Road trailer
A roadrailer is a semi- trailer that can be placed directly between two special bogies and thus connected to a trailer train. The road trailer is used for transport in combined traffic .
Compared to the rolling road and similar piggyback traffic , the flat wagons are saved , but special semi-trailers are required . Because of the tensile and impact forces that can be heard in rail traffic, the semi-trailers must be particularly reinforced and also carry the equipment required for rail traffic as an additional load in road traffic.
The advantages of the road trailer lie in the higher number of transport units that can be loaded with a given train length and the high payload of 68% of the total weight compared to 51% for containers on freight wagons and 45% for rolling country roads. Due to the narrow gaps between the road trailer units, as a closed train composition, it offers very low air resistance compared to the RoLa and container trains .
This is offset by the disadvantages of the semi-trailer's slightly higher purchase price and its approx. 360 kg increased weight, which reduces the possible payload. Furthermore, the concept with swap bodies and the widespread ISO containers has strong competition. In the case of the latter, a transport vessel can simply be lifted out of the train by means of appropriate loading devices due to the flat wagon being separated from the transport vessel. With the roadrailer , the train composition would have to be separated, the semi-trailer and bogie removed from the track and finally the train composition reunited.
history
The first Roadrailer came in the 1950s in the United States and had a permanently mounted rail truck , which was lowered in rail transport. It was later removable in order to be able to carry more payload on the road and at the same time acted as a support point for the next trailer. In the USA today special bogies are used .
They were also used in the UK in the early 1960s and in Australia by the Australian National Railways Commission in the 1980s and 1990s .
1999 opened Bavarian Trailerzug company mbH (BTZ) a Roadrailer -Pendelverkehr of Soltau -Harber to Italy . After a good two years, however, BTZ shared the fate of many other start-ups and went bankrupt. The German road trailers had two-axle rail chassis, in the USA single-axle was sufficient due to the axle loads permitted there.
In the USA they are mostly used in block trains . The most important provider of road trailers is the Norfolk Southern subsidiary “Triple Crown Services” . By Amtrak took place at times of use as postal and Expressgutwagen at the end of passenger trains . Some Roadrailer consist of individual cars with standard coupling for the beginning and end of the trailer and can be adjusted in a train with different trailers, whereas the front and the top of the rear trailer are on a cart in other designs the end. These are used by means of adapters in separate trains or at the end of regular trains.
Triple Crown Services has offered road trailer services since 1986 , all but one of which were discontinued in late 2015.
Web links
Individual evidence
- ↑ Traffic: Punitive tariffs for clever people . In: Der Spiegel . No. 24 , 1996, pp. 176 f . ( Online - June 10, 1996 ).
- ↑ Equipment - Triple Crown ( Memento from June 27, 2011 in the Internet Archive )
- ↑ When did things happen on British Railways after Nationalization? - Chronology for British Railways 1947-2002 ( Memento of October 26, 2008 in the Internet Archive )
- ↑ Railways and Unit Loads - Modern Rail Container Services:
- ↑ Rainer Mertel: Why didn't “bimodal” become anything? , DVZ, October 15, 2015