Packaging film blowing technology and Application

Packaging film blowing technology and application

improvement of film blowing process

film blowing process mainly refers to some main steps in film blowing production, such as extrusion, molding, cooling, traction and winding. Their main purpose is to ensure the quality and output of products. When it comes to output, it is an important factor to reduce production cost. There are many factors affecting output, but increasing extrusion It is easy to improve the traction speed. The main factor is the design and processing level of the head. The multi-layer plane stacking die mentioned in this paper will naturally increase the output due to the doubling of the number of extrusion layers, the large heat absorption area and good plasticizing effect. Supplemented by the improvement of cooling technology, the output can be increased by 50%

the so-called cooling technology reminds people of air ring, internal cooling and chiller, which are widely used technologies. People often think that these technologies can improve output, but few people use them to improve quality. In North America, cooling technology is mainly used to improve quality. They use ethylene glycol chiller to replace chiller and propose that the outlet temperature of air ring and internal cooling should reach 5C, The purpose is to improve the cooling and crystallization speed, which will improve the transparency, strength and toughness of products, that is, to improve economic benefits. Among the cooling methods, the effect of water cooling is the best. However, from the perspective of hygiene, water cooling is not allowed for medical film and food packaging film. Even the cold water roller with gate structure corresponding to single arm structure in casting can not be used, because the temperature difference between indoor air and cold water will condense water vapor on the surface of the cooling roller, which does not meet the hygienic requirements, The production workshop of products must also meet these hygiene requirements

because the plane stacking head feeds from the side, the head cannot rotate, so it has to adopt the upper traction rotation. The upper traction rotation is also divided into several types in the world. Although the shape is different, the work is very reliable. Due to the influence of the rotation principle itself, the film will produce periodic offset. If the edge is not cut during winding, an electronic deviation correction device should be added

by improving a series of technical levels such as extrusion, molding, cooling, traction and winding of film blowing machine, we have produced high-quality multi-layer coextrusion films, which are applied in all walks of life, such as infusion bags for hospitals and packaging bags for all kinds of food. In short, it is an obvious trend to produce packaging films with high strength, high barrier and high transparency. On this premise, improve the quality, Cost reduction is the main task. With the continuous improvement of market requirements and film blowing technology, the number of CO extruded layers will be more. However, in China, the specification of packaging film blowing equipment will tend to be miniaturized

from the influence of film blowing process on product quality, small-size multi-layer coextrusion film blowing equipment has many advantages. First, the film quality is good; The film here refers to high-grade films such as infusion film and high resistance diaphragm. The bubble diameter of the products produced by small-scale coextrusion equipment is moderate, and the cooling effect of the cold air from the refrigeration unit is the best in this specification. Moreover, the surface quality of the finished products is the best whether it is traction, rotation or winding, and it is not easy to wrinkle. Second, the performance price ratio is high; Small size equipment is not small at all. This kind of five layer plane superposition machine head may solve the problem. The output of small size film can be produced through the transformation of die. While improving the quality, its output is 1.5 times that of other similar equipment. It has the advantages of low price, low energy consumption, high production efficiency, small rack height, low plant height, good control of sanitary environment, and can be accepted by more users. Through cost analysis, it can be calculated that if the output of products produced by two small equipment is the same as that of one large equipment, the total cost of such two small equipment is less than that of one large equipment, and the quality of products produced by small equipment is higher than that of large equipment. Third, wide adaptability; All large equipment producing packaging film must go through the process of slitting before the finished product is completed. More slitting will affect the winding effect. At the same time, this equipment cannot produce small-size cylindrical packaging film, such as heavy packaging bags. The small machine can blow cylindrical and slitting packaging films of any specification and number of layers within the range of 0 – 800mm. Without modifying any equipment configuration, it can produce the most types of products and meet the diversified requirements of the market. Most importantly, under such specifications and costs, the products have great quality and price advantages and are in an invincible position in the market competition

source: (Jia Zhige, foreign expert of Dalian Bingshan rubber and Plastic Co., Ltd. to improve the filtration efficiency)