# Drive Chain Connection

1. May 24, 2015

### George Zucas

Hello all,

I have two rollers that will be rotated which will in turn rotate another tube on top of them. The connection will be made with a drive chain between the motor sprocket and the roller sprocket(s). My question is, would it be better to connect the chain to one roller, or to both?

I'd think that since the work to be done is the same in both cases (rotating the tube), there shouldn't be any difference in terms of power consumption and it would provide extra stability. May there be any other thing to consider?

Oh wait, I actually found a similar setup, though I am not sure how the chain system at the beginning works. It looks like there are two sprockets on the motor shaft and two different chains are used, but can't be sure.

My main problem is that what I've learned in school and all the information I can find about chains are for two sprockets. I made all the necessary calculations for a two sprocket setup but don't know what would happen if three sprockets are used.

Thank you for any help.

2. May 29, 2015

### Greg Bernhardt

Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?

3. Jun 2, 2015

### Staff: Mentor

What is the coefficient of friction between the tube on top and the rollers? Is it high enough to be sure that the tube will turn the 2nd roller when it is not actively being driven?

4. Jun 3, 2015

### George Zucas

The rollers will be steel and the tube is also steel but it is very hot (like 750 C degrees or so). Their surface are not very smooth so I believe the coefficient of friction will be high enough. I took it as 0.05 in my power requirement calculation as I was advised, but the information about this is sparse.

Last edited: Jun 3, 2015
5. Jun 3, 2015

### Staff: Mentor

What would be the ramifications if the 2nd roller stalled due to a low coefficient of friction? Would that hurt the process at all?

6. Jun 3, 2015

### George Zucas

You mean the tube keeps rotating but one of the rollers just stop? As long as the tube keeps rotating it is not a problem. They are being transferred in the facility and they need to be constantly rotating in the process.

7. Jun 3, 2015

### Randy Beikmann

You need to consider what force/torque may act to oppose the rotation of the tube (the work piece). This is what could cause slippage. From this you can either design the system so that the normal force on the driven roller is increased (for more traction) by the opposing torque, or perhaps drive both rollers.
It would be simpler to drive a single roller if possible. Simplicity is good!

8. Jun 4, 2015

### George Zucas

Thanks. I am sure there wouldn't be any problem like that because the tubes will be really heavy (something like 20 tons per piece) So driving a single roller would be better solely because it is easier to implement? If there would be no change in energy consumption or some other factor ( in my opinion there shouldn't be, but I didn't want to act on a guess) it is good either way.

9. Jun 4, 2015

### Randy Beikmann

I'm not saying to use a single roller "solely because it is easier." What I mean is that if there's no reason to make it complicated, then keep it simple. If a single roller meets all your requirements (like providing enough traction), why use two? If you find a need for two, or just feel more confident in it, then that's what you do.