Plastic Product Design
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Plastic Product Design. SARATH BABU MADDUKURI. Over View of Plastic Product Design Polymer Fundamentals Plastic Product Design Steps Plastic Material Selection Process Plastic Product Design Guidelines Plastic Manufacturing Process Basics of Injection Mold. Index.

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Plastic product design

Plastic Product Design

SARATH BABU MADDUKURI


Index

Over View of Plastic Product Design

Polymer Fundamentals

Plastic Product Design Steps

Plastic Material Selection Process

Plastic Product Design Guidelines

Plastic Manufacturing Process

Basics of Injection Mold

Index


Plastic product design

Product Design Environment


Plastic product design

Product Design & Development Steps

  • End Use Requirement

  • a) Anticipated Structural Requirement

  • Loads- Stresses a material will be subjected

  • Rate of Loading

  • Duration of Loading

  • Impact Forces

  • Vibration

  • Foreseeable Misuse

  • b) Anticipated Environment

  • Temp Extremes

  • c) Assembly and Secondary Operation

  • d) Cost Limits

  • e) Regulation Standards compliances


Plastic product design

Product Design & Development Steps

  • Establish Preliminary Design( Preliminary Concept Sketch and Sections)

  • Select the material( Expected End Use Requirement, Material Data Sheets)

  • a) Mechanical Properties used for essential component design calculations

  • b) Other Relevant Properties

  • 3Modify Design as per the calculations results and desired function

    • a) Specific property balance of selected grade

    • b) Processing Limitation

    • c) Assembly Method

    • d) Cost of Modification


Plastic product design

Product Design & Development Steps

  • CAD/CAE

    • Flow Analysis

    • Stress Analysis

  • 5Prototype and Testing

  • 6End Use Testing


Plastic product design

Polymer Fundamentals


Plastic product design

Polymer Fundamentals


Plastic product design

Polymer Fundamentals


Plastic product design

INTRODUCTION

  • Plastics were considered as “Replacing Materials”

  • Today’s world plastics are unreplacable materials on the same level as the classic materials:

  • Primarily due to special combination of properties (profiles & material combinations)

  • Plastics offers solutions, that are not possible with classic materials (Electronics, Medical care, Automotive industries etc.)

  • Low weight, allows high accelerations & decelerations.

  • Weather resistance (Corrosion) is better than resistance of metallic materials.

  • Good Electrical Isolation properties (Housings of Electrical devices)

  • Low manufacturing costs, especially with injection moulding technology.


Plastic product design

MATERIALS

Metals

(as Ores)

High-Molecular

(Makromolecular)

materails

Inorganic

e.g. Glasses

Organic

Natural

e.g. Wood

Synthetic resp.

Modified material

Thermoplastics

Thermosets

Elastomers

Crosslinkable

(vulcanisible)

elastomers

Crosslinked:rubber

Thermoplastic

elastomers

PLASTICS

CLASSIFICATION :


Plastic product design

Thermoplastics :

  • They are thread-like molecules (Linear & Branched)

  • They are always Deformable – Fusible – Soluble.

  • As degree of polymerisation (molecule length) increases strength & toughness increases, but flowability decreases.

  • They are further classified as

  • Amorphous thermoplastics &

  • Crystalline (Partially crystalline) thermoplastics


Plastic product design

Amorphous Thermoplastics:

  • Bulky thread-like molecules, with unarranged interconnected macromolecular structures, similar to that of staples in a cotton pad.

  • Transparent (Exception) : Styrol – copolymers with Butatein like ABS.

  • Lower degree of Shrinkage & high precision can be achieved with less cost.

  • High elastic properties between melt & freezing (Glass transition) temperature makes it to be produced at low holding pressure to avoid demoulding problems & high internal stress.

  • They are more sensitive against solvents & the parts are more suspectable to stress cracking.

Examples:

Polycarbonate (PC) , Polyvinylchloride (PVC), Acrylonitrile – Butadiene – Styrene – Copolymer (ABS), etc.


Plastic product design

Acrylonitrile – Butadiene – Styrene – Copolymer (ABS) :

  • Structure : amorphous Density : 1,03 – 1,07 g/cm³ Elastic-Modulus : ~ 2400 N/mm²

  • Properties :

  • High rigidity & toughness also at low temperature to – 40º C,

  • High Scratch resistance, High impact resistance, High suspectability to stress cracking

  • Temperature limits:

  • Short-Term ~ 100°C, Long Term ~ 85°C

  • Surface Quality :

  • High gloss surface can be achieved.

