- Bethungra Spiral
The Bethungra Spiral is a rail spiral, built on the Main South railway line of
New South Wales inAustralia at Bethungra to ease the gradients when the line was duplicated between 1941 and 1946. Bethungra is between Cootamundra and Junee.The original line was graded at 1 in 40 for
Sydney bound trains, which imposed a severe limitation on train loads, and also caused congestion asbank engine s were attached. The spiral makes use of local geography in the shape of a convenient hill which the uphill line spirals around. Two short tunnels are required. The spiral increases the distance travelled by uphill trains by about 2km. Downhill trains continue to use the original line. The ruling gradient of the new uphill line is now 1 in 66, compensated for curvature.The
CountryLink XPT passenger train from Melbourne Southern Cross to Sydney Central uses the spiral while the train from Sydney to Melbourne uses the original line.References
* cite web
url=http://www.heritage.gov.au/cgi-bin/ahpi/record.pl?NSW5011929
title=Bethungra Spiral
work=NSW Heritage Register (ref 5011929)
publisher=www.heritage.gov.au
accessdate=2008-08-13External links
* [http://www.fallingrain.com/world/AS/2/Bethungra.html Elevation = 432m]
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