The technical limits being pushed in the Pilbara Region by it's iron ore railways has always been eye catching. For those not familiar. The Pilbara Region in Western Australia holds some of the worlds largest deposits of iron ore. BHP-Billiton, Roy Hill, Rio Tinto and Foretescue Metals Group are the operators in the region. FMG is now running trains with the highest axle load in the world. It has lifted it's axle load from; 40 tonne, to 42 tonne, and now 43.5 tonne. With 45 tonne coming and 50 tonne on the horizon. All this is attainable by an improved lighter truck with beefed up components that's in testing as we speak. Throw in some preventative rail maintenance. A suite of bearing and load detectors with ECP equipped rolling stock and you get a very efficient railroad.
P.S. 43,500KG(43.5 tonne)=95,700lbs. Our current axle load in the US is 71,500lbs. From what I understand UP's Overland Route is rated for 315,000lb GRW (Hopefully Jeff will chime in on this) which breaks down to 78,750lbs. per axle.
How many freeze-thaw cycles does the track structure undergo during the Winter?
Never too old to have a happy childhood!
BaltACD How many freeze-thaw cycles does the track structure undergo during the Winter?
From the link in the OP:
In an environment where temperatures can range from below freezing to more than 40oC, the Fortescue Railway is built to cope with extremes. Structures and earthworks are designed to withstand 1-in-100 year weather events – when the rains come to this arid region, dry river beds quickly become raging torrents which in some cases can be several kilometres wide. Following storms, inspections are carried out using helicopters and road-rail vehicles in order to quickly restore operations.
Much of the time the railroads in the Pilbara are in conditions that are likened to those on Mercury, with the mentioned temperature swings of arid continental regions. You can bet all of the operations in that area, not just Fortescue, need (and have) a first-class track engineering and maintenance operation. Most likely reference and resource will be Peter Clark, who I believe has firsthand experience with some of this.
What is the average percipitation in the area and the normal humidity level?
Cold and dry and cold and wet are two different colds - especially in relation to how the cold affects the ground.
Overmod Much of the time the railroads in the Pilbara are in conditions that are likened to those on Mercury, with the mentioned temperature swings of arid continental regions. You can bet all of the operations in that area, not just Fortescue, need (and have) a first-class track engineering and maintenance operation. Most likely reference and resource will be Peter Clark, who I believe has firsthand experience with some of this.
Pilbara has temps from -275 F to 840 F ?
https://www.space.com/36-mercury-the-suns-closest-planetary-neighbor.html
SD60MAC9500 The technical limits being pushed in the Pilbara Region by it's iron ore railways has always been eye catching. For those not familiar. The Pilbara Region in Western Australia holds some of the worlds largest deposits of Iron Ore. BHP-Billiton, Roy Hill, Rio Tinto and Foretescue Metals Group are the operators in the region. FMG is now running trains with the highest axle load in the world. It has lifted it's axle load from; 40 tonne, to 42 tonne, and now 43.5 tonne. With 45 tonne coming and 50 tonne on the horizon. All this is attainable by an improved lighter truck with beefed up components that's in testing as we speak. Throw in some preventative rail maintenance. A suite of bearing and load detectors with ECP equipped rolling stock and you get a very efficient railroad. P.S. 43,500KG(43.5 tonne)=95,700lbs. Our current axle load in the US is 71,500lbs. From what I understand UP's Overland Route is rated for 315,000lb GRW (Hopefully Jeff will chime in on this) which breaks down to 78,750lbs. per axle.
The technical limits being pushed in the Pilbara Region by it's iron ore railways has always been eye catching. For those not familiar. The Pilbara Region in Western Australia holds some of the worlds largest deposits of Iron Ore. BHP-Billiton, Roy Hill, Rio Tinto and Foretescue Metals Group are the operators in the region. FMG is now running trains with the highest axle load in the world. It has lifted it's axle load from; 40 tonne, to 42 tonne, and now 43.5 tonne. With 45 tonne coming and 50 tonne on the horizon. All this is attainable by an improved lighter truck with beefed up components that's in testing as we speak. Throw in some preventative rail maintenance. A suite of bearing and load detectors with ECP equipped rolling stock and you get a very efficient railroad.
