success in the blow film making machine, blown film machine, blown film extrusion, plastic inflation machine, blown film extruder, blown film machinery

success in the blow film making machine, blown film machine, blown film extrusion, plastic inflation machine, blown film extruder, blown film machinery

know about blown film machine aba multi layer film line co-extrusion film plant 3-layer Co-extrusion Blown Film Extrusion Line Find out the properties of blown films and how the thickness of blown films results in enhancing in its resistance properties also. Learn about the different types of blown films and its package benefiting properties. Blown film is also applied as film line in packaging as lining gives additional strength to the outer material and keeps the product safe from external atmospheric influence. Mono layer blown film line acts as a lamination for jute bags, aluminum foils, woven sacks, etc. Multilayer blown films are many times thicker and tougher than mono layer blown films. It is widely applied for its puncture resistance and dart impact strength properties. Some of the industries that benefit from multi-layer blown films lines are beverages, edible oil, instant tea, and many liquid products. PPTQ blown film machine is applied to obtain high quality of tough blown films that can be used to obtain complete moisture resistance and sealing properties. Food industry finds a great percentage of application of PPTQ blown film line. Blown film and blown film line manufacturers like http://www.oceanextrusions.com/mono-layerblownfilmplant-.html offer high quality machinery to produce wide range of blown films that are then used for packaging industry. These machines can produce different types of blown films without any compromise made in its resistance properties. h. https://www.youtube.com/watch?v=UWcqjQWoEgY PE Blown film machine Plastic processing machinery Multilayer coextrusion blown film machine All Product                             has lead to . All polyethylene film applications in packaging, agriculture, lamination, and construction, consumer, industrial, and health care are reviewed and discussed in dept· Multi layer coextrusion … blown film coextrusion lines, multilayer films of HDPE, MDPE, LDPE, LLDPE, EVA, and PP · ABA 3 layer co extrude Single Screw Extrusion Extrusion Process Extrusion Safety Equipment Plastic Behavior Screw Design Processing Conditions Scale-up Shear Rates, Pressure Drops, and Other Extruder Calculations Glossary Twin Screw Extrusion Extrusion Process Extrusion Safety Equipment: Corotating, Counter-rotating, Non-intermeshing, and Conical Plastic Behavior Screw Design Shear Rates, and Other Twin Screw Calculations Polymeric Materials Definition and Identification of Different Polymer Types Polymerization Mechanism Polymer Types and Structure Effect of Molecular Weight on Extrusion Crystalline versus Amorphous Polymers Rheology Physical Properties Polymer Processing PART 2Troubleshooting the Extrusion Process Problem Solving Five Step Process Design of Experiments Quality Troubleshooting: Mechanical, Product, Sheet, Coextrusion, Pipe/Profile, Blown Film, Cast Film Auxiliary Equipment Feed Systems/Blenders Gravimetric/VolumetricFeeders Resin Dryers Gear Pumps Screen Changers Granulators/Pulverizers Screw Cleaning Purge Materials Coextrusion Objective of Coextrusion Equipment Material Consideration Extrusion Applications Compounding Sheet/Film Blown Film Profile Pipe/Tubing Wire Coating Monofilament Extrusion Blow Molding Coating/Lamination Foam Coextrusion Reprocessing Information on Different Types of Extrusion Machines [INFOGRAPH]

