Dave –
Here is the additional information I promised. Following is a link to the AICC’S electronic BoxScore library.
http://www.aiccbox.org/boxscore/09_Mar_Apr.pdf
In this March/April 2009 go to pages 19-21 and review the chart and article. Click here for another chart showing different basis weight combinations and their expected ECT values. Historically corrugators have varied by as much as 40% in their ability to obtain a predicted ECT target from the ring crush values of the components. And, convertors can also destroy as much as 40% of the incoming ECT strength in their operations.
Check our other resources in our on-line store through the website. We have been developing many materials in the last few years to address concerns just like the one you have asked.
-Ralph
Dave asks:
I have a question about so called “high performance” linerboard. I had a local corrugator inform me that they were running a 32ect sheet with two 29 lb. high performance liners. What do the mills do or add to make liner board “high performance? Additional fibre, the way they arrange the fibers, chemical additives? Or is it just the combination with a stronger medium that allows them to say the liner is high-performance?
Yes, all those elements can contribute to “stronger” containerboard and combined board. Much has to do with corrugator and converting efficiencies. We have many resources and presentations to shed light on these issues.
What you need at the converting end is an incoming ECT of 38 or 39 to stamp a 32 on the box. Yes, it is possible to achieve the necessary levels off the corrugator with a substantial medium like a ‘Power Flute’ fluting. You need a certification from your supplier that they are able to engineer a corrugated structure that meets the minimum requirements you need.
Please feel free to contact me again if this not completely answer your question
-Ralph
askralph 