Yes, the original UP side is shown in the time tables for 315,000 tons. The exCNW side isn't in the current UP time tables, only good for 286K. However, some of the last CNW time tables did show the east/west main good for 315K.
I don't know why UP 'downgraded' the exCNW.
Jeff
BaltACD What is the average percipitation in the area and the normal humidity level? Cold and dry and cold and wet are two different colds - especially in relation to how the cold affects the ground.
The Pilbara is very arid being a part of the Australian Outback, and host some pretty intense heat in the summer. Temperatures regulary exceed 90F during most of the year. Here's more on Pilbaras climate.
Thanks Jeff for the update on the weight.
Having been called in by Overmod, I must admit that this is a subject in which I have personal experience, having been employed in rail-wheel interaction studies by BHP from 1975 to 1978 on both BHP and Rio Tinto systems. I have visited every so often, most recently in 2017.
Firstly, the climate: for most of the year it is hot and dry, but in summer there can be cyclones that bring very heavy rain several times during a season. By now most of the watercourses have adequate bridges and culverts but there can be track damage in other areas (and you need to get the water out of the open cut mines.)
FMG have pioneered very effective track inspection using video monitoring from track inspection vehicles with automated artificial intelligence examination of the images. Similar automated inspection of vehicle wheels is carried out at fixed locations on track, including measurement of flange thickness. In a presentation, a photo was shown that had been detected showing a possible crack on the rail surface which turned out to be a large spider which had been run down on the rail head. So manual interpretation is still needed, but the smallest defect can be located.
An interesting change has been the change from G type (7" x 12") bearings to shorter bearings of the same diameter. It was found that at maximum load, the bending in the axle between the roller bearings caused premature failure, but with the same bearings closer together, they ran for longer with no problems.
If I may split hairs, in the metric system, a tonne is a measure of mass and axle loads should be given in units of force, Newtons or in this case kiloNewtons. So we are talking about axle loads of 43.5 x 9.8 = 426 kN.
I measured axle loads in excess of that back in 1978, because BHP's iron ore loader at Mount Whaleback was a 45 degree chute facing the front of the wagon and many wagons had more than 400kN on both axles of the leading truck, and sometimes half that on the trailing truck.
Now we have better control of loading. The generally lower quality ore more common these days is more like dirt than hard rocks and is loaded more evenly.
Another advantage is that all trains are fully equipped with ECP braking, so the longitudinal train forces are reduced, helping coupler life and reducing track damage on falling gradients due to vehicles bunching and "angling" against the rails. The ECP trains can run faster with less risk of train action resulting from brake applications.
So the increase in axle loads is the result of higher track standards ensured by careful inspection, and similar inspection of vehicles combined with the best available braking system reducing in train forces.
An FMG train usually has two locomotives and 250 wagons each of 160 tonnes (352 640 lb) (or more) gross mass. The wagons are about 69 cubic metres capacity each.
The track is 68kg/m rail (136lb/yd) on concrete ties with good quailty ballast. In main line turnouts swing nose frogs are used to minimise impact forces.
All of these ideas are available to US Railroads, although the larger numbers of cars and longer track distances would imply a greater expense in adopting the inpection systems and the ECP braking.
