Railway turntable
[1][2] It is especially used in areas where economic considerations or a lack of sufficient space have served to weigh against the construction of a turnaround wye.
When a diesel locomotive is operated as a single unit, the railway company often prefers, or requires, that it be run "front end" first.
Turntables were also used to turn observation cars so that their windowed lounge ends faced toward the rear of the train.
Early wagonways were industrial railways for transporting goods—initially bulky and heavy items, particularly mined stone, ores and coal—from one point to another, most often to a dockside to be loaded onto ships.
As steam locomotives replaced horses as the preferred means of power, they became optimised to run in only one direction for operational ease and to provide some weather protection.
[4] The resulting need to turn heavy locomotives required an engineering upgrade to the existing turnplate technology.
This was most often achieved by a steel rail running around the floor of the pit that supported the ends of the bridge when a locomotive entered or exited.
The turntables had a positive locking mechanism to prevent undesired rotation and to align the bridge rails with the exit track.
[12] The Israel Railway Museum, Haifa, has a turntable made by Metropolitan Carriage, Wagon & Finance Company, Old Park Works, Wednesbury.
It was found buried in the grounds of the Israel Defense Forces History Museum, on the site of the old Jaffa railway station yard.
Most were situated at the major railway yards like Kandy, Galle, Nanu Oya, Anuradhapura, Maho, Galoya, Trincomalee, Batticaloa, Polgahawela Jnc, Badulla, Puttulam, and Bandarawela and depots in Dematagoda 2no.
Several working examples remain, many on heritage railways in Great Britain, and also in the United States.
[15] In that case, a six-year-old child was playing on the unguarded, unfenced turntable when his friends began turning it.
The Nebraska Supreme Court held that the railroad company may have been liable for negligence after considering the "character and location of the premises, the purpose for which they are used, the probability of injury therefrom, the precautions necessary to prevent such injury, and the relations such precautions bear to the beneficial use of the premises."
[18][19] On rare occasions, a turntable would spin too fast during high winds, as happened at Garsdale (Settle–Carlisle line) in the UK c.1900.
