Cartridge style load cell for web tension

[allscott]

So I've been handed a cartridge style load cell (Andantex 801.025.sc.1.25) that was purchased for a web tension project. I have never seen anything that looks like this before. This may sound like a stupid question but can someone tell me in what axis this thing actually measures force? From what I can tell from scouring the net these should be used on idler rolls and measure the axial force being placed on the rolls, is that correct? This is uncharted territory for me.

Thanks in advance.

 

[JRW]

These are very common. Yes, they are typically mounted on an idler roll.
So your doing a web line?

 

[widelto]

See attached file.

JRW:

I found this from carotron.com. It may help you.

 

[JRW]

widelto
I think you meant Allscott

 

[allscott]

These are very common. Yes, they are typically mounted on an idler roll.
So your doing a web line?

A very rudimentary one yes. I am paying off mylar tape that is being pulled into a machine, I need to control the tension on the payoff brake.

Unfortunately the mechanics started this project without consulting me. The transducer they bought won't work. The way they have designed this system I need a regular load cell like for a scale. The frame for the idler roll they designed will be pulled up to a fixed stop by the web. I need to calculate the force against the stop as feedback for tension. This is being fed to a controller that is controlling a magnetic brake on the payoff for the web.

I think what they designed will work they just bought the wrong type of transducer for the application which is why I was thrown for a loop.

 

[widelto]

jrw: yes sir, it was meant for Allcot, sorry.

 

[kamenges]

Originally posted by allscott:

The frame for the idler roll they designed will be pulled up to a fixed stop by the web. I need to calculate the force against the stop as feedback for tension.

What are you doing to make sure the idler roll frame doesn't hit the load cell like a hammer when it gets to the stop? Keep in mind that F=ma and "a" gets REALLY LARGE when you have metal to metal contact.

I guess I don't understand why you wouldn't use a cartridge style loadcell in this application. Also, load cells like this measure radial force. The design of the loadcell USUALLY measures force in the direction of the fixed collar (as opposed to the removable cap) but there should be an arrow on it indicating the force direction.

As an aside, Andantex looks to be a rebranded CMC loadcell. You may find more info on the CMC website.

Keith

 

[allscott]

What are you doing to make sure the idler roll frame doesn't hit the load cell like a hammer when it gets to the stop? Keep in mind that F=ma and "a" gets REALLY LARGE when you have metal to metal contact.

I guess I don't understand why you wouldn't use a cartridge style loadcell in this application. Also, load cells like this measure radial force. The design of the loadcell USUALLY measures force in the direction of the fixed collar (as opposed to the removable cap) but there should be an arrow on it indicating the force direction.

As an aside, Andantex looks to be a rebranded CMC loadcell. You may find more info on the CMC website.

Keith

Actually I had the mechanics down and we are going to modify the machine to use the cartridge style load cell. The reason I thought it wasn't going to work was because it woud be in the way of the web but we will just modify the frame a bit so that isn't an issue. And your right I had never thought about the arm banging against the load cell. The machine starts off fairly slowly so I don't think it would be a big issue but this is probably the proper way to do it any way.

Thanks for your help.