Onward (locomotive)
The Onward steam locomotive was a bad design because of its polygonal drive wheels. It was built in 1887 by the Hinkley Locomotive Works in Boston for the Swinerton Locomotive Driving Wheel Company .
history
Hinkley Locomotive Works in Boston delivered the unusual locomotive in 1887 to the Swinerton Locomotive Driving Wheel Company in the USA, which expectantly christened it Onward . Its unique feature was that it had non-circular, polygonal drive wheels. The company's founder, CE Swinerton , had specified that both drive wheels should be regular 118-square polygons with as many edges, each with an edge length of 2 inches (50.8 mm). He wanted to show that a line contact at the intersections produces better adhesion than the point contact of a circular wheel. However, this was not the case, as even steel deforms itself under high pressure in such a way that a round wheel also generates surface pressure.
The type 2'A1 ' locomotive had only one drive wheel set . This design has long been unusual elsewhere because it has poor adhesion, but was probably chosen here to demonstrate the supposed advantages of the non-round wheels more clearly. The Onward was tested on several railway lines in the north-east of the USA, but showed no advantages, especially because of the enormous vibrations and wear, so that railroaders with practical experience could not be convinced.
The locomotive was sold to the Portland and Rochester Railroad after the polygonal wheels were replaced with conventional round ones. A few years after the purchase, P&R sent the locomotive to the Manchester Locomotive Works to have it converted to the standard 2'B wheel arrangement. It was scrapped in 1905.
Web links
Individual evidence
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^ Thinking Outside the Circle: A Locomotive with Non-Circular Wheels . ( Memento of the original from June 30, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. tracks.lionel.com, April 11, 2015. New Type of Locomotive Driving Wheels . In: Scientific American (Munn & Company), March 8, 1890, pp. 145–146 (English)
- ^ A b c Douglas Self: Locomotives with Non-Circular Wheels . The Museum of Retro Technology on douglas-self.com, November 8, 2005, version from March 1, 2011 (English)