From hardware and materials through processing and properties, this book presents a broad coverage of blown film extrusion and ensures a useful balance of theory and practice. This book explains certain effects in the blown film process so readers are better able to troubleshoot and improve their operations. Also, current practices and equipment are emphasized to keep readers up-to-date with the most productive and efficient technology. Companion CD: The Blown Film Extrusion Simulator enhances the learning process. This software was developed to teach blown film extrusion equipment operation and processing principles. The realistic graphic interface and intuitive operating techniques were designed to emulate processing methods so learners can quickly move from the simulator to real production equipment. Click here to download a free software demo. New to This Edition: Materials: Polyvinylidene Chloride (PVDC) Processing: Double Bubble Processing Product Applications: Breathable Packaging, Shrink Film, High Barrier Film Troubleshooting: Wrinkles Successful production of coextruded products depends on several key factors, including polymer selections, hardware design (screw, feedblock/die, handling equipment, layer construction and optimal processing conditions). Proper selection and adjustment of each factor will minimize difficulties and ensure high quality coextrusion results   Successful production of coextruded products depends on several key factors, including polymer selections, hardware design (screw, feedblock/die, handling equipment, layer construction and optimal processing conditions). Proper selection and adjustment of each factor will minimize difficulties and ensure high quality coextrusion results. Troubleshooting methods for coextrusion become increasingly complex as the number of layers in the structure increases, as the asymmetry of multi-layer con- struction grows, or as processing and rheological characteristics of coextruded materials differ greatly from one another. Understanding the problems associated with nonuniform layer distribution and interfacial instability between layers or on film surfaces is very important when troubleshooting the coextrusion process.     THE UNIFORMITY PROBLEM Nonuniform layer distribution is one of the more common problems encoun- tered in film coextrusion. This nonuniformity may appear in either the direction of extrusion or tangential to the direction of film production. Layer uniformity in the machine direction can be influenced by die imperfec- tions, poor die design or adjustment, excessive extruder pressure variation, variable film tension, or film bubble or web instability. Layer uniformity tangential to machine direction can be influenced by poor melt temperature uniformity, viscosity mismatch between layers, poor hardware design, or viscoelastic flow characteristics induced by excessive shear stress. Poor layer uniformity tangential to machine direction is caused by nonuniform melt temperature across a melt pipe, feedblock and/or die, as well as poor melt- ing in an extruder. Melt temperature variance alters viscosity uniformity, which exhibits a change in flow characteristics and layer distribution. Melt temperature of a single polymer stream can often vary by as much as 30°F. A general rule of thumb is to achieve ±2°F or less variation in melt temperature for each extruder. Homogenous melt temperatures can be achieved through installation of a static mixer in the melt pipe, a dynamic mixer on the extrusion screw or a more efficient screw design, or through adjustment of pipe, feedblock and/or die temperatures. Variation in the thickness of a film, which eventually reaches a steady-state condition of nonuniformity (assuming homogenous melt temperature conditions for each polymer), can be caused by a viscosity mismatch between layers. In a coextrusion system, lower-viscosity polymers migrate to the region of highest shear stress (nearest the die wall) and tend to encapsulate higher-viscosity poly- mers. The amount of migration is dependent on the degree of viscosity mismatch, the length of the flow path, and the shear stress in the system.     IMPROVING LAYER VARIATION Improvements in layer variations that are caused by viscosity-induced flow behavior can be achieved through adjustment of melt temperature, modification of distribution channels in the feedblock or die, or selection of a polymer with different viscosity characteristics which most commonly are measured by melt index. Also, annular dies typically are more tolerant of viscosity mismatch than flat-die systems.     1   Nonuniform layer distribution in the direction tangential to extrusion can also be caused by poor hardware design. Improperly designed flow channels of the feedblock or die can cause poor steady-state layer distribution of materials, even with the most closely matched viscosities. Nonuniform distribution of layers, in the form of parabolic flow lines, inter- mixing of layers, roughness between polymer boundaries, melt fracture, or uncharacteristically high haze, can be caused by interfacial instability between layers or on film surfaces. The instabilities are believed to be a result of the viscoelastic behavior of polymers at the die land or region of highest shear stress. Improvements in layer instabilities can be achieved by reducing the shear stress between coextrusion layers and/or the die-land surfaces. Shear stress can be reduced by decreasing total output rate, increasing skin-layer melt temperature (decrease in viscosity), increasing the die gap, adding a process lubricant to the skin material, or selecting a lower viscosity material. An increase in the thickness of the skin layer can also reduce instability between polymer layers by moving the interface further from the high-shear-stress die wall. This is especially significant for asymmetric coextrusion constructions. Finally, if coextrusion layers exhibit dramatic differences in melt elasticity, then choose materials that match more closely in extrudateMacbeth movie elasticity as measured by extrudateMacbeth movie swell.   TROUBLESHOOTING AT A GLANCE Problem: Lines in the film surface Possible cause: Die imperfections Solutions:

