When contacting a plastics manufacturer about tooling procurement and, ultimately, contract manufacturing, there are many factors to consider. One of the most important factors to a successful production run is a good understanding of injection mold classifications. Understanding these guidelines can help you to avoid issues with your projects and ensure the quality and physical integrity of each individual item.
For each mold, there is a certain weight and production limit that is recommended. These guidelines were put in place by the Society of Plastics industry to ensure the uniformity of mold types, establish a mold quoting system and to ensure that each part or product that is molded has the same quality as the next. The Society of Plastics Industry has established five injection mold classifications, Class 101, Class 102, Class 103, Class 104 and Class 105. Here are some of the guidelines that distinguish between these five classifications.
Class 101 molds are by far the highest priced molds, but not only are they made with the highest quality materials, but they the highest yield of all of the classes. These molds are tooled for production runs of one million cycles or more. Cavities and cores must be hardened to a minimum of 48 R/C. Details such as heel blocks, wedge blocks, gibs and slides must be made of hardened tool steels. And, most importantly, the mold base must be a minimum hardness of 280 BHN. Injections must be guided and slides must have wear plates. Slides, cavities, and cores must have temperature controls wherever possible.
This class may see more expensive on the outset, but because it has the highest yield, the price per item is often far lower than molds in lower classes.
Class 102 molds are high to mid-priced molds, made with high quality materials that are built for medium to high yield production runs. However, to ensure the quality of the parts being produced, these production runs should not exceed one million cycles.
Class 102 molds are a great choice for use with abrasive materials and with part tolerance requirements. There are several differences between Class 101 and 102, but biggest difference is that slide wear plates, guided ejection, corrosive resistant, plated cavities, and temperature control channels may not be required depending on the anticipated part quantity.
Class 103 molds are medium to low priced molds that is recommended for production runs of fewer than 500,000. This mold is recommended for use with non-abrasive materials. With an recommended mold base hardness of 165 BHN and a cavity and core hardness of 280 BHN, all other extras are recommended, but not required.
Class 104 molds are the second to lowest priced molds, only higher than Class 105 molds. They are recommended for production runs of less than 100,000. Class 104 molds can be made from mild steel or aluminum and should not be used with abrasive materials. Hardness standards should be based on the size of the run and the materials used, but they are not required.
Class 105 molds the least expensive to tool, but also have the highest per item cost, because they are not recommended for production runs exceeding 500. Usually, Class 105 molds are only used to produce prototypes. Class 105 molds may be made from cast materials, such as epoxy or other strong composites. Essentially, this class requires the minimum strength to create a sufficient amount of parts, with the understanding that, most often, these parts will only be used as prototypes.
Count on Baytech Plastics, premier plastics manufacturer and tooling procurement specialists, to advise your company on which class of mold is right for your particular project, from a prototype run to a one million part productions run. Contact us for more information on tooling procurement and injection mold classifications.
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