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simple conversion, approximate tank car length from tank car capacity?

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simple conversion, approximate tank car length from tank car capacity?
Posted by IDRick on Tuesday, April 2, 2019 6:30 PM

Is there a simple rule of thumb for estimating tank car length from stated capacity?  Manufacturer's and sellers will tell you tank car capacity but never the length...  Grrr...  I'd like tank cars in the 50 to 55 ft range.

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Posted by davidmurray on Tuesday, April 2, 2019 8:16 PM

I just measureed a GULF gasoline tanker  of 8000 gal capacity as being very close to the same length as a 40' boxcar.

Only one data point, anyone got some more?

Dave

 

David Murray from Oshawa, Ontario Canada
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Posted by mbinsewi on Tuesday, April 2, 2019 8:20 PM

No, not that I know of.  Shippers have gallons of a product to ship.  Length of the car it's shipped in doesn't matter, only it's rated capacity.

You can figure it out, a tank 10' in diameter, 50 long,  5' x 5'= 25x3.14=78.5 cu.ft. x 50' = 3925 cu.ft. x 7.48 = 29,359 gals.

Most products need a certain amount of space at the top, for expansion, so a 30,000 gal capacity tank car car is probably 55' long, (judging by the calc for the 50' car, filled to the brim).  That would be just the tank.

You want cars in the 50' to 55' range, so they could have a capacity of maybe 28,000 to 30,000 gals?

Most model tank cars you buy are going to be some where in the your range, the 65' ft. cars are real obvious, there longer.

How precise do you need to be?  Just buy some tank cars.  What ever the little decal on it that says it's rated capacity, will be right for the length.

Mike.

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Posted by maxman on Tuesday, April 2, 2019 9:04 PM

IDRick

Is there a simple rule of thumb for estimating tank car length from stated capacity?  Manufacturer's and sellers will tell you tank car capacity but never the length...  Grrr...  I'd like tank cars in the 50 to 55 ft range.

 
I don't think so, either.  Isn't that what a scale rule is for?
 
I think that what the commodity is has a bearing on car length.  Gallons are a volume measurement.  Different commodities have different densities:
 
 
So assuming that the idea is to fill a car up to the allowable rail load, a longer car is capable of carrying more gallons of a less dense liquid.
 
At least that's my theory and I'm sticking to it.
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Posted by NHTX on Tuesday, April 2, 2019 9:05 PM

     IDRick:

     Tank car capacity cannot be accurately determined based solely on tank length.  Diameter is also a major factor in tank car capacity.  Diameter is  affected by whether or not a tank in insulated or equipped with heater coils.

     Because you didn't mention your scale or era modeled, I will refer to HO models when I refer you to Athearn's BB 62' tanker, the Genesis 65' LPG cars and the Genesis 20,000 gallon car which is in the 50 foot range.  Atlas offers a 23,500 gallon and 25,500 gallon car, both of which exceed fifty feet in length.  Scale Trains offers 30,145 gallon ethanol cars which exceed fifty feet in length over strikers.  Walthers offers cars of 23,000 gallon capacity with a length of 54 feet.

     Cars exceeding 50 feet over strikers became common in the 1970s and rule today's rails.  The cargo to be handled dictates tank size.  For instance, a gallon of sulfuric acid, 98% weighs 15.35 pounds while a gallon of No. 6 fuel oil only weighs 8.06 pounds.  This will make a big difference in tank size to keep the car within the 286,000 pound gross weight limit of most rail lines.  A study of the Official Railway Equipment Register will show few tank car operators list capacity in gallons.  Like other freight cars, the capacities are in pounds,] because the railroads operate on a basis of weight.

 

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Posted by IDRick on Tuesday, April 2, 2019 9:05 PM

Wahoo!  I found a great link that shows car capacity and length of tank cars designed to haul specific products, see:   https://www.gbrx.com/manufacturing/north-america-rail/tank-cars/ 

Car capacity of run around tracks and sidings varies depending on car length.  My goal is to standardize length of freight rolling stock to less than 60 feet which enables me to establish length of run around tracks.  Also, since car length is not usually reported by sellers, I wanted some way of approximating car length.  The above link gives me data to use for my approximations.   I know, I know, majoring in minors but I was curious and now I know!  :-)  Thanks to those who assisted me in my quest, big hat tip!

Thanks Maxman and NHTX, didn't see your comments until posting.  I knew a rule of thumb would have significant error depending on the load, now I have a source to better estimate length.

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Posted by mbinsewi on Tuesday, April 2, 2019 9:48 PM

You'll have to tell the shippers that use your railroad, "Nothing over 60', over the couplers, will be allowed, that's it, anything longer and you will not ship via my railroad".

Sounds reasonable.    Laugh

Mike.

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Posted by IDRick on Tuesday, April 2, 2019 10:58 PM

Since I buy the cars that show up on the layout, I can control size...  It would be a surprise if an unknown car showed up on my layout!Surprise

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Posted by BRAKIE on Wednesday, April 3, 2019 4:57 AM

mbinsewi
"Nothing over 60', over the couplers, will be allowed, that's it, anything longer and you will not ship via my railroad".

The customer's reply.

That's ok..We will use trucks for transloading on the Hooten Hollow & Western..Feel free to remove your switch into our plant. Black EyeLaugh

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

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Posted by NHTX on Wednesday, April 3, 2019 6:16 AM

     IDRick:

     Thanks for the tip on the Greenbrier site.  My interests are 1980-1986.  Thankfully the changes in car design are not as radical as those in locomotives!

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Posted by mbinsewi on Wednesday, April 3, 2019 6:51 AM

IDRick
Since I buy the cars that show up on the layout, I can control size..

You might want to check out other tank car manufacturers and see if they give technical info on their cars.

Procor, Union Tank Car Co., Trinity, American Tank and Foundry,  just to name a few.

I'm not sure who's model you can buy that represents Greenbrier.

Mike.

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Posted by IDRick on Wednesday, April 3, 2019 9:11 AM

mbinsewi

 

IDRick
Since I buy the cars that show up on the layout, I can control size..

 

You might want to check out other tank car manufacturers and see if they give technical info on their cars.

Procor, Union Tank Car Co., Trinity, American Tank and Foundry,  just to name a few.

I'm not sure who's model you can buy that represents Greenbrier.

Mike.

 

 

Yes, I had checked these sources before posting but alas, only Greenbrier gave capacity and length.  Just wanted a general guideline so it suits my purpose but probably not totally accurate relative to MR tank cars as manufactured. {shrug}

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Posted by kasskaboose on Wednesday, April 3, 2019 9:23 AM

Does the term "whale belly" indicate a tank car's length and/or capacity? 

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Posted by mbinsewi on Wednesday, April 3, 2019 9:37 AM

kasskaboose
Does the term "whale belly" indicate a tank car's length and/or capacity? 

Confused ?  Neither.  It's a "description" of it's appearance.

Mike.

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Posted by IDRick on Wednesday, April 3, 2019 9:42 AM

kasskaboose

Does the term "whale belly" indicate a tank car's length and/or capacity? 

 
Union Tank does not provide dimensional data for their rail cars (at least none that I can find).  A whale belly car will carry more product than a conventional tank car of the same length and construction.  I do not own any whale belly tankers nor do I plan to purchase any so cannot provide any more information.
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Posted by NHTX on Wednesday, April 3, 2019 5:52 PM

     If you go to http://www.rr-fallenflags.org/acfx/acfx./htm and scroll down the listing to ACFX 17074, you will see one of the "whalebelly" tankcars.  They are almost extinct due to the 40 year rule.

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