  • Clean die buildup
  • Remove contaminants from polymer melt channel
  • Repair die nicks and burrs

Problem: Gauge bands on film roll Possible cause: Poor die design Solutions:

  • Install spiral-channel die design to eliminate weld lines
  • Install rotating nip assembly in tower

Possible cause: Poor die adjustment Solutions:

  • Adjust concentricity of die gap
  • Center air ring in relation to die gap

Problem: Repeating pattern of variation in thickness of layer(s) Possible cause: Excessive extruder pressure variation (surging) Solutions:

  • Achieve ±1 percent or less variation in total head pressure for each extruder
  • Adjust extruder temperature profile (feed and transition zones)
  • Increase back pressure with restrictor flow plug
  • Increase back pressure by installing fine-mesh screen pack
  • Change screw design of surging extruder(s)
  • Check for worn screw(s) and replace if needed
  • Check extruder feedthroat(s) for bridging and correct if needed

Possible cause: Variable film tension Solution:

  • Eliminate variability in drive speed

Possible cause: Film bubble instability Solutions:

  • Protect bubble from atmospheric air turbulence
  • Correct pressure instability of air ring and/or internal air flow

2   Problem: Intermittent and somewhat random variation in thickness of layer(s) Possible cause: Poor melt temperature uniformity Solutions:

  • Achieve ±2°F or less variation in melt temperature for each extruder
  • Adjust extruder temperature profile to ensure complete melting of

extrudateMacbeth movie

  • Install new screw design with dynamic mixer for more efficient melting

capacity

  • Reduce screw speed for increased residence time to complete melting

of the polymer(s)

  • Adjust temperature of feed channels, die and/or feedblock

Problem: Variation in thickness of layer(s) that reaches steady-state distribution Possible cause: Viscosity mismatch of polymer layers Solutions:

  • Select polymers with matching viscosities
  • Adjust temperature of polymers to aid in matching viscosities

Possible cause: Poor hardware design Solution:

  • Change die and/or feedblock design

Problem: Uncharacteristically high film haze Possible cause: Viscoelastic flow characteristics induced by excessive shear stress between layers and/or feedblock/die surfaces Solutions:

  • Select lower-viscosity skin layer(s)
  • Increase melt temperature of skin-layer polymers
  • Increase die temperatures
  • Reduce total extrusion output
  • Increase die-gap opening
  • Add process lubricant to skin-layer polymer
  • Increase thickness of skin layers
  • Select polymer(s) that exhibit similar melt elasticity behavior

(extrudateMacbeth movie swell)   Problem: Parabolic-shaped flow lines in direction of extrusion Possible cause: Same as for uncharacteristically high, film-haze problem Solution:

  • Same as for uncharacteristically high, film-haze problem

Problem: Intermixing of polymer layers Possible cause: Same as for uncharacteristically high, film-haze problem Solution:

  • Same as for uncharacteristically high, film-haze problem

Problem: Roughness between polymer-layer boundaries Possible cause: Same as for uncharacteristically high, film-haze problem Solution:

