A unique hardware/software resource that gives users of GE Plastics’ resins expert in-house technical support. It cap- tures the accumulated knowledge of experienced development engineers and molders to provide possible solutions to typical molding problems, and is presented in a text/graphics format that is easy to understand and use. Versatile and flexible, PETS has a variety of uses including:
Education and Training. Teach or test individuals or groups of new or less-experienced personnel on the latest diagnostic procedures. PETS can output to a variety of projection devices for group viewing.
Troubleshooting. Assist less experienced personnel in solving problems independently, quickly and cost-effectively.
Design. Address a number of considerations in the design and development of plastic parts - structural considerations, plastic behavior, molding considerations for parts and economic considerations.
Documentation. Generate printed records combining both text and graphics. These are valuable for use as educational reference or troubleshooting and to assist in mold evaluation, determining parts costs, and justifying mold improvements.
For pricing information and answers to specific questions about PETS, please call 1-800-845- 0600.
1-40 • Product Development PROCESS Extrusion Co-Extrusion Blow Molding Compression Molding Injection Molding Vacuum Forming Pressure Forming Structural Foam Gas Assist
Table 1-18. Plastic Conversion Processes vs. Key Considerations
CONSTRAINTS
• Limited Geometry. 2 Dimensional Shapes Only. • Constant Cross Section.
• Size: Large Parts Possible – Approx. 110 in. (2,795mm) max. Wide with Length to Suit.
• Materials: Most Thermoplastics.
Amorphous – Better than Crystalline for Shapes. • Aesthetic Surface Possible.
• Limited Geometry (Like Extrusion) 2 Dimensional Shapes. • Constant Cross Section.
• Large Parts
Width up to approx. 110 in. (2,795mm) max. Thickness <1.0 in. (25mm)
Cut to Length.
• Good Tolerance Control on Profiles. • Appearance… Good.
• Dissimilar Material Combinations. Protective Weatherable Surfaces Feasible. • Walls Typically Thin.
• Large Size Parts Possible. • Double Wall Geometry (Hollow). • Parts Limited to Hollow Shapes.
• Wall Thickness Vary as a Function of Draw Ratio. • Good Stiffness to Weight Ratio.
• Limited Tolerance Capability.
• Surface Finish Acceptable. But Not Class A. (Does Not Compare to Injection Molding.) • Some 3 Dimensional Detail Possible.
Standing Detail Difficult. • Large Part Capability. • Difficult to Maintain Flatness. • Non-Aesthetic Surface Appearance. • Can Accept Highly Reinforced Materials. • Low Tolerance Control.
• Part Size is Limited – Project Area <2000 in2 Typical. • Very Good Detail and Tolerance Control.
• Complex Parts. • Normally Thin Walls. • High Pressure Process.
• High Quality Surface Possible for Aesthetic Parts. • Low Tolerance Control.
• Large Part Capability. • Shape Limited by Draw Ratio. • No Standing Ribs or Other Detail. • Little Surface Replification of Mold.
• Better Tolerance Control Than Vacuum Forming: Still Loose. • Shape Limited by Draw Ratio.
• No Standing Features. • Large Part Capability.
• Enhanced Surface Replification. • Large Part Capability.
• Swirled Surface Appearance (Can be Improved With Counterpressure). • Heavier Wall Thickness (.250 in. [1.6mm] Typical).
• Wall Thickness Changes More Acceptable. • Part Size Similar to Injection Molding.
• Heavy Sections Can be Displaced by Air if Connected to Air Channel. • Very Good Tolerance Control.
• Injection Molded Surface Characteristics Typical. • Low Stress Molding.
COST FACTORS • Continuous Pro and Adds Ma • Moderate Tooli • Significant Star • Scrap – Purges/ • Continuous Pro • Moderate Tooli • Significant Star • Secondary Cutt • Scrap – Regrind • Tooling Modera • Suitable for Hig • Scrap – Trimme
• Tooling – Expen • Mold Charged b • May Require Tr • Suitable for Hig • Scrap – Reusab • Relatively Fast • Low Scrap – Ca • Expensive Mold • Moderately Slo • Trimming Scrap • Inexpensive Mo • Uses Sheet Sto • Secondary Ope • Moderately Slo • Sheet Stock Co • Trimming. • Moderate Tooli • Longer Cycle Ti • Slightly Lower • Finishing Costs • Similar to Injec • Process Patente • Cycle Time Com • Scrap – Reusab
Processing Considerations
COST FACTORS
• Continuous Process – High Production. Increased Thickness Slows Production Rates and Adds Material Cost.
