July 9, 2020 Injection Molding Applications

Complete Plastic Systems can help to find a solution to get your machine back up and running quickly.

There are many different types of injection molding applications in today’s market. From automotive to medical you can expect that we have seen it all. One of the issues we were helping with was a broken drive end on a 45mm Toshiba injection molding screw which ended up breaking the drive end during a cold start situation. One thing great about most Toshiba screws is that they utilize a single keyway drive instead of an involute spline that takes more time to mill and in this case repair.

In this case the customer was molding parts for prosthetics in the Midwest of the United States. On startup, the Toshiba injection molding press was not completely up to the required temperature before his operators started the press. Since this was the case it caused the screw to break in the drive end of the screw.

The customer was able to pull the screw as well as the broken drive end without damaging the screw tip or the barrel and was able to overnight it for us to assess. During the inspection we were able to find that the Toshiba’s screw tip assembly was beginning to wear over the front of the retainer which would then completely render that package as unusable. Also, in our inspection we notice that the root of the screw was beginning to wear on the backside of the helix.

With many conversations between the end user and our team of engineers and manufacturing managers we quickly realized that the screw needed to be repaired and just not replaced. Unfortunately, we needed to get the customer running quickly so we repaired the screw to the best of our ability as well as supply a new tip assembly that was in stock.

While running the repaired screw we designed the screw with the correct steel specifications to include a tool steel with an extreme content of chromium to aid in cleaning and rid of any black specking. With an added nitride layer of .025” we ensured that the Rockwell of the Toshiba injection molding screw was at a high 72 which would ensure its longevity in that application.

Most screw suppliers in that situation may supply a customer with a chrome plated screw where the chrome would be laid .0015” per side. When you flash plate the chrome users have a tendency to see the chrome peel off premature under abrasive materials in turn causing black specking to occur or other types of degradation to the part.

The customer was extremely happy with the new screw and in running has been able to recover in less time as well as purge between colors faster. With this saved time his production numbers have increased to see a return on investment of his new screw within days.

Complete Plastic Systems is able to be flexible with both its customers budget and circumstance.  If you need to repair fast or replace your screw and barrels.  Complete Plastics Systems  can help to guide you to a solution that will get your machines back up and processing quickly.

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