  • Natural colour: opaque, non-transperant

  • Manufacturing related properties :

  • Low shrinkage & low tendency to wrap,

  • Good Paintability & electroplatability.

  • Applications :

  • Automotive panels - (Interior & Exterior parts), etc.


Plastic product design

Acrylonitrile – Butadiene – Styrene – Copolymer (ABS) : Applications


Plastic product design

Polycarbonate (PC) :

  • Structure : amorphous Density : 1,20 – 1,24 g/cm³ Elastic-Modulus : ~ 2200 N/mm²

  • Properties :

  • High strength & Hardness, Toughness at low temperature.

  • High impact resistance, High suspectability to stress cracking

  • Temperature limits:

  • Short-Term ~ 135°C, Long Term ~ 100°C

  • Surface Quality :

  • High gloss surface can be achieved.

  • Natural colour: Transperant

  • Manufacturing related properties :

  • Low shrinkage & low tendency to wrap,

  • Good Paintability & electroplatability.

  • Applications :

  • Automotive panels - (Interior & Exterior parts), Headlights, Helmets, etc.


Plastic product design

Polycarbonate (PC) : Applications


Plastic product design

Polyvinylchloride (PVC) :

  • Structure : amorphous Density : 1,38 – 1,55 g/cm³ Elastic-Modulus : ~ 3000 N/mm²

  • Properties :

  • High hardness & stiffness.

  • High impact resistance at low temperature till -5°C, below this brittleness increases.

  • High suspectability to notch failure.

  • Temperature limits:

  • Short-Term ~ 70°C, Long Term ~ 60°C

  • Surface Quality :

  • High gloss surface can be achieved.

  • Natural colour: Transperant till Opaque

  • Manufacturing related properties :

  • Low shrinkage

  • High chemical resistance

  • Applications :

  • Ducts, Ventilation Channels, tubes, etc.


Plastic product design

Polyvinylchloride (PVC) : Applications


Plastic product design

Crystalline Thermoplastics:

  • Bulky thread-like slim molecules, which are alligned or with each other.

  • Non transparent (translucent), naturally coloured good slip properties.

  • Higher degree of Shrinkage due to higher package of molecules.

  • Are less compressible than amorphous during hardening & freezing temperatures, hardly faces any demoulding problems.

  • Due to higher shrinkage may form voids during cooling.

Examples:

Polyethylene (PE), Polypropylene (PP), Polyamide (PA), Polyacetal (POM) etc.


Plastic product design

Polyethylene (PE) :

  • Structure : Semi crystalline Density : 0.91 – 0.96 g/cm³ Elastic-Modulus : ~ 1200 N/mm²

  • Properties :

  • High stiffness & Hardness. Good elastic properties.

  • Practically unbreakable, ductile till -60°C

  • Temperature limits:

  • Short-Term ~ 135°C, Long Term ~ 80°C

  • Surface Quality :

  • High gloss surface can be achieved.

  • Natural colour: milky white

  • Manufacturing related properties :

  • No water absorption, High Shrinkage & tendency to warpage

  • High chemical resistance

  • Applications :

  • HR inserts, Ducts, Channels, etc.


Plastic product design

Polyethylene (PE) : Applications


Plastic product design

Polypropylene (PP) :

  • Structure : Semi crystalline Density : 0.90 – 0.92 g/cm³ Elastic-Modulus : ~ 1450 N/mm²

  • Properties :

  • High stiffness & Hardness. Stability higher than PE.

  • High flexural fatigue strength. Low impact strength at low temperature.

  • Temperature limits:

  • Short-Term ~ 140°C, Long Term ~ 100°C

  • Surface Quality :

  • High gloss surface can be achieved.

  • Natural colour: Colourless shining through

  • Manufacturing related properties :

  • No water absorption, High Shrinkage & tendency to warpage

  • High chemical resistance

  • Applications :

  • Car – Coverparts (Interior & Exteriors), etc.


Plastic product design

Polypropylene (PP) : Applications


Plastic product design

Polyamide (PA) :

  • Structure : Semi crystalline Density : 1.02 – 1.15 g/cm³ Elastic-Modulus : ~ 1300 - 2800 N/mm²

  • Properties :

  • High stiffness & impact strength.

