Logo
    Contact us
    Address of general department: No.2, end of Chaoyang Road, Jinyuan Industrial Zone, Shantou City, Guangdong Province (junction with Jinfeng Road) Tel:86-0754-82312127 (switchboard) 86-0754-88212599, 888881005 (Sales Department) Tel:13829480446 (General Manager) 18666685446 (foreign trade department) 18666685280 (domestic sales department) Yuenan Maoxin limited company address: Vietnam, Hanoi, Hedong, Suyou Road, the pride, building cT4, room 2612 Tel: 0084462810457 (switchboard) 0084 975697998 (overseas business department)
    Product knowledge Location:Home >> News >> Product knowledge >> Detailed content

    [share] 17 common problems of blown film (with solutions)

    release time:2020-03-04  viewed:674次
     Blow molding is a common processing method in the process of plastic processing, such as vest bag and agricultural film, which are all products of blow molding film. The blow molding process seems simple, but there is a mystery. Xiao Bian has sorted out 17 problems in film blowing and shared them with you.
     
     
     
    1. Die drawing difficulty
     
     
    (1) Improper head temperature control: properly adjust the head temperature.
     
     
    (2) Uneven die discharge: the die gap should be adjusted and the head connector temperature should be adjusted properly. This article comes from Zhimeng
     
     
    (3) There are coke impurities in the melt: clean the raw materials and clean the head and screw.
     
     
    (4) Improper control of extrusion process conditions: the process conditions should be properly adjusted. 
     
     
     
    2. Deviation of vesicle tube
     
     
     
    (1) Too high temperature of body and die: reduce properly.
     
     
    (2) Head connector temperature too high: reduce properly. Dedecms.com
     
     
    (3) Uneven die discharge, uneven film thickness: adjust die gap and head connector temperature properly.
     
     
     
    3. The vesicle tube is in the shape of reed
     
     
     
    (1) The clamping force of the traction roller is too small, or the rotation speed of the traction roller is affected by the regular change of the mechanical transmission resistance: increase the clamping force of the traction roller appropriately, repair the mechanical transmission part of the traction device, and make the rotation speed of the traction roller stable. Zhimeng content management system
     
     
     
    (2) The traction speed is not stable, and the wind pressure of the cooling air ring is too large: for this, the traction speed should be adjusted to make its operation stable; the wind pressure of the air ring should be appropriately reduced.
     
     
    4. Vesicular oscillation
     
     
    (1) Melt temperature is too high: properly reduce the temperature of the fuselage and head. Dedecms.com
     
     
    (2) Cooling efficiency of cooling air ring is too low: increase air pressure and air volume of air ring appropriately.
     
     
    (3) The friction between the bubble tube and the herringbone splint is too large: increase the angle of the herringbone splint appropriately, and reduce the contact area between the bubble tube and the splint. Good dream weaving, good dream weaving
     
     
    (4) Head temperature is too low, discharging is difficult, bubble beat: properly increase head temperature and screw speed. Good dream weaving, good dream weaving
     
     
    This article comes from Zhimeng
     
     
     
    5. Blooming on the surface of film
     
     
    (1) The temperature of the fuselage or head is low, and the melting material is not well plasticized: properly increase the temperature of the fuselage or head.
     
    (2) Screw speed is too fast: slow down properly.
     
     
    (3) Screw temperature is too high or too low: adjust the flow of cooling medium in the screw to control the screw temperature within the appropriate temperature range.
     
     
     
    6. Obvious hanging line
     
     
    (1) There is decomposition material or impurity adhesion at the outlet of the die: scrape away the impurity or coke with a copper shovel, and lift out the mandrel for cleaning in serious cases.
     
     
    (2) Bruised die: trimming die.
     
     
    (3) Head internal pressure is too small: add filter screen. Content from dedecms
     
    (4) Melt temperature is too high: properly reduce the temperature of the fuselage and head.
     
     
    This article comes from Zhimeng
     
     
    7. Obvious seam line trace
     
     
    (1) Head or head connector temperature too high: reduce properly. But the temperature should not be too low, otherwise, the suture will still be produced.
     
    (2) There is coke sticking on the tip of mandrel: the shape of the tip of mandrel should be modified to make it smooth.
     
     
    (3) Unreasonable head mechanism design: the head design should be modified.
     
     
     
    8. Poor transparency
     
     
    (1) Body or nose temperature too low: increase appropriately. Zhimeng content management system
     
    (2) Insufficient foam tube cooling: improve the cooling efficiency of the cooling system, increase the air pressure and air volume of the air ring, and also appropriately reduce the extrusion speed.
     
