Creep under compression
Varipress
- Specific characterisation for Old Corrugated Cardboard (OCC), liners et fluting
- Equipment dedicated to compressive tests in an atmosphere with variable humidity
- Accelerated creep tests
General informations
A kingpin of the packaging sector, corrugated board must retain all its characteristics when subject to temperature and humidity variations during transport and storage.
Predicting the lifetime of a packaging subject to variable humidity includes evaluating its behaviour during creep tests. The Varipress is a specific device which provides access to additional information regarding the capacity of a paper to resist compression and buckling under restrictive
humidity conditions.
Technical Data and Achievements
Measurement principle
The test pieces take the form of columns of paper placed inside perforated rolls. They are pressurised using a pneumatic jack connected to a displacement sensor. Deformation and then crushing occur in the free space between the two rolls.
The test is accelerated by applying programmable cycles of humidity, until the test piece collapses in on itself.
Technical details
- Adjustable loading up to 1000N
- Programmable humidity of 15% to 90% RH
- Rolls with diameter 19 mm or 38 mm depending on paper rigidity
- Duration of test: from 1 to 10 days
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| Varipress column | Varipress |