Heat shrinkable packaging machine has a certain market and quantity at home and abroad. Due to the continuous change of packaging materials in various industries, the heat shrinkable packaging machine has added new vitality and promoted its use more widely, such as food, drink, condiment, groceries, electrical supplies, electronic parts, drugs and their size boxes, one box or two items packaging, etc. However, in the process of design, production and trial production, it is found that the following factors affect the effect of packaging products, which is worthy of further study and discussion.
1、 The performance of film cutter and film sealer affects the performance of automatic channel heat shrinkable packaging machine. The working performance of film cutter and film sealer is an important factor affecting the packaging quality. Before packaging, first of all, it is necessary to level the film cutter and film sealing cutter. The upper cutter bed and the lower cutter bed must be adjusted to be parallel to each other; the pressure adjustment of the press cutter spring is basically the same, and the two cutters must be coordinated when they work. Otherwise, there will be plastic film even knife or tear open phenomenon, a batch of waste products. Then there is the problem of film cutting and sealing sequence. At present, the heat shrinkable packaging machine on the market, generally, the film cutter and the film sealing cutter work simultaneously, or seal the film first and then cut the film, all of which are easy to tear the film. The test shows that the working sequence of cutting film first and then sealing film is effective, which greatly improves the yield of packaging shrinkage.
2、 The influence of the performance of the hot air blower and the structure of the air flow system in the design of various forms of heat shrinkable packaging machine, it is necessary to select the blower first. At the same time, we should pay more attention to the reasonable structure of the hot air circulation pipeline system. For example, the performance of the fan is poor, the design of the deflector, the baffle, the splitter, the regulator and the inlet and outlet of the air flow system is unreasonable, and a large number of waste products will be produced during the heat shrinkable packaging, so it is difficult to debug them well. Therefore, the selection of the hot air blower should be appropriate and the structure design of the air flow system should be reasonable. When the fan works, it can stir up and down the heating temperature evenly, so as to achieve good results.
3、 There is a close relationship between the shrinkage temperature control and the walking conveying speed. The production rate is high, the temperature control is high, the walking conveying speed is fast, and the production efficiency is fast; the production rate is low, on the contrary. Therefore, the debugging and control of the two must be coordinated. For example, if the temperature is too high and the walking speed is too low, the products packaged by the shrinking machine will burst or shrink the film into a mass, and even if it is serious, there will be cave. If the temperature is too low, the walking speed is too fast and the contraction is not complete, wrinkles and fullness will appear. In addition, different shrink film has different adaptation temperature. When using ordinary shrink film packaging, the temperature is generally controlled between 150-160 degrees; when using low-temperature film packaging, the temperature is controlled below 150 degrees. The control of shrinkage temperature is related to the thickness of shrinkage film. 2. For the thin shrink film below 0 threads, the temperature should be adjusted down a little according to the actual situation, and the walking speed should be faster; for the shrink film above 2.0 threads, the temperature should be adjusted up a little, and the walking speed can be adjusted down a little. In a word, in order to debug and control according to the actual situation, only by mastering their performance laws and mutual relations, can beautiful products be packaged.
4、 The influence of shrink film exhaust when the goods need to be completely sealed packaging, special attention should be paid to the problem of shrink exhaust. When the packaging machine transmits the packed goods to the heat shrinkable room, the packaging film begins to shrink under the influence of temperature, and exhausts while shrinking. Generally, the exhausts are eliminated through small pinholes on the perforator. At this time, the exhaust speed and shrinkage speed of micropores are basically the same, so the packed products are full and beautiful. However, when the package is too large, the microporous exhaust speed is less than the shrinkage speed, which will generate residual air bubbles, and even cause the burst of the coating, which will affect the packaging quality. Therefore, when packaging large-scale goods, the number of perforators should be added, and enough air holes should be punched in the process of film delivery, so the shrinkage effect will be improved.
