Your articles on containerboard values in the last two issues of Box Score are helpful. We are gathering this type of information so that we can analyze and improve the material handling equipment that we manufacture.

 

Do you have information on tensile strength of linerboard for various basis weights (MD and/or CD)?  Do you know if there a direct mathematical relationship between tensile strength and Mullen burst test values or are there other factors that need to be considered? Thank You.

 

 

Here is some good information on MD Tensile Strengths of linerboard.  This is a European perspective as US mills are not likely to use this  test procedure as a specification or even to report test result to convertors.  Please note that yes, the values differ by basis weight and recovered fibre content.  That is to say that machine direction tension is directly proportional to the amount of virgin long fibre in the sheet.  Metric values have been converted to US units.  The US has no containerboard strength grading system as do the Europeans.  I can fill you in on the details of the difference in a separate e mail if you want to go that deep.

 

Test liner 1 is typically about 15% below US Mullen and compression; Test liner 2 is typically about 25% below: and,  and Test liner 3 is typically about 40% below.

 

MD Tensile Strength in lb-f/in

BASIS WEIGHT #/MSF	‘VIRGIN” KRAFT	TEST LINER 1	TEST LINER 2	TEST LINER 3
20.5	61.7			37.1
22.5				39.4
23.5	70.2			39.4
24.6		62.9		41.7
25.7	75.4			48
27.7	80.6			46.3
29.7		71.4
30.7	97.1
34.8	97.1			58.8
35.8		80
38.9				62.9
41	118.3	85.7
45				66.9