Design Example: Optimizing gates and ram
speed profile

Purpose of this example

This example illustrates various aspects of the power of CAE software for the plastics industry, and how such software can be strategically applied. It shows how to put into practice many of the concepts that are discussed in detail in the Design and Processing > Physics topics. These topics include injection pressure, filling pattern, melt-front area and melt-front velocity, runner design and balancing, and gate design.

Description of this example

The example steps through the design considerations for a molded plastic part in a concurrent engineering environment. It illustrates the role of computer simulation at each iterative step in the process. The software package used for this example is C-MOLD Process Solution. Phase I uses C-MOLD Filling EZ to analyze the initial design and determine the gate location and ram speed profile; Phase II uses C-MOLD Filling and Post-Filling for a more detailed nalysis of the material selection, part and tool design, and process conditions. china injection mold company

Phase I: Fast and easy simulation with C-MOLD Filling EZ

In this first phase of the design process, we run an initial simulation using C-MOLD Filling EZ, which performs a three-dimensional mold-filling simulation of Newtonian fluids under isothermal conditions. Filling EZ is designed for preliminary analysis of part, gate, and process designs. We then go through several design iterations, each time modifying the design variables (such as loaction and number of gates), rerunning the analysis, and observing the results. At the end of Phase I, we will have determined the best location for the gate and an optimal ran-speed profile.


An initial product design.


To determine the proper gate location and optimal ram-speed profile.

Design criteria

– Produce a uniform filling pattern with a minimum flow length and a minimum injection pressure requirement.

– Maintain a constant melt-front velocity to minimize property variation.

– Design for manufacturing and assembly, concurrent engineering, and early vendor involvement.