Views:164 Author:Site Editor Publish Time: 2017-10-07 Origin:Site
Bursting strength is the maximum pressure that the paper or paperboard can withstand the uniform increase of the surface of the specimen on the unit area under experimental conditions.
Bursting strength commonly used units: kpa, lbf/in2, kgf/cm2.
The conversions between the three are:
The unit of bursting strength is a pressure unit, not a quality unit. So we usually talk about such as "breaking strength of 20 kg, breaking strength of 14 pounds", and so on, from the strict sense is not accurate, should be called the strength of 20 kilograms per square centimeter, 14 pounds per square inch force.
Broken with the weight of the machine has nothing to do with the impact of the durability of paperboard has the following factors:
1, corrugated box Bursting strength by the composition of the cardboard inside, the outer layer and the original paper itself to burst the strength of the decision, and corrugated core paper has nothing to do.
2. The strength of the original paper itself is mainly determined by the original paper fiber. The breaking resistance is related to the fiber length and the adhesion between the fibers, the fiber length increases, and the resultant strength of the fiber increases, which increases the resistance to breaking. The paper made by the original wood pulp is more resistant to breaking than the recycled pulp, and the coniferous wood pulp is high in the paper. In addition, It is also helpful to improve the breaking strength of the original paper by adding some additives in the process of copy-making.
3, paperboard moisture content in the $number, the maximum resistance to breaking value. When the moisture content changes in the 8~14% range, the breaking value changes no more than 5%, but the moisture content reaches 18% when the breaking down value can reach about 10%. That is to say, the corrugated box in the relative humidity for the 50%RH~80%RH environment storage, Its breaking strength change amplitude is very small, therefore can dispense the specimen temperature and humidity balance processing process, thus greatly shortens the test time.
4, the original paper or carton storage environment to 25±5℃, 55±5%RH environment is appropriate.
5, Reel paper in the warehouse for a long time stacking will cause the original paper fiber fatigue, resulting in a broken down. The experiment shows that the original paper stacking time exceeds 3 months, its breaking value will decrease 5~8%, the pile time is more than 6 months, and the damage-resistant strength loss will reach more than 10%.