Dar wrote:
Now I have a 1/2 hp , 247 in. lb torque, ac gearmotor that bogs down
under
the loads I need it for , and I need a bigger motor. I found another
1/2 hp motor
that has 487 in lbs , but am not certain that the higher torque
rating alone is
enough. So the question is : what is the relationship between hp,
torque, and actual
ability to perform high-load operations ?. This is (to be) set up
powering a rolling mill.
It was suggested that I get a .75 or 1 hp motor , but...

thanks,
Dar

Dar

You need to know how much torque is necessary to drive your load, and
how fast you want it to rotate. Add some torque margin (like 50%) and
then pick a gear motor with matching specs.

Measure how much torque it takes to crank your mill with the heaviest
load you expect to use.

Ignoring gear efficiency losses hp = (RPM * torque_in*lb) / (5252*12)

I calculated the efficiency on one gear motor listing as 69%, others may
vary.

CarlBoyd