Peter
M636C Having been called in by Overmod, I must admit that this is a subject in which I have personal experience, having been employed in rail-wheel interaction studies by BHP from 1975 to 1978 on both BHP and Rio Tinto systems. I have visited every so often, most recently in 2017. Firstly, the climate: for most of the year it is hot and dry, but in summer there can be cyclones that bring very heavy rain several times during a season. By now most of the watercourses have adequate bridges and culverts but there can be track damage in other areas (and you need to get the water out of the open cut mines.) FMG have pioneered very effective track inspection using video monitoring from track inspection vehicles with automated artificial intelligence examination of the images. Similar automated inspection of vehicle wheels is carried out at fixed locations on track, including measurement of flange thickness. In a presentation, a photo was shown that had been detected showing a possible crack on the rail surface which turned out to be a large spider which had been run down on the rail head. So manual interpretation is still needed, but the smallest defect can be located. An interesting change has been the change from G type (7" x 12") bearings to shorter bearings of the same diameter. It was found that at maximum load, the bending in the axle between the roller bearings caused premature failure, but with the same bearings closer together, they ran for longer with no problems. If I may split hairs, in the metric system, a tonne is a measure of mass and axle loads should be given in units of force, Newtons or in this case kiloNewtons. So we are talking about axle loads of 43.5 x 9.8 = 426 kN. I measured axle loads in excess of that back in 1978, because BHP's iron ore loader at Mount Whaleback was a 45 degree chute facing the front of the wagon and many wagons had more than 400kN on both axles of the leading truck, and sometimes half that on the trailing truck. Now we have better control of loading. The generally lower quality ore more common these days is more like dirt than hard rocks and is loaded more evenly. Another advantage is that all trains are fully equipped with ECP braking, so the longitudinal train forces are reduced, helping coupler life and reducing track damage on falling gradients due to vehicles bunching and "angling" against the rails. The ECP trains can run faster with less risk of train action resulting from brake applications. So the increase in axle loads is the result of higher track standards ensured by careful inspection, and similar inspection of vehicles combined with the best available braking system reducing in train forces. An FMG train usually has two locomotives and 250 wagons each of 160 tonnes (352 640 lb) (or more) gross mass. The wagons are about 69 cubic metres capacity each. The track is 68kg/m rail (136lb/yd) on concrete ties with good quailty ballast. In main line turnouts swing nose frogs are used to minimise impact forces. All of these ideas are available to US Railroads, although the larger numbers of cars and longer track distances would imply a greater expense in adopting the inpection systems and the ECP braking. Peter
Great information, and appreciate the detail. What's your outlook on Roy Hill?
SD60MAC9500 Our current axle load in the US is 71,500lbs. From what I understand UP's Overland Route is rated for 315,000lb GRW (Hopefully Jeff will chime in on this) which breaks down to 78,750lbs. per axle.
Our current axle load in the US is 71,500lbs. From what I understand UP's Overland Route is rated for 315,000lb GRW (Hopefully Jeff will chime in on this) which breaks down to 78,750lbs. per axle.
Most all cars today are built with 110T. trucks for 286k lbs. or 71,500 lbs. axle load but the intermediate trucks on doublestack cars use 125T. trucks with 38" wheels which can handle the 78,750 lbs. axle load and I suspect that is why the UP track rating.
Thanks for your excellent write-up on the Australian RR's, Peter. Here's a link to Timken's Short G bearing:
https://www.timken.com/wp-content/uploads/2020/03/Timken-AP-2-Short-G-bearing_10846.pdf
For those interested in the detail-design improvement in the AP-2 vs. earlier short G bearings, see this paper (which also synopsizes the original Timken IHHA presentation from 2009):
http://railknowledgebank.com/Presto/content/GetDoc.axd?ctID=MTk4MTRjNDUtNWQ0My00OTBmLTllYWUtZWFjM2U2OTE0ZDY3&rID=Mjk1MA==&pID=Nzkx&attchmnt=VHJ1ZQ==&uSesDM=False&rIdx=MzAwOQ==&rCFU=
bogie_engineer SD60MAC9500 Our current axle load in the US is 71,500lbs. From what I understand UP's Overland Route is rated for 315,000lb GRW (Hopefully Jeff will chime in on this) which breaks down to 78,750lbs. per axle. Most all cars today are built with 110T. trucks for 286k lbs. or 71,500 lbs. axle load but the intermediate trucks on doublestack cars use 125T. trucks with 38" wheels which can handle the 78,750 lbs. axle load and I suspect that is why the UP track rating. Thanks for your excellent write-up on the Australian RR's, Peter. Here's a link to Timken's Short G bearing: https://www.timken.com/wp-content/uploads/2020/03/Timken-AP-2-Short-G-bearing_10846.pdf
I would say the same thing regarding the 125-ton trucks. Yet UP is the only C1 with a mainline rated at 315K GRW. Everyone else is still 286K GRW as far as I know. 315K is the future GRW. I wonder if UP just wanted to have it’s main artery the Overland Route ahead of the game.
