Drop table
{{Short description|Device used in railway engine maintenance}}
{{distinguish|Official Table of Drops|Drop (SQL)|Drop-leaf table}}
{{Use dmy dates|date=December 2020}}
{{more citations needed|date=August 2010}}
File:Power-operated locomotive hoist, Battersea running shed (CJ Allen, Steel Highway, 1928).jpg, c. 1928.]]
File:Bettendorf truck at Illinois Railway Museum.JPG-style) freight bogie.]]
A drop table or wheel drop is a device used in railway engineering during maintenance jobs that require the removal of locomotive or rolling stock wheelsets.{{cite book|title=The Century dictionary and cyclopedia; a work of universal reference in all departments of knowledge|date=4 January 2024 |publisher=The Century Co|url=https://archive.org/stream/cu31924091890602#page/n13/mode/1up}} The machine is built in a drop pit allowing a locomotive or rolling stock to be rolled onto it, avoiding the need for heavy cranes or jacks to lift the vehicle off the rails.
The vehicle is placed over the drop table, and the connections attaching the wheelset to the vehicle are unfastened. This allows the wheel set to 'float' independently of the locomotive. The wheelset is lowered into the drop pit on a short section of rail, and a dummy rail, normally a part of the drop table machinery, is then inserted in the gap over the lowered wheelset. This enables the vehicle to be moved clear of the drop table on its remaining wheels, so that the removed wheelset can then be lifted out of the drop pit for maintenance work to be performed on it.
References
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External links
{{ external media
| float = right
| image1 = [https://archive.org/stream/railwaymechanica95newy#page/678/mode/1up/search/african A drop pit and simple drop table in use in South Africa in the early 20th century]
| image2 = [https://archive.org/stream/railwaylocomotiv37newy#page/134/mode/1up/search/drop Drop pit and Drop table at Acca, Virginia, USA in the mid 1920s]
}}
- [https://web.archive.org/web/20081223223949/http://www.watercressline.co.uk/tw/pages/whldrop.htm An example of a wheeldrop in use (with photos and web-movies)]