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Double-stack rail transport

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(Redirected from Double stacked container trains) Railroad cars carrying two layers of intermodal containers For double-decker passenger trains and coaches, see Bilevel rail car.
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A container train passing through Jacksonville, Florida, with 53 ft (16.15 m) containers used for shipments within North America

Double-stack rail transport is a form of intermodal freight transport in which railroad cars carry two layers of intermodal containers. Invented in the United States in 1984, it is now being used for nearly seventy percent of United States intermodal shipments. Using double stack technology, a freight train of a given length can carry roughly twice as many containers, sharply reducing transport costs per container. On United States railroads, special well cars are used for double-stack shipment to reduce the needed vertical clearance and to lower the center of gravity of a loaded car. In addition, the well car design reduces damage in transit and provides greater cargo security by cradling the lower containers so their doors cannot be opened. A succession of larger container sizes have been introduced to further increase shipping productivity in the United States.

Double-stack rail operations are growing in other parts of the world, but are often constrained by clearance and other infrastructure limitations.

History

Southern Pacific Railroad (SP), and Robert Ingram, of SeaLand, debuted the double-stack intermodal car in 1977. SP and Ingram jointly designed the first car with ACF Industries in 1976. At first it was slow to become an industry standard, then in 1984 American President Lines, started working with the Union Pacific Railroad and that same year, the first all double-stack train left Los Angeles, California for South Kearny, New Jersey, under the name of "Stacktrain" rail service. Along the way the train transferred from the UP to the Chicago and North Western Railway and then to Conrail.

Sizes and clearances

AAR Plate-H loading gauge

Double-stack cars come in a number of sizes, related to the standard sizes of the containers they are designed to carry. Well lengths of 12.19 m (40.0 ft), 14.63 m (48.0 ft) and 16.15 m (53.0 ft) are most common. Heights range from 2.44 m (8 ft 0 in) to 2.908 m (9 ft 6+1⁄2 in) ("high cube").

Double stack requires a higher clearance above the tracks, or structure gauge, than do other forms of rail freight. Double-stack cars are most common in North America where intermodal traffic is heavy and electrification is less widespread; thus overhead clearances are typically more manageable. Nonetheless, North American railroads have invested large sums to raise bridges and tunnel clearances along their routes and remove other obstacles to allow greater use of double stack trains and to give them more direct routes. Outside North America some rail routes have been built or upgraded to such standards as to allow both electrification with overhead wires and double stacking.

CSX lists three clearance heights above top of rail for double stack service:

  • Doublestack 1 — 18 ft 2 in (5.54 m)
  • Doublestack 2 — 19 ft 2 in (5.84 m)
  • Doublestack 3 — 20 ft 2 in (6.15 m)
  • Doublestack 4 — 20 ft 3 in (6.17 m)

The last 2 clearances offer the most flexibility, allowing two high cube containers to be stacked.

Stacking containers

Load bearing of container stacking is at the 40-foot coupling

Forty-foot containers are the standard unit length and load bearing points are at the ends of such containers. Longer containers, such as 45, 48 and 53 feet long, still have the load bearing points 40 feet apart, with the excess protruding equally outside this length. Therefore, 40-foot containers, or larger, can be stacked on 20-foot containers if there are two 20-foot containers in a row; however, 20-foot containers cannot be stacked on top of 40-foot or longer containers. The possible double-stacking patterns are:

  • Two 20 ft in lower and one 40 ft (or longer) in upper stack (allowed in India, China, US)
  • One 40 ft in lower and another 40 ft (or longer) in upper stack (allowed in India, US)
  • Two 20 ft in lower and another set of two 20 ft in upper stack.

The container coupling holes are all female and double male twistlocks are required to securely mate container stacks together.

Dwarf containers

China had started to experiment using reduced-size containers to be stacked on to normal containers to allow transport under 25 kV overhead line electrification.

