美国人讨论摩擦系数的贴子:
proejuan (Mechanical) 8 Feb 07 9:47
What is the coefficient of friction for calculate the pull force in a rail car?
civilperson (Structural) 8 Feb 07 10:55
Steel on steel ranges from: High of 0.78 to Low of 0.05. Use of sand box required on slippery surfaces such as leaves, oil, & ice. Use 0.25 for design purposes, (2% maximum grade).
wiktor (Structural) 14 Feb 07 15:41
Typically 0.005 i.e 5 lbs per 1000 lbs.You can find more details here:
https://atiam.train.army.mil/soldierPortal/atia/adlsc/view/public/7489-1/fm/4-01.41/chap10.htm#tab10-1
harrisj (Automotive) 8 Mar 07 10:38
At a mu of .005, a 100-ton locomotive will achieve a drawbar pull of 1000 lbf. That's not much of a train.
The loco won't even make it up a 0.5% grade on its own, let alone pull anything else up it.
Something wrong here. Civilperson's numbers look more realistic, although I've never come across as high as 0.78 before.
civilperson (Structural) 8 Mar 07 11:29
Two different questions have been answered in the above postings. The rolling resistance of a towed rail car is given as an average by witkor, the tractive effort as a drawbar pull by a locomotive is given by civilperson and harrisj. The Army Manual cited by witkor has both answers. The STE, (starting tractive effort), is given as 0.3 to 0.2 with .25 as a design value and the CTE,(continuous tractive effort), is half of the STE.
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