-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
QUOTE: Originally posted by oltmannd QUOTE: Originally posted by futuremodal QUOTE: Originally posted by oltmannd QUOTE: Originally posted by greyhounds Slack is not a problem with putting RoadRailers on the back of an Intermodal train. Niether is positioning them on the rear of a train. If you're worried about slack, just use distributed power. Instead of three locos on the head of the train, put two up front and one in back. Make your pickup behind the third unit. The "Slack Problem", if there ever was on in an articulated IM train, is solved. The "rear only" thing can be solved with some planning. Here B an example. Denver is an inbound city. Equipment goes empty there and there aren't any loads outbound for the equipment. BNSF has to drag the empties back to Chicago. What a waste of diesel fuel. But, there are large meat plants on line at Ft. Morgan, CO and Grand Island, NE. All the outbound fresh beef goes by truck. Just put the RoadRailers (which took loads in to Denver) on the back of the IM train from Denver to Chicago. Make a set out and pick up at Ft. Morgan and Grand Island. And handle the loads on the rear. Ain't no big thing. Haul the freight and send 'em a bill. Yes, you're going to have to have the train do work at these two points. It's not like a new thing. Trains have done work at Ft. Morgan and Grand Island for over 100 years. The alternative is to continue to move empty equipment all the way out of Denver, with zero revenue to cover the costs. Hanging them on the rear will limit flexibility, but the rewards (revenue) will more than offset the costs of the limits. The slack problem, if it exists, can be solved. Ken Understand how dist. power can help and engineer control slack. But, it doesn't prevent run in or run out if not used properly. If you put 2000' of RR behind 8000' of conventional IM - distributed power or not, you can still have the slack run in/out and generate some high forces. Ideally, you want the RR units up front, followed by the DPU, then the rest of the consist. That would be worse. RRs are only good for 400,000# buff. You can't count on a DPU to keep buff forces from the RRs if slack runs in.
QUOTE: Originally posted by futuremodal QUOTE: Originally posted by oltmannd QUOTE: Originally posted by greyhounds Slack is not a problem with putting RoadRailers on the back of an Intermodal train. Niether is positioning them on the rear of a train. If you're worried about slack, just use distributed power. Instead of three locos on the head of the train, put two up front and one in back. Make your pickup behind the third unit. The "Slack Problem", if there ever was on in an articulated IM train, is solved. The "rear only" thing can be solved with some planning. Here B an example. Denver is an inbound city. Equipment goes empty there and there aren't any loads outbound for the equipment. BNSF has to drag the empties back to Chicago. What a waste of diesel fuel. But, there are large meat plants on line at Ft. Morgan, CO and Grand Island, NE. All the outbound fresh beef goes by truck. Just put the RoadRailers (which took loads in to Denver) on the back of the IM train from Denver to Chicago. Make a set out and pick up at Ft. Morgan and Grand Island. And handle the loads on the rear. Ain't no big thing. Haul the freight and send 'em a bill. Yes, you're going to have to have the train do work at these two points. It's not like a new thing. Trains have done work at Ft. Morgan and Grand Island for over 100 years. The alternative is to continue to move empty equipment all the way out of Denver, with zero revenue to cover the costs. Hanging them on the rear will limit flexibility, but the rewards (revenue) will more than offset the costs of the limits. The slack problem, if it exists, can be solved. Ken Understand how dist. power can help and engineer control slack. But, it doesn't prevent run in or run out if not used properly. If you put 2000' of RR behind 8000' of conventional IM - distributed power or not, you can still have the slack run in/out and generate some high forces. Ideally, you want the RR units up front, followed by the DPU, then the rest of the consist.
QUOTE: Originally posted by oltmannd QUOTE: Originally posted by greyhounds Slack is not a problem with putting RoadRailers on the back of an Intermodal train. Niether is positioning them on the rear of a train. If you're worried about slack, just use distributed power. Instead of three locos on the head of the train, put two up front and one in back. Make your pickup behind the third unit. The "Slack Problem", if there ever was on in an articulated IM train, is solved. The "rear only" thing can be solved with some planning. Here B an example. Denver is an inbound city. Equipment goes empty there and there aren't any loads outbound for the equipment. BNSF has to drag the empties back to Chicago. What a waste of diesel fuel. But, there are large meat plants on line at Ft. Morgan, CO and Grand Island, NE. All the outbound fresh beef goes by truck. Just put the RoadRailers (which took loads in to Denver) on the back of the IM train from Denver to Chicago. Make a set out and pick up at Ft. Morgan and Grand Island. And handle the loads on the rear. Ain't no big thing. Haul the freight and send 'em a bill. Yes, you're going to have to have the train do work at these two points. It's not like a new thing. Trains have done work at Ft. Morgan and Grand Island for over 100 years. The alternative is to continue to move empty equipment all the way out of Denver, with zero revenue to cover the costs. Hanging them on the rear will limit flexibility, but the rewards (revenue) will more than offset the costs of the limits. The slack problem, if it exists, can be solved. Ken Understand how dist. power can help and engineer control slack. But, it doesn't prevent run in or run out if not used properly. If you put 2000' of RR behind 8000' of conventional IM - distributed power or not, you can still have the slack run in/out and generate some high forces.