  • Same as for uncharacteristically high, film-haze problem

Problem: Melt fracture of film surface Possible cause: Same as for uncharacteristically high, film-haze problem Solution: • Same as for uncharacteristically high, film-haze problem 2layer03 https://www.youtube.com/watch?v=ZJ4T36QQRlk Coextrusion Processing Defined The conversion of multiple thermoplastics, flowing through separate streams, that are combined into a common primary passage and then shaped by a die. Multiple layers provide properties that cannot be provided by a single material for high barrier coextrusion processing. The main classes are: film; sheet; tubing; coating; and blowmolded shapes.FILM COEXTRUSION: A Troubleshooting Guide 03 Successful Production of Coextruded Products Depends on Three Key Factors 1. Polymer Selections 2. Design of Hardware Screws, Feedblock/Die, Handling 3. Coextrusion Layer Construction 4. Optimal Processing ConditionsFILM COEXTRUSION: A Troubleshooting Guide 04 Layer Uniformity is Influenced by: • Variations in extrusion pressure • Nominal extrusion melt temperature • Viscosity-induced web flow • Bubble or melt instability • Variable film tension • Poor die design or improper adjustment • Die imperfections or contaminants Interfacial Flow Instability is Caused by: • Interfacial critical shear stressFILM COEXTRUSION: A Troubleshooting Guide 05 Extrusion Pressure Variations Variation in extrusion pressure, often referred to as surging, is directly related to feeding stability of an extruder. Improving layer uniformity caused by pressure variation can be achieved through: • Adjustment of back pressure – Screenback – Restrictor flow plug • Extrusion screw design of feed and transition sections • Adjustment of extrusion screw-temperature profile • Prevent polymer bridging in feedthroat • Replace/repair worn extrusion screwFILM COEXTRUSION: A Troubleshooting Guide 06 Head Pressure Trace 0 15 30 45 60 75 90 105 120 TIME (seconds) 1850 1840 1830 1820 1810 1800 1790 1780 1770 1760 1750 HEAD PRESSURE 1805 1795 1785 1775 1765 1755 1745 1734 1725 1715 1705 HEAD PRESSUREFILM COEXTRUSION: A Troubleshooting Guide 07 Layer Thickness Instability Caused by Pressure Variation FLOW DIRECTION STABLE FLOW Uniform thickness ONSET OF INSTABILITY Small gauge variation SEVERE INSTABILITY Large gauge variationFILM COEXTRUSION: A Troubleshooting Guide 08 Extrusion Flange Back Pressure Adjustment ADJUSTABLE VALVE INSTRUMENT PORTFILM COEXTRUSION: A Troubleshooting Guide 09 Typical Arrangement of Coarse and Fine Screens Between the Screw and Breaker Plate BREAKER PLATE COARSE SCREEN FINE SCREENS COARSE SCREEN RESIN FLOWFILM COEXTRUSION: A Troubleshooting Guide 10 Melt Temperature Variations Nonuniform melt temperature across a melt pipe, as well as poor polymer melting in an extruder, cause poor layer uniformity. Homogenous polymer melt temperatures can be achieved through: • Static and/or dynamic mixers • Adjustment of pipe and die temperatures • Adjustment of extrusion screw temperature profile • Replace/repair worn extrusion screwFILM COEXTRUSION: A Troubleshooting Guide 11 Melt Thermocouple Trace 0 15 30 45 60 75 90 105 120 TIME (seconds) 380 358 356 354 352 350 348 346 344 342 340 MELT TEMPERATURE 380 358 356 354 352 350 348 346 344 342 340 MELT TEMPERATUREFILM COEXTRUSION: A Troubleshooting Guide 12 414° 410° 406° 402° 398° °F 394° 390° 386° 382° 378° 374° 0 1/8 1/4 3/8 1/2 5/8 3/4 7/8 0 BARREL WALL BARREL CENTER LINE BARREL WALL Typical Temperature Profile of Polymer Melt Stream in PipeFILM COEXTRUSION: A Troubleshooting Guide 13 Layer Thickness Instability Caused by Nonuniform Melt Temperature FLOW DIRECTION STABLE FLOW Uniform thickness ONSET OF INSTABILITY Small gauge