https://www.avient.com/sites/default/files/2020-10/luxury-closures-gravi-tech-design-guide-2.0-application-specific.pdf
This adhesive is not very chemically resistant,
and has lower strength properties.
14 Gravi-Tech
CHAPTER 4 | MOLD DESIGN GUIDELINES
COLD RUNNER LAYOUTS
Herringbone (Fishbone) Runner
This type of runner has an unbalanced fill, which
can be artificially balanced by adjusting runner
sizes.
Design Guide 33
Mold damages Loss of clamp force
Barrel malfunction
Melt temperature
Injection speed
Transfer position
Excessive pack
Excessive back
Repair mold damage
Clean parting line
Reduce pinch-off land
Increase clamp force Dry material Reduce melt
Reduce mold
Reduce hold pressure
Increase transfer
Flash
• Excess material commonly found at parting lines or mold features
Root cause: Too much plastic or mold damage.
34 Gravi-Tech
Design of gate too small or
in wrong
location
Machine not providing
Heater overriding
Viscosity too low
Injection velocity
too high
Melt temperature
Remove sharp corners from
Change gate type
Move gate to a position
where the melt stream
will impinge upon a mold
feature
Dry material Reduce injection
Increase melt
Jetting
Root cause: Injection speed is too high for the viscosity of the material
Design Guide 35
Finish too rough
Screw configuration
Overworking material
Non-compatible
additive
Melt temperature too high
Remove sharp corners from
Use smaller screw/barrel
Check melt uniformity
Check L/D ratio
Check additive
compatibility
Reduce melt
Reduce screw speed
Reduce residence time
Plate-Out
• Build-up or deposit on mold surface
Root cause: One component of the material is not totally compatible.
36 Gravi-Tech
Shut-off partially turned
Screw problems
Barrel heater problems
Material too dry
Under-packing
Not enough pack
Melt temperature
Transfer position
Make sure gate is not
blocked
Insure runner shut-off
is not turned
Check venting
Change gating location
Add flow leader
Insure cushion position
Make sure screw is transfer-
ring at a correct
Change screw/barrel
Make sure material was
dried at proper settings
Increase melt
Increase mold
Decrease transfer
Short Shot
• Not enough material is being injected into the mold to fill out all of the cavities
Root cause: Not enough plastic is getting into the cavity.
End of Fill
Part Length
Dynamic Pressure
Hydrostatic Pressure
P
ss
Gate End Part
FIGURE 61 - Deflection Equations
H
F
WLMax Deflection:
0.002" (0.05mm)
1 = W • H3
12
_______
bending = F • L3
48 • E • I
_______
k
Vcoolant
nmax, coolant
• Pcoolant • Cp, coolant
Dmin =
k
Vcoolant
nmax, coolant
• Pcoolant • Cp, coolant
Dmin =
k
Vcoolant
nmax, coolant
• Pcoolant • Cp, coolant
Dmin =
FIGURE 60 - Pressure vs Part Length
FIGURE 61 - Deflection equations
FIGURE 62 - For Plate Shaped Parts
FIGURE 63 - For Cylindrical Shaped Parts
Design Guide 49
• MMoldings = Combined mass of molded parts
• Cp = Specific Heat of the material
Step 3 – Heat Removal Rate
• Nlines = The total number of independent
cooling lines there are in the mold
• tc = The cooling time required by the part
(Determined in step 1)
Step 4 – Coolant Volumetric Flow Rate
• ΔTMax,Coolant = Change in coolant
Temperature During Molding (1°C)
• ρCoolant = Density of coolant
• CP = Specific heat of coolant
Step 5 – Determine Cooling Line Diameter
• ρCoolant = Density of coolant
• VCoolant = Volumetric flow rate of coolant
• μCoolant = Viscosity of coolant
• ΔPline = Max pressure drop per line
(Usually equals half of the pump capacity)
• LLine = Length of the cooling lines
COOLING LINE SPACING
k
Vcoolant
nmax, coolant
• Pcoolant • Cp, coolant
Dmin =
k
Vcoolant
nmax, coolant
• Pcoolant • Cp, coolant
Dmin =
k
Vcoolant
nmax, coolant
• Pcoolant • Cp, coolant
Dmin =
k
Vcoolant
nmax, coolant
• Pcoolant • Cp, coolant
Dmin =
k
Vcoolant
nmax, coolant
• Pcoolant • Cp, coolant
Dmin =
k
Vcoolant
nmax, coolant
• Pcoolant • Cp, coolant
Dmin =
2D < H
< 5D
H
< W
< 2H
FIGURE 70 - Cooling Line Spacing
FIGURE 64 - Heat Transfer Equation
FIGURE 65 - Total Cooling for Mold
FIGURE 66 - Cooling Required by Each Line
FIGURE 68 - Max Diameter Equation
FIGURE 69 - Min Diameter Equation
FIGURE 67 - Volumetric Flow Rate Equation
50 Gravi-Tech
ADHESIVE ADVANTAGES DISADVANTAGES
Cyanoacrylate
Rapid, one-part process
Various viscosities
Can be paired with primers
for polyolefins
Poor strength
Low stress crack resistance
Low chemical resistance
Epoxy
High strength
Compatible with various
substrates
Tough
Requires mixing
Long cure time
Limited pot life
Exothermic
Hot Melt
Solvent-free
High adhesion
Different chemistries for
different substrates
High temp dispensing
Poor high temp performance
Poor metal adhesion
Light Curing Acrylic
Quick curing
One component
Good environmental resistance
Oxygen sensitive
Light source required
Limited curing configurations
Polyurethane
High cohesive strength
Impact and abrasion resistance
Poor high heat
performance
Requires mixing
Silicone
Room temp curing
Good adhesion
Flexible
Performs well in high temps
Low cohesive strength
Limited curing depth
Solvent sensitive
No-Mix Acrylic
Good peel strength
Fast cure
Adhesion to variety
of substrates
Strong odor
Exothermic
Limited cure depth
Design Guide 51
Bibliography
1.
