Calculating Torque Needed to Roll 9000lb Roll Across Floor

[scampbel]

I need to roll a 9000lb roll across the ground. It is 4.5 feet in diameter, and is 115 feet long. I am attaching the bold ends to apply torque to move it. I don't need to move it that fast. How much Torque would I have to apply to each end to roll this across a flat floor. Assume that all torque applied is used to roll the drum and nothing else slips or moves. I have a number, I am trying to determine if it is correct. I am coming up with roughly 158 lb/ft per end. Any help is greatly appreciated.

Thanks!
Steve Campbell

 

[FredGarvin]

It's the basic

$$\Sigma{T} = I \alpha$$

Set your desired acceleration and calculate the required torque from that. That will be a higher number than the torque required to simply overcome friction to maintain a constant speed.

 

[minger]

If he assumes constant velocity, then there is no acceleration though, and theoretically the needed torque would be zero. However, one of the main friction forces is from the body deforming.

I remember back from machine design that there are formulas to calculate deflection of spheres and cylinders based on various material parameters. But, even based on a known deformation, I'm not quite sure how to convert that to a friction coefficient.