Trains.com

Tank Cars Profile

2595 views
15 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    July 2006
  • 152 posts
Tank Cars Profile
Posted by Northtowne on Tuesday, December 14, 2021 9:03 PM

Some tankers have a larger diameter at the ends than in the middle where the fill cap is. Why? Liquid has a level profile unless filled under pressure. Is there an air space at the ends that serves some purpose? This shape surely adds some to the cost of mfg of the unit. (Topic has probably been on before, if so please excuse).

Northtowne

  • Member since
    December 2001
  • From: Northern New York
  • 25,020 posts
Posted by tree68 on Tuesday, December 14, 2021 9:13 PM

Are you sure they are bigger on the ends, or are you seeing cars that are built with a "bend" in the middle?

LarryWhistling
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...

  • Member since
    July 2006
  • 152 posts
Posted by Northtowne on Tuesday, December 14, 2021 9:46 PM

I think the bottoms are level but I will take a closer look. Why would they be bent? At a factory where I worked years ago I watched sheet metal layout men make round pipe fittings that had a slightly different diameter on the ends to connect different pipe sizes. I think I can see the steel round sections that are welded together to make the tanks and even the weld seam diameters grow slightly larger as they build out to the ends of the tanks.

Northtowne 

  • Member since
    December 2001
  • From: Northern New York
  • 25,020 posts
Posted by tree68 on Tuesday, December 14, 2021 9:51 PM

To drain better...

LarryWhistling
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...

  • Member since
    April 2016
  • 1,447 posts
Posted by Shadow the Cats owner on Wednesday, December 15, 2021 7:37 AM

We have started specing all new tank trailers with a 1 inch drop in the middle.  Why when your pumping out from the middle having the lowest point be that spot makes it very easy to force whatever liquids your moving to it.  

  • Member since
    June 2001
  • From: Lombard (west of Chicago), Illinois
  • 13,681 posts
Posted by CShaveRR on Wednesday, December 15, 2021 7:27 PM

If the enlarged height is in the middle, you've hit on the right answer.  You'll find the outlets at the low point.

I thought we were done seeing them, but this past week I saw a couple of newer cars that are narrower toward the center.  This isn't for unloading, but to keep the cars within Plate B or Plate C.  The longer the car is, the narrower the maximum width must be to fit the car within the plate (why do you never see a Plate D on a car?  That plate is the one that governs the coordination between length and width, as well as the length of the whelbase).  

Most modern cars get the width they need by moving the openings away from the centers.

Carl

Railroader Emeritus (practiced railroading for 46 years--and in 2010 I finally got it right!)

CAACSCOCOM--I don't want to behave improperly, so I just won't behave at all. (SM)

  • Member since
    January 2002
  • From: Canterlot
  • 9,575 posts
Posted by zugmann on Wednesday, December 15, 2021 9:18 PM

CShaveRR
Most modern cars get the width they need by moving the openings away from the centers.

Makes spotting them fun at times. 

It's been fun.  But it isn't much fun anymore.   Signing off for now. 


  

The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.t fun any

  • Member since
    May 2005
  • From: S.E. South Dakota
  • 13,569 posts
Posted by Murphy Siding on Friday, December 17, 2021 4:09 PM

zugmann

 

 
CShaveRR
Most modern cars get the width they need by moving the openings away from the centers.

 

Makes spotting them fun at times. 

 

How so?

(I gotta be honest here. I couldn't figure out why it would be fun to spot one. "Hey! Look- It's one of those modern cars with the openings away from the center." Dunce )

Thanks to Chris / CopCarSS for my avatar.

  • Member since
    December 2001
  • 3,139 posts
Posted by chutton01 on Friday, December 17, 2021 4:25 PM

Murphy Siding
(I gotta be honest here. I couldn't figure out why it would be fun to spot one. "Hey! Look- It's one of those modern cars with the openings away from the center." Dunce )


I guess you're joking, but just in case, spotting in the sense of positioning the tank car on a siding for loading or unloading.

  • Member since
    December 2001
  • From: Northern New York
  • 25,020 posts
Posted by tree68 on Friday, December 17, 2021 4:38 PM

Murphy Siding
(I gotta be honest here. I couldn't figure out why it would be fun to spot one. "Hey! Look- It's one of those modern cars with the openings away from the center."  )

Kinda like putting gas in a 50's/60's car.  Where the heck is the fill on this one?

LarryWhistling
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...

  • Member since
    September 2010
  • 2,515 posts
Posted by Electroliner 1935 on Friday, December 17, 2021 10:06 PM

tree68
 Murphy Siding
(I gotta be honest here. I couldn't figure out why it would be fun to spot one. "Hey! Look- It's one of those modern cars with the openings away from the center."  ) 

Kinda like putting gas in a 50's/60's car.  Where the heck is the fill on this one?

Like behind the taillight? Or the license plate?

  • Member since
    December 2007
  • From: Georgia USA SW of Atlanta
  • 11,919 posts
Posted by blue streak 1 on Friday, December 17, 2021 11:51 PM

tree68
Kinda like putting gas in a 50's/60's car.  Where the heck is the fill on this one?

 
What no arrrow on the gas guage?  My arrow points down for fill in middle of back behind license plate.
  • Member since
    March 2016
  • From: Burbank IL (near Clearing)
  • 13,540 posts
Posted by CSSHEGEWISCH on Saturday, December 18, 2021 10:02 AM

The arrow on the gas gauge is a relatively recent addition.  It helps when you get a new car and the fill is on the opposite side compared to the old car.  At any rate, it takes a while to get used to having the fill on the other side.

The daily commute is part of everyday life but I get two rides a day out of it. Paul
  • Member since
    September 2003
  • 21,669 posts
Posted by Overmod on Saturday, December 18, 2021 10:13 AM

The modern equivalent of hiding the fill behind a taillight or license-plate frame is hiding the button or lever for the locking gas-tank door inside the car.  They have been in the center or front of the driver's door, down by the seat, up under the dashboard, in a row of pictorial controls, even inside the glove box.  Often made in a color matching the background to make it impossible to see at night.

Rental companies need to make stick-on glow in the dark arrows that point to the control...

  • Member since
    December 2007
  • From: Georgia USA SW of Atlanta
  • 11,919 posts
Posted by blue streak 1 on Saturday, December 18, 2021 6:58 PM

Ever had to call rental company for a fuel door that would not open?

  • Member since
    September 2003
  • 21,669 posts
Posted by Overmod on Tuesday, December 21, 2021 7:41 PM

Usually they had manuals in the glove compartment that would explain where the release was.

Much more fun was the '91 Sovereign, which has a locking gas filler door without... as it turns out... any internal release at all (you pull up on the driver's door lock handle to unlock the doors and trunk).  Fascinatingly English is that there's a dash control to lock the doors, but not to unlock them.  You can release the flap by going in the trunk -- but the pot-metal trunk latch loves to stick in latched position, making you dependent on the electric trunk unlock to be able to get to it... 

The '90 had a large plastic lever to open the flap, down next to the driver's seat.  This disintegrated the second time I pulled it, so I got proficient at opening the trunk and knowing exactly where to push to open the latch.  Until the English steel and English welds failed and the door came off in my hand -- not a bug but a feature, in this case!

I still remember the joys of discovering '70s fuel-crisis locking gas caps... when you had no key.  THAT is a sinking feeling that no manual can help.

Join our Community!

Our community is FREE to join. To participate you must either login or register for an account.

Search the Community

Newsletter Sign-Up

By signing up you may also receive occasional reader surveys and special offers from Trains magazine.Please view our privacy policy