Tension calculation formula

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Re: Tension calculation formula

Postby jmhorwitz » Tue Jun 11, 2013 3:53 pm

great, thanks!!!
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Re: Tension calculation formula

Postby Frank Burgos » Wed Jun 12, 2013 6:03 am

Hi JM,

I sent you two calculators. I don't know what stage of development they're in, so have a look at them and let me know if you need any adjustments.

Best regards,
Frank
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Re: Tension calculation formula

Postby flexouk » Fri Jun 14, 2013 1:23 pm

Running presses with a closed loop tension system I always use a PLI chart. Each material should have a PLI rating. I then take the PLI of the material then times it by the web width. The exit tension is then normally plus 10 pounds. The material manufacturer should be able to provide the materials PLI
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Re: Tension calculation formula

Postby Injinnius » Fri Jun 28, 2013 1:54 am

Obviously, not everyone will agree on the correct method of setting tension. There's a wide variety of information available online.
Many years ago, while working for a major press manufacturer, I came across 2 charts for recommended tension; one was for tag stock, one was for label stock.
I took the data points from those charts, entered them into MathCAD, and ran a linear regression ... to find an equation for a line that would fit that chart.
Both charts returned the same equation:
Thickness of the material (in mils), divided by 3, times the width of the material (in inches) = recommended tension (in pounds)
I'm a tech, not a pressman ... but I've recommended that equation to a lot of people over the years, and it seems to work well in most cases.
One note: many of the press operators I've worked with over the years are confused about nip roll pressures. It's important to remember that in most cases the nip roll is, in fact, an idle roller. Increasing the pressure does NOT increase the paper tension. However, running too light a nip roll pressure does not allow the nip roll to grip the paper firmly enough to have control of the tension, and leads to registry problems.
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Re: Tension calculation formula

Postby Frank Burgos » Fri Jun 28, 2013 8:45 am

Thanks Injinnius. Great information. When I get a little free-time, I may incorporate it into a calculator.

Frank
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Re: Tension calculation formula

Postby Gorilla Printer » Mon Jul 01, 2013 5:42 am

Can I be first on your list Frank? :smile:

And thanks for the formula Injinnius.

Cheers
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Re: Tension calculation formula

Postby Frank Burgos » Mon Jul 01, 2013 8:08 am

Sure. Have a great day, guys!
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Re: Tension calculation formula

Postby Donovan » Mon Apr 20, 2015 2:19 am

Hi Frank
I know it`s a couple of years down the line but if you are able to send me the article on tension control and the calculator. I would appreciate it. I am also especially interested in the setting of the taper control.
Thanks
Donovan
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Re: Tension calculation formula

Postby Frank Burgos » Wed Apr 22, 2015 11:48 am

Hi Donovan,

I don't recall getting the article, but I will send you the same two calculators I mention elsewhere in this thread. I haven't scrutinized them, lately, to see how they compare to some of the formulas suggested here, but you're welcome to them. Just consider them "as-is."

Regards,
Frank
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Re: Tension calculation formula

Postby FlexCoor » Tue Jun 16, 2015 1:34 pm

Hi Frank,

Is it still possible to recieve the two calculators mentioned in this thread? Have you sent these through trial? Do you have a resource for lamination tensions?

Thanks!
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Re: Tension calculation formula

Postby wilsontim » Mon Nov 02, 2015 2:54 pm

Good afternoon all At KICTEAM in auburn Maine, we are using a mark Andy press P3 we are new to the printing world ,we are printing on foil , we multiple the width of material by 4 that would be the starting tension and the ending tension would be the width of the film we are running, not sure if that would work on most material
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Re: Tension calculation formula

Postby gricey » Mon Nov 23, 2015 6:37 pm

Hi Frank
I have a challenge for you. I have a SVK board press which was brought into us by Tutankhamen's grandad :smile: . We are having lots of problems with tensions, It's an old film press that has been converted to high grammage/ caliper board. Unfortunately the manual we have is very elusive (most of it is in hieroglyphics :smile: ) Do you have any advice that can help us to try and control these tension issues.
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Re: Tension calculation formula

Postby bloss22 » Tue Jan 05, 2016 6:17 pm

Frank,

Could you send me your calculator as well?

Thanks!
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Re: Tension calculation formula

Postby flexolover » Thu Jul 28, 2016 12:45 am

Hi Frank,
Could you pls share the calculator to me ?? :smile:
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Re: Tension calculation formula

Postby longtimefan » Tue Aug 09, 2016 2:33 am

gricey wrote:Hi Frank
I have a challenge for you. I have a SVK board press which was brought into us by Tutankhamen's grandad :smile: . We are having lots of problems with tensions, It's an old film press that has been converted to high grammage/ caliper board. Unfortunately the manual we have is very elusive (most of it is in hieroglyphics :smile: ) Do you have any advice that can help us to try and control these tension issues.


Know this is old...

But if it was an old film press and now you paper... Are ALL your idler rollers big circumferences ones... Or ones around 3 to get inches in circumferences
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