The manufacturing of polymer products involves several processes, each with one-of-a-kind advantages and applications. Moulding is one of the main processes involved in the making of plastic, helping produce complex designs and shapes. Pressure and heat are used to fill the cavity of the mould (matrix) to create an end product. A powder liquid is placed into the hollow mould so that the polymer can take its shape. The chief difference between moulding and casting is moulding involves plastics while casting focuses on metals. By and large, it takes about eight weeks to get a mould ready for production.
Injection moulding is the most popular technique, so it shouldn’t come as a surprise there are many plastics available, ranging from highly durable polycarbonate to impact-resistant ABS. Injection moulding large plastic products requires larger machines that actually have a relatively small footprint made possible by their design. There are high upfront costs that make injection moulding viable only at high volumes, as it allows for high-tolerance precision, low scrap loss, and minimal post-production work. If you’re developing a product from scratch and are uncertain whether it will be successful in the market or not, injection moulding might not be the best solution.
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Injection Moulding Is the Most Cost-Effective Way to Make a Plastic Part at Scale
Injection moulding can be used in various circumstances, especially when producing heavy plastics or high volumes of small to medium parts incorporating bonded inserts. Indeed, the initial investment is high, but the cost per product is low. Other processing techniques require additional operations, such as polishing. Injection moulding is commonly used to make vehicle parts, including but not limited to fenders, grilles, bumpers, door panels, and light housings, to name a few. Smaller machines can produce precision parts for surgical applications, improving ergonomics and increasing functionality. The excess material can be recycled so that it can be reused.
Owing to the speed and efficiency of production, countless parts can be produced before the machine requires any maintenance. All parts produced are identical, which means that you can rely on high-quality products being made. The material and colour can be adjusted based on the customer’s requirement; there is very little post-production work required because the parts have a finished look upon ejection. One preparator can manage two or more injection moulding machines, so the labour is relatively low. The moulded parts can be unloaded automatically. As mentioned earlier, injection moulding has the advantage of using multiple plastic materials simultaneously.
Outsourcing injection moulding offers flexibility as regards business requirements. Quality, production, efficiency, and customer satisfaction all rely on making an informed choice from the available firms. Examine the expected production volume and the type of parts you wish to manufacture and select a reputable company with a strong track record demonstrating its ability to deliver high-quality products. It’s essential to assess the company’s manufacturing capabilities to determine if they have state-of-the-art machinery, technology, and resources. Equally important is to ensure the firm has robust quality control processes in place to minimise defects, ensure consistency, and guarantee satisfaction.
That Doesn’t Mean, However, That Injection Moulding Isn’t Without Its Drawbacks
Injection moulding isn’t suitable for the production of small quantities of plastic parts. The cost of machines and injection moulds is relatively high, which translates into the fact that the upfront investment is huge. What is more, injection moulding machine operators must have at least five to ten years of experience. Even if injection moulding is one of the most versatile of all plastic manufacturing processes, it’s not appropriate for all situations. A common and useful variation of injection moulding is structural foam moulding, which promotes weight savings of 20% owing to the foaming methodology. The actual savings can vary, yet leveraging structural foam moulding can result in parts that are 10%-30% lighter.
Structural Foam Moulding Is a Good Alternative to Injection Moulding
It’s an excellent idea to involve adequate engineering or manufacturing professionals to guide you in the early stages of the development process. Before you commit to structural foam moulding, it’s necessary to know all the facts first. Structural foam moulding, which involves combining a chemical blowing agent with a plastic resin, results in parts that are lightweight, strong, rigid, and impact-resistant. it has applications in various industries, such as medical, industrial, automotive, and more. For example, structural foam moulding can be used for the making of medical carts and cabinets, which need to be strong, lightweight, and easy to clean.
Although structural foam moulding is similar to injection moulding, it can be realised with less pressure than what’s typically required for standard processes, which is why the parts have thicker wall sections, giving the most flexibility. An inert gas is introduced into the melted polymer to reduce density and the weight of the finished product. The expanding gas holds pressure, filling the mould cavity. When the plastic comes in contact with the cold mould wall, producing a thin layer of skin. Structural foam moulding is associated with lower production costs, meaning it’s a worthwhile investment for lower-volume applications.
Several moulds can be processed at the same time (on the same machine), allowing for higher efficiency and flexibility in production. Aluminium moulds, for instance, can be used for large production runs and long-term durability. Even if aluminium tooling is used, it lasts as long as stainless steel owing to the lower pressure used. It goes without saying that not every part is suitable for structural foam moulding. Nevertheless, if you need a lower weight or more durable product made quickly and effectively, structural foam moulding is the go-to option. Optimised production ensures consistent part quality, minimising defects and rejects.
The Takeaway
All in all, the ability of injection moulding to produce countless parts in a short time period, so it’s ideal for mass production. Structural foaming can be used to manufacture parts that are lighter in weight but thicker and sturdier.; they’re structurally sound and have minimal warpage. It’s crucial to carefully consider your options and choose wisely.