  • Good friction & wear resistance

  • Temperature limits:

  • Short-Term ~ 170°C, Long Term ~ 110°C

  • Surface Quality :

  • High gloss surface can be achieved.

  • Natural colour: Translucent white-yellow

  • Manufacturing related properties :

  • Good flow properties & chemical resistance,

  • Not so good shrinkage. Tendency to warpage.

  • Applications :

  • Car – (Inner, Outer), Bearings, Gear wheels, etc.


Plastic product design

Polyamide (PA) : Applications


Plastic product design

Thermosets :

They are closely crosslinked, that is the reason they are non – thermoplastic.

They are always Non - deformable – Infusible – Insoluble.

Examples:

Epoxy (EP), Phenol-formaldehyde (PF), etc.


Plastic product design

Elastomeres:

They are loosely crosslinked, highly elastic & show very low plastic deformation.

They are highly deformable –Insoluble.

Examples:

Natural Rubber (NR), Ethylen-Propylen rubber (EOM, EPDM), etc.


Plastic product design

Design Guidelines

REQUIREMENT

(For what ?, strength, assy)

MATERIAL SELECTION

(Cost , Manuf Prosess,Temp conds, Strength, Safety)

PACKAGING DATA & KINEMATICS

( From customer)

DECIDING SNAP & SCREW FIXING LOCATIONS

(Locking 6 deg. Of freedom, DFA )

FIX TOOLING DIRECTION

(Die-Draw direction, Minimum silder’s and aesthetic requirement )

(Packaging data,

strength requirement)

DECIDING STRENGTHING RIBS,LOCATIONS & GEOMETRY

DRAFT ANGLES,RIBS WALL THICKNESS RATIO

(As per design guidelines)


Plastic product design

Design Guidelines

( Minimum core thickness, Slider ejection space, Sharp corners etc.)

TOOLING FEASIBILITY

DRAFT ANALYSIS A & B SURFACES

SECTIONS WITH PACKAGING THROUGH SNAP & RIBS

( Tolerance issues)


Plastic product design

Design Guidelines

Material Selection:

The wide variety of injection moldable thermoplastics often makes material selection a difficult task.

Factors governing material selection

  • Cost

  • Functionality

  • Assembly (Typically when bonded)

  • Temperature

  • Strength

  • Government Regulations.

  • Surface finish/aesthetic etc.


Plastic product design

Design Guidelines

Wall thickness/ Base thickness:

Proper wall thickness determines success or demise of a product. Like metals injection molded plastics also have normal working ranges of wall thickness. This can be taken into consideration while deciding wall thickness.

Factors to be considered while deciding wall thickness.

  • Structural strength of the part to be designed plays important role in deciding wall thickness.

  • Normal working ranges of wall from chart for particular material selected.

  • As a thumb rule 2.5mm.

  • Prior experience or bench mark parts can also be referred while deciding on wall thickness.


Plastic product design

Design Guidelines

Wall thickness/ Base thickness:

Once nominal wall thickness is decided, following are some design rules which should be followed.

  • Maintain uniform wall thickness wherever possible which helps in material flow in mold, reduces risk of sink marks, Induced stresses & consideration of different shrinkage

  • For non-uniform wall thickness change in thickness should not exceed 15% of nominal thickness & should transition gradually.

  • At corner areas minimum fillet at inner side should be 50% of wall thickness.


Plastic product design

Design Guidelines

Core-Cavity-Slider directions & Parting lines :

  • It is always recommended first to decide upon the core-cavity direction. Generally core-cavity direction & parting line depends upon following parameters

  • The shape & function of the component. Shape in turn is governed by A- Surface, packaging/environment data.

  • Core-cavity & slider directions should be considered such that they do not appear on A-Surfaces, unless otherwise specified & accepted by the customer.


Plastic product design

Design Guidelines

Draft Angles (On component walls):

Draft is necessary for ejection of part from the mold & are always Tooling (Die-Draw) & Slider direction.

Recommended draft angle is minimum 1deg.

Factors governing draft angle.

  • Surface finish – Highly polished mold requires less draft than an unpolished mold.

  • Surface Texture (Graining) – Draft increases with texture depth,normally 1 deg draft for every 0.025mm depth recommended.

  • Draw depth – To keep the draft angle to minimum as thumb rule draft angle – draw depth charts are followed & often design engineer should discuss with tool maker.


Plastic product design

Design Guidelines

Ribs :

Ribs should be used when needed for stiffness & strength or to assist in filling difficult areas.

