Number of Mold Cavities
The default number of cavities is the maximum number of cavities that can fit on the selected machine, using a layout from the table below (see Machine Feasibility and Selection for Sand Casting )--with the following exceptions:
• Manual Floor Moldmaking routings with large parts (that is, parts whose weight is at or above the value of the cost model variable largePartThreshold--1000kg in the starting point VPEs)
• Manual Pit Molding routings
For these routings, the number of cavities always defaults to 1.
For all routings, you can override the default and specify the number of cavities, or request calculation of the number of cavities that minimizes total cost. See User Inputs.
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