QUOTE: Originally posted by greyhounds Slack is not a problem with putting RoadRailers on the back of an Intermodal train. Niether is positioning them on the rear of a train. If you're worried about slack, just use distributed power. Instead of three locos on the head of the train, put two up front and one in back. Make your pickup behind the third unit. The "Slack Problem", if there ever was on in an articulated IM train, is solved. The "rear only" thing can be solved with some planning. Here B an example. Denver is an inbound city. Equipment goes empty there and there aren't any loads outbound for the equipment. BNSF has to drag the empties back to Chicago. What a waste of diesel fuel. But, there are large meat plants on line at Ft. Morgan, CO and Grand Island, NE. All the outbound fresh beef goes by truck. Just put the RoadRailers (which took loads in to Denver) on the back of the IM train from Denver to Chicago. Make a set out and pick up at Ft. Morgan and Grand Island. And handle the loads on the rear. Ain't no big thing. Haul the freight and send 'em a bill. Yes, you're going to have to have the train do work at these two points. It's not like a new thing. Trains have done work at Ft. Morgan and Grand Island for over 100 years. The alternative is to continue to move empty equipment all the way out of Denver, with zero revenue to cover the costs. Hanging them on the rear will limit flexibility, but the rewards (revenue) will more than offset the costs of the limits. The slack problem, if it exists, can be solved. Ken
QUOTE: Originally posted by DSchmitt QUOTE: Originally posted by ericsp QUOTE: Originally posted by DSchmitt In the SP days, Schneider road railers used to come through Marysville CA on the rear of freight trains. A 2 or 3 day a week scheduled service. They always had a single box car coupled behind them. I don't know why. Could it have been for monitoring equipment? How did I miss this? I have heard about and saw the Swift Roadrailers (unfortunately I did not get to see them until after UP took over). When did the service begin and end? Sorry I don't remember [:(] I know the Swifts started running before the merger. The Schneiders quit running before that. I think, a year or so and that they ran for at least 2 years.
QUOTE: Originally posted by ericsp QUOTE: Originally posted by DSchmitt In the SP days, Schneider road railers used to come through Marysville CA on the rear of freight trains. A 2 or 3 day a week scheduled service. They always had a single box car coupled behind them. I don't know why. Could it have been for monitoring equipment? How did I miss this? I have heard about and saw the Swift Roadrailers (unfortunately I did not get to see them until after UP took over). When did the service begin and end?
QUOTE: Originally posted by DSchmitt In the SP days, Schneider road railers used to come through Marysville CA on the rear of freight trains. A 2 or 3 day a week scheduled service. They always had a single box car coupled behind them. I don't know why. Could it have been for monitoring equipment?
QUOTE: Originally posted by futuremodal Also, aren't DPU's used to keep the slack bunched in the forward consist? So there would be no slack run in or run out.
QUOTE: Originally posted by futuremodal QUOTE: Originally posted by oltmannd QUOTE: Originally posted by futuremodal QUOTE: Originally posted by oltmannd QUOTE: Originally posted by greyhounds Slack is not a problem with putting RoadRailers on the back of an Intermodal train. Niether is positioning them on the rear of a train. If you're worried about slack, just use distributed power. Instead of three locos on the head of the train, put two up front and one in back. Make your pickup behind the third unit. The "Slack Problem", if there ever was on in an articulated IM train, is solved. The "rear only" thing can be solved with some planning. Here B an example. Denver is an inbound city. Equipment goes empty there and there aren't any loads outbound for the equipment. BNSF has to drag the empties back to Chicago. What a waste of diesel fuel. But, there are large meat plants on line at Ft. Morgan, CO and Grand Island, NE. All the outbound fresh beef goes by truck. Just put the RoadRailers (which took loads in to Denver) on the back of the IM train from Denver to Chicago. Make a set out and pick up at Ft. Morgan and Grand Island. And handle the loads on the rear. Ain't no big thing. Haul the freight and send 'em a bill. Yes, you're going to have to have the train do work at these two points. It's not like a new thing. Trains have done work at Ft. Morgan and Grand Island for over 100 years. The alternative is to continue to move empty equipment all the way out of Denver, with zero revenue to cover the costs. Hanging them on the rear will limit flexibility, but the rewards (revenue) will more than offset the costs of the limits. The slack problem, if it exists, can be solved. Ken Understand how dist. power can help and engineer control slack. But, it doesn't prevent run in or run out if not used properly. If you put 2000' of RR behind 8000' of conventional IM - distributed power or not, you can still have the slack run in/out and generate some high forces. Ideally, you want the RR units up front, followed by the DPU, then the rest of the consist. That would be worse. RRs are only good for 400,000# buff. You can't count on a DPU to keep buff forces from the RRs if slack runs in. How bout this: A powerless command cab up front, then the RR's, then the motive power DPU's, then the rest of the consist? Or is slack run in still a problem? Which is more impactful, slack run out or slack run in?
QUOTE: Originally posted by oltmannd You still have plenty of slack in intermodal trains. There are still lots of 90' flats out there plus many single well cars, for example. An 8000' foot IM train would generally have 40-50 "slack points." If the slack were to run in fairly harshly, for whatever reason, the solid block of RRs trailing would be faced with some rather severe deceleration. And since the RRs are slackless so their mass acts as a solid body, and F=ma, you'd create a rather large "F" which, at the least, would start you down the slippery slope of metal fatigue, or at the worst, tear things up right now.
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