Wikipedia

Tank car

Not to be confused withArmored car (military).

Atank car(International Union of Railways(UIC):tank wagon) ortankeris a type ofrailroad car(UIC: railway car) orrolling stockdesigned to transportliquidandgaseouscommodities.

Modern tank cars carry all types of liquid and gaseous commodities
Rows of tank cars at a railyard in the Midwestern United States[1]

History

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Timeline

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The following major events occurred in the years noted:

  • 1865:Flatcarswith bandedwooden planksor decking mounted on top are employed for the first time to transportcrude oilfrom the fields ofPennsylvaniaduring thePennsylvanian oil rush.Laurence Myers of Philadelphia invented theRotary Oil Car,as he named it. It was an improvement on a patent from 1851 of a freight car for transporting coal. The new invention patented on July 18, 1865, was for the transportation of crude oil and petroleum. It was the first appearance of an oil tank on a railroad flatcar. Three books mention his invention.[2][3][4]
  • 1869: Wrought iron tanks, with an approximate capacity of 3,500US gal(13m3;2,900imp gal) per car, replace wooden tanks.
  • 1888: Tank-car manufacturers sell units directly to theoil companies,with capacities ranging from 6,000 to 10,000 US gal (23–38 m3;5,000–8,300 imp gal).
  • 1903: Tank-car companies develop construction safety standards. More than 10,000 tank cars are in operation.
  • 1915: A classification system is developed by the tank-car industry to ensure the correct match of car type to product being shipped. Some 50,000 tank cars are in use.
  • 1930: 140,000 tank cars transport some 103 commodities.
  • 1940s: Virtually every tank car is engaged in oil transport in support of thewar effort.
  • 1945–1950:Weldingreplacesrivetingin car construction (both underframes and tanks) for the major manufacturers, includingAmerican Car & FoundryandGeneral American.
  • 1950:Pipelinesandtank trucksbegin to compete for liquid transport business.
  • 1963: TheUnion Tank Car Companyintroduces the "Whale Belly" tank car.

Usage

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North America

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AAR Plate-C loading gauge
Inside the valve housing on top of a tank car in the United States, with amagnetic level gaugepulled out[1]

Many variants exist due to the wide variety ofliquidsand gases transported. Tank cars can bepressurizedor non-pressurized,insulatedor non-insulated, and designed for single or multiple commodities. Non-pressurized cars have various fittings on the top and may have fittings on the bottom. Some of the top fittings are covered by a protective housing. Pressurized cars have a pressure plate, with all fittings, and a cylindrical protective housing at the top. Loading and unloading are done through the protective housing.

Tank cars are specialized pieces of equipment. As an example, the interior of the car may be lined with a material, such asglass,or other specialized coatings to isolate the tank contents from the tank shell. Care is taken to ensure that tank contents are compatible with tank construction.

As a result of this specialization, tank cars have generally been "one-way" cars. Other cars, likeboxcars,can easily be reloaded with other goods for the return trip. Combinations of the two types were attempted, such as boxcars with fluid tanks slung beneath the floors. While the car could certainly carry a load in both directions, the limited tank size made this unsuccessful.

A large percentage of tank cars are owned by companies serviced by railroads instead of the railroads themselves. This can be verified by examining thereporting markson the cars. These marks invariably end inX,meaning that the owner is not acommon carrier.

Within the rail industry, tank cars are grouped by their type and not by the cargo carried. Food-service tank cars may be lined withstainless steel,glass, or plastic. Tank cars carryingdangerous goodsare generally made of different types of steel, depending on the intended cargo and operating pressure. They may also be lined with rubber or coated with specialized coatings for tank protection or product purity purpose. The tank heads are also stronger to prevent ruptures during accidents. The whale-belly type is giving way to higher-capacity (longer), yet standard-width,AARPlate "C",cars.

All tank cars undergo periodic inspection for damage and corrosion.Pressure relief valvesare inspected at every loading. Pressurized cars are pressure-tested regularly to ensure the integrity of the tank.

