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).
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.
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.
