How to make carton box VI : The detection of corrugated cardboard
Corrugated paper is the main material for the manufacture of various cartons and packaging, and its quality and strength will directly affect the effect of carton packaging. The requirements for the quality and strength of corrugated paper are subject to the influence and limitations of the production process and operation, and on the other hand, the requirements for the products to be packaged and the intended use.
Sampling is the first step in the accurate measurement of corrugated board. Sampling should maximize the characteristics of this batch of board, but sampling should be as small as possible.
The humidity and temperature of the air have a great influence on the physical properties of paper and paperboard. It is necessary to do proper humidity control before measurement (the north may need humidification treatment, while the south may need to be drained, and the seasons are treated differently. The way is different.)
The following describes the strength index and test method of corrugated paper.
1. Ring compression strength of corrugated board and carton board
It is difficult to determine the compressive strength perpendicular to the thickness of the paper. It is usually practiced to enclose the paper or paperboard in a loop and then apply pressure, which is much more stable. Therefore, the base paper or paperboard is enclosed in a ring shape, and then the compressive strength is measured, which is the ring pressure strength of the base paper or paperboard.
2. The compressive strength of the corrugated core
The main function of the corrugated core is to maintain the cardboard with a certain thickness when the corrugated cardboard is deformed under pressure, so that the cardboard obtains a large moment of inertia. The corrugated paper core is capable of withstanding the effects of stress and strain, and forms a uniform contour corrugation at high speed erection, and can be firmly adhered to the facial tissue.
This effect of the corrugated core can be measured by the flat compressive strength of the corrugated corrugated core. The flat compressive strength of the corrugated core is determined by first pressing the corrugated base paper into a corrugated shape with a corrugating tester under a certain temperature and a certain pressure. Then, a flat pressure test was carried out on a small test machine to measure the load carrying capacity, and it was expressed by KN (kgf).
3. Compressive strength of corrugated board
An inherent characteristic of corrugated cardboard is that it has a large moment of inertia. When corrugated cardboard is subjected to high pressure inertia, maintaining its original thickness is a prerequisite for maintaining its characteristics.
Corrugated board does not have the ability to be crushed when subjected to flat pressure, and is an important strength indicator for detecting corrugated board. This indicator is particularly important for the flexibility of the corrugated board during use and for maintaining the original thickness of the board during the various processing of the carton.
The flat compressive strength of corrugated cardboard is expressed by the amount of force acting perpendicularly on the basis area of the cardboard, in units of kPa. To determine the flat compressive strength of corrugated board, a small pressure tester can be used, which is sampled in a circular shape with a sample diameter of 5.13 cm.
4. Corrugated board edge strength
The corrugated carton is different from the paper bag in that it is applied as a rigid container and maintains a certain shape when in use. One of the main forms of corrugated box damage is flattening and loss of rigidity. The index that reflects the rigidity of the carton is the compressive strength of the carton, and is directly related to the edge compressive strength of the corrugated board.
The edge compressive strength of corrugated board refers to the ability of the board to withstand compressive loads in the corrugated direction. It is expressed in units of length, in units of N/m. This indicator can be used to compare production under similar conditions, but not in the same batch. The quality of the product; it can also be used to compare the compressive strength of corrugated cardboard produced from different materials.
A special small pressure tester can be used to measure the side pressure strength.
5. Breaking strength
Burst resistance has long been recognized as an important quality indicator for corrugated board and its components (core paper, facial tissue and base paper). Simply put, the amount of force the unit can absorb in the paperboard without breaking.
6. Puncture strength
The puncture strength can be used to measure the resistance of corrugated board to damage caused by the impact of sharp objects. It is a comprehensive indicator. Recent studies have shown that the tear strength of the paper in both the longitudinal and transverse directions is related to the corrugated core paper, and the flat compressive strength of the corrugated medium has an important influence on the strength of the corrugated cardboard.
The puncture strength was measured by a puncture strength meter. The analyzer uses a pendulum-mounted pendulum to measure the ability of the cardboard to resist puncture by changing the positional energy before and after the puncture of the cardboard, and converts the change in potential energy into kinetic energy to puncture and tear the cardboard. To indicate the puncture strength of paper or cardboard.
7. Bond strength
Adhesive strength refers to the bonding strength of corrugated paper to facial tissue or backing paper. Apply an outward pulling force perpendicular to the surface to the face paper or corrugated core paper until the two are separated. The maximum load that the interface of the binder or binder fiber before the separation can withstand is the bond strength of the sample, also known as the peel strength, in units of N.
The bond strength can be measured by a small pressure tester. The tensile force applied to the face paper and the corrugated medium is produced by inserting the upper and lower sets of the rods of the corrugated board, so the test is also called the pin bond strength test.
The above seven indicators can basically reflect the advantages and disadvantages of the board made, it is directly linked to the cost, and the best and the cheapest is impossible.