https://www.avient.com/sites/default/files/2025-02/Hexagon and digimat case study.pdf
In Figure 4, the failure location between the isotropic
modelling approach and the Digimat anisotropic modelling
approach is identical.
In Figure 6, the failure locations in the tensile tests are
shown for the isotropic and Digimat anisotropic modelling
approaches respectively.
As opposed to the isotropic
approach, the Digimat anisotropic approach correctly
captures the experimentally observed failure location.
https://www.avient.com/sites/default/files/2020-09/stat-tech-tri-fold-processing-guide.pdf
Gate type
should be selected based on location and part geometry
PROBLEM CAUSE SOLUTION
Incomplete Fill Melt and/or mold
temperature too cold
Mold design
Shot Size
• Increase nozzle and barrel temperatures
• Increase mold temperature
• Increase injection speed
• Increase pack and hold pressure
• Increase nozzle tip diameter
• Check thermocouples and heater bands
• Enlarge or widen vents and increase number of vents
• Check that vents are unplugged
• Check that gates are unplugged
• Enlarge gates and/or runners
• Perform short shots to determine fill pattern and verify
proper vent location
• Increase wall thickness to move gas trap to parting line
• Increase shot size
• Increase cushion
Brittleness Melt temperature too low
Degraded/Overheated material
Gate location and/or size
• Increase melt temperature
• Increase injection speed
• Measure melt temperature with pyrometer
• Decrease melt temperature
• Decrease back pressure
• Use smaller barrel/excessive residence time
• Relocate gate to nonstress area
• Increase gate size to allow higher flow speed
and lower molded-in stress
Fibers on Surface
(Splay)
Melt temperature too low
Insufficient packing
• Increase melt temperature
• Increase mold temperature
• Increase injection speed
• Increase pack and hold pressure, and time
• Increase shot size
• Increase gate size
Sink Marks Part geometry too thick
Melt temperature too hot
Insufficient material volume
• Reduce wall thickness
• Reduce rib thickness
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Increase shot size
• Increase injection rate
• Increase packing pressure
• Increase gate size
Flash Injection pressure too high
Excess material volume
Melt and/or mold
temperature too hot
• Decrease injection pressure
• Increase clamp pressure
• Decrease injection speed
• Increase transfer position
• Decrease pack pressure
• Decrease shot size
• Decrease injection speed
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Decrease screw speed
TROUBLESHOOTING RECOMMENDATIONS
PROBLEM CAUSE SOLUTION
Excessive Shrink Too much orientation • Increase packing time and pressure
• Increase hold pressure
• Decrease melt temperature
• Decrease mold temperature
• Decrease injection speed
• Decrease screw rpm
• Increase venting
• Increase cooling time
Not Enough Shrink Too little orientation • Decrease packing pressure and time
• Decrease hold pressure
• Increase melt temperature
• Increase mold temperature
• Increase injection speed
• Increase screw rpm
• Decrease cooling time
Burning Melt and/or mold
temperature too hot
Mold design
Moisture
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Decrease injection speed
• Clean, widen and increase number of vents
• Increase gate size or number of gates
• Verify material is dried at proper conditions
Nozzle Drool Nozzle temperature too hot • Decrease nozzle temperature
• Decrease back pressure
• Increase screw decompression
• Verify material has been dried at proper conditions
Weld Lines Melt front temperatures
too low
Mold design
• Increase pack and hold pressure
• Increase melt temperature
• Increase vent width and locations
• Increase injection speed
• Increase mold temperature
• Decrease injection speed
• Increase gate size
• Perform short shots to determine fill pattern and verify
proper vent location
• Add vents and/or false ejector pin
• Move gate location
Warp Excessive orientation
Mold design
• Increase cooling time
• Increase melt temperature
• Decrease injection pressure and injection speed
• Increase number of gates
Sticking in Mold Cavities are overpacked
Mold design
Part is too hot
• Decrease injection speed and pressure
• Decrease pack and hold pressure
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Increase cooling time
• Increase draft angle
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Increase cooling time
TROUBLESHOOTING RECOMMENDATIONS
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Copyright © 2020, Avient Corporation.
https://www.avient.com/sites/default/files/2020-12/therma-tech-processing-guide.pdf
Gate type should be selected based on location and
part geometry.
2.
Maintain a minimum draft angle of 1° per side.
