The weekend comes to an end and the time comes to bring the molding floor back online for the beginning of a new work week. A molder can sometimes dread the tasks associated with a full plant restart. There are many potential failures that can occur as a plant is returned to a production state. Despite these risks, much of the headache can be avoided simply through proper shutdown and start up procedures. The following article addresses many key components that often lead to poor restarts. It also provides insight into some of the methods that can be implemented to not only reduce system breakdowns, but also can offer smoother start-ups with fewer problems…
Plastic injection processing has experienced massive change in the last 20 years. The days of molding by time and pressure have given way to molding by position, peak pressure and robust process. RJG and John Bozzelli were major pioneers in the development of decoupled and scientific molding as the procedures were developed and given structure. Plastic injection as an “art” gave way to plastics processing as a science of repeatable, standardized processes.
It is possible for machines to run too fast—find the sweet spot where maximum output overlaps with good parts.
In today’s fast paced plastic injection industry, lean manufacturing is a primary driver of profitability. Without lean, organizations find their operations are sluggish and ineffective. This not only affects a company’s ability to successfully grow and prosper, but the capability of taking on new work also suffers because current systems have not been effectively streamlined. This article addresses cycle time optimization, outlining the different variables within the molding process that can be used to maximize profits.
One of the first points that needs to be made when addressing this topic is to acknowledge that it is possible for machines to run too fast. Every molding job is different, and the following conditions must be satisfied to properly assure that the optimization is successful……
You can only imagine how exciting it was for industrial engineers and researchers when they were conducting research to understand the strategy and tools behind Toyota’s meteoric growth.
All the studies showed that Toyota was faster, with less costs and inventory, and delivering a higher quality compared to the American and European automakers. And it wasn’t by a small amount; Toyota used a small fraction of the inventory yet built cars on time every day with high quality…..
A lesson on shear induced melt variations ends some confusion regarding balancing runner systems
for multi-cavity molds.
The Beaumont Effect is recognized as the source of mold filling imbalances and product variations in molds
with four or more cavities. The worst failures caused by the phenomena can be most easily (visually) recognized
in molds with 8 or more cavities. However, shear induced melt variations impact every injection molded
part, with a greater influence than most realize….
It is curious that in a world that relies increasingly on documentation, the attention to the details of polymer composition receive so little attention. Companies will fill volumes with procedures for various aspects of their manufacturing processes. However, no serious consideration is given to verifying the composition of the raw materials that are used to produce the various molded parts until there is a problem. Instead, there is a tendency simply to refer back to whatever published information is available from the material supplier….
Viscosity is a very large category that has huge effects on standardizing molding processes. It is also one of the most important factors in a molder’s arsenal of making process changes. This article will first explain viscosity, and then delve into different situations where viscosity may help or be hurting a processors goal of zero scrap and high output…..
When trying to establish process control in plastic injection, watering the tool is a key variable that is often overlooked. Water set-up and design are every bit as important as establishing and recording a repeatable process. The steps taken when watering a mold are key to a processor’s goal of consistency. If during the design and development stage, watering is put on the back burner as an “unimportant” variable, the potential for lost process control is huge.
Below are some insights into the most important facets of cooling or heating your mold, as well as what recordable data are important in the initial stages of process engineering…