For structural parts where sink marks are no concerns -Rib base thickness can be 75%-80% of adjoining wall thickness

For appearance parts where sink marks are objectionable: With texture (Graining) - Rib base thickness should not exceed 50% of adjoining wall thickness for part. Without texture (Graining) - Rib base thickness should not exceed 30% of adjoining wall thickness.

Some important points to consider while rib design.

  • Draft angle on ribs should be minimum 0.5 deg per side

  • Rib height should be 2.5 to 3 times of wall thickness for effective strength. Recommended to add multiple ribs instead of single large rib, Spacing between multiple ribs should be at least 2 times that of rib thickness.

  • Fillets at base of ribs should be 0.5mm Minimum.


Plastic product design

Design Guidelines

Bosses :

Usually designed to accept inserts, self tapping screws, drive pins etc for use in assembling or mounting parts.

Some important points to consider while Boss design:

  • The O.D of the boss should be ideally 2.5 times of screw diameter for self tapping screw applications.

  • If O.D exceeds 50% of adjoining wall thickness, thinner wall boss of O.D 2 times or less of screw diameter can be considered with supported by ribs.

  • Bosses should be attached to walls with ribs. Thickness at base of rib should not exceed 50% of adjoining wall thickness.

  • Boss inside & outside diameters should have 0.5 deg draft per side.


Plastic product design

Design Guidelines

Bosses :


Plastic product design

Design Guidelines

Coring :

Coring in injection molding terms to addition of steel to mold for the purpose of removing plastic material in that area Coring is necessary to create Pocket or, Opening in the part or to reduce heavily walled section.


Plastic product design

Design Guidelines

Openings :

Openings are desired in a part to eliminate sliders, cams, pullers, etc. to accommodate features like snaps. As general thumb rule 5deg angle in the area of mating of core & cavity is required.


Plastic product design

Design Guidelines

Assemblies :

Types of assemblies :

  • Molded-in assembly

  • Chemical bonding assembly

  • Thermal welding assembly

  • Assembly with fasteners.

Molded-in Assembly : (Snap fit, Press fit, molded in threads etc.)

This is generally the most economical method of assembly. Assembly is fast, inexpensive & does not require any additional part or substance. Minimizes changes of improper assembly. Some times tooling becomes complex & expensive.


Plastic product design

Design Guidelines

Snap fit assembly :


Plastic product design

Design Guidelines

Snap fit assembly :

Y = Deflection

Q values to be referred from Material graphs

Important points to remember :

  • Design for given assembly force or overlap length & material.

  • Deflection required to assemble the part should always be less than maximum deflection(strain) for safe design.

  • Snaps increase possibility of sliders wherever possible try to eliminate sliders by providing slot below snap or moving snap to outer edge of the part, if design permits.


Plastic product design

Design Guidelines

Press fit assembly :

  • Press fit design is more critical in plastics (Thermoplastics as they creep (Stress or Relax).

  • Good design should minimize stress on the plastic,by considering assembly tolerance between assembled parts & clamping force due to creep relaxation.


Plastic product design

Design Guidelines

Adhesive joints assembly :

  • Two similar or dissimilar plastics can be assembled in a strong leak-tight bond by using adhesives.

  • The choice of adhesive depends upon the application & the environment to which the part would be subjected.

  • Some of adhesives are Polyurethanes, Epoxies, Cyanoacrylates, Silicones etc.


Plastic product design

Design Guidelines

Bolts –Nuts - Screws :

  • Certain precaution must be taken while designing to reduce excessive compressive stress on the plastic.

  • Larger head screw or larger washer is preferred as that contact area increases & stress reduces.


Plastic product design

Design Guidelines

Molded in threads :

  • Coarse threads are preferred due to higher strength & torque limits.

  • Generally 0.8 – 0.9 mm relief should be provided to prevent high stress at the end of the threads.

  • To reduce the stress concentration minimum 0.25mm radius should be applied to the threads roots.

  • External threads should be as far as possible located on parting lines to avoid need of unscrewing mechanism.

  • Internal threads are usually formed by an unscrewing or collapse core.


Plastic product design

Design Guidelines

Self Tapping Screws :

Further classified in 2 types Thread cutting & Thread forming

  • Thread cutting screw is most used on brittle plastics such as thermosets & filled (50%) thermoplastics. They should not be reinstalled

  • Thread forming screws is mostly used on thermoplastics. They can be reinstalled for 3 to 5 times.

