A multi-layer co extrusion MDO stretch shrink POF film production equipment - using a 5-layer co extrusion composite method. Can produce new environmentally friendly packaging materials. Has ultra-high transparency. Glossiness. Memory contraction. High barrier properties. Strong puncture resistance. Good heat sealing performance and the above advantages. Can replace expensive imported equipment from Europe and America.
The device structure is as follows:
S0-1 rectangular rack platform. Made by welding and assembling square tube steel. Equipped with guardrails. stairs. Platform.
On the S1 platform, it is 180 degrees. Place 5 extruders. The extruder consists of (drive motor, reducer, base, screw, heater, cooling fan, screen changer)
S2-5 extruders are connected to the mold. The mold has a 5-layer stacked structure. Equipped with a heater. Diverter. Model body.
S3- The lower side of the mold is equipped with a cooling air ring. Cooling water ring. Water ring gauze. Install them sequentially above the lifting platform. According to the actual production process requirements. Free adjustment of height position.
S4- The lifting platform is equipped with a T-shaped screw. Screw. Bracket. Chain wheel. Chain. Drive, motor.
S5- The traction device is placed on the ground. The lifting platform is installed on top of the traction device. The traction device is equipped with two longitudinal stretching pulls. They are the first traction and the second traction, respectively. Each is equipped with rubber sticks. steel rod. Cylinder. Reducer, drive motor. The first traction is equipped with a herringbone board and a water tank. The herringbone plate is made of stainless steel plate
S6- The traction bracket is connected to frame 2. Each is equipped with guide rollers. Spread the flat stick. Tension sensor.
S7-2 rack. It is a multi story tower frame platform structure. Assembled by welding square tube steel. The height is around 15 meters. Equipped with guardrails. stairs. Guide roller bracket.
The topmost part of rack S8-2. Install the third longitudinal stretching traction device. Equipped with traction rollers. Cylinder. Drive motor, reducer.
S9- Place the third traction device on the lower side. The outer side of the two far-infrared ovens is made of stainless steel material. There is asbestos inside. Thermal insulation cotton. Heating wire. Ceramic tiles.
S10- The lower side of the oven is the cooling and shaping area. Divided into 3 cooling stages. There are three cooling air rings. Blower. Bracket.
S11- Place a stable foam rack on the lower side of the cooling area. Plays a stabilizing role in membrane bubble oscillation.
S12- Place the stable foam rack on the lower side. Rotating platform. Winder. The fourth traction.
S13- The rotating platform is installed on the base bracket. Equipped with a rotating gear plate and large gear. pinion. Drive the motor. Reducer. Conductive ring. It can rotate 360 degrees in both directions.
S14- The rewinder is installed on a rotating platform. Winder center coiling dual station structure. It has AB axis 360 degree bidirectional flipping. Automatic roll change. Automatic cutting, online slitting function.
S15- The fourth traction is installed at 1/3 behind the top of the rewinder. Vertically concentric with the center point of the rotating platform. The traction device is equipped with traction rollers. Drive the motor. Reducer. Herringbone frame. Cylinder.
The S16 herringbone board consists of guide rollers and brackets.
S17- The electrical control cabinet is placed on the outside of rack 2. Easy to maintain and operate. The electrical cabinet is equipped with. Frequency converter. Electrical component switch. Control the circuit. PLC module. Industrial control touch screen. Thickness gauge control cabinet.
The thickness gauge scanning frame is installed on the fourth traction A-frame. Follow the rotating frame. Real time online measurement of membrane bubble thickness.
Technological process:
1. Use different grades of PE.PP. Resin raw materials, functional masterbatch, and additives. Put it into the hopper. Through the weighing vector device. Accurately enter the heating material barrel screw according to the set ratio. The screw is driven to rotate by the driving motor. Heat the solid raw material and plasticize it into a solution. Enter the composite mold. Form a circular membrane embryo for ring assembly. Flow vertically downwards.
2. Add air holes at the top end of the mold. Gas filling valve. Inject compressed air. Inflate inside the membrane embryo. Adding air increases the diameter of the mold base. Conversely, it becomes smaller. The diameter of the embryo increases - the width of the membrane widens. Conversely, it narrows. The first inflation width of the membrane embryo. It depends on the amount of air entering. The thickness depends on the extrusion volume of the extruder and the first traction and stretching speed. The extruder speed is fast - the extrusion volume increases and the film embryo becomes thicker. Conversely, it becomes smaller. The traction speed is fast and the mold base becomes thinner. Conversely, it becomes thicker.
3. The embryo enters the wind ring vertically downwards. Water ring. Water ring gauze. Two steps of cooling and shaping (air+water). Flatten the herringbone board into a sheet-like substrate.
4. The sheet substrate enters the first traction. The second traction. Longitudinal stretching. Pass through the guide roller from bottom to top. Enter the third traction device for longitudinal stretching. The stretching ratio determines the longitudinal shrinkage rate of the film. The larger the stretching ratio. The greater the longitudinal contraction rate of memory.
5. The sheet softens after entering the far-infrared oven. Vertically pass through the wind ring. Stable foam rack. Herringbone frame. Enter the fourth traction device. Inject air into the membrane embryo. Perform 3-5 times inflation and lateral stretching. Finally, enter the winding machine. Roll up the cylindrical substrate.
6. Under the oven. Equipped with a cooling air ring. Stable foam rack. Cooling and shaping of horizontally stretched and inflated film bubbles.
7. Thickness gauge - installed on the A-frame. Follow the circular rotation of the rotating frame. Scanning measurement of thin films. Measurement methods are divided. Non contact infrared light measurement. Contact capacitive measurement.
8. The membrane bubble enters the winding area. According to the size requirements of the film specifications. Online cutting. The winding machine can rotate 360 degrees in both directions. Eliminate the accumulation point of membrane bubble thickness deviation. Improve the flatness of the membrane surface.
9. The winding machine has. Automatic roll change. Record rice online. Online slitting function. High degree of automation. Easy to operate.
Editor:Sichuan Jinzhongde Science and Technology Research Institute
