American Plastics Industry Conference in-depth discussion of mold technology

DougEspinoza, TZero project manager at RJG, said the consulting firm helps engineering and production units design "first-time perfect" tools, and the key is to get ready before the production begins.He suggested that the mold manufacturer record and verify the process of the molded parts."Grasping the molding process is half the success." 

Espinosa says TZero records orderly planning to help communicate when designing injection molding molds.

Training and education are key, and what many companies are missing is communication between departments, and the flow charts must be detailed to track progress and encourage collaboration."To do this, we have to work together and solve problems."

TZero helped design experiments to test a series of assumptions, and Espinoza said, " We will work in the factory workshop for two weeks to help solve the problem."

TZero uses analog production, RJG is licensed by Sigmasoft, Moldex3D and AutodeskMoldflowInsight, and Espinoza reviews parts design and mold design, saying that " cooling is an important factor."

Measuring mechanical performance is also very important, with TZero experts preferring to obtain real data on production, not only simulated data.Espinoza said: " cannot only use machine specifications and input, must obtain actual on-machine data."

Changes in resin viscosity affect the part quality, so he suggested monitoring the history of cavity pressure in the mold, using the DecoupledII and DecoupledIII processes provided by RJG.

hot runner

The Innovation and Emerging Technologies Conference attracted 185 attendees and 30 gave live presentations, two of whom discussed heat flow control.

MarcelFenner, technical manager and president of Priamus Systems Technology, said balancing multi-hole molds is necessary to prevent uneven filling.The causes of the change include the different positions of the thermal coupling and some other factors."The biggest factor is the change in resin viscosity."

Priamus worked with Synventive (a sister company of the Barnes Group) to develop technology to electronically handle heat channel temperature.Fenner says it precisely controls the part length and part weight of the multi-cavity mold, and even the series mold is internally unbalanced.

EricGerber, an engineer at Sigma Plastic Services Ltd, of Swalburg, Illinois, argued that shear rate differences in thermal channel systems cause the flow imbalance associated with viscosity changes.Other factors affecting the flow rate include flow distance, die cavity pressure and temperature in the mold or in the heat flow channel manifold.

PaulMaguire, president and CEO of Riverdale Global, Pennsylvania, said 100% penetration, outlined Riverdale's RGInfinity system that automatically refills color containers at low levels.

Maguire also described another system, where plastic processors can fill the barrels and their own color scheme, which he called the "Home Depot method".

Injection / compression molding

TrevorPruden, technical and engineering manager at Rockhill Abbott, CT, talked about injection molding / compression molding, or "compression molding" with low physical stress and internal stress balance throughout the part.This processing method prevents the generation of deposition traces, reduces part warping, and can be used in multiple materials, such as thermoplastic, powder spray, and liquid silicone.

For certain parts, the pressure die is a good method such as LED optical lens and semizystal polymers.

DanSpohr of Bartenfield, of Turrington, Conn, believes it is a good idea to replace older ones with new robots, which can move based on injection and die functions.For example, an older robot needs to separately determine whether the part is located at the arm tool end, then remove the part from the mold tool, and finally allow the machine to shut down, which takes 3 seconds to complete these tasks, while the new robot takes less than 1 second."So molding companies can make money, I hope the mold will open as short as possible."