Torsten’s Training Tips: Packing Pressure Profiles (Amorphous and Semi-Crystalline Materials)
One of the key steps in the injection molding process is the packing and holding phase, sometimes also referred to as the compensation phase. During the packing phase material is continuously “packed” into a cavity, thereby compensating for the shrinkage that occurs due to material cooling inside the mold. To optimize a packing profile, it […]
Torsten’s Training Tips: Ejector Pin Sub-Gates
The design and placement of gates are crucial elements in mold design, mainly because manufacturing parts often necessitate the absence of surface marks or gate remnants. To achieve this, certain gate styles are preferable over others. While many gate systems inevitably leave a witness mark, opting for a gate that integrates seamlessly with the ejector […]
Torsten’s Training Tips: Mechanical Material Behavior
Injection molding is a widespread manufacturing process used to create various everyday items, ranging from pipette tips to car bumpers, using different polymer materials. These parts can be made from either pure, unfilled polymers or those that are enhanced with reinforcements and additives. It’s crucial for designers of these parts to understand the mechanical behaviors […]
Torsten’s Training Tips: Mechanical Material Behavior
Injection molding manufacturing produces many everyday parts, from pipet tips to car bumpers in a variety of polymer materials. Some parts are produced from neat, unfilled materials and some from materials that are filled with reinforcements and additives. Part designers should be able to evaluate the mechanical material behavior and properties of these different polymers […]
Torsten’s Training Tips: Fill Speed Profiles
Evaluating and understanding fill speed profiles is an essential aspect of injection molding. Polymer materials can flow by heating them to their melting range. Every polymer has a melt and mold temperature range; within that range, the polymers flow and can be injected into a mold. The molten polymer is injected into the mold by […]
Torsten’s Training Tip: Polymer Materials Overview
It is important for part and mold designers not only to understand design principles, but also to understand the fundamentals of plastics. The choice of a plastic, or polymer, has a strong impact on the outcome of a molded part. Polymers are categorized by processing methods and temperature behavior. The major groups are thermoplastics, thermosets, […]
Torsten’s Training Tip: Gate Seal Time
Gate seal time is an important aspect of the packing phase that needs to be understood to produce high quality molded parts. Setting proper gate seal time plays a key role in packing parts. Properly packed parts will have even internal polymer molecular structure, fewer volumetric shrinkage differences, optimized part dimensions, and fewer sink marks […]
Torsten’s Training Tip: Thermal Pins
Designing thermally optimized molds becomes more challenging as part designs become more complex. There are various cooling design strategies, from using drilled coolant circuits or baffles and bubblers, to selecting mold steels or thermal pins (sometimes called heat pipes or heat tubes.) Thermal pins are a cooling strategy to optimize thermal behavior inside a mold. […]
Torsten’s Training Tip: Cashew Gates
Injection molded part quality is highly dependent on gate designs, sizes, and location. Because cashew gates, also called banana gates, can be placed in areas that are not visible, they are an option for molded parts that require perfect surface quality. Cashew gates, or banana gates, are sub-gates that are automatically de-gated and can be […]
Torsten’s Training Tip: Mold Steel Selection
Injection molds are designed and built to allow parts to be produced from various polymers and to be utilized for a variety of applications. A mold design team must possess the ability to evaluate and determine the optimal mold steel for each mold component to effectively produce high quality plastic parts. How do mold designers […]
