Cavitation Counts Chosen against a Volume Forecast Nobody Guarantees
Select initial tool cavitation against guaranteed first-year order volumes rather than unbacked sales forecasts to prevent balance sheet tooling write-downs.
Cavitation Strategy
Meaning
Production frameworks define the total number of mold cavities required to meet specific output goals within a defined project timeline. Selecting a cavitation strategy requires a balance between the upfront cost of the tool and the piece price of the finished part. A high cavity count reduces the labor and overhead costs per unit while increasing the complexity of the hot runner system and the risk of imbalance.
Throughput Calculation
Mathematical models determine the optimal cavity count by dividing the annual volume by the expected cycle time and machine availability. Adding more cavities increases the total parts produced per hour but often lengthens the cooling time because of increased thermal load on the mold. This calculation must account for the clamp tonnage of the press and the shot capacity of the barrel to avoid overloading the equipment.
A small increase in cavity count can sometimes push a job into a larger machine class.
Asset Investment
Capital requirements for multi-cavity tools scale with the complexity of the cooling channels and the precision of the parting lines. While a single-cavity tool is less expensive to build, the high per-part cost usually makes it unsuitable for high-volume production. Investing in a thirty-two cavity tool involves substantial risk if the part design is subject to frequent changes.
Mechanical Constraint
Designers often stop adding cavities when the flow length of the resin creates pressure drops that cause short shots. This boundary ensures that the mold remains stable and that cooling remains uniform across every part of the run. Mechanical limits of the mold plate size and the spacing of the tie bars determine the maximum possible cavitation for a given part geometry.