General Guidelines while using self-tapping fasteners:

Thread engagement length 2.5 times screw diameter

Boss diameter minimum 2 times of pilot hole diameter.

Cored hole should have 0.25 ° to 0.5° draft.

Holes should be counterbored or chamfered to a depth of 0.5mm to aid alignment & avoid cracking of boss.

Sufficient clearance to be kept between screw end & bottom of the hole.


Plastic product design

TOLERANCE RANGE TO BE GIVEN ON DWGS:


Plastic product design

HOW

SLIDERS & LIFTERS

WORK ?


Plastic product design

Molded Part

Undercut

Horn Pin

Slide

SLIDER FOR UNDERCUT :


Plastic product design

SLIDER FOR UNDERCUT :


Plastic product design

SLIDER FOR UNDERCUT :

Pulled Undercut


Plastic product design

SLIDER FOR UNDERCUT :

Cover tool

Molded part

Horn Pin

Locking Block

Undercut

Spring

Slide core


Plastic product design

SLIDER FOR UNDERCUT :


Plastic product design

SLIDER FOR UNDERCUT :


Plastic product design

SLIDER FOR UNDERCUT :


Plastic product design

LIFTER FOR UNDERCUT :

Lifter

Undercut

Angled pin


Plastic product design

LIFTER FOR UNDERCUT :


Plastic product design

LIFTER FOR UNDERCUT :


Plastic product design

LIFTER FOR UNDERCUT :

Molded part

Lifter

Undercut

Horn pin

Lose core


Plastic product design

LIFTER FOR UNDERCUT :


Plastic product design

LIFTER FOR UNDERCUT :


Plastic product design

LIFTER FOR UNDERCUT :


Plastic product design

HYDRAULIC CYLINDER FOR UNDERCUT :

Core pin

Undercut

Hydraulic Cylinder


Plastic product design

HYDRAULIC CYLINDER FOR UNDERCUT :


Plastic product design

HYDRAULIC CYLINDER FOR UNDERCUT :


Plastic product design

FORCED EJECTION :


Plastic product design

FORCED EJECTION :


Plastic product design

FORCED EJECTION :


Plastic product design

FORCED EJECTION :


Plastic product design

FORCED EJECTION :


Plastic product design

MULTIPLE UNDERCUTS

Molded Part

Slide

Hydraulic Cylinder


Plastic product design

MULTIPLE UNDERCUTS


Plastic product design

MULTIPLE UNDERCUTS


Plastic product design

MULTIPLE UNDERCUTS


Plastic product design

MULTIPLE SLIDERS:

Core Pin

Locking Block

Molded part

Horn Pin

Undercut

Spring

Slide


Plastic product design

MULTIPLE SLIDERS:


Plastic product design

MULTIPLE SLIDERS:


Plastic product design

REFERENCES:

  • Honeywell Injection Moulding Processing Guide (2002).

  • Honeywell Design Soultions (2002).

  • JCI Plastics Training Manual.

  • Injection Moulding Design by Pye


Plastic product design

THANK YOU


Plastic product design

Product Design & Development Steps

  • Design For Stiffness

    • Relation between load and deflection of the part is Stiffness

    • Determined by material and geometry of the part

    • Material Stress Strain Curves ( Young's Modulus)

  • Design For Strength

    • Max Load that can be applied to a part without resulting into part failure

    • Determined by Tensile stress strain curves( Tensile Strength etc)

  • Design for Behavior overtime

    • Creep : Time dependent Increasing Strain under constant stress

    • Stress Relaxation: Reduction of stress under constant strain


Plastic product design

Product Design & Development Steps

  • Design for Impact Performance

  • Ability of material to withstand impulsive loading

  • Factors: type of material, geometry, wall thickness, size of component,

  • operating temp, rate of loading etc

  • Design for appearance

    • Sink Marks, weld lines, air traps, voids, streaks, delamination, jetting, gate marks etc

  • Design for precision

  • Design for moldability

  • Design for Recyclability

  • Design for automation


Plastic product design

Part Application Requirement


Plastic product design

Material Selection Process


Plastic product design

Material Selection Process


Plastic product design

Design Based Material Selection


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Guidelines for Injection Molded Design


