motorquest
Mechanical
- Apr 11, 2005
- 3
Hello,
I'm building a motorized platform that will weight approx. 1500 lbs and will be used to move a load weighing ~32,000 lbs. I plan to use six 12" Dia. x 4" tread polyurethane on steel wheels. The surface is level, smooth concrete. I need to find the locked rotor torque necessary to overcome static friction in order to select the correct gearmotor.
According to my calculations I would need a force of 33,500 N (7520 lbs) to overcome friction and start the load moving (Coef. S-friction used = 1.0) without wheels. My question is, how do I determine the force required to start the load "rolling"? I've pulled every mechanical engineering and physics text that I can find but I'm overlooking something.
One engineer at a caster manufacturer told me that I could use 5% of the total load (33,500 #) as a guideline for selecting the gearmotor.
Am I anywhere near the mark on either count?
MotorQuest
I'm building a motorized platform that will weight approx. 1500 lbs and will be used to move a load weighing ~32,000 lbs. I plan to use six 12" Dia. x 4" tread polyurethane on steel wheels. The surface is level, smooth concrete. I need to find the locked rotor torque necessary to overcome static friction in order to select the correct gearmotor.
According to my calculations I would need a force of 33,500 N (7520 lbs) to overcome friction and start the load moving (Coef. S-friction used = 1.0) without wheels. My question is, how do I determine the force required to start the load "rolling"? I've pulled every mechanical engineering and physics text that I can find but I'm overlooking something.
One engineer at a caster manufacturer told me that I could use 5% of the total load (33,500 #) as a guideline for selecting the gearmotor.
Am I anywhere near the mark on either count?
MotorQuest