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Stresses and forces

  1. Apr 7, 2014 #1
    1. The problem statement, all variables and given/known data
    https://dl.dropboxusercontent.com/u/11241083/tractor.png [Broken]
    How do I calculate reaction forces at A and B? We pull with a force F2 = 300 N on the steel wire. The steel wire goes two and a half times around the axel wheel.

    [itex]d = 38 mm[/itex]

    [itex]D = 200 mm[/itex]

    [itex]a = 100 mm[/itex]

    [itex]b = 120 mm[/itex]

    [itex]\sigma_{w} = 256 \frac{N}{mm^{2}}[/itex]

    [itex]K_{t} = 1.5[/itex]

    [itex]\eta_{k}=0.7[/itex]

    [itex]\mu=0.2[/itex]

    Correct answers:
    [itex]F_{A} = 13.3 kN[/itex]
    [itex]F_{B} = 6 kN[/itex]
     
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Apr 7, 2014 #2

    SteamKing

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    What have you tried? This seems to be a very straight forward problem.

    Why don't you try something that can be checked and discussed?

    Hint: Pretend the power take of shaft (a-b-d) is a beam with two supports and the load from the sheave is cantilevered over the end of this beam.
     
  4. Apr 7, 2014 #3
    What is the force at the end of the shaft? Is it the same as F2=300N? I sum moment at point B to try to find reaction force at A.
    https://dl.dropboxusercontent.com/u/11241083/New%20Document20140407191616593.pdf [Broken]
     
    Last edited by a moderator: May 6, 2017
  5. Apr 7, 2014 #4

    SteamKing

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    Look at the left figure, the one showing how the line goes around the sheave. You are given F2, so make a FBD of the sheave to see what load the shaft sees.
     
    Last edited by a moderator: May 6, 2017
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