stretch film production technology and equipment

stretch film production technology and equipment

stretch film production technology and equipment

stretch film using extrusion processing technology, its main raw material for polyvinyl chloride (PVC), low density polyethylene (PE-LD), ethylene - vinyl acetate acid copolymer (EVA), linear low density polyethylene (PE-LLD) polybutadiene (PB) with a viscoelastic polymer such as,, present, mainly PE-LLD, PE-LD, in order to composite film-based. The main equipment for the extruder and the corresponding auxiliary equipment, such as batching, mixing, feeding systems, thickness measurement system and take-up system. There are two main production processes, namely, casting process and the blow molding process, advantages and disadvantages, the production of stretch film and performance of the necessary equipment such as shown in Table 1.

   Blow molding processes generally use single or multi-layer co-extruded blown stretch film equipment; casting process is used casting production lines. Multi-layer co-extrusion blow molding equipment is imported (usually three), can produce the maximum film width up to 2m, made single or double blow molding equipment to produce the maximum width of LLDPE stretch film 0.5m or 1m. Italy DOLIC (Nextrom company) made a single cast production line annual production capacity of up to 7ktfilm, line speed up to 550m/min, three-layer co-extruded stretch film is special equipment for more advanced equipment is currently one of the world. In addition, Austria SML company in January 2005 for the German Orbita stretch film company took delivery of a pe stretch film production line. The equipment consists of three sets of extruder, 2500mm wide can be produced per hour, five-story stretch film 2500kg. According to the width of the different production lines, the maximum amount out of 4500kg / h. The production line adopts die packet system, reducing the stretch film of the neck, LLDPE stretch film to ensure stable production at high speed, is the world's most advanced and largest output of cast stretch films production line.

   China's current foreign-funded enterprises and joint ventures, mostly imported equipment, large production capacity, such as China, Taiwan-funded enterprises through joint Italian Plastic Co., Ltd has three production lines, each line of investment of 200 million dollars; Beijing Packing Co., Ltd. has introduced a the same production line. Imported production line speed, high degree of automation, high yield, good quality, but large amount of investment. An imported production lines need to invest thousands of yuan, the production capacity of 5-7kt / a; and domestic equipment a pallet stretch film production line invested 20 million, one-way stretch films production capacity is generally 200-300t / a, the annual production capacity is generally 100 -150t.

   As the domestic LLDPE stretch film production line of small, fast adjustment of the product, can be more variety, small batch production, is the largest in the country, the competitiveness of a strong, but the appearance of the product of poor quality, thickness uniformity is poor, the operating rate is not high, average of 50% -60%. Now I stretch film in China has reached a high level of quality.

   China's current stretch film manufacturer in three-or single-layer co-extrusion process to produce the main cast, stretch films thickness 20-50μm. The North American pallet stretch film for more than the standard five, nine facilities have been put into industrial production; and is developing ten layer and 14th stories of production equipment and technology to produce ultra-thin film 0.1μm. Than the single-layer multi-layer due to large output intensity can be reduced in the same film thickness, both to save resources and reduce costs. Film thickness 12-25μm, 20μm of stretch film for the most three-or single-layer co-extruded cast stretch film, so domestic production technology there is still much room for improvement. But China's pallet stretch film quality is very good