Number of Mold Cavities for Die Casting
The number of mold cavities defaults to the value of the cost model variable defaultNumCavities or defaultNumCavitiesGravityDieCasting (1 in starting point VPEs).
You can override the default and specify the number of cavities, or request calculation of the number of cavities that minimizes total cost. You can also direct aPriori to calculate the number of cavities required to meet the annual production volume specified in the Production Scenario tab of the Cost Guide. See User Inputs for Die Casting.
If the user overrides the default, the actual number of cavities is the smallest number of cavities that (i) uses one of the layouts in the table below and (ii) equals or exceeds the number specified by the user or calculated by aPriori. The layouts minimize area for a given number of cavities, and are specified in the lookup table layoutNumCav.
 
Cavities Length Wise
Cavities Width Wise
Number Of Cavities
1
1
1
2
1
2
2
2
4
4
2
8
4
4
16
6
4
24
8
4
32
10
4
40
8
6
48
14
4
56
8
8
64
12
6
72
10
8
80
12
8
96

In order to calculate the number of cavities that minimizes total cost, the cost engine performs a full costing using each layout in the table above, and then chooses the one with the lowest cost.
Calculation of the number of cavities required to meet the specified production volume assumes round-the-clock production and depends on the following:
• Required annual volume
• Plant efficiency
• An estimate of cycle time