Boxpok
A Boxpok is a steam locomotive wheel that gains its strength through being made of a number of box sections rather than having traditional solid spokes (the name is a variation on "box-spoke"). Being hollow, they allow better counterbalancing than conventional drivers, which is important for fast locomotives. The Boxpok wheel was patented by General Steel Castings Corporation of Granite City, Illinois.
![](../I/Roues_Boxpok_141-R-1199.jpg.webp)
Other wheels
The Boxpok was the most common of the four disk wheels in use by US steam locomotive designers, the others being the Baldwin and Scullin. A fourth design, the Universal, was used in locomotive rebuilds. All vary slightly in appearance but are essentially the same in structure.[1]
The term "Boxpok" is also sometimes used to describe the Bulleid Firth Brown (BFB) wheel in use on British railways at that time, but this is incorrect; while the BFB is similar to the Boxpok, one side of each box section is left open, so is not a true box structure unlike the Baldwin, Boxpok and Scullin drivers.
See also
References
- Lamb (2003), p. 180.
- Lamb, J Parker (2003). Perfecting the American Steam Locomotive. Indiana University Press. ISBN 0253342198.CS1 maint: ref=harv (link)
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