Plastic product design

Plastic Processing


Plastic product design

Plastic Processing


Plastic product design

Plastic Processing-Injection Molding


Plastic product design

Plastic Processing-Injection Molding


Plastic product design

Plastic Processing-IMD


Plastic product design

Plastic Processing-Injection Molding


Plastic product design

Assembly Techniques for Plastic parts


Plastic product design

Assembly Techniques –Snap Fits

Snap fit cantilever beam type

Snap fit cylindrical Type


Plastic product design

Assembly Techniques –Snap Fits

Factors for calculating cantilever beam for Snap fit


Plastic product design

Assembly Techniques –Snap Fits

Mold Design For Snap Fits


Plastic product design

Assembly Techniques –Spin Welding


Plastic product design

Assembly Techniques –Ultrasonic Welding


Plastic product design

Assembly Techniques –Hot Plate Welding


Plastic product design

Assembly Techniques –Adhesive Bonding


Plastic product design

Assembly Techniques –Ultrasonic Insertion


Plastic product design

Assembly Techniques –Screw and Bosses


Plastic product design

Assembly Techniques for Plastic parts


Plastic product design

Injection Mold


Plastic product design

Injection Mold


Plastic product design

Injection Mold- Slider and Stripper Plate


Plastic product design

Injection Mold- Stripper Plate


Plastic product design

Injection Mold- Stripper Plate


Plastic product design

Injection Mold-Hot Runner System


Tooling considerations for product design

Tooling considerations for product design.


Plastic product design

1. Maintain a uniform wall section - 2.0mm is typical. 2. Utilize the appropriate radii where applicable: 3. Strive to use snap fit and thread forming screws whenever possible to eliminate hardware, maximize design for assembly (DFA), and achieve the lowest cost.4. Draft is mandatory. 1.5 degrees per side, plus 1 degree per 0.001 depth of texture.5. Eliminate side draws (slides) and undercuts (lifters) whenever possible. Use through wall openings.6. Use the general tolerance box - tight tolerances drive up part and tooling cost.7. Do not put datum on flexible walls or points in space.

Plastic Design Major Messages


Plastic product design

Rib to Wall Ratio

Typical Rules for Rib Thickness

Conventional Thermoplastics - 0.7T some sink mark will come

- 0.4T for part which is visible. Structural Foam - 1.0T


Plastic product design

Uniform Wall Sections

It is important to use uniform walls to minimize warp age and maximize manufacturability potential.

Injection Molding : 2 to 4mmStructural Foam : 5 mmNo thin areas less than 1.5mmNo thick areas - core for uniform sections.

Always try to core from the ejector side of part.


Plastic product design

Draft Angles

Draft is needed to facilitate release of part from mold.

The draft to use, unless otherwise specified, is 1.5 degrees per side.

Indicate if draft is to be added or subtracted from nominal dimension.

Show draft on part whenever possible to avoid confusion as to direction.

The "No Draft Allowed" is not to be used. Even on critical areas allow 0.5 degrees.


Plastic product design

Limits of Undercuts

Eliminate undercuts by alternative redesign.

A minimum of 5 degree shut-off is required for all areas around a through opening. A 7 degree angle is even better.

See "Bad" steel conditions for steel limitations


Plastic product design

"Bad" Steel Conditions

Generally, "Bad" steel conditions can be avoided if all standing steel has a height to width ratio of 1:1 or better.


