Corrugated board manufacturing (4)

The coating machine is a device that combines single-sided corrugated cardboard or multiple single-faced corrugated cardboard plus paper sheets into a three-or-more-layer corrugated paperboard by coating and sticking a full agent. According to the processing structure of corrugated paperboard, the gluing machine is divided into single-layer (for three-layer corrugated board), double-layer (for five-layer corrugated board), and three-layer (for seven-layer corrugated board) gluing mechanism. The gluing device is mainly composed of a preheating roller, a rubber coating roller, a floating roller, a pressure roller, a paper guide roller, a heat insulation plate, an aerodynamic component, an adhesive storage tank, and the like (see Fig. 15).

In order to keep the gluing machine in sync during operation, its drive is driven by the double-sided machine. When the gluing machine is idling, an independent motor runs through the reducer.

The function of the gluing machine is to uniformly apply glue on the peaks of single-sided corrugated cardboard. The specially designed mesh pyramidal pit on the coating roller can save the amount of glue and balance the glue in the work. In order to ensure good bonding quality, the working pressure of the floating pressure roller controlled by the pneumatic element should be no less than 0.5MPa. . The glue roller and the scraper roller are required to maintain a good parallelism, and the working gap between the two is 0.25--0.4 mm.

When three, five, seven or more layers of corrugated cardboard are combined, they enter the drying, setting and cooling system. This system is a double-sided machine section. The double-sided machine consists of a hot section and a cold section. The main role is to fully evaporate the water in the corrugated board, so that the adhesive curing, corrugated stereotypes. The heating section is composed of several sets of hot ovens side by side, and the watch is smooth and clean. The corrugated board is directly attached to the corrugated board. On the upper end surface of the corrugated board, a special canvas belt and a transmission press roll with good air permeability, certain tension and gravity are used to heat and dry the corrugated board under a certain pressure during operation. The heating section is further divided into a high-temperature section and a low-temperature section. The high-temperature section gelatinizes and dries the adhesive to enhance the adhesion. The low temperature zone makes the corrugated board dry and tends to be stable. The function of the cooling section is to disperse excess heat, even moisture, to avoid warping, so that corrugated cardboard smoothly into the next process.

In order to ensure the normal operation of the double-sided machine, the tension of the canvas belt in the operation is appropriate, and the bias is not skewed. It is necessary to timely adjust the pneumatic or manual tension mechanism or control device. Usually keep the canvas clean and dry in order to facilitate good ventilation. The use of the pressure roller should be adjusted according to the molding conditions of the corrugated board and the speed of the automatic production line and the quality of use of various webs in order to ensure the quality of the corrugated board.

The slitting section mainly consists of a slitting machine for a slitting and creasing machine. The function of the slitting and indentation part is to cut the corrugated cardboard into the indentation which has a certain width and a longitudinal bending requirement of the corrugated cardboard at the time of slitting according to production requirements. Slitters are generally two-component slitting and creasing machines. According to the production needs, the two sets of required sizes can be adjusted at the same time. When changing the production specifications, just start the electrical control device and turn the device 180°, you can put it into use, reduce downtime, reduce consumption, and increase production efficiency. . In order to ensure that the slitting knife does not make the cutting edge of the corrugated cardboard in the cutting process and the surface paper cracking meets the national standard, the fitting gap after the adjustment of each group of the garden knife should be less than 0.04 mm.

The slitting and creasing machine itself has an adjusting mechanism for slitting the upper and lower gaps of the garden knife and the indentation wheel. According to the different thicknesses of the corrugated cardboard, it is necessary to timely adjust. Guaranteed slitting and indentation quality.

The indentation wheel of the slitting and creasing machine has been studied and discussed by many packaging technicians. Now it is more popular to use the point-type indentation wheel developed by Comrade Song Shibin of Xi'an Qinchuan Mechanical Carton Factory (Figure 16).

The characteristics of the five-point indentation wheel are: the centerline is prominent, the indentation dimension is accurate and the groove width is 6.4mm, so that the corrugated board has sufficient deformation; the shoulders are beveled, so that the corrugated board is rolled The corrugated is well damaged and the stress is not concentrated; the corrugated board is naturally deformed and marks are formed without breaking.

The cross cutting machine mainly completes the horizontal cutting of the corrugated board according to certain specifications. It is composed of upper and lower two rollers with long blades that can be rotated to form a set of devices that perform instantaneous shearing when flipped to a certain angle. The rotation of the double roller equipped with a long knife is equipped with adjustable gearless anastomosis transmission to ensure the precision of cutting. When the gear wears, the gear clearance can be readjusted. The use of a cross-cutting machine is to ensure the use and adjustment of the continuously variable transmission because the change of the speed ratio is related to the length of the cut coal of the corrugated cardboard. In the running process, the tension of the corrugated board must be controlled according to the quality of the corrugated board so as to prevent the thickness of the corrugated board from being affected due to the self-weight of the driving roll itself plus a certain tension.

The key to the use of a cross cutting machine is the installation and adjustment of the blades. The installation of the two long knives of the cross cutting machine is done with a press plate and bolts on the large shaft. The adjustment of the blade is mainly to adjust the fitting gap of the two blades when the cutter shaft rotates. The best fit clearance should be 0.05mm. In this way, the cutter shaft will not produce blade bite and impact during rotation, at the same time it will rotate lightly, and the edge of the cut corrugated cardboard will be smooth and tidy, and the knife edge will meet the requirements of national standards.