- February 21, 2012, Timothy J. Walker
WebHandlersQuiz1: Tension Control - How do you determine the target web handling tension for a give product in units of force or force per width?
Answer to WHQuiz#1:
Test your web in a tensile elongation tester per ASTM D638 or ISO 527. Find the force per width tension that damages your product, either yielding (for ductile materials) or breaking (for brittle materials).
Set you average tension to 10-20% of the level that damages your product. If you know you have modest machine or crossweb direction tension variations from roller variations, web bagginess (especially if you web is narrow), misaligned splices, and roller drag / inertia, then you can run with less safety factor, if needed.
More on this topic was covered in this archived Web Lines column:
What Is the Right Tension? (Dec. 2009)
If you missed it, here are all 20 questions in my Web Handler's Quiz.