Slide core

Slide Core

Molded Part

Undercut

Horn Pin

Slide


Slide core1

Slide Core


Slide core2

Slide Core


Slide core3

Slide Core

Pulled Undercut


Slide core4

Slide Core

Pulled Undercut


Slide core5

Slide Core


Slide core6

Slide Core


Slide core7

Slide Core


Slide core8

Slide Core


Slide core9

Slide Core


Slide core10

Slide Core    


Slide core11

Slide Core

Excessive travel


Slide core12

Slide Core


Slide core13

Slide Core

Cover tool

Molded part

Horn Pin

Locking Block

Undercut

Spring

Slide core


Slide core14

Slide Core


Slide core15

Slide Core


Slide core16

Slide Core


Slide core17

Slide Core


Slide core18

Slide Core


Slide core19

Slide Core


Slide core20

Slide Core


Slide core21

Slide Core

Locking Block

Core pin

Molded part

Horn Pin

Undercut

Spring

Slide core


Slide core22

Slide Core


Slide core23

Slide Core


Slide core24

Slide Core


Slide core25

Slide Core


Slide core26

Slide Core


Slide core27

Slide Core


Slide core28

Slide Core


Slide core29

Slide Core


Slide core30

Slide Core


Accelerated lifter

Accelerated Lifter    

Lifter

Undercut

Angled pin


Accelerated lifter1

Accelerated Lifter


Accelerated lifter2

Accelerated Lifter


Accelerated lifter3

Accelerated Lifter


Accelerated lifter4

Accelerated Lifter


Accelerated lifter5

Accelerated Lifter


Accelerated lifter6

Accelerated Lifter


Accelerated lifter7

Accelerated Lifter

Crash condition


Hydraulic cylinder

Hydraulic cylinder

Core pin

Undercut

Hydraulic Cylinder


Hydraulic cylinder1

Hydraulic cylinder


Hydraulic pin

Hydraulic pin


Ejecting molded part

Ejecting molded part


Ejecting molded part1

Ejecting molded part


Actuating core pin

Actuating Core pin


Ejection of undercut part

Ejection of undercut part

Undercut

Hydraulic Cylinder

Slide Core


Ejection of undercut part1

Ejection of undercut part


Ejection of undercut part2

Ejection of undercut part


Ejection of undercut part3

Ejection of undercut part


Ejection of undercut part4

Ejection of undercut part


Ejection of undercut part5

Ejection of undercut part


Ejection of undercut part6

Ejection of undercut part


Ejection of undercut part7

Ejection of undercut part


Ejection of undercut part8

Ejection of undercut part  


Ejection of undercut part9

Ejection of undercut part


Pendulum core pin

Pendulum Core Pin


Pendulum core pin1

Pendulum Core Pin


Pendulum core pin2

Pendulum Core Pin


Pendulum core pin3

Pendulum Core Pin


Pendulum core pin4

Pendulum Core Pin


Pendulum core pin5

Pendulum Core Pin


Pendulum core pin6

Pendulum Core Pin


Pendulum core pin7

Pendulum Core Pin


Pendulum core pin8

Pendulum Core Pin


Pendulum core pin9

Pendulum Core Pin


Center rib with undercut

Center Rib with Undercut

Undercut


Center rib with undercut1

Center Rib with Undercut


Center rib with undercut2

Center Rib with Undercut


Center rib with undercut3

Center Rib with Undercut


Center rib with undercut4

Center Rib with Undercut


Center rib with undercut5

Center Rib with Undercut


Center rib with undercut6

Center Rib with Undercut


Forced ejection

Forced Ejection


Forced ejection1

Forced Ejection


Forced ejection2

Forced Ejection


Forced ejection3

Forced Ejection


Forced ejection4

Forced Ejection


Multiple undercut

Multiple Undercut

Molded Part

Slide

Hydraulic Cylinder


Die opening

Die Opening


Die opening1

Die Opening


Lifter ejection

Lifter Ejection


Part ejection

Part Ejection


Lifter return

Lifter Return


Slide return

Slide Return


Die closing

Die Closing


Multiple external slides

Multiple External Slides

Locking Block

Core Pin

Molded part

Horn Pin

Undercut

Spring

Slide


Multiple external slides1

Multiple External Slides


Multiple external slide s

Multiple External Slides


Multiple external slides2

Multiple External Slides


Multiple external slides3

Multiple External Slides


Multiple external slides4

Multiple External Slides


Multiple external slides5

Multiple External Slides


Multiple external slides6

Multiple External Slides


Multiple external slides7

Multiple External Slides


Multiple external slides8

Multiple External Slides


Multiple undercuts

Multiple Undercuts


Multiple external slides9

Multiple External Slides

Locking block

Core pin

Molded part

Horn Pin

Under

Spring

Slide


Multiple external slides10

Multiple External Slides


Multiple external slides11

Multiple External Slides


Multiple external slides12

Multiple External Slides


Multiple external slides13

Multiple External Slides


Multiple external slides14

Multiple External Slides


Multiple external slides15

Multiple External Slides


Multiple external slides16

Multiple External Slides


Multiple external slides17

Multiple External Slides


Multiple external slides18

Multiple External Slides


Angled lifter

Angled Lifter        

Molded part

Lifter

Undercut

Horn pin

Lose core


Angled lifter1

Angled Lifter


Ejection

Ejection


Ejection1

Ejection


Ejection2

Ejection


Ejection3

Ejection


Die closing1

Die closing


Die closing2

Die closing


Die closing3

Die closing       


Plastic product design

A

B

Impossible lifter condition

B

A


Thanks

Thanks


Plastic product design

Injection Mold-Hot Runner System


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