https://www.avient.com/sites/default/files/resources/FAQs%2520for%2520PolyOne%2520GHS%2520Requirements%2520Ver%252006%2520April%25202015.pdf
Broadly, the HCS covers how
chemical manufacturers must determine and communicate the hazards of their products.
European countries must also start using the new overall format for chemical mixtures (most of
PolyOne’s products and solutions are considered mixtures).
Additionally, GHS changes the basic
way in which the hazards of a chemical or mixture of chemicals are determined by comparison against
specific criteria and providing a prescribed approach to determine hazard classifications and levels of
severity.
https://www.avient.com/sites/default/files/2022-07/ECCOH_ 5970 - Thin FTTH Cables - Application Snapshot.pdf
EUROPEAN CABLE
MANUFACTURER
J A C K E T F O R T H I N F T T H
C A B L E S
• FTTH jacket material for cables installed in premises
where no duct and little space is available
• Superior crush resistance for small diameter cables
• UV and chemical resistance including solvents, oil, acid
and bases
• Utilized formulation expertise to provide a solution
with the desired combination of performance
characteristics
• Provided superior UV and chemical resistance,
increasing cable lifetime
• Reduced attenuation loss due to better crush
resistance
• Enabled the required flexibility and reduced cable
weight
ECCOH™ 5970 Formulation
KEY REQUIREMENTS
WHY AVIENT?
AVIENT SOLUTION
CHEMICAL + UV RESISTANCE
LEARN MORE
Copyright © 2022, Avient Corporation.
https://www.avient.com/sites/default/files/2022-07/ECCOH_ 5702 SEPAP - Riser Cables - Applications Snapshot.pdf
CABLE
MANUFACTURER
H I G H F L A M E R E T A R D A N T
S H E A T H F O R R I S E R C A B L E S
• Fire performance: CPR classification Dca s1 a1 d0 at a
thickness of 350µm
• Low shrinkage
• Water, UV and chemical resistance
• Low CoF
• Reduced cable weight by decreasing the jacket
thickness from 550µm to 350µm
• Provided required CPR classification at a reduced
thickness allowing installation in homes and
buildings in between walls and floors
• Increased cable lifetime due to improved
chemical and UV resistance
• Enabled fast cable processing
ECCOH™ 5702 SEPAP Formulation
KEY REQUIREMENTS
WHY AVIENT?
AVIENT SOLUTION
LIGHTHWEIGHT + UV/CHEMICAL RESISTANCE
LEARN MORE
Copyright © 2022, Avient Corporation.
https://www.avient.com/sites/default/files/2024-10/ECCOH_ 5702 SEPAP Formulation - Shealth for Riser Cable - Application Snapshot.pdf
CABLE
MANUFACTURER
F L A M E - R E T A R D A N T S H E A T H
F O R R I S E R C A B L E S
• Fire performance: CPR classification Dca s1 a1 d0 at a
thickness of 350µm
• Low shrinkage
• Water, UV, and chemical resistance
• Low coefficient of friction (CoF)
• Reduced overall cable weight cable by
reducing the jacket thickness from 550µm to
350µm
• Increased the lifetime value of the cable by
providing superior chemical and UV resistance
• Provided low CoF on the inner layer, making
the solution suitable for use with micro ducts
as it’s easier to blow cables inside
ECCOH LSFOH 5702 SEPAP Formulation
KEY REQUIREMENTS
WHY AVIENT?
AVIENT SOLUTION
UV + CHEMICAL RESISTANCE
LEARN MORE
© 2024 Avient Corporation, All Rights Reserved
https://www.avient.com/products/engineered-polymer-formulations/sustainable-formulations/eccoh-low-smoke-and-fume-non-halogen-formulations
Cable Manufacturer
https://www.avient.com/sites/default/files/2023-06/Trilliant HC-auto-injector-snapshot.pdf
MEDICAL CONTRACT
MANUFACTURER
A U T O - I N J E C T O R H O U S I N G
• Excellent chemical and wear resistance
• Excellent impact resistance
• Specific color matching based on customer’s needs
• Outstanding durability to extend product life
• Customized a chemically resistant formulation
to offer an impact-modified alternative to
traditional competitors in the market
• Provided technical support for material
selection, part & tool design, and process
development to accelerate commercialization
• Delivered custom color matching to meet all
key requirements
Custom Trilliant™ HC Healthcare Thermoplastic
KEY REQUIREMENTS
WHY AVIENT?
https://www.avient.com/products/engineered-polymer-formulations/chemical-corrosion-resistant-formulations/trilliant-hc-healthcare-thermoplastics
https://www.avient.com/sites/default/files/2021-05/say-eng-lee.pdf
He has more than 35 years of experience in the Chemicals industry.
