Ballast and Base repair.

woodford

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