4 Therma-Tech
Troubleshooting Recommendations
Problem Cause Solution
Incomplete Fill
Melt and/or mold
too cold
• Increase nozzle and barrel temperatures
• Increase mold temperature
• Increase injection rate
• Increase pack and hold pressure
• Increase nozzle tip diameter
• Check thermocouples and heater bands
Mold design
• Enlarge or widen vents and increase number of vents
• Check that vents are unplugged
• Check that gates are unplugged
• Enlarge gates and/or runners
• Perform short shots to determine fill pattern and
verify proper vent location
• Increase wall thickness to move gas trap to
parting line
Shot size
• Increase shot size
• Increase cushion
• Decrease transfer position
Brittleness
Low melt
temperature
• Increase melt temperature
• Increase injection rate
• Measure melt temperature with pyrometer
Degraded/
overheated
material
• Decrease melt temperature
• Decrease back pressure
• Use smaller barrel/excessive residence time
• Decrease screw rpm
Gate location
and/or size
• Relocate gate to nonstress area
• Increase gate size to allow higher flow rate and lower
molded in stress
Fibers on Surface
(Splay)
Melt temperature
too low
• Increase melt temperature
• Increase mold temperature
• Increase injection speed
• Increase screw rpm
Insufficient packing
• Increase pack and hold pressure, and time
• Increase shot size
• Increase gate size
Processing Guide 5
Problem Cause Solution
Sink Marks
Part geometry
too thick
• Reduce wall thickness
• Reduce rib thickness
• Maintain nominal wall thickness
Melt too hot • Decrease nozzle and barrel temperatures• Decrease mold temperature
Insufficient
material volume
• Increase shot size
• Increase injection rate
• Increase pack pressure/time
• Increase gate size
Flash
Injection pressure
too high
• Decrease injection pressure
• Increase clamp pressure
• Decrease injection rate
• Increase transfer position
Excess
material volume
• Decrease pack pressure
• Decrease shot size
• Decrease injection rate
Melt and/or mold
too hot
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Decrease screw speed
Excessive Shrink Too much orientation
• Increase packing time and pressure
• Increase hold pressure
• Decrease melt temperature
• Decrease mold temperature
• Decrease injection speed
• Decrease screw rpm
• Increase venting
• Increase cooling time
Not Enough Shrink Too little orientation
• Decrease packing pressure and time
• Decrease hold pressure
• Increase melt temperature
• Increase mold temperature
• Increase injection speed
• Increase screw rpm
• Decrease cooling time
Troubleshooting Recommendations
6 Therma-Tech
Troubleshooting Recommendations
Problem Cause Solution
Burning
Melt and/or mold
too cold
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Decrease injection rate
Mold design • Clean, widen and increase number of vents• Increase gate size or number of gates
Moisture • Verify material is dried at proper conditions
Nozzle Drool Nozzle temperature too hot
• Decrease nozzle temperature
• Decrease back pressure
• Increase screw decompression
• Verify material has been dried at proper conditions
Weld Lines
Melt front temperatures
are too low
• Increase pack and hold pressure
• Increase melt temperature
• Increase vent width and locations
• Increase injection rate
• Increase mold temperature
Mold design
• Decrease injection rate
• Increase gate size
• Perform short shots to determine fill pattern
and verify proper vent location
• Add vents and/or false ejector pin
• Move gate location
Warp
Excessive orientation
• Increase cooling time
• Increase melt temperature
• Decrease injection pressure and injection rate
Mold design • Increase number of gates
Sticking in Mold
Cavities are
overpacked
• Decrease injection rate and pressure
• Decrease pack and hold pressure
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Increase cooling time
Mold design • Increase draft angle
Part is too hot
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Increase cooling time
1.844.4AVIENT
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Copyright © 2020, Avient Corporation.
https://www.avient.com/sites/default/files/2022-06/Nymax BIO Bio-based Polyamide Solutions Processing Guide.pdf
Decrease injection speed
Gate location
and/or size
1.
Increase vent width and locations
4.
Identify end of fill pattern and verify proper vent location
3.
https://www.avient.com/sustainability-2020
Each assessment considers geographic location, relationships with communities and applicable laws.
In higher-risk locations, we maintain detailed security preparedness plans.
