Injection Molding Lab.

Design of Experiments Practice

ObjectivesGain some hands-on experience with

polymers, particularly injection moldingApply Design of Experiments (DOE)

methodology to an actual process

Experimental PlanExperiment set 1 – small team project

A simple 23 factorial design 3 variables – clamp force, injection

pressure, and injection time

Experiment set 2 – class project A 26 factorial design 6 variables – 3 + clamp time, melt

temperature, and mold temperature

Experimental Procedure

Injection molding process

Hello. I am a production manager.

This is a new injection molding machine!

What is the best process condition???

OK. Don’t worry.You can apply Design of Experiments to your process.DOE is an efficient experimentation methodology.DOE provides the maximum experimental information for the least expense.DOE allows you to optimize the process in terms of quality and/or quantity

Variables

Melt temperature Mold temperature Clamping force Clamping time Injection pressure Injection time

Check and Set up Melt temp. and Mold temp.

Adjust clamp force

Adjust injection pressure

Fill out hoppers

Press down the cover

Press to clamp

Press to inject & Measure holding time

Release to unclamp

Final product

Evaluate the product (Flash)

Group Best to Worst

#10 (Best – No Flash)

#1 (Worst – Huge Flash)

Evaluation Example

Fill-out capability

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