Plastic manufacturing is one of the fastest growing manufacturing industries in the United States. From 1980 to 2015, employment in plastic manufacturing, which includes employment in plastic injection molding, outpaced the entire manufacturing sector by 1.5% each year on average. There are many reasons why manufacturers in the US love plastic, especially plastic injection molding.
Plastic injection molding is one of the fastest production processes in the world, lending itself well to mass production.
An injection molding cycle typically takes less than a minute and can sometimes only be a few seconds! Combine the quick cycle time with the fact that each cycle can produce multiple parts, and the output can be quite significant.
Unlike CNC machining, which cuts away plastic from a large block or sheet, plastic injection molding produces very little waste material.
For CNC machining, you might start out with a 100g block of plastic but by the end of the manufacturing process, you could be left with a final product that only weighs a few grams. Plastic injection molding is more efficient. Out of 100g of original plastic material, only 20g becomes waste on average.
Products made using the plastic injection molding process can be intricate, which can cut down on the number of separate parts needed to make a single object, further shaving down overall production time. By adding features such as unscrewing fixtures and core pulls, you can create parts with threads or side holes, eliminating secondary operations required when using other manufacturing processes. You can even mold your design or company’s brand right onto the part during the manufacturing process.
Low cost (in the long run)
Since plastic injection molding wastes less material than other types of plastic manufacturing like CNC machining, it is a less expensive processes. Plus, plastic is cheaper than other materials like metal and rubber.
Recycling is another cost-saving feature of plastic injection molding. You can recycle any leftover plastic that isn’t part of the final product by grinding it up. This by-product of the process is called “re-grind.” If you have enough regrind, it can be mixed with virgin material and used in process. It can also be sold to a factory that manufactures plastic parts with low cosmetic requirements, making the overall process even more affordable.
Once you pay for the initial cost of the mold, the labor costs are low to operate it. Over time, the mold’s high production rate will pay for some, if not all of itself.
Plastic injection molding is a highly repeatable process. With an injection molding machine, you can produce thousands of plastic parts in just one day, and they will all be of similar quality. Pending proper mold design, material selection, and product design, the rejection rate for plastic injection molding can be lower than one percent.
If consistency is important for your brand or project, plastic injection molding is an ideal manufacturing method.