Steel-Supported, Aluminum Injection Mold Frame Exhibits Durability, Strength

A mold frame that incorporates steel support pillars has all of the thermal benefits of aluminum matched with the durability of a steel mold—resulting in reduced cycle times combined with added strength and durability.

The AIM FRAME?—designed by Aluminum Injection Mold Company (Rochester, NY)—combines steel support pillars with an all-steel U-box with guided ejection to create a mold that avoids any possibility of overclamping the mold and crushing the part line.

 

Benefits of Aluminum

According to Aluminum Injection Mold Company President David Bank, the concept of the device is to add scaled steel support pillars that are in line with each other, between the alignment pins and bushings on two opposing sides of the “A” and “B” plates of an injection mold and have them contact a steel ejector housing/back plate. “The purpose is to allow the stack-up of steel to take all the repetitive clamp/closing pressure of any injection molding machine,” Bank notes.

“Aluminum is not considered an industry standard mold material due to its perceived softness or hardness as compared to a steel material,” Bank continues. “However, in the injecting molding process, an aluminum injection mold will offer a substantial reduction in cycle time when compared to its steel counterpart. Aluminum—with a thermal diffusity factor of 91—is nearly five times more efficient than a steel mold that has a thermal diffusity factor of 20. This means aluminum’s ability to manage either heat or cold is five times better. That is why the interest in aluminum molds is at an all-time high.”

Bank emphasizes the importance of debunking the myths of using aluminum in the injection mold process. “Most production injection molders will not buy and/or run an aluminum injection mold in their shop because they say their people will smash or crush the mold with the injection molding machine clamping pressure,” he states. “Having said that, an all-aluminum mold has had little play in the production arena. However, this addition to any production aluminum mold will offer the molder all of the thermal benefits of aluminum with the security of an all-steel mold. And, the concept can be scaled up or down in size—based on the size of the mold.

“With nearly 70 percent of all plastics molded today fitting into the ‘general purpose, unfilled resin’ category, the 10 to 30 percent cycle reduction using aluminum instead of steel could allow you to save a project, a good customer or your company,” Banks concludes.