"Cold" Corrugated--Application of Ultrasonic Technology to Tile Line (6)

Board strength tests include side pressure strength test (ECT) and flat pressure strength test (FCT). These two tests are often used to check the quality of the board, and are not affected by the quality of the board's bonding. The FCT showed that as the production speed increased, the flat compressive strength of the paperboard was reduced from 140N to 40N, but this may be due to the non-compliance of the non-heated corrugating roller (see Figures 13 and 14).

(Figure 14 FCT value and CMT value (consistent) compared to traditional production of single-sided corrugated cardboard)

The side pressure strength has little to do with the production speed (see Figure 15 and Figure 16). The edge pressure strength of the paperboard is closely related to the SCT of the paper.

(Fig. 16 Comparison of ECT value with single-sided corrugated cardboard produced by the traditional method)

(five) Summary

The test results show that:

The paper used must contain some paste. The bond strength largely depends on the paper grade.
It is necessary to humidify the corrugated tip because the humidity of the paper itself is not sufficient to achieve a satisfactory result.
The actual production experiment shows that at the production speed, the bond strength will decrease.
Cardboard ECT and FCT values ​​are lower than those of conventionally produced cardboard.
In the continuous operation of the hot roller may cause the temperature is too high and affect the normal production, so need to cool the temperature-sensitive unit.
When the corrugated tip passes through, the vibrations transmitted by the ultrasonic transmission unit delivery outlet package may damage the ultrasonic contact, the processor, and the supercharger. This will have a major impact on the quality of the bond.

Ultrasonic contacts are expensive and contact with rough paper surfaces under pressure and are prone to wear. This will increase production costs.

Experiments have shown that ultrasonic technology can be used to produce three-layer corrugated cardboard. But still need the traditional paste and hot plate technology.

The possibility of producing corrugated paperboard using the principle of ultrasonic technology has been verified and developed from different perspectives. Practice has proved that this technology can be applied to actual production, but subject to: cardboard type, grade and production speed limitations b Dan Dan maintenance, replacement of titanium ultrasonic contacts, and continuous hot wet mouth of the core paper will be Lead to increased production costs. All of the above drawbacks have caused ultrasound technology to be unsuitable for the production of three-layer corrugated cardboard. Even in the static test, the adhesion results are not uniform and the heating step cannot be saved in order to ensure good molding and control of board warpage. Ultrasonic bonding technology is suitable for the production of certain small batches of special products, especially for the production of narrow corrugated cardboard. However, during the production process, be aware of fire hazards.

(Translated / Li Xiaolei)

Corrugated Carton, July 2005 issue