Equal Solidification Time



The solidification time is given by

t = B ( Volume / Surface Area )n

Since B and n are the same for both molding processes,
the equal solidification time condition is

Vcylinder / Acylinder = Vblock / Ablock

With cylinder diameter d and height h and
block cross section edge length a and block height b
this last equation becomes

{ ( Pi/4 ) d2 h } / { 2 ( Pi/4 ) d2 + Pi d h } = { a2 b } / { 2 a2 + 4 a b }

This gives the answer

b = { d h a } / { d a + 2 h a - 2 d h}

Two conclusions can be drawn from this result, and the display of it in the exercise,
- the general form of the dependence of solidification time on part size,
- the height of the prismatic part for equal solidification times, i.e., the answer to the question posed.


© 2002 by Barney E. Klamecki all rights reserved.