Injection Mold Design & Build of a 16 Cavity Laboratory Tube (Micro-Centrifuge Tube)

Manufacturers that supply components to the medical device industry must maintain exceptionally high standard of excellence to ensure the overall quality and safety of the final product. In a very competitive market, these manufacturers are continually faced with the challenge of balancing quality, timeliness, and cost in order to grow their business and remain profitable.

Injection molding is a popular manufacturing method for plastic components used in medical devices. It allows for a high degree of design flexibility, and with the proper tooling and equipment, injection molding is capable of producing a large amount of parts per hour. Highly adaptable to automation, labor costs are low. With properly designed and built tooling, yield rates are very high and little if any post-production work is needed.

At Eagle Mold Co., Inc., we designed and constructed the injection mold highlighted here for the manufacture of components used in a micro-centrifuge. Based on the expected volume of parts, injection molding press size, and finished molded part size of .50" in diameter x 1.5" in length, our engineers determined that a 16-cavity design would match well with the production requirements.

When engineering the mold, our technicians had to lay out the cavities in a way that ensured a balanced flow of material into each of the cavities and a uniform cooling rate. This was essential for producing parts that were consistent and within specification. They also kept the flow length short to keep scrap to a minimum.

Built from stainless steel to within critical ±0.0002" tolerances, the mold featured an SPI A2 finish. We achieved this finish by grinding with finer and finer abrasives and then ending with a 3000 grit diamond buff. This highly polished surface ensured that the parts would have a good cosmetic finish with no evidence of parting line or tool marks. Throughout the entire tool build process, we conducted continual inspections using our shop floor CMM to ensure dimensional accuracy of the entire mold.

When put into production use, the high quality of the mold allowed much faster cycle times than the client had at first anticipated. Our mold design-build capabilities helped keep production costs low while satisfying a very demanding part quality profile.

Contact us today if you would like to learn more about our mold making capabilities.