Fluid coupling or torque limiter

[danyduclos]

Hi,

I am currently looking at a drive system wich broke due to a lock up.
Now my client wishes to have some sort of power limiter installed to be sure this won't happen again.
I originally had in mind to install a torque limiter, but then i got the info that the motor is a Nema D (275% starting torque) so i think it would disengage when starting up.
I am currently checking if a fluid coupling would do better.
We have someone looking over the electrical side of things, maybe a VFD would do the torque control...
Anyone has ideas or opinions on this?
Regards,
Dany

 

[dvd]

There should be a reason for the high starting torque. You should look over the drive calc's to see why. You have to design the drive system to transmit torque for start-up, normal operation and e-stop.

The Voith couplings are an interesting product.

http://www.voithturbo.com/safeset-safety-couplings.htm

 

[Artisi]

Did the drive fail during start-up or while in operation, if it failed during operation I would be investigating WHY as the first step?

Maybe the drive motor is capable of 275% during start but that doesn't mean it will be called upon to produce this torque if the driven machine doesn't require it- you need to expand your enquiry a little so we understand what you are asking.

 

[diskullman]

Some other options

http://www.ustsubaki.com/pdf/brochures/L0830000_Safcon.pdf

shock relay torque limiters

Russell Giuliano

 

[danyduclos]

The drive system failed when power wires were crossed and it went backwards, thus it was not able to move so the 275% torque did break a gearbox.
It shouldn't have happened in the first place if the guy would have checked the motor rotation but the client wants to make sure of it.
I asked for the electrical measurements to see how much power the system requires under operation, still waiting for it...

 

[MiketheEngineer]

You can't fix stupid - usually