India has started to build a series of dwarf container for domestic transport to be run under 25 kV electrification. With a height of 6 feet 4 inches (1,930 mm) they are 662 mm shorter than ISO shipping containers but 162 mm wider while still allowing for 67% more capacity when double stacked as compared to single stack ISO container. The width is comparable to that of North American 53-foot containers.

Weights

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Containers have weight limits designed to allow their transport by road trucks, which have lower weight limits than trains. Outside the U.S., a common limit for railways is 8 tonnes per metre (8.1 short ton/yd; 7.2 long ton/yd) train length and 22.5 tonnes (22.1 long tons; 24.8 short tons) per axle. A four axle container car can take 90 tonnes (99.2 short tons; 88.6 long tons). Since a container is limited to 30.5 tonnes (33.6 short tons; 30.0 long tons), even including the empty weight of the rail car, single stacking uses only part of the load capacity of the railway. A 20-foot (6.1 m) container is limited to 24 tonnes (26.5 short tons; 23.6 long tons) and two such can fit into a car for a 40-foot (12.2 m) container, or even three if double-stacking, but not four unless very high axle load is permitted. The North American railways permit two 53-foot (16.15 m) containers as shown in the images on this page.

Another consideration is the maximum weight of a train. A maximum length train in Europe, 750 m (2,461 ft) long can have 50 container cars with a total weight of 2,250 tonnes (2,480 short tons; 2,210 long tons), and more if 20 ft containers are included. This is not far from the limit using standard European (freight) couplers.

Operations

North America

Intermodal containers shipped by rail within North America are primarily 53 feet (16.15 m) long, with trailer-on-flat-car (TOFC) units used as well. The 53-foot length reflects a common maximum length for highway semi-trailers, which varies by state. Major domestic intermodal carriers include:

Containers shipped between North America and other continents consist of mostly 40-foot (12.19 m) and some 45-foot (13.72 m) and 20-foot (6.10 m) containers. Container ships only take 40's, 20's and also 45's above deck. 90% of the containers that these ships carry are 40-footers and 90% of the world's freight moves on container ships; so 81% of the world's freight moves by 40-foot containers. Most of these 40-foot containers are owned by non-U.S. companies like Maersk, MSC, and CMA CGM. The only U.S. 40-foot container companies are leasing companies like Textainer, Triton International, and CAI Leasing.

Low bridges and narrow tunnels in various locations prevent the operation of double-stack trains until costly upgrades are made. Some Class I railroad companies in the U.S., often in partnership with government agencies, have implemented improvement programs to remove obstructions to double-stack trains. Double-stack projects include:

Outside North America

Double stack train on the Panama Canal Railway

On the vast majority of its network, Europe has more restricted loading gauge and train weight limits as well as axle load limits. In other words, many bridges and tunnels are too low for double-stacking. In addition, since European electrification standards generally predated double stacking and were not designed to accommodate for larger clearances than those permitted by existing bridges and tunnels, the overhead catenary in Europe is also too low to accommodate double stacking. Only a few newly built routes make accommodation for possible double stacking in the future such as the Betuweroute in the Netherlands which however links to no other railway line allowing double stacking.

Standard gauge railways in North America and China must use special well cars to lower the center of gravity, fit within the loading gauge and in China allow double stack trains to run under specially heightened overhead lines. 1,676 mm (5 ft 6 in) broad gauge used in India enables trains to carry standard shipping containers double-stacked on standard flat wagons. Flat wagons, in addition to being much less expensive than well wagons, can carry more containers in a given length of train. Indian Railways is able to carry containers double-stacked on standard flat wagons at 100 km/h (62 mph). Experiments with triple-stacked operation using lower, 1,981 mm (6 ft 6 in) containers, were done unsuccessfully in 2006. Experiments in India for double stacking using flatcars under 25 kV AC overhead lines set 7.45 m (24 ft 5+1⁄4 in) above rail have begun with funds given by Japan.