Hanna Company and
Dainippon Ink & Chemicals INC., Japan.
He holds a bachelor’s of science in Chemical Engineering from the National Cheng Kung
University in Taiwan.
https://www.avient.com/sites/default/files/2024-12/Say-Eng Lee Bio.pdf
He has more than 35 years of experience in the Chemicals industry.
Hanna Company and
Dainippon Ink & Chemicals INC., Japan.
He holds a Bachelor of Science in Chemical Engineering from the National Cheng Kung
University in Taiwan.
https://www.avient.com/sites/default/files/2024-03/Alternatives to Nylon 6_6 Brochure %281%29.pdf
HOW ALTERNATIVE
POLYMERS COMPARE
TO PA 6,6
PA 6 | POSSIBLE APPLICATIONS:
Automotive, Industrial, Consumer & Sporting Goods
Wider processing temperature range
Better surface quality
Better weathering resistance
Shorter conditioning time—nearly half that of PA 6,6
Lower temperature resistance
Slightly lower chemical resistance
Higher water absorption
Lower stiffness/wear resistance
PK | POSSIBLE APPLICATIONS:
Automotive, Consumer & Sporting Goods, Industrial,
Electrical & Electronics
Lower CO2 emissions in production
Better hydrolysis and chemical resistance
Comparable dimensional stability
Inherently lubricious for reduced wear and friction
Easier to mold
Cost competitive
Lower short- and long-term thermal performance
Harder to color
More limited process window
PBT/PET | POSSIBLE APPLICATIONS:
Electrical & Electronics
Lower water absorption
Slightly higher rigidity/stiffness (for PBT)
Better abrasion resistance
Slightly better electric resistance
Lower toughness properties
Higher density
Lower short- and long-term temperature resistance
Lower hydrolysis resistance
PP | POSSIBLE APPLICATIONS:
Automotive, Consumer Goods,
Lightweighting Applications
Lower water absorption
Slightly better chemical resistance
Lower density
Cost effective
Fiber reinforced PP can achieve similar or
better mechanical properties to PA 6,6 GF30
Reduced rigidity/stiffness
Much lower abrasion resistance
Lower electric resistance
Reduced short- and long-term temperature
resistance
PC/PBT & PC/PET BLENDS |
POSSIBLE APPLICATIONS: Automotive Interiors,
Consumer Goods, Household Appliances
Higher impact strength
Good scratch resistance
Good wear resistance
Lower mechanical properties
Higher brittleness
Narrow processing temperature range
PA 6,6/PET BLENDS |
POSSIBLE APPLICATIONS: Automotive, Industrial,
Appliance, Electrical & Electronics, Applications Where
Low Water Absorption is Required
Reduced water absorption—up to 40%
Slightly higher mechanical properties in the conditioned state
Slightly lower temperature resistance
Slightly lower chemical resistance
Narrow processing temperature range
PA/PP BLENDS | POSSIBLE APPLICATIONS:
Automotive Interiors, Electronics,
Consumer & Sporting Goods
Good adhesion to polyolefin-based TPEs
Low permeability of water
Good processability
Lower density
Lower temperature resistance
Lower mechanical properties
POST-INDUSTRIAL RECYCLED SOLUTIONS
(PA 6,6/PA 6/PP) |
POSSIBLE APPLICATIONS: Automotive Accessories,
Industrial, Consumer & Sporting Goods
Between 50-80% recycled content
Good processability
Cost effective
Reduced chemical resistance
Wider range of mechanical specifications
Potential for slightly lower mechanical properties
1.844.4AVIENT
www.avient.com
Copyright © 2024, Avient Corporation.
https://www.avient.com/sites/default/files/2021-03/lubrione-pke-product-bulletin.pdf
These grades combine excellent
chemical resistance and dimensional stability with
improved wear resistance and low coefficient of
friction (COF) properties.
KEY CHARACTERISTICS
• Inherently low COF
• Excellent wear resistance
• Excellent chemical resistance
• Low moisture uptake
• Excellent dimensional stability
• Cost-effective
• Eco-conscious alternative to PA66,
PA6 and POM
MARKETS & APPLICATIONS
These materials are ideal for use in applications
requiring lubricated solutions, as the formulations
have improved wear, chemical, and hydrolysis
resistance over nylons (PA6 or PA66).
LubriOne
PKE formulations also offer improved chemical
resistance and thermal performance, plus reduced
flammability, over POM