Tensile Tests
Tensile tests inform about a number of characteristics: stiffness, modulus, tensile strength, tearing length and energy absorbtion.
In a pin adhesion test, the upper and lower layer of a corrugated board strip are separated from the fluting with two rows of inserted steel pins. Test result is the maximum force, related to the total glue line length between layers and the fluting. The Zwick test rig is stiff (see picture), works in tensile mode and requires no compression plates.
This test is according to TAPPI T 821.
Runability at the Wet End
The paper is very susceptible to web breaks when it leaves the paper former machine and runs without any support by a felt or a screen. Adjusting and controlling the web tension, as well as using wet paper with minimal initial tensile strength values, can avoid web breaks. The minimal tensile strength of the paper depends on the stock composition (ratio of long and short fibers, chemical additives). The optimal price-strength-ratio can be evaluat-ed through initial wet tensile tests. Special tensile grips assure correct clamping, draining within the clamping area of the specimen, and prevents specimen breaks within the clamping area.
The advantages:
- Correct specimen gripping
- Fast and easy handling
- High flexibility through the testXpert® II Master Test Program
Since only the tear strength or tearing length result is to be determined in many cases, other results can be hidden by software. The testXpert® II software from Zwick accomplishes this with two functional levels. The first level is the use of built-in Standard tests.
Standard tests (to EN ISO 1924 or TAPPI T 494) contain only test sequences and results which are required by test standards. The advantage of using the Standard tests is that training can be accomplished in a short time. The second level is the Master program. This level will provide functionality to meet all current and future needs for maximum flexibility.
The advantage:
- New: With videoXtens for Poisson´s ratio determination