See also

References

  1. Kaminski, Edward S. (1999). American Car & Foundry Company: A Centennial History, 1899–1999. Wilton, California: Signature Press. ISBN 0963379100.
  2. "Railroad Operational Panel". Transportation Law Journal, Vol. 28 (2000).
  3. "A new fleet shapes up. (High-Tech Railroading)". Railway Age. September 1, 1990.
  4. "AAR Open Top Loading Rules Manual (August 2020) - Appendix A" (PDF). p. 238. Archived from the original (PDF) on 2021-02-24.
  5. "Guide to Railcars". Archived from the original on March 8, 2011.
  6. Singh, Sukhbir (May 2009). "Double-stack under the wires" (PDF). Railway Gazette International.
  7. "Commentary: Electrify California's Trains Now". 3 December 2020.
  8. ^ "CSX System Clearance Map— Doublestack Routes". Retrieved July 26, 2019.
  9. "AAR Open Top Loading Rules Manual (August 2020) - Appendix A" (PDF). Archived from the original (PDF) on 2021-02-24.
  10. "CAIN-NSC-HDWELL_16.jpg". progressiverailroading.com.
  11. Vishwas Kothari (2018-07-10). "Indian railways introduces first double stack dwarf containers". Times of India.
  12. "Table 3-6: Semitrailer Length Limitations on National Truck Network by State". U.S. Department of Transportation, Federal Highway Administration.
  13. Triton
  14. CAI
  15. "Norfolk Southern opens Heartland Corridor". Railway Gazette International. September 9, 2010.
  16. "CSX Announces National Gateway to Improve Flow of Freight". CSX. May 1, 2008.
  17. "New Commonwealth Railway line set to open". Trains Magazine. December 16, 2010.(subscription required)
  18. Battagello, Dave (November 1, 2011). "Rail tunnel awaiting government funds". Windsor Star.
  19. Transportación marítima mexicana (TMM)
  20. "Low center of gravity". Archived from the original on March 21, 2011.
  21. ^ Das, Mamuni (October 15, 2007). "Spotlight on double-stack container movement". The Hindu Business Line. Retrieved February 25, 2009.
  22. Das, Mamuni (October 29, 2007). "Green signal for triple-stacks on diesel routes". The Hindu Business Line. Archived from the original on 30 October 2007.
  23. Rao, Raghvendra (October 10, 2006). "Rlys to operate triple-stack container trains". Indian Express.
  24. "Photo Gallery: IRJ". IRFCA. Archived from the original on October 7, 2008.
  25. Dayal, Raghu (May 2009). "Preparing to handle double-stack containers". Railway Gazette International: 46.
  26. "Reaching up". Railway Gazette International. August 2009. p. 17. Archived from the original on 2011-06-15. Retrieved 2010-09-17.
  27. "Double stacked to Perth". Parkes Champion Post. July 28, 2008. Archived from the original on 2008-07-29. Retrieved 2010-09-17.
  28. "2008-2024 Interstate and Hunter Valley Rail Infrastructure Strategy" (PDF). ARTC. June 30, 2008.
  29. "Service offering | Inland Rail". inlandrail.artc.com.au. Retrieved 2019-02-09.