https://www.avient.com/sites/default/files/2022-06/Maxxam FR Injection Molding Processing Guide.pdf
Gate type should be selected based on location and part geometry
Vents should be placed at the intersection of each 90° bend in the runner
system off of the cold slug well and vented to atmosphere
PROBLEM CAUSE SOLUTION
Black Specks
Contamination
• Purge barrel with general purpose PP
• Verify correct nozzle is being used
• Pull screw for cleaning
Degraded/overheated
material
• Decrease melt temperature
• Decrease back pressure
• Decrease injection speed
• Use appropriately sized barrel
Brittleness
Degraded/overheated material
• Decrease melt temperature
• Decrease back pressure
• Decrease injection speed
• Use appropriately sized barrel
Gate location and/or size
• Relocate gate to nonstress area
• Increase gate size to allow higher flow rate and
lower molded-in stress
Burning
Process related
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Decrease injection rate
Mold design
• Clean, widen and increase number of vents
• Increase gate size to reduce shear
Fibers/Minerals on
Surface or Uneven
Surface Appearance
Melt temperature too low
• Increase melt temperature
• Increase mold temperature
• Increase injection speed
Insufficient packing
• Increase hold pressure and time
• Increase shot size
Flash
Injection pressure
too high
• Decrease injection pressure
• Increase clamp pressure
• Decrease injection rate
• Increase transfer position
Excess material volume
• Adjust transfer position
• Decrease pack pressure
• Decrease shot size
• Decrease injection rate
Melt and/or mold too hot
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Decrease screw speed
Loose clamp
• Reset mold height
• Increase clamp tonnage
Troubleshooting Recommendations
PROBLEM CAUSE SOLUTION
Incomplete Fill
Melt and/or mold too cold
• Increase nozzle and barrel temperatures
• Increase mold temperature
• Increase injection rate
Mold design
• Enlarge or widen vents and increase number
of vents
• Check that vents are unplugged
• Check that gates are unplugged
• Enlarge gates and/or runners
• Perform short shots to determine fill pattern
and verify proper vent location
• Increase wall thickness to move gas trap to
parting line
Shot size
• Adjust transfer position to 98% full
• Increase shot size
Nozzle Drool Nozzle temperature too hot
• Decrease nozzle temperature
• Decrease back pressure
• Increase screw decompression
Shrink
Too much shrink
• Increase cooling time
• Decrease mold temperature
Too little shrink
• Decrease cooling time
• Increase mold temperature
Sink Marks
Part geometry too thick
• Reduce wall thickness
• Reduce rib thickness
Melt too hot
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
Insufficient material
volume
• Adjust transfer position
• Increase shot size
• Increase injection rate
• Increase packing pressure
Troubleshooting Recommendations (continued)
PROBLEM CAUSE SOLUTION
Sticking in Mold
Overfilled cavity
• Decrease injection rate and pressure
• Decrease hold pressure
• Adjust transfer position
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Decrease cooling time
Mold design
• Increase draft angle
• Polish cores in direction of ejection
Part is too hot
• Decrease nozzle and barrel temperatures
• Decrease mold temperature
• Increase cooling time
Warp
Process related
• Increase cooling time
• Increase melt temperature
• Increase pack pressure
• Increase pack time
• Decrease mold temperature
Mold design • Inspect for non-uniform mold cooling
Part design • Inspect for non-uniform wall thickness
Temperature control unit
incorrect temperature
• Check settings
• Inspect thermocouple
Weld Lines
Melt front temperatures
are too low
• Increase pack and hold pressure
• Increase melt temperature
• Increase injection rate
• Increase mold temperature
Mold design
• Increase gate size
• Perform short shots to determine fill pattern
and verify proper vent location
• Add vents and/or false ejector pin
• Move gate location
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Copyright © 2022, Avient Corporation.
https://www.avient.com/sites/default/files/2023-08/CSP registration supplier guide.pdf
➢ Please check the three boxes for: Invoice- from location, Pay to location and Ship from
location
https://www.avient.com/sites/default/files/2020-10/2020-gravi-tech-processing-guide.pdf
Increase vent width and locations
4.
Increase/Decrease mold temperature
Gate Size/Location
1.
Change gate location
Voids
Insufficient packing
pressure
1.
https://www.avient.com/sites/default/files/2020-10/tpe-injection-molding-guide.pdf
The gate location
is equally important.
They are located along the tool parting line.
Locating the gate at the top of the part
minimizes this problem.
https://www.avient.com/sites/default/files/2024-10/Avient CDP Climate Change %26 Water Submission 20241001.pdf
Fixed row]
(2.3) Have you identified priority locations across your value chain?
2.3.1) Identification of priority locations
Select from:
☑ Yes, we have identified priority locations
(2.3.2) Value chain stages where priority locations have been identified
Select all that apply
☑ Direct operations
(2.3.3) Types of priority locations identified
Sensitive locations
☑ Areas important for biodiversity
☑ Areas of limited water availability, flooding, and/or poor quality of water
(2.3.4) Description of process to identify priority locations
Avient uses the WRI Aqueduct tool and WWF Biodiversity tool to identify sites with high water and biodiversity risks
(2.3.5) Will you be disclosing a list/spatial map of priority locations?
Select all that apply
☑ No
[Fixed row]
(7.3) Describe your organization’s approach to reporting Scope 2 emissions.
148
Scope 2, location-based Scope 2, market-based Comment
Select from:
☑ We are reporting a Scope 2,
location-based figure
Select from:
☑ We are reporting a Scope 2,
market-based figure
We are reporting location and market based emissions; both
numbers have been assured.