The Process
The process of completing a moldflow analysis in many ways depends on the objectives of analysis, which is why it is so important for the client to clearly communicate their objectives to the analyst. For this discussion, we'll stick to the most common use of flow analysis - gate location and warpage reduction.
The process usually goes something like this:
Phase 1 - Preliminary Gating
- Simulation modeling completed;
- Initial filling patterns are simulated based on some gating ideas established between analyst and client; some valve-gate sequencing may be done; a basic manifold layout may be included;
- Knit lines and flow balance are the key results;
- Preliminary hot drop and gate locations are sent to the manifold supplier and/or moldmaker;
- Some preliminary warpage studies may be completed (without cooling input) to help decide what is the best gating.
Phase 2 - Preliminary Cooling/Warpage
- Preliminary cooling lines and manifold layout from moldmaker are modeled an simulated;
- Key results are cooling time and temperature uniformity;
- Cooling adjusted to improve uniformity; higher conductivity inserts may be used;
- More in-depth warpage studies are done, which include the contribution from cooling.
Phase 3 - Final Design
- Final runner and gate sizing, cooling line placement, and process settings are provided in a final report to the client
Of course, there are many other steps involved in the process, most of which are handled by the analyst. Sometimes upward of 50 or 60 simulations are required to find that magic combination of part design, mold design, and processing that yield the best part!
