SCA Containerboard’s commitment to quality is backed up by reliable testing and analysis. Testing is conducted according to recognised industry standards at each mill and at the state-of-the-art SCA Research & Development Centre.
Commitment to quality must be supported adequately by serious and reliable testing and analysis. Isolated measurements are not sufficient to detect problems in time. Only with continuous measurement can high-quality paper performance be assured. That is why each of our mills is furnished with the most modern equipment for process and paper testing, with dedicated staff present 24 hours a day. In addition, the SCA R&D Centre, one of the most modern and efficient in the paper industry, can back up the mill laboratories for any special test that might be required.
Round Robin test
Testing climate
Common properties and methods
- Mechanical properties
- Surface properties
- Other properties
- Special properties
- Corrugated properties
Round Robin test
In order to maintain all standard testing at an accurate level, our R&D Centre participates in three Round Robin tests organised by STFI, CEPI and StoraEnso. All liner and fluting properties are tested four times per year and corrugated properties are tested twice per year. For the most common properties there are about 100 participants in the StoraEnso Round Robin. Our R&D Centre performs well in all three Round Robin tests and any inaccuracy is immediately corrected. All our containerboard mills also participate in the StoraEnso Round Robin.
(See table Round Robin Matrix.)
Testing climate
It is important to have a well-defined testing climate to ensure the reliability and repeatability of the different tests. The liners and flutings are moisture sensitive and their strength and stiffness properties are dependent on the ambient temperature and relative humidity. Small changes in the moisture content of the sheet affect the paper properties considerably. The standard testing climate is 23°C and 50% relative humidity (RH). Before testing, the sheets are pre-conditioned at 30% RH for 24 hours, and then conditioned in the testing climate according to ISO 187. Testing at high RH is also performed, especially for wet strength liner and other liner and fluting grades for use in humid conditions. For lifetime testing, humidity is cycled between 30% and 90% RH several times.
In general, compression strength properties are very sensitive to moisture variation. For example, if the moisture content of the material is increased by 1% the compression strength decreases by approximately 8%. A 1% change in the material’s moisture content is associated with a change in relative humidity from about 50% to 60%.
Common properties and methods
Find here a selection of our tests, methods and related procedures. Infrequently used methods are not mentioned. We also develop new methods when needed. One example is the lifetime measurements.
Mechanical properties
- Bursting strength
- Short Span Compression Test, SCT
- Ring Crush Test, RCT
- Tensile strength and stiffness
- Z-strength
- Scott Bond (Ply Bond)
- Concora Medium Test, CMT
- Corrugated Crush Test, CCT
- Bending resistance
- Fracture toughness
Surface properties
- Roughness PPS
- Roughness Bendtsen
- Brightness and colour
- Friction
- Dennison
- Taber
- Cobb
- Optical Profile Tester, OPT
Other properties
- Basis weight
- Caliper
- Moisture
- Ash content
- Fibre orientation
- Formation
- Air Permeance Gurley
- Air Permeance Bendtsen
Special properties
- Hygro expansion
- Creep measurements
- Cracking
- Z-toughness, DCB
- Flexo printing
- Tapio
- TSO tester
Corrugated properties
- Box Compression Test, BCT
- Sagging
- Corner compression tester
- Edgewise Crush Resistance Test, ECT
- Flat Crush Resistance Test, FCT
- Bending stiffness
- Torque test