cavity deformation

[Rauno]

How to calculate cavity enlargement or deformation in injection mold? Is deformation
calulation used in real work? Part measurment is ...+-0,2 mm, material is PS. Wall thickness is 24,5;44;44;47 mm

 

[TheAnswerGuy]

Rauno,

In your description ?
I think what you are looking for is the typical shrink factor of Polystyrene????

If so, the number can vary due to part design, gating, wall thickness, additives and other variables. Usually these numbers are not printed do to these variables. But typically for standard unfilled, general purpose PS has a typical shrink factor of .005" inch per inch.

Hope this is what you were looking for.

 

[TheAnswerGuy]

Rauno,

You never answered back.
But I thought of your question when someone E-Mailed this information to me today. I don't know the author, but it may have some value to you.

-----------------------------------------
Shrinkage and warpage of molded parts is probably the most common of problems, yet has been ignored by publishers. Now, the first handbook dedicated fully to this problem is NOW AVAILABLE from Plastics Design Library.

HANDBOOK OF MOLDED PART SHRINKAGE AND WARPAGE ($245.00)

http://www.williamandrew.com/titles/723.html

This is the most comprehensive collection of shrinkage data ever compiled in a book and includes hard-to-find multi-point information on how materials, part design, mold design, processing, and post mold treatment affect the part’s shrinkage and warpage. The handbook explains in
plain terms why moldings shrink and warp, shows how additives and reinforcements change the picture, and sets out the effects of the molding process conditions. But, that’s not all. The handbook shows you how to alleviate problems by careful design of the molded part and the
mold, careful selection of materials, and proper process
techniques. And, most important of all, the handbook provides representative data to work with.

If you have specific questions about this title, please contact Brent Beckley by email at brent.beckley@williamandrew.com or by telephone at +1
607 648 4770 x673.
-----
William Andrew Inc. sends new book announcements on occasion to select individuals. Of course, if you do not want to receive announcements in the future, please REPLY to this email and type "REMOVE" in the subject line.