PAS/PAR System Capacity Management Discussion

TomNelligan wrote:But you can't carry that sort of traffic when the speed limit is a lot slower.

I couldn't agree more with both the premise and the conclusion. There has to be a breaking point. It's fine enough to run single track as long as the operator is committed to maintaining speeds. If they aren't my instinct is that you quickly reach the system capacity. As we have noted with the tracks in District 1 north of Bangor a mere upgrade in MoW standards was sufficient to allow a major increase in freight traffic.

Assuming that the same action is taken to the south (TT WEST) that would appear to imply that the days of the winter 10 MPH slow order on PAR District 3 are going to come to an end in the near future.

KEN PATRICK wrote:jaymac. What is 'harmonic rocking'. Last time i ran a car in the HAL consist at Pueblo, we were measuring truck dynamics at various speeds. If there is car 'rocking' , harmonic or not, it would be a function of car suspension not speed. I suspect you made it up as well as the 10-20 thought. I remain convinced that PAR track speeds are subjective and raising same by increments would yield significant operational benefits. Ken Patrick

Seriously?

KEN PATRICK wrote:jaymac. What is 'harmonic rocking'. Last time i ran a car in the HAL consist at Pueblo, we were measuring truck dynamics at various speeds. If there is car 'rocking' , harmonic or not, it would be a function of car suspension not speed. I suspect you made it up as well as the 10-20 thought. I remain convinced that PAR track speeds are subjective and raising same by increments would yield significant operational benefits. Ken Patrick

Ken here is a link to a online copy of BNSF System Special Instructions #2 dated June 1st, 2011. Click down to PDF page 5, right-hand column, point 1(A). It discusses "Harmonic Rocking". The problem is caused by poor maintenance of crosslevel interacting with freight cars having a higher center of gravity, of which loaded hy-cube covered grain hoppers are the worst.
Speed is an issue because at lower speeds the amplitude of each rock is greater. BNSF lists the critical speeds as 13 to 23 mph, while CP uses 12 - 22mph. The problem with lower speeds is that frequently the lower speeds are occurring on lower rated FRA Track Classification. As you go from higher to lower class track the regulations require lower standards for the maintenance of crosslevel.

http://www.blet75.org/SSI.pdf

I think we've now thoroughly proven that harmonic rocking / harmonic roll does actually exist, with legitimate references provided by at least three of us. Case closed?

To see harmonic rocking in action I posted the following link I found on youtube.com. The video is less than 2 minutes long, enjoy the show!

http://www.youtube.com/watch?v=QH8N-KM-znI

I also carry gokeefe's optimism that these track issues will get ironed out come trackwork season. You can't eliminate 30 years of deferred maintenance overnight, and with all the work recently put into D1, PAR probably needs a little catchup for trackwork funding. There has been a big shift in management since Fink 2.0 came into control. I think the new people sitting in Billerica are more driven toward having a functional railroad. We wouldn't have new power, massive track upgrades, new trains, and new customers without them.

While Oil Trains may throw a wrench into crew dispatching, PAR has been pretty good recently in getting trains off CP and onto their railroad. Recently 206 has consistently been arriving on D4 mid-day and forwarded east very soon afterwards. If you wind up in Hoosick Falls between 2 and 4pm you're quite likely to catch it. All I can infer from this, is that 206 arrives in Mechanicville at a fairly consistent time, and PAR is being extra good about recrewing it and moving it across the railroad. I believe the same mindset applies to 22k, with NS breathing down PAR's neck. I can't say the same for EDMO/MOED/RJED/EDRJ, but the eastbounds seems to be running mostly at night, leading me to believe the connecting CP/CSX trains arrive in Mohawk/Rotterdam in the evening. There's also in recent years been a streamlining of freight movements, where traffic now gets rushed across the railroad to Portland, where it is then divided up. There's no more alphabet soup of EDNM/EDRU/EDWA, or cars sitting in Deerfield for days waiting for their respective train.

I think within a decade, Northern New England will have a well run regional railroad. Fink 1.0 is in the past, and Fink 2.0 has a good idea of what he wants to see done.

toolmaker wrote:To see harmonic rocking in action...

Nice video, thanks for posting the link. Brings back memories of the Guilford mainline before the Downeaster upgrade. Whenever a train was leaving one of the numerous 10 MPH slow orders and trying to get back up to a blazing 25 -- often with ailing or underperforming locomotives -- it looked just like that. In fact, I often saw cars rocking even worse than that. Some looked like they would bounce off the tracks at any moment.

