Force in lead screw to prevent rotation
Force in lead screw to prevent rotation
(OP)
Designing a lead screw. Usually we have a very strong guide that prevents the screw from rotating. But now we have a case with a weak guide and we were thinking about the necessary force to prevent it from rotating.
My assumption is: we need to lift 1000 kg with a 24 mm screw --> Necesary torque (aprox) =25 Nm
The force to prevent rotation (if friction factor stem-nut = 0,15) aprox 0,15·1000 =150 kg (or 4 N·m aplied at stem)
Am I the right way or I am over or under stimating the neccesary force?
Best regrads
My assumption is: we need to lift 1000 kg with a 24 mm screw --> Necesary torque (aprox) =25 Nm
The force to prevent rotation (if friction factor stem-nut = 0,15) aprox 0,15·1000 =150 kg (or 4 N·m aplied at stem)
Am I the right way or I am over or under stimating the neccesary force?
Best regrads





RE: Force in lead screw to prevent rotation
Are you talking about a thread with a lead angle that prevents rotation under load, or something else?
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JHG
RE: Force in lead screw to prevent rotation
RE: Force in lead screw to prevent rotation
Cheers
Greg Locock
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RE: Force in lead screw to prevent rotation
je suis charlie
RE: Force in lead screw to prevent rotation
RE: Force in lead screw to prevent rotation
The problem is that when the stems goes up it also has a tendency to rotate (is a secondary effect I guess due to friction). As usually the load has a strong guide we don't care about it. But we have a case were we'll have to hold this tendency to rotation with a pin. And now we're trying to guess what pin to use.
Hope this helps.
RE: Force in lead screw to prevent rotation
RE: Force in lead screw to prevent rotation
Now you can see my problem. If the residual torque is 15% I have 150 Nm which is a torque that needs some figures to be made.
Best regards,