I have been looking at a lot of old railroad photos from the early part of the 20th Century. I noticed on some of the rail disaster photos from that era that the wheels on the rolling stock were made with a swirly design on the inside face of the wheel (the side facing the axle inboard). Why were the wheels made this way? Thanks. TonyM.
Cooling fins , in in the days of cast iron shoes , retainer valves and no dynamic brakes , the wheel got really hot .
Turns out those fins were stress risers and made the wheels more likely to crack - even more than the benefit provided from extra cooling - so the practice was dropped.
Randy and Oltmannd,
Thanks for the reply.
Tony M.
Here’s a link to an interesting article on this titled “Railroad Car Wheel Usage in the U.S.”: Note that the introductory paragraphs state:
“The following information was printed in the third quarter 1996 issue of the Central Headlight, the newsletter of the New York Central System Historical Society. It was published in the form of an answer in the Tack Board, a general research question and answer column. The column is edited by Bob Cosgrove, who has been very active in the Society for many years, and this answer is the result of his research.”
“The answer is reproduced here with his permission; any further citation or reproduction should be done only with his expressed permission (see the address at the end of the article). The information here is (c) 1996 the NYCSHS.”
http://www.vbfamily.com/Wheeldoc.htm
A more plausible explanation of the purpose of the “swirly design” - apparently more properly known as “brackets” - as well as the details of why that is no longer used, is in the 4th paragraph under the heading “The Decline of Cast Iron Wheels”, at about 2/3 of the way down/ through this web page.
Hope this answers your question.
- Paul North.
Paul,
Thnaks for the great link!!! Incredibly interesting.
TonyM.
I had always assumed that they were casting runners or vents to reduce voids. That’s what I get for assuming. Thanks for the info.
dd
I know of two basic types of cast iron wheels with the spiral ribs on the back. One type was a solid wheel, and the other type was hollow in the bulky mass surrounding the axle. On that wheel, the casting was cored out in the mass around the axle, and there were three holes piercing the wall on the backside of the wheel where mold sand could support the mold core that made the hollow. The three holes were about 1-1/2” diameter, arrayed in a radial pattern around the hub. The purpose of the hollowed out section was to create a spread-out, double wall in the highest stress area where the wheel met the hub. The spiral ribs were applied to the back of this hollow hub wheel and looked similar to the ribs on the solid wheels.
This wheel with the hollowed hub was the Washburn pattern wheel, invented in 1850, which became the industry standard by 1890. In my opinion, this was the handsomest car wheel ever produced. This wheel and several others are discussed in John White’s book, The American Railroad Freight Car. Like the source provided by Paul North above, Mr. White references the ribs as being provided for strengthening or reinforcement, and also to prevent stress cracking during post casting cooling. In both s