variation SEVERE INSTABILITY Large gauge variationFILM COEXTRUSION: A Troubleshooting Guide 14 Infographic- How does a blown film line and blown film plant is Better 2014-01-24 11-39-57 Coextrusion Processing Defined The conversion of multiple thermoplastics, flowing through separate streams, that are combined into a common primary passage and then shaped by a die. Multiple layers provide properties that cannot be provided by a single material for high barrier coextrusion processing. The main classes are: film; sheet; tubing; coating; and blowmolded shapes.FILM COEXTRUSION: A Troubleshooting Guide 03 Successful Production of Coextruded Products Depends on Three Key Factors 1. Polymer Selections 2. Design of Hardware Screws, Feedblock/Die, Handling 3. Coextrusion Layer Construction 4. Optimal Processing ConditionsFILM COEXTRUSION: A Troubleshooting Guide 04 Layer Uniformity is Influenced by: • Variations in extrusion pressure • Nominal extrusion melt temperature • Viscosity-induced web flow • Bubble or melt instability • Variable film tension • Poor die design or improper adjustment • Die imperfections or contaminants Interfacial Flow Instability is Caused by: • Interfacial critical shear stressFILM COEXTRUSION: A Troubleshooting Guide 05 Extrusion Pressure Variations Variation in extrusion pressure, often referred to as surging, is directly related to feeding stability of an extruder. Improving layer uniformity caused by pressure variation can be achieved through: • Adjustment of back pressure – Screenback – Restrictor flow plug • Extrusion screw design of feed and transition sections • Adjustment of extrusion screw-temperature profile • Prevent polymer bridging in feedthroat • Replace/repair worn extrusion screwFILM COEXTRUSION: A Troubleshooting Guide 06 Head Pressure Trace 0 15 30 45 60 75 90 105 120 TIME (seconds) 1850 1840 1830 1820 1810 1800 1790 1780 1770 1760 1750 HEAD PRESSURE 1805 1795 1785 1775 1765 1755 1745 1734 1725 1715 1705 HEAD PRESSUREFILM COEXTRUSION: A Troubleshooting Guide 07 Layer Thickness Instability Caused by Pressure Variation FLOW DIRECTION STABLE FLOW Uniform thickness ONSET OF INSTABILITY Small gauge variation SEVERE INSTABILITY Large gauge variationFILM COEXTRUSION: A Troubleshooting Guide 08 Extrusion Flange Back Pressure Adjustment ADJUSTABLE VALVE INSTRUMENT PORTFILM COEXTRUSION: A Troubleshooting Guide 09 Typical Arrangement of Coarse and Fine Screens Between the Screw and Breaker Plate BREAKER PLATE COARSE SCREEN FINE SCREENS COARSE SCREEN RESIN FLOWFILM COEXTRUSION: A Troubleshooting Guide 10 Melt Temperature Variations Nonuniform melt temperature across a melt pipe, as well as poor polymer melting in an extruder, cause poor layer uniformity. Homogenous polymer melt temperatures can be achieved through: • Static and/or dynamic mixers • Adjustment of pipe and die temperatures • Adjustment of extrusion screw temperature profile • Replace/repair worn extrusion screwFILM COEXTRUSION: A Troubleshooting Guide 11 Melt Thermocouple Trace 0 15 30 45 60 75 90 105 120 TIME (seconds) 380 358 356 354 352 350 348 346 344 342 340 MELT TEMPERATURE 380 358 356 354 352 350 348 346 344 342 340 MELT TEMPERATUREFILM COEXTRUSION: A Troubleshooting Guide 12 414° 410° 406° 402° 398° °F 394° 390° 386° 382° 378° 374° 0 1/8 1/4 3/8 1/2 5/8 3/4 7/8 0 BARREL WALL BARREL CENTER LINE BARREL WALL Typical Temperature Profile of Polymer Melt Stream in PipeFILM COEXTRUSION: A Troubleshooting Guide 13 Layer Thickness Instability Caused by Nonuniform Melt Temperature FLOW DIRECTION STABLE FLOW Uniform thickness ONSET OF INSTABILITY Small gauge variation SEVERE INSTABILITY Large gauge variationFILM COEXTRUSION: A Troubleshooting Guide 14 Adjustable Depth Prob