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Test for continuous torque and peak torque.

  1. Jan 3, 2012 #1

    I want to test gearboxes.
    How do you recommend I test the continuous torque of a gearbox and also the peak torque of the gearbox?
    I want to test to see the maximum torque the gearbox can handle.
    How do you suggest I go about doing so?
    What type of equipments or measuring devices would I need in order to measure this limit?
    There are two things I want to test for, peak torque - the maximum torque the gearbox can handle and continuous torque - the continuous torque applied to the gearbox and see when it will fail.
    I have one last question, what would you consider as failing in case of tests like these?
    Please let me know if you guys need any clarification.
    Thanks so much for your time.
    Last edited: Jan 3, 2012
  2. jcsd
  3. Jan 3, 2012 #2
    First gear is almost always the weakest part of the gearbox so testing the amount of torque the transmission will take in first before shredding some teeth would be the peak torque test. Failure mode is shearing of the involved parts and isn't dependent on rotational speed so can be essentially a static test. That can be accomplished with a large torque wrench applied to the input shaft.

    The durability test at high load is more a test of how well the shafts are supported by the bearings.
  4. Jan 3, 2012 #3
    Impact torque can be a factor as well, if the box may be subjected to hard engagement loadings, etc. A tooth that can withstand a static load may break on impact for example. The ductility/brittleness of the gears can come into play.

    The environment the box might be used in could be dusty, or damp, or freezing, or hot, etc. This will potentially impact the above factors, as well as the chosen lubricants, bearings, races, and susceptibility of meshing factors to grit damage, etc.

    So, testing a box can involve any number of parameters, depending upon what you want the box to be able to stand up to. Everything Mender said is dead on too. You might want to think about it all.
  5. Jan 9, 2012 #4
    Thank you mender, I was thinking the same thing about the peak torque value.
    It's feels better knowing some one else also thinks the same.
    And as for the parameters and conditions, I should've clarified.
    My questions are for a step motor and it's planetary gearbox, not an ICE and it's sequential gears.

    These planetary gearboxes have 3 gears surrounding it's motor's shaft gear.
    Something like that. ^

    The middle gear is coupled onto the shaft of the motor, while the other three on the outside is part of the gear box.

    All other factors can be ignored since this is being conducted inside a controlled environment.

    Any help would be greatly appreciated.
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