Recent content by sallama

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    What is the critical speed of the hollow shaft and how can it be increased?

    And is there any solution for rotating hollow shaft. Not for the non rotate center shaft
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    What is the critical speed of the hollow shaft and how can it be increased?

    From your answers, I should apply some solutions... -inner shaft will be lighter with decreasing diameter between bearings. Or machine shaft to cross shape between bearings? will this be effect worst fatigue life in the future?? -Is there a good choice to apply heat treatment to get harder...
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    What is the critical speed of the hollow shaft and how can it be increased?

    Yes, you are right. Center shaft doesn't rotate.Center Shaft only for fixing and bearings mounted on it. This was done because I have limited hollow shaft material/tube (Length & Diameter is limited per my design so that I should use inner shaft for unbalance and fix). I can not change design...
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    What is the critical speed of the hollow shaft and how can it be increased?

    Thanks AlephZero, What is your advice to increase this critical speed to 90-95 Hz without new production. Because i want to run the hollow shaft with half of the critical speed, and this will be 2500x2=5000 RPM. But above 4000 RPM will be enough. Where and which sizes can l add mass to the...
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    What is the critical speed of the hollow shaft and how can it be increased?

    I want to figure out critical speed of hollow shaft. When I calculate from equation, critical speed of this shaft is approximately 10000 RPM. But when I start to increase speed of shaft, at ~2500 RPM I see that the critical speed occured. What can I do to increase this critical speed to double...
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