Geometrical Adjectives
Traditionally the basic characteristic of porosity in foam material production is defined as PPI — Pores Per Inch. The pore size has a certain dispersion, average values of pore size which are specified in the table below.
|
PPI |
Number of cells per centimeter |
Pore size |
The minimum technological thickness of unit |
||
|
Min |
Median |
Max |
|||
|
100 |
39,4 |
0,23 |
0,25 |
0,28 |
1,5 |
|
80 |
31,5 |
0,28 |
0,32 |
0,36 |
1,5 |
|
60 |
23,6 |
0,39 |
0,42 |
0,46 |
3 |
|
45 |
17,7 |
0,51 |
0,56 |
0,64 |
3 |
|
30 |
11,8 |
0,73 |
0,85 |
1,02 |
4,5 |
|
20 |
7,9 |
1,02 |
1,27 |
1,69 |
6 |
|
10 |
3,9 |
1,69 |
2,54 |
3,18 |
12 |
You may also find minimum technological thickness of the block in the table. This magnitude is defined by features of production technologies applied and is an estimated value. For some technologies and materials downward deviation is possible (for example for electrolytic nickel). But production of the block with these parameters is not rational, as the
