dupont - design check chart

8/7/2019 DuPont - Design Check Chart

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Design Check Chart

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D E L R I N H Y T R E L M I N L O N R Y N I T EZ Y T E L D EL RI N H Y T R E L M I N L O N

R Y N I T E Z Y T E L D E L R I N H Y T R E LM I N L O N R Y N I T E Z Y T E L D E L R I N H Y T R E L

M I N L O N R Y N I T E Z Y T E L D EL RI NH Y T R E L M I N L O N R Y N I T E Z Y T E L D E L R I NH Y T R E L M I N L O N R Y N I T E Z Y T E L

D E L R I N H Y T R E L M I N L O N R Y N I T EZYTEL DELRIN HYTREL MIN LON RYNITY T E L D EL RI N H Y T R EL M I N L O N R Y N I T

YTEL DELRIN HYTREL MINLON RYNITE ZY T E L D EL RI N H Y T R EL M I N L O N R Y N I T E ZHYTREL MINLON RYNITE ZYTEL DELRH Y T R E L M I N L O N R Y N I T E Z Y T E L D E L RH Y T R E L M I N L O N R Y N I T E Z Y T E L

DuPont Engineering Polymers

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Checklist

General

Performance Requirements (Structural,Aesthetic, etc.)

Combining Multiple Parts or Functions Structural Load (Static, Dynamic, Cycling,

Impact, etc.)

Environment (Temperature, Time, Chemical, etc.)

Tolerance Requirements

Life of Product

Quantity of Product vs. Fabrication Process

Secondary Operation

Packaging and Shipping

Environment

Temperature

Time Load

Other Environments (Chemical, Water,Humidity, etc.)

Engineering Design Facts

Type of Load

Frequency of Load

Stress Rate (Compression, Tensile, Flexural)

Strain Amplitude

Load Deformation (Tensile, Compression,Shear, etc.)

Apparent Modulus (Includes Strain Due to Creep) Direction of Load

Correlating Test Data With End Use

Safety Factor

Tests (ATIM, SAE, UL, Etc.)

Tension

Compression

Creep

Dynamic/Fatigue/Torsion

Impact

Poissons Ratio

Electrical Continuous Service Temp./U.L. Temp. Index

Material and Process

Directional Flow

Directional Layout of Reinforcements

Regrinding

Pre-drying

Prototyping (Machining, Molding)

Appearance

Style

Shape

Color

Surface Finish/Weld Lines/Flow Lines/Parting Line/Gate Location

Decoration

Economic Factors Cost of Present Part

Cost Estimate of Part in DuPont EngineeringPlastics

Faster Assembly and Elimination of FinishingOperation

Redesign Part to Simplify Product


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WRONG RIGHT WRONG RIGHT

Designing for Uniform Walls

Central gate

Problem may besolved by proper webdimension. In somecases properlydimensioned ribs maybe used to fill theexterior crown.

0.5T

Gate


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Designing for Ribbed Walls

Ribs

Adequate ribbing cancounteract bending.However, ribs shouldnot be used unlessnecessary (e.g., notfor small modulushigh precision gears.)

Stressed parts ina transparent

material show,under polarizedlight, the stressconcentrationeffect of sharpcorners.

Here are twoalternative solutions;their choice will dependon the torque to betransmitted.

Redesign has reduced high stressconcentration in snap-fit area.

Circular insertswith fine roundedknurling arepreferred. Theyshould not havesharp edges.Installing insertsafter molding mayalso be a solution.


Designing without Stress Concentration

Metal insert

5N

Wall


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Gate Location


Designing for Assembly

WRONG RIGHT WRONG RIGHTDesigning with Clearance on Threads

The two ways to solve this problem are:

A) Locate the gate in the thicker section(a long cycle may however be necessaryto pack the cavity properly).

B) Core out the part.

L should bekept larger (atleast D), anda flat headscrew would

eliminate tan-gential stressesA change ingate locationcould also help

~

Redesignedexterior snap-fitcap and additionof O ringeliminate leakage.

No undercut in themold. If the ratio

L:L1 increases,some ribs can beadded.

Engineering plastics usually resistcompression stresses better than

tensile stresses.Threads shouldbe provided around the exterior

diameter of theplastic part.An O ringensurestightness.

The O ring iscompressedradially. Additionaways to controlcreep could be:

1) Flanges may bestiffened by ribs, or

2) Metal rings all around,placed under the bolts.

Self-tappingscrew

Relief allowssnap-fit withoutbreaking

132

132

L1

L

PRESSURE

Gate


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Printed in U.S.A.[Replaces: H-30618-1]Reorder No.: H-81079 (99.3) DuPont Engineering Polymers

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For more information on

Engineering Polymers:

For Automotive Inquiries: (800) 533-1313

(800) 441-0575

StartwithDuPont

U.S.A.

East

DuPont Engineering PolymersChestnut Run Plaza 713P.O. Box 80713Wilmington, DE 19880-0713(302) 999-4592

AutomotiveDuPont Engineering PolymersAutomotive Products950 Stephenson HighwayTroy, MI 48007-7013(313) 583-8000

Asia PacificDuPont Asia Pacific Ltd.P.O. Box TST 98851Tsim Sha TsuiKowloon, Hong Kong852-3-734-5345

CanadaDuPont Canada, Inc.DuPont Engineering PolymersP.O. Box 2200Streetsville, MississaugaOntario, Canada L5M 2H3(905) 821-5953

EuropeDuPont de Nemours Intl S.A.2, chemin du PavillonP.O. Box 50CH-1218 Le Grand-SaconnexGeneva, SwitzerlandTel.: ##41 22 7175111Telefax: ##41 22 7175200

JapanDuPont Kabushiki KaishaArco Tower8-1, Shimomeguro 1-chomeMeguro-ku, Tokyo 153Japan(011) 81-3-5434-6100

MexicoDuPont S.A. de C.V.Homero 206Col. Chapultepec Morales11570 Mexico D.F.011-525-722-1456

South America

DuPont America do SulAl. Itapecuru, 506AlphavilleCEP: 06454-080BarueriSo Paulo, BrasilTel.: (055-11) 7266.8531/8647Fax: (055-11) 7266.8513Telex: (055-11) 71414 PONT BR

DuPont Argentina S.A.Avda.Mitre y Calle 5(1884) Berazategui-Bs.As.Tel.: (541) 319-4484/85/86Fax: (541) 319-4417

The data listed here fall within the normal range of properties, but they should not be used to establish specification limits nor used alone as the basis ofdesign. The DuPont Company assumes no obligations or liability for any advice furnished or for any results obtained with respect to this information.All such advice is given and accepted at the buyers risk. The disclosure of information herein is not a license to operate under, or a recommendation toinfringe, any patent of DuPont or others. DuPont warrants that the use or sale of any material that is described herein and is offered for sale by DuPontdoes not infringe any patent covering the material itself, but does not warrant against infringement by reason of the use thereof in combination with othermaterials or in the operation of any process.

CAUTION: Do not use in medical applications involving permanent implantation in the human body. For other medical applications, see DuPontMedical Caution Statement, H-50102.

http:/ / www.dupont.com/ enggpolymers/ americas

dupont - design check chart

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