SD60MAC9500 bogie_engineer SD60MAC9500 Our current axle load in the US is 71,500lbs. From what I understand UP's Overland Route is rated for 315,000lb GRW (Hopefully Jeff will chime in on this) which breaks down to 78,750lbs. per axle. Most all cars today are built with 110T. trucks for 286k lbs. or 71,500 lbs. axle load but the intermediate trucks on doublestack cars use 125T. trucks with 38" wheels which can handle the 78,750 lbs. axle load and I suspect that is why the UP track rating. Thanks for your excellent write-up on the Australian RR's, Peter. Here's a link to Timken's Short G bearing: https://www.timken.com/wp-content/uploads/2020/03/Timken-AP-2-Short-G-bearing_10846.pdf I would same the same thing regarding the 125-ton trucks. Yet UP is the only C1 with a mainline rated at 315K GRW. Everyone else is still 286K GRW as far as I know. 315K is the future GRW. I wonder if UP just wanted to have it’s main artery the Overland Route ahead of the game.
I would same the same thing regarding the 125-ton trucks. Yet UP is the only C1 with a mainline rated at 315K GRW. Everyone else is still 286K GRW as far as I know. 315K is the future GRW. I wonder if UP just wanted to have it’s main artery the Overland Route ahead of the game.
The CNW listed 315K weight limits on some main track segments. I found a 1970 CNW ett showing this. The current UP ett only allows the 286K limit. Why the downgrade, I don't know.
http://wx4.org/to/foam/maps/1_habegger/1970-02-01C%26NW_Iowa_1-JonHabegger.pdf
You have to scroll down. The weight limits were shown in the back of this time table.
Thanks Jeff for the file. I was reading through some of the engine restrictions pretty interesting.
Roy Hill is the most recent of the operating Pilbara Railways. It runs parallel to the BHP and Fortescue lines for about half its length. The ore wagons are basically similar to those of Fortescue. All the latest techniques are in use, for the track: heavy rail, concrete ties, spring rail clips and deep ballast. All locomotives and wagons are fitted with ECP brakes.
Here is a map, including two proposed lines that were not built. Roy Hill is shown as "Hancock" the name of the owner. Roy Hill is the name of a nearby cattle ranch.
The last two lines on the list were not built.
Photographs of the locomotives and rolling stock of the Pilbara railways can be found at
https://pilbararailways.com.au/index2.php
Each system has built on and learnt from those that preceded it.
Late to this thread , anyway .
As Peter mentioned FMG went from 40 to 42 TAL in 2014-15 and so the GVM of their ore cars went from 160 to 168 metric tonnes , 43.5 TAL would make them 174 tonnes .
45 TAL x 4 = 180 gross tonnes and 50TAL = 200 gross tonnes . The latter would make them heavier than their locomotives .
It will be interesting to see how 137 lb/yd rail copes with 45-50 tonne axle loads .
Also something else to consider . For the same 42,000 tonne trains the car numbers could reduce if the GVM was higher . For example 250 x 168T = 42,000T . 242 x 174T = 42,108T and 234 x 180T = 42,120T .
I doubt it would take much longer to load the extra in each ore car , but the significance could be shorter tipping times . FMG I believe uses cars in married pairs and are rotary dumped two at a time . The sooner the empty rake is tipped the sooner the outgoing engines can be attached and set up for departure to the mines .
It could be a while but with 50TAL and 200T gross cars , thats 210 cars instead of 250 for 42,000 tonnes . 40 less cars = 20 less tips and would make a noticeable reduction in train cycle times .
BDAIt will be interesting to see how 137 lb/yd rail copes with 45-50 tonne axle loads.
Time and time again, there have been 'issues' when even slight increases in HAL limits have been made. One effect was excessive plastic deformation of the railhead; another was work-hardening followed by the hardened layer breaking into plates when the softer material beneath deformed; another is brittle cracking of head-hardening. The concern is that these start stress-raising cracks, often vertical in the railhead, that then propagate under the increased cycling load either to spalling or breakage.
A sane company would trade off the increased 'throughput' of the heavier wheel and rail loading against the increased maintenance needed to keep the operation running. In dedicateed service as in the Pilbara, it would at least in theory be possible to operate with the type of regular grinding expressed in the old 'magic wear rate' theory, where you grind to remove the developing railhead deformations before the cracking can propagate, then change the rail regularly as a 'consumable' item and cost. Presumably, sooner or later they'll figure that out for themselves if they haven't already.
The technologies discussed may be available to US railroads, but why would they adopt it?
