24 Jun Don’t Let LGF Molding Cost You a Fortune: Our Proven Optimization Strategies
During a joint customer call with Erik, we toured the facility of a large OEM that has their own injection molding division. As we were walking around the plant we were quickly escorted over to their 500-ton machine where they were running a 50% Long Glass Fiber (LGF) Polypropylene. The 3.5 lb. molded part was a structural component of their flagship line of products. It was described as a major headache in their production scrap report due to cosmetic defects that appeared to be clumps of long glass showing up randomly in the parts. While injection molded parts made from LGF compounds are not known to be aesthetically pleasing, these clumps were above and beyond the normal-looking LGF part. It was ugly, and understandably so, considered not acceptable from quality or marketing. The scrap rate was at times more than 35%. On top of that, the OEM was also wearing out their screw and barrel every year requiring an additional $20,000 to buy a new screw/barrel assembly!
In true Fixer fashion, we began challenging why they were using long glass fiber. The part design didn’t lend itself to maintaining the 11-12 mm long glass fibers. Normally, for LGF applications, parts are designed with thick walls greater than .200”. This part had nominal wall sections in the 0.150” and less, with tons of ribs that were only 0.080” thick.
We quickly made another interesting find. There were issues with the gate and runner system. Specifically, the gate and runner system weren’t designed to allow retention of the long fibers in this material. Additionally, this wasn’t the only part with this problem. There were other structural components that presented the same issues.
The next step for us: conduct an analysis on the parts and return to the customer with the results and our feedback. Upon returning with the test results, we were able to show them that because of the part design, along with the gate and runner system, they were only maintaining average glass fibers of 0.1 to 1.1 mm lengths. This result could be matched by using a standard glass fiber product that utilizes 2-3 mm short glass fibers. In addition to this, we felt that we could also challenge the glass content needed to meet their performance requirements. After a couple of samples and some testing performed by the customer, we were able to meet their needs using a 40% short glass fiber PP that virtually eliminated the clumps of glass scrap issue and reduced the overall wear on the screw and barrel. With the lower scrap and lower material costs, we were able to reduce overall costs by more than $330,000!
At this point in our relationship with the OEM, we weren’t even a supplier, but we had already added value to their business. Yes, we are a resin distribution company with 18 warehouses and a global footprint. However, we quickly showed the customer that we wanted to do more than just sell you plastic. We want to help fix your issues. We are the FIXERS! Let us show you a better buying experience.