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, welded and assembled from square tube steel, equipped with guardrails, stairs, and platform.
On the S1 platform at a 180 degree angle, 5 extruders are placed, consisting of a drive motor, reducer, base, screw, heater, cooling fan, and screen changer.
S2-5 extruders are connected to molds, which have a 5-layer stacked structure and are equipped with heaters, splitters, and molds.
S3- The lower side of the mold is equipped with a cooling air ring, a cooling water ring, and a water ring gauze. Installed sequentially above the lifting platform, the height and position can be freely adjusted according to actual production process requirements.
The S4 lifting platform is equipped with T-shaped screws, screws, brackets, sprockets, chains, drives, and motors.
S5- The traction device is placed on the ground, and the lifting platform is installed on top of the traction device. The traction device is equipped with two longitudinal tensile pulls, namely the first pull and the second pull. They are equipped with rubber sticks, steel sticks, cylinders, reducers, and drive motors. The first traction is equipped with a herringbone plate and a water tank, and the herringbone plate is made of stainless steel.
S6- The traction bracket is connected to frame 2 and is equipped with guide rollers, flattening bars, and tension sensors.
S7-2 rack is a multi-layer tower frame platform structure, assembled by welding square tube steel. The height is about 15 meters, equipped with guardrails, stairs, and guide roller brackets.
At the top of the top of frame S8-2, a third longitudinal stretching traction device is installed, equipped with traction rollers, cylinders, drive motors, and reducers.
S9- The lower side of the third traction device is placed, and the outer side of the second track (far-infrared oven) is made of stainless steel material, with asbestos, insulation cotton, heating wire, and ceramic tiles inside.
The lower side of the S10 oven is the cooling and shaping part, which is cooled in three stages and equipped with three cooling air rings, blowers, and brackets.
S11- Place a stable foam rack on the lower side of the cooling area to stabilize the oscillation of the membrane foam.
S12- Bottom placement of stable foam rack, rotating platform, winding machine, 4th traction.
The S13 rotating platform is installed on the base bracket and is equipped with a rotating gear plate, a large gear, a small gear, a driving motor, a reducer, and a conductive ring, which can rotate 360 degrees in both directions.
S14- The winding machine is installed on a rotating platform, with a winding machine center winding dual station structure, featuring AB axis 360 degree bidirectional flipping, automatic roll changing, automatic cutting, and online slitting functions.
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.
