Blow molding is a manufacturing process in which hollow plastics are formed. A hollow thermoplastic preform is heated and blown inside of a closed mold. The result is the plastic is able to conform to the shape of the cavity within the mold. This very useful process is used to create a huge number of hollowed out parts, including plastic bottles. The steps of completing blow molding are quite intricate and require the expertise of someone who is highly experienced in the process to complete it.
The process of blow molding begins with a mockup of the part that you want to make. The product can begin with either a sketch or an idea. From there, a three dimensional drawing through a CAD program is designed. The three dimensional design makes it easier to visualize the part you are making before it is time to create the physical mold or model. This allows you to measure and rotate the virtual design in order to get a good feel for the dimensions at the start. You can also take care of any structural or functionality issues right from the start, which will save you time, money and materials in the long run. Using three dimensional modeling, you can also communicate with the supplier to make sure they are able to meet your needs.
Once the product has been designed, you can start thinking about the mold that needs to be designed and built. Having a stable and flawless blow mold is the most important part of creating the blow molded part. There are many different blow methods, including stretch blow molding, injection blow molding, extrusion blow molding and more. Each method has its own unique requirements and capabilities that must be well thought out. The next steps in the process to be considered are the materials and the cooling needs. Water lines are usually found in these molds to aid in the cooling and hardening of the plastic.
After the final formed product has cooled, it needs to be ejected from the mold. This means you have to consider the mechanics of the mold to be sure the plastic can be ejected easily. If there are foldable or collapsible parts, it is necessary to install some hydraulics of some sort to make it easier for you to eject, for instance. Because the hot plastic will shrink when it cools, you will need to consider the shrinkage that is going to occur and build a mold that will create something large enough to shrink down to the proper size in the end.
Once all of that is completed and the mold is built, quality checks will need to be run before it goes into production. All of this is quite an intricate process that takes some serious know-how. For this reason, you should hire a freelance blow molding expert to do the job. Our blow molding services at Cad Crowd make it simple to get the job done. Contact us for a price estimation today.