  30. "Brado anuncia investimentos de R$30 milhões em vagões double stack na Intermodal South America".(in portuguese)
  31. "Rumo vence trecho de 1,5 mil quilômetros da Ferrovia Norte-Sul". 28 March 2019.(in portuguese)
  32. "Aerodynamic Effects Caused by Trains Entering Tunnels". ResearchGate. Retrieved 2020-07-01.
  33. "非人狂想屋 | 你的火车发源地 » X2K双层集装箱行驶在京沪线" (in Chinese (China)). Retrieved 2021-03-16.
  34. ^ "宁启铁路复线电气化工程开工仪式在江苏泰州举行". www.gov.cn. Retrieved 2021-03-16.
  35. sina_mobile (2017-01-21). "中国跨度最大公铁两用钢拱桥合龙(图)". news.sina.cn. Retrieved 2021-03-16.
  36. "「通沪铁路7月运营，宁启-通沪路增开动车组38对」- 南通房产超市". nt.fccs.com. Retrieved 2021-03-16.
  37. "上海铁路局：宁启铁路4月11日起进行动态检测". inews.ifeng.com. Retrieved 2021-03-16.
  38. "广珠铁路首趟货运列车从珠海高栏港站首发(图)-搜狐新闻". news.sohu.com. Retrieved 2021-03-18.
  39. "京九铁路（南昌局段）电气化改造工程完成挂网架线". www.gov.cn. Retrieved 2021-03-16.
  40. "京九铁路将可开行双层集装箱列车_滚动新闻_新浪财经_新浪网". finance.sina.com.cn. Retrieved 2021-03-16.
  41. "图文：京九北线电气化铁路进行重载货车试运行-搜狐新闻". news.sohu.com. Retrieved 2021-03-16.
  42. "东陇海铁路可走双层集装箱列车_新闻中心_新浪网". news.sina.com.cn. Retrieved 2021-03-18.
  43. "穿山港铁路支线开建 可跑双层集装箱火车_中国宁波网_民生·城事". news.cnnb.com.cn. Retrieved 2021-03-16.
  44. "运能提高38%，国内首趟双层集装箱海铁联运班列舟山港首发". weibo.com. Retrieved 2020-07-01.
  45. "非人狂想屋 | 你的火车发源地 » HXD1B牵引双层集装箱列车" (in Chinese (China)). Retrieved 2020-07-01.
  46. "甬金铁路全线开工！可开行双层集装箱列车". zj.zjol.com.cn. Retrieved 2021-03-16.
  47. "重大进展！金甬铁路全线迈入架梁施工阶段". Archived from the original on 2021-09-17.
  48. "兰渝铁路岷县至广元段正式开通运营". www.gansu.gov.cn. Retrieved 2021-03-16.
  49. "兰渝铁路广元至重庆段今起开行动车 运行时间压缩1.5小时-新华网". www.xinhuanet.com. Retrieved 2021-03-16.
  50. "贵阳经南宁至钦州拟建双层集装箱铁路-新华网". www.gx.xinhuanet.com. Archived from the original on June 18, 2020. Retrieved 2021-03-16.
  51. "未来15年高铁建设强度仍将高于普速铁路 着力发展高铁快递快运-中经实时报-中国经营网". www.cb.com.cn. Retrieved 2021-03-19.
  52. "新筑车站更名，请叫我"西安国际港站"！_腾讯新闻". new.qq.com. Retrieved 2021-03-19.
  53. "铁道部将加快东北地区铁路建设". news.sina.com.cn. Retrieved 2021-03-19.
  54. ""双层高箱"开启铁路运输新模式". pl.ifeng.com. Retrieved 2021-03-19.
  55. "Double-decker container train arrives at Mundra". April 18, 2009. Archived from the original on January 10, 2013.
  56. "Salient features". Dedicated Freight Corridor Corporation of India Ltd. Archived from the original on February 26, 2014. Retrieved April 5, 2014.
  57. UIC – International union of railways (2015-11-18), DFCCIL – Dedicated Freight Corridors Corporation of India Limited, retrieved 2017-08-01
  58. "Mombasa-Nairobi Standard Gauge Railway Project". Railway Technology. Retrieved 2019-02-09.
  59. Sanga, Benard. "SGR launches double-stack freight trains". The Standard (Kenya). Retrieved 2019-02-09.
  60. "The Betuweroute solution". April 1, 2004. Archived from the original on 2011-10-05. Retrieved July 22, 2011.
  61. "Video: Saudi Arabian Railways Dammam Bound Double Stack Container Freight Train". YouTube. 9 December 2012. Archived from the original on 2021-12-21.

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