• Moderate Tooling – Extrusion Die/Sizing/Cooling Die. • Significant Start-up Costs
• Scrap – Purges/Start-up Cutoffs, Can be Reground and Reused.
• Continuous Process – High Production. Increased Thickness Slows Production Rates • Moderate Tooling – Extrusion Die, Sizing and Cooling Die.
• Significant Start-up Costs. • Secondary Cutting and Trimming.
• Scrap – Regrind Results in New Product if Resin 1 and Resin 2 are Compatible.
• Tooling Moderate Costs. Cast Aluminum Molds Feasible. • Suitable for High Production.
• Scrap – Trimmed From Parts. Can be Reground and Reused.
• Tooling – Expensive, But Less Than Injection Molding Cycle. • Mold Charged by Heated Cut-to-Size Blanks: Labor Intensive. • May Require Trimming of Flash.
• Suitable for High Production. • Scrap – Reusable.
• Relatively Fast Cycle Times. • Low Scrap – Can be Reused. • Expensive Molds – Machined Steel.
• Moderately Slow Cycles Dependent on Thickness. • Trimming Scrap – Can be Reused.
• Inexpensive Molds – Wood or Cast Aluminum Acceptable. • Uses Sheet Stock.
• Secondary Operations: Trimming, Drilling, Finishing. • Moderately Slow Cycle Time.
• Sheet Stock Command Semi-Finished Goods Price. • Trimming.
• Moderate Tooling Cost: Cast Aluminum Feasible.
• Longer Cycle Time Than Injection Molding (+50%). • Slightly Lower Mold Costs Due to Low Pressure Process. • Finishing Costs For Appearance Parts.
• Similar to Injection Molding Tooling, Requires Gas Assist Equipment. • Process Patented. Royalties Need to be Checked.
• Cycle Time Comparable to Injection Molding. • Scrap – Reusable.
1-42 • Product Development
Previous Applications
Before undertaking a detailed material selection process, it is often worthwhile to deter- mine if a similar part has been made before, and if so, from which material it was made. If such an application exists, it may be advisable to conduct further investigation into the specifics of the par- ticular application to see whether newer or more appropriate materials could now be used.
Since it is impossible to list all applications – some grades are used for a multitude of parts in many industries – a relatively limited number has been listed.
This Application Matrix provides an overview of some typical applications in some of the numerous market seg- ments served by GE Plastics.
For further information on a particular grade, please con- tact your local GE Plastics’ representative.
Table 1-19. Application Matrix. Products CYCOLAC ABS Resin CYCOLOY PC/ABS Resin ENDURAN PBT Resin GELOY ASA Resin LEXAN PC Resin NORYL
Modified PPO Resin
NORYL GTX PPE/PA Resin SUPEC PPS Resin ULTEM PEI Resin VALOX PBT Resin XENOY PC/PBT Resin • ease of molding • surface quality • thermal stability • impact resistance • wide range of colors
• ease of molding • very good flow • low temperature impact • very good indoor UV stability • flame resistance
• chemical and stain resistance • dimensional stability • low water absorption • very good processibility • noise attenuation • excellent weatherability • heat resistance • impact resistance • aesthetics, colorability • transparency • high impact • dimensional stability • temperature resistance • flame resistance • electrical properties • dimensional stability • hydrolysis resistance • temperature resistance • low water absorption • flame resistance
• on-line paintability • low temperature impact • temperature resistance • chemical resistance • low mold shrinkage
• chemical resistance • inherent flame resistance • heat resistance • high strength
• very good electrical properties • chemical resistance
• temperature resistance • dimensional stability • inherent flame resistance • very good electrical properties • chemical resistance
• temperature resistance • flame resistance • fast molding
• high impact resistance • chemical resistance • dimensional stability • UV stability