Top 5 Tips for Designing for Injection Moulding

When developing items, the injection moulding procedure is often given second-class consideration. Here are our top five suggestions for creating components that are completely compatible with the injection moulding process from the outset so you don’t needlessly postpone your next project.
  1. Plastic types for injection molding
Although the kind of plastic item you’re developing will influence the material you choose, there are additional factors that can need a trade-off between technical qualities, such as temperature or chemical resistance, moldability, and cost. Plastics that combine exceptional mechanical or chemical qualities with great moldability may often be used. There are over 80,000 distinct thermoplastic and thermoset materials, and there are 45 main classes of polymers, thus there are usually a lot of viable materials from which to pick for any application. We have a great deal of expertise dealing with a variety of polymers for injection moulding, from common plastics like polycarbonate and polypropylene to uncommon ones like PEEK (polyetheretherketone), PPSU (polyphenylsulfone), and biodegradable materials. These specialized materials for plastic injection molding are discussed in greater detail here.
  1. The location of the injection molding gate
Typically, the tool designer uses the most recent CAD and flow simulation tools to establish where the gates should be located in the injection mould tool. The position of the gate is essential for efficient injection molding. It has an impact on elements including component aesthetics and surface polish, warpage, tolerances, wall thickness, molded-in stresses, and the completed part’s physical characteristics. When designing components for injection molding, special attention should be paid to the position and type (fan, edge, or sprue) of gates. What could seem feasible at the component design stage can later turn out to be troublesome during the molding process. Again, early cooperation with our technical team will make it possible to optimize the design and placement of gates without affecting the part’s injection-moulding process or design.
  1. Important ranges
Injection molding delivers extraordinarily high levels of accuracy, as do other production techniques. However, a number of variables may have an impact on the dimensional tolerances of final injection-molded components. These consist of:
  • Materials selection: Different polymers shrink at various rates when they cool in the mold and after being ejected
  • the CNC machining of the injection mold tool and its design
  • The precision with which moving components and automation devices may be positioned, the injection molding machines’ build quality, and the process control systems’ capacity to maintain constant pressure and temperature levels
  • expertise and knowledge of machine operators.
When designing for injection molding, it’s crucial to keep these things in mind from the beginning. At this point, it will be more affordable to make changes to the part design, mold tool building, material selection, or injection molding technique to guarantee that the appropriate level of component tolerances are met. Ignoring these factors till the very last minute will surely lead to production delays and extra expenses.
  1. Sink stains and other injection molding flaws
A polymer always runs the danger of developing flaws whenever it melts, flows under pressure, and then cools. This is particularly true when it comes to plastic injection-molded items with intricate geometries. Typical flaws include:
  • Sink marks are often visible when underlying ribs or reinforcements are employed on the surface.
  • Flow lines are brought on by uneven cooling rates on a plastic surface.
  • Burn scars are often the result of the resin or air trapped in the mold tool heating up.
  • Warping – caused by too quick cooling
  • Overly high injection moulding pressure results in jetting.
  1. Working together early on in the design process with your plastic injection moulder
Of course, there are a lot more factors to take into account when designing components for injection molding, including shut-off angles, draft angle orientation, surface texturing, and the need for further finishing processes like assembly, testing, or printing, to mention a few. The overarching theme is to collaborate closely with our technical staff right away. This is crucial. By doing this, you can be confident that your injection molding project will be finished successfully, on schedule, under budget, and according to the specifications that your product designers have specified. You need to locate the very finest material that this injection moulding services has to offer so that you can choose it for the molding procedure. Resources:  

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