     
     
     
    9. There are colloidal particles or white spots in the film
     
     
    (1) Impurities in raw materials: screen out impurities and purify raw materials.
     
    (2) Broken filter screen: replace the filter screen.
     
    (3) Melt over heat decomposition: clean the head and screw, and properly reduce the molding temperature.
     
     
     
     
    10. There are lumps in the film
     
     
    (1) Filter screen is broken: replace the filter screen. This article comes from Zhimeng
     
    (2) Improper control of molding temperature: generally, if the molding temperature is low and the melting material is not plasticized properly, it is easy to produce cold block, so the temperature should be adjusted properly.
     
     
    11. Bubbles
     
     
    (1) Raw materials are not fully dried and moisture content is too high: carry out pre drying treatment.
     
     
    (2) Leakage of cooling water at barrel or hopper: repair cooling pipes and devices, and eliminate leakage. This article comes from Zhimeng
     
     
    12. Uneven thickness of film
     
     
    (1) Improper adjustment of die gap and uneven discharge: adjust die gap.
     
     
    (2) Uneven air output of cooling air ring: adjust and clean the air ring to make its air output uniform.
     
     
    (3) Mandrel deflection deformation: replace the mandrel.
     
     
    (4) Uneven temperature around the head: repair the heating device of the head.
     
    (5) Too large inflation ratio: properly reduce.
     
     
     
    (6) The pressure of compressed air is not stable: repair the air compressor.
     
     
    (7) Unreasonable head structure design: modify the process parameters of the head.
     
    (8) Too little discharge: properly increase the rotation speed of extruder and increase the discharge.
     
     
     
    13. Membrane fold
     
    (1) Uneven film thickness: adjust the film thickness.
     
     
    (2) Insufficient or uneven cooling: enhance cooling efficiency or reduce molding speed properly.
     
     
    (3) The herringbone splint or traction roller is not aligned with the head center: recalibrate the center line.
     
     
    (4) The included angle of herringbone splint is too large: reduce the included angle properly. Sometimes, the included angle of the herringbone splint does not match the diameter of the bubble tube, so it should be adjusted, and the geometry of the splint should be symmetrical. Content from dedecms
     
     
    (5) The clamping force of traction roller is uneven and the tension is different: appropriate

    (6) Reeling tension is not constant: adjust the friction of reeling friction disc to ensure constant reeling tension.
     
     
     
    (7) Uneven head installation: correct the levelness of the head. This article comes from Zhimeng
     
    (8) The air flow outside the bubble tube is unstable: block the screen around the bubble tube to keep the air flow around the bubble tube stable.
     
     
    14. Uneven winding
     
     
    (1) Uneven film thickness: adjust the film thickness. copyright dedecms
     
     
    (2) Traction officer clamping force is uneven, film deviation: adjust the clamping force, so that the clamping force on the roller surface is uniform.
     
     
     
    (3) The air in the bubble tube is entrained into the diaphragm, causing wrinkles: adjust the clamping force of the clamping, and eliminate the gas in the membrane tube.
     
     
     
    15. Poor film opening
     
     
    (1) Temperature of fuselage and nose is too high: reduce appropriately.
     
     
    (2) Traction roller clamping force is too large or traction speed is too fast, poor cooling: reduce clamping force or traction speed.
     
     
    (3) Poor cooling: improve the cooling efficiency of the cooling system.
     
     
    (4) Too little lubricant: add proper amount of internal lubricant.
     
     
     
    (5) Too much plasticizer: reduce the amount of plasticizer and try to select high-efficiency plasticizer.
     
     
    16. Frost line too high
     
     
     
    (1) Head temperature too high: reduce properly. 
     
     
    (2) Too much extrusion: reduce screw speed properly.
     
     
    (3) Insufficient cooling: increase the air volume of cooling air ring.
     
     
     
    17. Frost line too low
     
     
    This article comes from Zhimeng
     
     
    (1) Head temperature too low: increase properly.
     
     
    (2) Too little extrusion: increase screw speed properly.
     
    (3) Excessive cooling: reduce the air volume of cooling air ring.

    A previous: [notice] four major problems of extruder will be solved for you!
    Next news: How to distinguish PE, PO, PP, OPP plastic bag material
    hotline line
    About us
    List certificates
    List Company profile
    List Company culture
    Products
    List Machine profile
    List Electrical product
    News
    List Product knowledge
    List Industry dynamics
    List Company news
    Contact us
    List Contact us
    List Online Message
    Copyright © 2012-2016. Guangdong maoxin electromechanical co., LTD. All rights reserved
    ENGLISH 中文
    收缩
    • QQ咨询

    • Shanghai HongChuang Foreign Trade Co., Ltd
    • 电话咨询

    • 18666685446