The Aussie companies likely stay on their own rails, so it's important that those rails are top-notch. Losing a US ROW (as happens due to derailments, weather, etc) simply means taking a detour while the problem is repaired. It might hurt income a little, but not as much as not being able to run at all.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
tree68The Aussie companies likely stay on their own rails, so it's important that those rails are top-notch. Losing a US ROW (as happens due to derailments, weather, etc) simply means taking a detour while the problem is repaired.
If they use CBTC, it would be relatively easy, at least in principle, to schedule the traffic around the required scheduled grinds. Any detection of actual defects in the railhead might be determined by instrumented cars or locomotives, at reasonable cost (note the number of laser geometry car solutions already running cost-effectively here) and maintenance for them scheduled as above using little more than a Brandt unit for the equipment and personnel.
The key is not to pretend that 50-ton loading is just an increment up from 42 ton or whatever. The next "item for attention" -- no surprise to anyone who has been watching the East Palestine show -- is going to be the increased load, especially shock load or point damage/spalling, to the bearing components. I'd expect lots of surprise problems increasingly short of historical MTTF... better have good onboard bearing monitoring in the works.
SD60MAC9500 bogie_engineer SD60MAC9500 Our current axle load in the US is 71,500lbs. From what I understand UP's Overland Route is rated for 315,000lb GRW (Hopefully Jeff will chime in on this) which breaks down to 78,750lbs. per axle. Most all cars today are built with 110T. trucks for 286k lbs. or 71,500 lbs. axle load but the intermediate trucks on doublestack cars use 125T. trucks with 38" wheels which can handle the 78,750 lbs. axle load and I suspect that is why the UP track rating. Thanks for your excellent write-up on the Australian RR's, Peter. Here's a link to Timken's Short G bearing: https://www.timken.com/wp-content/uploads/2020/03/Timken-AP-2-Short-G-bearing_10846.pdf I would say the same thing regarding the 125-ton trucks. Yet UP is the only C1 with a mainline rated at 315K GRW. Everyone else is still 286K GRW as far as I know. 315K is the future GRW. I wonder if UP just wanted to have it’s main artery the Overland Route ahead of the game.
NS has a sizeable amount of 315K rated routes: http://www.nscorp.com/content/nscorp/en/shipping-tools/system-maps-directories-schedules/allowable-gross-weight-map.html
Also, UP has many other corridors, other than the Overland Route, rated at 315K: https://www.uprr.com/software/gis/TNM_Mapbuilder.cfm?app=y&title=Gross%20Weight%20Map&caller=UPFoundation&identify=99&identifya=1&identifyw=350&identifyh=3&identifyll=n&zoom=98&zoombar=L&layers=n&bgs=y&bgssat=y&bgshyb=y&bgsstr=y&bgstop=y&bgsgry=y&bgsdgry=y&bgsnon=y&find=n&server1=tnm&folder1=Public&service1=Public/Weight_Restriction_Overlay&MSVname1=&base=top#
A crucial development in allowing higher axle loads is a better understanding of metal fatigue and how to process steel to reduce fatigue. This led to efforsts to reduce inclusions which were the starting sites for much of the micro-cracks that are the signature of metal fatigue. Wheel and rail grinding also help in minimizing stress concentrations at the wheel-rail interface.
Erik_MagThis led to efforsts to reduce inclusions which were the starting sites for much of the micro-cracks that are the signature of metal fatigue.
I found it useful to look at some of the experience with very hard coatings, many of which are comparatively brittle oxides or nitrides; it is a very common problem to find plastic deformation of the substrate causing enhanced cracking in the hard layer, and tilting of the resulting very hard 'plates' under load is one cause of stress raiser induction. I have seen discussions that this has been observed in the martensitic layer that forms from work-hardening in some rail steels.
Wheel and rail grinding also help in minimizing stress concentrations at the wheel-rail interface.
There are some inherent concerns with current rail grinding: it leaves considerable surface roughness in the as-ground surface, and I have to wonder at the number of small particles of the grinding stones that remain in the surface afterward.
Decades ago, 315,000-lb cars were allowed on most (?) SP main lines, as you see in the MISCELLANEOUS section at the end of Special Instructions for each subdivision. Example
https://wx4.org/to/foam/maps/2-Zukas/08/s/1969-01-01SP_Western_SI3-Zukas.pdf
I'll bet many other RR lines had the same rules then. For all we know they still do?
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