How to view the technical parameters of three-layer co extrusion blown film machine

The three-layer co extrusion blown film machine is an important equipment in plastic film production, and its technical parameters directly affect product quality and production efficiency. Correctly understanding and interpreting these parameters is crucial for equipment selection, process optimization, and troubleshooting.

1、 Basic structural parameters

Extruder configuration:

It usually consists of three independent extruders, corresponding to the outer, middle, and inner layers respectively

The screw diameter of each extruder (such as Φ 65mm, Φ 90mm, etc.) determines the plasticizing capacity

The length to diameter ratio (L/D) of the screw is generally between 28:1 and 32:1, which affects the plasticizing effect

Mold head system:

The diameter of the mold head is the core parameter, commonly available in specifications such as Φ 100mm, Φ 150mm, and Φ 200mm

The gap between the mold heads is usually adjustable within the range of 0.8-2.5mm

There are different types of die structures such as spiral and heart-shaped

Cooling system:

The diameter of the wind ring needs to match the mold head

The cooling air volume (m ³/h) and air pressure (Pa) affect the film cooling effect

Dual air vents or dual cold air rings design can improve cooling efficiency

2、 Production capacity parameters

Production range:

Usually expressed in kg/h, such as 50-150kg/h

Related to factors such as raw material type, film thickness, width, etc

The total output of the three-layer structure is the sum of the extrusion amounts of each layer

Film specifications:

Can produce film widths (bending diameters) such as 300-2000mm

The thickness range is usually 0.01-0.15mm

Inflation ratio (2.5:1 to 4:1) affects film properties

Production speed

The line speed is generally 15-80m/min

The traction speed should match the extrusion speed

There is a difference between the maximum mechanical speed and the actual production speed

3、 Electrical control parameters

Drive system:

Extruder motor power (kW) such as 15kW, 22kW, 37kW, etc

The brand and model of the frequency converter affect the control accuracy

Traction motor power and reduction ratio

Heating system:

Number of heating sections (usually 4-6 zones)

Heating power per zone (kW)

Maximum operating temperature (usually around 300 ℃)

Control system:

PLC brand and model

Dimensions and functions of human-machine interface

Temperature control accuracy (± 1 ℃ or higher)

4、 Material adaptability parameters

Applicable raw materials:

Can process LDPE, LLDPE, HDPE, PP, EVA, etc

Matching requirements for melt index (MI) of each layer of raw materials

Limitation on the proportion of color masterbatch added

Interlayer bonding force:

Selection of bonding layer material

Index of interlayer peel strength

Compatibility requirements for blending

Recycled material ratio:

Allow the addition of recycled materials to a large proportion

Configuration of Recycling Material Processing System

The impact on the performance of the final product

5、 Energy consumption and efficiency parameters

Unit energy consumption:

Power consumption per kilogram of product (kWh/kg)

Proportion of energy consumption in heating system

Energy consumption of cooling system

Equipment efficiency:

Preparation time for startup

Change mold and color time

Scrap rate index

Automation level:

Accuracy of automatic thickness measurement system

Automatic winding system configuration

Online detection function

6、 Quality index parameters

Physical properties:

Thickness uniformity (± 5% or higher)

Tensile strength (MD/TD)

Elongation at break

Optical performance:

haze

gloss

transparency

Heat sealing performance:

heat seal strength

Heat sealing temperature range

Hot viscosity

7、 Selection precautions

Matching principle:

Matching production demand with equipment capacity

Matching product specifications with equipment parameters

Matching of raw material characteristics and equipment adaptability

Scalability considerations:

Future product upgrade space

Equipment modification possibility

New technology compatibility

Cost effectiveness evaluation:

Initial investment cost

Operation and maintenance costs

Energy consumption and labor costs

8、 Parameter optimization direction

Process parameter optimization:

Temperature curve setting

Screw speed matching

Traction ratio control

Device upgrade path:

IBC internal cooling system addition

Automatic control system upgrade

Efficient and energy-saving renovation

New product development:

Multi-layer composite film

Functional film

Ultra thin/thick film

Understanding the technical parameters of a three-layer co extrusion blown film machine requires consideration of specific production needs, and the importance of each parameter may vary in different application scenarios. It is recommended that users not only pay attention to the paper parameters when purchasing equipment, but also examine actual production cases and equipment operation stability in order to make better choices.