and he notes -
A lo-o-ong time ago I asked this question about hauling solid gasoline trains during WWII and was told that the boxcar helped even out the jolt as the loco either pulled or slowed the train. Santa Fe RR did restrict speed on tank trains due to tracking problems created by surge pressure in the cars. Since liquids expand in the hot sun, tank cars cannot be filled to the brim. When running at speed the rocking of the car as well as changes in speed causes the liquid to slosh back and forth within the car. Surge plates help reduce this action but not entirely. One or two boxcars behind the locomotive seem to alleviate the problem. I seem to recall that a boxcar in front of the caboose mad the rear end crew feel safer. To my knowledge no solid tank trains were lost due to accidents during WWII. A similar problem existed during the steam era when tender water levels began to drop when running causing, the water to slosh back and forth like a wave, especially in big tenders. Again the boxcar tended to reduce the effect.on the tank cars. More than once I've seen water surge over the rear of the tender when a commuter train started from North Station in Boston. They were usually short so a hot shot engineer could start a train with a jolt and get up to speed quickly. Tenders were usually filled to the top at Mystic Enginehouse so the trains could make it to their end terminals without taking on water. I can only imagine what the effect would be on patrons riding in the first car with the windows open on a hot summer day, but as a rule that first car was a combine - maybe the railroad knew the consequences! I don't know of propane or chemical cars have this problem, but I do see Kaolin cars heading to Portland on the B&M (now Guilford) near my home and they are usually in the middle of the train. Raleigh in 7 degree Maine! At 05:14 PM 1/3/2008, Larry Langford wrote: >For what it's worth, I saw an ethanol train crossing the Thebes, IL/MO >bridge last month with a single box car behind the power. > >L > >-----Original Message----- >From: <mailto:S-Scale%40yahoogroups.com>[email protected] >[mailto:[EMAIL PROTECTED] On Behalf Of >ken garber >Sent: Thursday, January 03, 2008 3:27 PM >To: <mailto:S-Scale%40yahoogroups.com>[email protected] >Subject: Re: {S-Scale List} Heavy Cars......(problems with) > >On 1/3/08, raleigh <<mailto:raleigh%40ttlc.net>[EMAIL PROTECTED]> wrote: > > and he notes - > > > > The only practice I can recall for freight car placement in a train > > was the use of a box car behind the tender when the train was a solid > > string of tank cars. This was (also if I recall) due to tracking problems. > >Don't know if they still do it, but a car would be placed ahead of >special dangerous cars such as sulphuric acid tanks. And way back >when... ahead of the caboose > >Check some of the rail mags to see if they do that for Ethenol traffic. > > > > > On a model railroad, brass or other heavily weighted cars may pose a > > problem if the lighter cars are spotted ahead of them but that's not > > a prototypical dilemma. > >Many years ago the NS placed an empty 85' flat at the head of a >(transfer) train. Unfortunately that train needed to take a 'loop >track' and when they started up, all they did was pop the car on the >ground. > >The locos stayed on track but blocked the grade crossing. > >KG > > > > > Raleigh in 'Deep-Freeze' Maine > >Yahoo! Groups Links > > [Non-text portions of this message have been removed] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/S-Scale/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/S-Scale/join (Yahoo! ID required) <*> To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