All tank cars operating throughout North America today feature AAR Type Edouble shelf couplersthat are designed to prevent disengaging in event of an accident or derailment. This reduces the chance of couplers puncturing adjacent tank cars. However, if cars are prevented from disengaging in a derailment, the torsional forces of a derailing car can be transferred to other cars, resulting in the derailment of the adjacent cars.[5][6]

Insulated cars (which may also incorporate heating or refrigeration systems) are used when the contents must be kept at a certain temperature. For example, the Linde tank car depicted below[which?]carries liquefiedargon.Cars designed for multiple commodities are constructed of two or more tanks (compartments). Each compartment must have separate fittings. The lower capacity and added complexity of multicompartment cars means that they make up a small percentage of the tank car inventory.

Specialized applications

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Pressure tank car for compressed liquified gasses

DOT-111

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Main article:DOT-111 tank car

The DOT-111 tank car, designed to carry liquids such asdenaturedfuel ethanol,is built to a US standard. The design has been criticized on safety grounds.[7]The train in theLac-Mégantic derailmentof 2013 was made up of 72 of these cars.[8]

DOT-112

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DOT-112 tank carsare used in North America to carry pressurized gases. One of these tank cars exploded in Waverley, TN, killing 16, when aLouisville & Nashvilletrain derailed. While the clean up efforts were under way, the tank car, UTLX 83013, ended up exploding from aBLEVE.

DOT-114

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DOT-114 tank carsare used in North America to carry pressurized gases.

Milk cars

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Main articles:Milk carandBritish railway milk tank wagon
A historicalmilk tank carfor bulk loading at theIllinois Railway Museum.

A milk car is a specialized type of tank car designed to carry rawmilkbetween farms,creameries,and processing plants.

Milk is now commonly chilled, before loading, and transported in a glass-lined tank car. Such tank cars are oftenplacardedas "Food service use only".

Liquid hydrogen tank car

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Main article:Liquid hydrogen tank car

Tank cars of this type are designed to carrycryogenicliquid Hydrogen(LH2). North American cars are classified as DOT113, AAR204W, and AAR204XT[9]

Pickle cars

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A pickle car was a specialized type of tank car designed to carrypickles.This car consisted of several wooden or metal vats (typically three or four) and was often roofed. Pickles which are preserved in salt brine were loaded through hatches in the roof.

Tank containers

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Type of shipping containers mounted on aspine car:Tank container(left), and anopen-top shipping containerwithcanvascover (right)
Further information:Tank containerandLiquid hydrogen tanktainer

A tank container, also known as ISO tank, is a specialized type ofcontainerdesigned to carry bulk liquids, such as chemicals,liquid hydrogen,gasesand food grade products. Both hazardous and non hazardous products can be shipped in tank containers. A standard tank container is 20 feet (6.10 m) long, 8 feet (2.44 m) high and 8 feet (2.44 m) wide. The tank, which is made from stainless steel, is held within a box-shaped frame with the same shape as anintermodal container.This allows it to be carried on multiple modes of transport, such as truck, rail and ship.

Torpedo wagons

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Main article:Ladle transfer car
Torpedo car

Atorpedo carorbottle caris a type of railroad car used insteel millsto haulmoltenpig ironfrom theblast furnaceto begin the process of primarysteelmaking.

Thethermally-insulatedvessel is mounted ontrunnions,and designed to endure extremely high temperatures, as well as keeping the metal in a molten state over extended periods of time. The vessel can be pivoted along its longitudinal axis to empty the pig iron into aladle.The name is derived from the vessel's resemblance to atorpedo.

Vinegar cars

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Wooden vinegar car, at the Toronto Railway Museum inRoundhouse Park.

A vinegar car is a specialized type of tank car designed to transportvinegar.The largest such car built was built byMorrison Railway Supply Corporationin 1968. The car's underframe included all of the modern facets of freight car design includingroller bearingtrucksand cushioning devices built by FreightMaster, while the tank that rode on it, made ofDouglas fir,had a capacity of 17,100 US gallons (65 m3;14,200 imp gal). The car, in what has been called 'the largest wooden tank car ever built', took 18 months to build.