Jaymac et al. My knowledge of 'rock& roll' is limited to truck hunting.Properly set constant contact side bearings and truck components matched to the car , i.e. spring configurations etc. eliminate or greatly reduce truck hunting at any speed. The posts offered me the ability to read up on 'Harmonic' .Thank you. I believe ,however, that S-259 trucks eliminate truck hunting and that the new oil cars would prevent hunting , harmonic or otherwise. Perhaps radial trucks would satisfy all hunting due to poor track, stick rail etc. Watching the videos i was struck by the obvious fact that the rocking cars were old. We had a 78" cog on 205 flats carrying 4 5-sided containers each loaded with 25 tons of messy stuff. The cars ran in symbol merchandise trains on both good and marginal track. No problems. I still think PAR can run the oil trains faster. Good posts. Ken Patrick

KEN PATRICK wrote:Jaymac et al. My knowledge of 'rock& roll' is limited to truck hunting.Properly set constant contact side bearings and truck components matched to the car , i.e. spring configurations etc. eliminate or greatly reduce truck hunting at any speed. The posts offered me the ability to read up on 'Harmonic' .Thank you. I believe ,however, that S-259 trucks eliminate truck hunting and that the new oil cars would prevent hunting , harmonic or otherwise. Perhaps radial trucks would satisfy all hunting due to poor track, stick rail etc. Watching the videos i was struck by the obvious fact that the rocking cars were old. We had a 78" cog on 205 flats carrying 4 5-sided containers each loaded with 25 tons of messy stuff. The cars ran in symbol merchandise trains on both good and marginal track. No problems. I still think PAR can run the oil trains faster. Good posts. Ken Patrick

Harmonic Rocking (or Rolling) has little to do with Truck Hunting and everything to do with the Metacentric height of the loaded railcar and its Rolling Moment (or period). When the period of change of Track Crosslevel (difference in height between one rail and the opposite rail are approximately the same as the Rolling Moment there is a significant chance that the Righting Arm will go to a negative number and the freight car will flop on its side. As the speed of the train increases the frequency of Change of Crosslevel will go up.

For basic readers Crosslevel is either positive or negative if the track is canted either left or right, and zero if the rails are perfectly level. Some cant is desirable on curved track, but on straight track zero cant is desirable. On straight track cant will cause the low rail to bear a disproportionate amount of the car weight, assuming the car's load is reasonably balanced, and of course too much cant will cause a freight car to fall over on its side.

Thank you for that fine explanation. I was going to add that it has nothing to do with the actual equipment until I saw that.

The special instruction when I worked for Pan Am was if you were on stick rail and you weren't travelling uphill, and you can't maintain 25 mph you must reduce to 10 mph to prevent a rock-off. I could be incorrect but I think the extra pull on the drawbar when travelling uphill works to negate the harmonic motion. If you notice light power on stick rail you almost always see some harmonic rocking as there is no weight on the trailing locomotives drawbar.

B&M 1227 wrote:You can't eliminate 30 years of deferred maintenance overnight, and with all the work recently put into D1, PAR probably needs a little catchup for trackwork funding. There has been a big shift in management since Fink 2.0 came into control.

I think within a decade, Northern New England will have a well run regional railroad. Fink 1.0 is in the past, and Fink 2.0 has a good idea of what he wants to see done.

Has there been any significant purchases of materials for the upcoming work season, i.e. welded rail, ties and track maintenance equipment? To get the mainline up and running at 25MPH is going to require all of these things to be in place and ready to go come April. Track improvements are going to cost extensive dollars and considerable amount of time to complete the job properly. ST does have a lot of experience with these types of large scale track improvement projects, considering the Portland Division Downeaster and the Pan Am Southern work that was required to get the line running for these new services. The former two projects used outside monies to pay for them verses latter ST paying for these themselves. Norfolk Southern plans to spend $2 billion in 2013 for capital improvements to its network, it should be interesting to see how much work is completed and what the overall improvements are on PAR lines east of CPF-185 come the beginning of next winter.

There has been some plans in the books to drop CWR east of CPF 185 from the spots that aren't between 185 and Danville. CTC will also be extended.

CN9634 wrote:CTC will also be extended.

Hmmmmm.....how far?

gokeefe wrote:

CN9634 wrote:CTC will also be extended.

Hmmmmm.....how far?

Danville is what I've heard.
Will make Maine
dark Keag-NMJ
CTC NMJ-Oakland
Dark Oakland-Davnille
CTC Danville-Out.

I had no idea they had CTC between Oakland and NMJ.