Small precision three-layer co-extrusion blown film experimental line is a key equipment to improve film quality

Publish Time: 2025-04-09

With the continuous emergence of new polymer materials and the increasing market requirements for the performance of polymer extrusion products, single-component products can no longer meet the requirements of product processing performance, appearance and special functions. In this context, multi-component composite products have emerged, and small precision three-layer co-extrusion blown film experimental line is the key equipment to improve film quality.

Process principles and advantages

The polymer film co-extrusion process is a process in which several extruders are used to supply different molten material flows, which are combined and co-extruded in a composite head to obtain a multi-layer composite film. Small precision three-layer co-extrusion blown film experimental line adopts precision extrusion and high-performance blown film molding technology to add three different materials or colors of plastic particles into three independent feeders respectively. After melting and stirring into a fluid state, they flow through a specially designed three-layer co-extrusion die head under the action of high-pressure gas to blow out a continuous film.

This process allows multiple layers of materials with different characteristics to be compounded with each other during the extrusion process. The products have the excellent characteristics of several different materials and complement each other in characteristics, so as to obtain the performance and appearance required by special requirements. For example, by adopting the blown film co-extrusion production process, the function of the film can be quantitatively controlled through the effective adjustment of the thickness, the structural combination of each layer of the film is convenient and flexible, and the range of substrate selection is wider. The use of this technology to produce composite films can reduce costs, improve strength, increase the barrier properties and added value of the film, and improve the market adaptability of the composite film.

Equipment structure and features

The small precision three-layer co-extrusion blown film experimental line consists of three precision single-screw extruders, a three-layer co-extrusion blown film die head and a blown film auxiliary machine. The electrical components and screw barrel of the extruder are all well-known domestic and foreign brand products, with a screw diameter of 25mm, an aspect ratio of 28L/D, a maximum screw speed of 120rpm, and 38CrMoAlA advanced nitrided steel, which has the characteristics of high wear resistance, high fatigue strength, high strength and durability.

The equipment is driven by a servo motor, with stable plasticization, good consistency and low noise. Each roller is controlled by a servo motor to ensure accurate and stable operation of each roller. Branded melt pressure and temperature sensors are selected, with high test data accuracy. The maximum temperature of the barrel temperature control can reach 350℃, and the temperature control accuracy is ±1℃. The three-layer co-extrusion blown film die head adopts a concentric sleeve design, which can independently adjust the width, thickness and layer ratio. The flow channel is smooth without dead corners and material stagnation, and the material is discharged evenly. The film blowing auxiliary machine integrates functions such as traction, trimming, and winding. The servo drive of the film blowing frame can adjust the height up and down, which is convenient for film guiding and process control.

Application field

The small precision three-layer co-extrusion blown film experimental line is widely used in the fields of new material formula research and development, film blowing performance testing, film blowing production process optimization, and preparation of three-layer blown tubular film. In the food, medicine, daily chemical product packaging, agricultural greenhouses, water conservancy projects, environmental engineering and other industries, there is a huge market demand for high-barrier packaging films, shrink films, hollow cling films, geomembranes and other film products, and this equipment is the key tool for the research and development and production of these high-quality films.

For example, in the field of food packaging, this equipment can be used to prepare films with high barrier properties, moisture-proof, and fresh-keeping functions, effectively extending the shelf life of food; in the field of agricultural greenhouses, it can produce films with good light transmittance, heat preservation and anti-aging properties, and improve the yield and quality of crops.

With its advanced process principles, sophisticated equipment structure and wide application fields, the small precision three-layer co-extrusion blown film experimental line has become a key equipment for improving film quality, providing strong support for the development of the polymer materials industry.