Plastic injection molding is molding plastic parts into a specific shape. This process involves using a pressurized injection unit that forces molten plastic through cavities. The required injection pressure depends on the flow characteristics of the plastic, including viscosity and shear rate. The higher the injection pressure, the better, as it is essential to maintain the volumetric flow rate of the shot. Too little or too much pressure will result in defective parts.
Techniques used in plastic injection molding
The process of plastic injection molding requires a mold made of two halves. The front half is attached to the injection unit, while the rear half is attached to the movable plate. The front mold must be cleaned before the molding cycle begins. Once the mold is closed, the plastic material is allowed to cool.
Plastic injection molding uses different techniques to create parts. The process uses a single barrel with a plunger in older machines, while modern injection machines use separate barrels with varying injection mechanisms. The first barrel contains molten plastic, which passes through it and into the second barrel, which uses a plunger to transfer the plastic into the mold.
Designed molds must include complex geometries and features. Often, the mold must accommodate side action units and undercuts, as these will be inserted into the part cavity. The design of the mold may also require several iterations before it is ready for mass production.
When choosing a plastic injection molding company, it’s important to remember that price is not the only factor to consider. While a lower quote is always tempting, the cheapest deal may not be the best option in the long run.
In addition to the price, the company’s quality and experience should be considered.
Whether you’re looking for a low-volume molder or a high-volume one, it’s crucial to find a plastic molding company with the experience and expertise to meet your needs. The ability to manufacture your product within the specified time frame is essential. Furthermore, a high-quality plastic molding company should be able to guide you in material selection and mold design. The plastic molding company should also have a proven track record and good relationships with business partners.
Experienced engineers can advise you on the best materials for your project. This knowledge can eliminate the guesswork involved in choosing a material. In addition, they will be able to recommend lower material amounts. This knowledge can be beneficial over the life of an injection molded part.
Experience in plastic injection molding is an essential factor. A plastic molding company with years of experience can help keep costs low and your project within your budget. Many manufacturers invest in new machines or adapt old ones to increase production capacity. However, injection molding is a substantial investment; the most upfront costs are in the design and mold build. These costs are typically shared over the number of parts that are produced. As a result, the price per part will be lower when you choose a high-volume molding project.