TheReinhart Vinegar Carcan be seen at theToronto Harbourfront Museum.[10]

Vinegar is now moved in ordinary tank cars lined with glass, plastic, oralloy steel.[11]

"Whale belly" cars

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In the early 1960s, theUnion Tank Car Companyintroduced a series of "whale belly" tank cars which offered increased capacity. These cars carried from 33,000 US gallons (125 m3;27,478 imp gal) in CSOX #31084[12]to as much as 63,000 US gallons (238 m3;52,458 imp gal) inGATX#96500, which had been conceived as a 'rolling experiment'. The largest tank car ever placed into regular service,UTLX #83699,was rated at 50,000 US gallons (189 m3;41,634 imp gal). It entered service in 1963 and was used for over 20 years. GATX 96500 is now on display at theNational Museum of TransportationinSaint Louis, Missouri.This car is 98 feet (29.87 m) long, weighs 175,000 lb (79,400 kg) empty and rides on four two-axletrucksfor weight distribution. It transported diverse substances, such asliquefied petroleum gas(LPG) and anhydrousammonia.

Safety

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A tank car carryingchlorine,displayinghazardous materialsinformation including aU.S. DOT placardshowing aUN number[1]

WhereAAR couplersare fitted, theAAR type "F" coupler[13]is preferred as these are less likely to become separated in a derailment and become a puncture hazard for other tank cars. A type "E" coupler that hasshelves over and underthe coupler that prevent the coupler sliding out of position after aderailmentis used on somehazardous materialstank cars.[14][15]

In addition, some types of tank cars have a second end plate visible from the exterior, to further avoid end punctures.

It is also preferable if eachtap (valve)is recessed within the body of the tank so as to present a reduced knock-off hazard during a derailment.[citation needed]

Tank cars have been involved in many rail disasters, including theLac-Mégantic derailmentinQuebecin 2013, theNishapur train disasterin Iran in 2004, and theViareggio train derailmentin Italy in 2009.

Outside North America

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Narrow gaugetank wagon,750 mm(2 ft5+1⁄2in) gauge
Tankwagon on a Russianfire train.
A tank wagon (forphosphoric acid) near the wagon repair shop ofVRin theViinikkadistrict of the city ofTampere,Finland

Outside ofNorth America,tank cars are also known astank wagonsortanker wagons.In theUnited Kingdomtank wagons were traditionally four-wheel vehicles. Some long-wheelbase four-wheelers are still in use butbogievehicles are now used as well.

See also

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Notes

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  1. ^abcBeaucham, Catherine C. (August 2023)."Evaluation of Potential Exposures to Railway Hazardous Material Inspectors"(PDF).U.S. National Institute for Occupational Safety and Health(Health Hazard Evaluation Report).Retrieved2024-05-04.
  2. ^Fuel Oil in Industry
  3. ^The Petroleum Industry
  4. ^The Petroleum Handbook
  5. ^"Railway Investigation Report R13E0142".tsb.gc.ca.26 February 2015.
  6. ^"AGENDA - BACKGROUND, TANK CAR COMMITTEE, SUBCOMMITTEE 1, Colorado Springs, CO, October 16-17, 2013"(PDF).Archived fromthe original(PDF)on 2015-11-17.Retrieved2015-04-28.
  7. ^Stancil, Paul L."DOT-111 Tank Car Design"(PDF).NTSB Office of Railroad, Pipeline and Hazardous Materials Safety. Archived fromthe original(PDF)on Nov 10, 2013.
  8. ^"Lac-Mégantic: la sécurité du type de wagons déjà mise en cause"(in French).Radio-Canada.July 8, 2013.RetrievedJuly 8,2013.
  9. ^NOAA's Office of Response and Restoration: Chemical Response ToolArchived2008-12-20 at theWayback Machine
  10. ^Vinegar car
  11. ^"Week at a glance: Vinegar by rail - in giant wooden tanks".Railway Age.165(17): 11. October 28, 1968.
  12. ^"CSOX #31084".RetrievedJuly 23,2019.
  13. ^"TypeF coupler".RetrievedJuly 23,2019.
  14. ^"E TYPE COUPLER, - Tedrail".RetrievedJuly 23,2019.
  15. ^"Double Shelf Couplers Tank Cars - Bing images".www.bing.com.RetrievedJuly 23,2019.

References

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