What happens if you think your part is molded perfectly and then find that it fails in the field?
Is it possible to determine if it is going to fail before the part is ever made? Fortunately, the answer is YES.
Optimizing the Process
In order to understand if a part is molded to the best of its ability, an analysis must be performed.
An analysis will provide such data as:
Part filling at the right speed?
Part packing effectively?
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Is the part being over-packed?
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When the part is being packed, is there too much shear stress?
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Is the part under-packed and causing voids or sink marks?
Maintaining Part dimensional stability
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Is the gate in the best location?
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Is the shear stress causing deflection?
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Is the cooling causing warpage?
Virtual Field Testing
Once an analysis has determined the optimum processing conditions for the part, the part will most likely contain inherent stress from the molding process. It is this stress that may be the ultimate cause of failure in the field.
Frozen-in stress coupled with functional stress imparted during usage may cause the part to fail and this must be headed off before the parts ever make it to the field.
This is when it's vital to run a post process using FEA.
Stress Analysis using FEA
Moldflow has the ability to export the frozen-in stress data to an external FEA package such as Ansys or Abaqus.
These FEA packages can read the mesh (along with the stress data) into their environment and calculate any forces which may be applied to the part.
Because the frozen-in stress is accounted for, it may be found that the part would fail when it normally wouldn't have failed if the frozen-in stress was not accounted for. Frozen-in stress is crucial data to have in order to create a successful part.
If you have the need to ensure your part will perform in the field and exceed expectation then it is vital to run a:
Process Optimization utilizing the Moldflow software
AND
Post Process Stress Analysis using Ansys or Abaqus (or similar software of the same capabilities)
Bozilla Corporation has performed this unique set of analyses and identified many potential causes of failure long before the parts were ever manufactured.
Contact Bozilla Corporation for your FEA and injection molding troubleshooting needs and please visit our website at www.BozillaCorporation.com.
